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Sample records for range system viability

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  2. Evaluation of bacterial recovery and viability from three different swab transport systems.

    PubMed

    Tan, Thean Yen; Ng, Lily Siew Yong; Sim, Diana Miao Fang; Cheng, Yvonne; Min, Melissa Ong Hui

    2014-04-01

    This study evaluated three types of swab transport systems for organism recovery. Swabs with transport media were further assessed for organism viability over 24  hours over a range of different storage temperatures. Test organisms consisted of aerobes, fastidious aerobes and anaerobes. Swabs were tested according to the standardised quantitative elution method published by the Clinical Laboratory Standards Institute (CLSI; M-40A). There were substantial differences in primary organism recovery, with recovery rates from different swabs ranging from <0.1% to 78% for Streptococcus pyogenes. Similar differences were noted for other test organisms. In general, the flocked swab (ESwab) demonstrated highest rates of recovery for aerobic organisms, while higher rates of recovery of Fusobacterium nucleatum were demonstrated from a standard swab (Transwab). When considering organism viability, no single swab fulfilled all the criteria stipulated by the M-40A standard for all organism/temperature combinations. Organism viability was marginally better for the gel-based swab transport systems as compared to the liquid-media based ESwab. Significant differences between swab transport systems were demonstrated, including differences for primary organism recovery and viability. The ESwab showed the best recovery of organisms, while gel-based media demonstrated marginally better bacterial viability for most tested retention times and temperatures.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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…

  8. Male-specific genotype by environment interactions influence viability selection acting on a sexually selected inversion system in the seaweed fly, Coelopa frigida.

    PubMed

    Edward, Dominic A; Gilburn, André S

    2013-01-01

    In the seaweed fly, Coelopa frigida, a large chromosomal inversion system is affected by sexual selection and viability selection. However, our understanding of the interaction between these two selective forces is currently limited as research has focused upon a limited range of environments. We allowed C. frigida larvae to develop in two different algae, Fucus and Laminaria, and then measured viability and body size for each inversion genotype. Significant male-specific genotype-by-environment interactions influenced viability and body size. For males developing in Laminaria, the direction of viability selection acts similarly on the inversion system as the direction of sexual selection. In contrast, for males developing in Fucus, viability selection opposes sexual selection. These results demonstrate that through considering viability selection in different environments, the costs and benefits associated with sexual selection can be found to vary.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. The economic viability of pursuing a space power system concept

    NASA Technical Reports Server (NTRS)

    Hazelrigg, G. A., Jr.

    1977-01-01

    The development of a space power system requires no fundamental technological breakthroughs. There are, however, uncertainties regarding the degree to which necessary developments can be achieved or exceeded. An analysis is conducted concerning the implementation of a 5000 MW space-based solar power system based on photovoltaic conversion of solar energy to electrical energy. The solar array is about 13 km long and 5 km wide. Placed in geosynchronous orbit, it provides power to the earth for 30 years. Attention is given to the economic feasibility of a space power system, a risk analysis for space power systems, and the use of the presented methodology for comparing alternative technology development programs.

  14. The Viability of Using Various System Theories to Describe Organisational Change

    ERIC Educational Resources Information Center

    Sullivan, Terence J.

    2004-01-01

    This article discusses the viability of concepts such as complex systems theory, evolutionary theory and chaos theory as metaphors for being able to give a global perspective of one particular school described in a previous article entitled "Leading people in a chaotic world." The article restates and re-explains this one particular case in…

  15. Short range miniaturized biotelemetry system

    NASA Technical Reports Server (NTRS)

    Lorenz, R.

    1975-01-01

    A biotelemetry system for measuring and transmitting EKG, EMG, and EEG data by an RF link to a receiver was designed, developed, and delivered. The system is battery operated with the batteries and transmitting electronics an integral part of the electrode sensors. The low frequency response of 0.05 Hz assures faithful reproduction of detailed EKG and all measurements are made by the utilization of two electrode sensors.

  16. 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.

  17. 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.

  18. A thermal vacuum-UV solar simulator test system for assessing microbiological viability

    NASA Technical Reports Server (NTRS)

    Ross, D. S.; Wardle, M. D.; Taylor, D. M.

    1975-01-01

    Microorganisms were exposed to a simulated space environment in order to assess the photobiological effect of broad spectrum, nonionizing solar electromagnetic radiation in terms of viability. A thermal vacuum chamber capable of maintaining a vacuum of 0.000133n/sq m and an ultraviolet rich solar simulator were the main ingredients of the test system. Results to date indicate the system to be capable of providing reliable microbiological data.

  19. The influence of pleiotropy between viability and pollen fates on mating system evolution.

    PubMed

    Jordan, Crispin Y

    2015-02-01

    Floral displays are functionally and genetically integrated structures, so modifications to display will likely affect multiple fitness components (pleiotropy), including pollen export and self-pollination, and therefore selfing rate. Consequently, the great diversities of floral displays and of mating systems found among angiosperms have likely co-evolved. I extend previous models of mating system evolution to determine how pleiotropy that links viability (e.g., probability of survival to reproduction) and the allocation of pollen for export and selfing affects the evolution of selfing, outcrossing, and in particular, mixed mating. I show that the outcome depends on how pollen shifts from being exported, unused, or used for selfing. Furthermore, pleiotropy that affects viability can explain observations not addressed by previous theory, including the evolution of mixed mating despite high inbreeding depression in the absence of pollen-limitation. Therefore, pleiotropy may play a key role in explaining selfing rates for such species that exhibit otherwise enigmatic mating systems.

  20. 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.

  1. 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.

  2. The Geoscience Laser Altimetry/Ranging System

    NASA Technical Reports Server (NTRS)

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

    1987-01-01

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

  3. Neuro-fuzzy systems for computer-aided myocardial viability assessment.

    PubMed

    Behloul, F; Lelieveldt, B P; Boudraa, A; Janier, M F; Revel, D; Reiber, J H

    2001-12-01

    This paper describes a multimodality framework for computer-aided myocardial viability assessment based on neuro-fuzzy techniques. The proposed approach distinguishes two main levels: the modality-independent inference level and the modality-dependent application level. This two-level distinction releases the hard constraint of multimodality image registration. An abstract description template is used to describe the different myocardial functions (contractile function, perfusion, metabolism). Parameters extracted from different image modalities are combined to derive a diagnostic image. The neuro-fuzzy techniques make our system transparent, adaptive and easily extendable. Its effectiveness and robustness are demonstrated in a positron emission tomography/magnetic resonance imaging data fusion application.

  4. 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. PMID:27063422

  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. Expert systems and ballistic range data analysis

    NASA Astrophysics Data System (ADS)

    Hathaway, Wayne; Steinhoff, Mark; Whyte, Robert; Brown, David; Choate, Jeff; Adelgren, Russ

    1992-07-01

    A program aimed at the development of an expert system for the reduction of ballistic range data is described. The program applies expert system and artificial intelligence techniques to develop a mathematically complex state-of-the-art spark range data reduction procedure that includes linear theory and six-degree-of-freedom analysis. The scope of the knowledge base includes both spin and statically stable vehicles. The expert system is expected to improve the quality of the data reduction process while reducing the work load on the senior range engineer.

  8. 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.

  9. 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.

  10. Viability and distribution of bacteria after passage through a circle anaesthetic system.

    PubMed

    Murphy, P M; Fitzgeorge, R B; Barrett, R F

    1991-03-01

    We have assessed in vitro the viability of eight species of micro-organism suspended as aerosols and passed through a soda-lime absorber rebreathing system. As had been predicted, the soda-lime exerted a potent cidal effect on non-sporing organisms, all of which were rendered non-viable. One percent of the spore bearing organism, Bacillus subtilis, was still viable after 30 min contact. Although Bacillus subtilis is an organism of low pathogenicity, spores may be more resistant to the alkaline medium of the soda-lime. The micro-organisms were observed to lodge in all components of the breathing system, with the greatest concentration being recovered from the corrugated tubing. We recommend that disposable components of the circle breathing system should be changed, and the non-disposable parts sterilized or disinfected, daily. Soda-lime cannisters should be sterilized or disinfected when changing the soda-lime. PMID:1901723

  11. Autonomous system for launch vehicle range safety

    NASA Astrophysics Data System (ADS)

    Ferrell, Bob; Haley, Sam

    2001-02-01

    The Autonomous Flight Safety System (AFSS) is a launch vehicle subsystem whose ultimate goal is an autonomous capability to assure range safety (people and valuable resources), flight personnel safety, flight assets safety (recovery of valuable vehicles and cargo), and global coverage with a dramatic simplification of range infrastructure. The AFSS is capable of determining current vehicle position and predicting the impact point with respect to flight restriction zones. Additionally, it is able to discern whether or not the launch vehicle is an immediate threat to public safety, and initiate the appropriate range safety response. These features provide for a dramatic cost reduction in range operations and improved reliability of mission success. .

  12. 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.

  13. 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.

  14. Transponder System for High-Frequency Ranging

    NASA Technical Reports Server (NTRS)

    Lichtenberg, C. L.; Shores, P. W.; Kobayashi, H. S.

    1986-01-01

    Transponder system uses phase difference between transmitted and reflected high-frequency radio waves to measure distance to target. To suppress spurious measurements of reflections from objects near target at transmitted frequency and its harmonics, transponder at target generates return signal at half transmitted frequency. System useful in such applications as surveying, docking of ships, and short-range navigation.

  15. 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.

  16. 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.

  17. Geothermal systems of the Cascade Range

    USGS Publications Warehouse

    Muffler, L.J.; Bacon, Charles R.; Duffield, W.A.

    1982-01-01

    In the central and southern Cascade Range, plate convergence is oblique, and Quaternary volcanism produces mostly basalt and mafic andesite; large andesite-dacite composite volcanoes and silicic dome fields occur in restricted areas of long-lived igneous activity. To the north, plate convergence is normal, producing widely spaced centers in which mafic lavas are minor. Most Cascade volcanoes are short-lived and unlikely to be underlain at shallow levels by large magma bodies that could support high-temperature geothermal systems. Such systems are known, however, near Meager Mountain, at Newberry Volcano, and near Lassen Peak. Persistent fumaroles occur on several major composite volcanoes, but drilling to date has been insufficient to determine whether exploitable geothermal reservoirs occur at depth. Thermal springs away from the major volcanic centers are few and generally inconspicuous. However, significant geothermal systems along and west of the Cascade Range may well be masked by abundant cold ground water.

  18. 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.

  19. Evaluation of OMV ranging and docking systems

    NASA Technical Reports Server (NTRS)

    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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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…

  5. Long range position and orientation tracking system

    SciTech Connect

    Armstrong, G.A.; Jansen, J.F.; Burks, B.L.; Bernacki, B.E.; Nypaver, D.J.

    1995-12-31

    The long range position and orientation tracking system (LRPOTS) will consist of two measurement pods, a VME-based computer system, and a detector array. The system is used to measure the position and orientation of a target that may be attached to a robotic arm, teleoperated manipulator, or autonomous vehicle. The pods have been designed to be mounted in the man-ways of the domes of the Fernald K-65 waste silos. Each pod has two laser scanner subsystems as well as lights and camera systems. One of the laser scanners will be oriented to scan in the pan direction, the other in the tilt direction. As the lasers scan across the detector array, the angles of incidence with each detector are recorded. Combining measurements from each of the four lasers yields sufficient data for a closed-form solution of the transform describing the location and orientation of the Content Mobilization System (CMS). Redundant detectors will be placed on the CMS to accommodate occlusions, to provide improved measurement accuracy, and to determine the CMS orientation.

  6. Utilization and viability of biologically-inspired algorithms in a dynamic multiagent camera surveillance system

    NASA Astrophysics Data System (ADS)

    Mundhenk, Terrell N.; Dhavale, Nitin; Marmol, Salvador; Calleja, Elizabeth; Navalpakkam, Vidhya; Bellman, Kirstie; Landauer, Chris; Arbib, Michael A.; Itti, Laurent

    2003-10-01

    computational resources. The system demonstrates the viability of biologically inspired systems in a real time tracking. In future work we plan on implementing additional biological mechanisms for cooperative management of both the sensor and processing resources in this system that include top down biasing for target specificity as well as novelty and the activity of the tracked object in relation to sensitive features of the environment.

  7. 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

  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. 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.

  10. [Viability of autologous fat grafts harvested with the Coleman technique and the tissu trans system (shippert method): a comparative study].

    PubMed

    Herold, C; Pflaum, M; Utz, P; Wilhelmi, M; Rennekampff, H-O; Vogt, P M

    2011-12-01

    Various methods for harvesting and refining autologous fat grafts have been described. One of the standard procedures, the Coleman technique, is based on manual aspiration to reduce the negative presssure and the centrifugation of the grafts. The Shippert technique uses automatic liposuction with reduced negative pressure and abstains from centifugation in order not to reduce viability of the graft by exposing it to centrifugal forces. This study intends to compare the viability of fat grafts processed with the above-mentioned methods.Fat grafts were obtained in 9 patients by using both the Tissu Trans system (Shippert technique) and the Coleman technique. To evaluate the impact of centrifugation forces, the grafts harvested with the Coleman technique were treated with standard adjustment of the centrifuge and also with doubled g-force. Viability of fat grafts was analysed with the WST-8 test and with annexin V/PI assay FACS analysis.The viability of fat grafts processed by the Coleman technique was significantly higher compared to the Shippert technique on applying the WST-8 test. Applying the annexin V/PI analysis, the viability of fat grafts was almost equal with both techniques. Whereas the fat grafts processed with the Tissu Trans system are injected without condensation, the grafts refined with the Coleman technique were concentrated 3 times by centrifugation compared to the primary liposuctioned graft volumes.The Coleman technique allows the preparation of a fat graft containing more viable cells than the Shippert technique. This is in part due to the condensation of the graft by centrifugation using the Coleman technique. The factor of condensation of the grafts harvested and refined with the Coleman technique exceeds the factor of increased fat graft viability in comparison to the Shippert technique. The Tissu Trans system is more than twice as fast and easier to use with a preferential use for large volume grafts like in breast augmentation, whereas the

  11. 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

  12. 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.

  13. 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).

  14. 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)

  15. 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).

  16. Irradiation Can Selectively Kill Tumor Cells while Preserving Erythrocyte Viability in a Co-Culture System

    PubMed Central

    Liu, Yun-Qing; Tang, Li-Hui; Wang, Yin; Wang, Lie-Ju; Zhang, Feng-Jiang; Yan, Min

    2015-01-01

    An understanding of how to safely apply intraoperative blood salvage (IBS) in cancer surgery has not yet been obtained. Here, we investigated the optimal dose of 137Cs gamma-ray irradiation for killing human hepatocarcinoma (HepG2), gastrocarcinoma (SGC7901), and colonic carcinoma (SW620) tumor cells while preserving co-cultured erythrocytes obtained from 14 healthy adult volunteers. HepG2, SGC7901, or SW620 cells were mixed into the aliquots of erythrocytes. After the mixed cells were treated with 137Cs gamma-ray irradiation (30, 50, and 100 Gy), tumor cells and erythrocytes were separated by density gradient centrifugation in Percoll with a density of 1.063 g/ml. The viability, clonogenicity, DNA synthesis, tumorigenicity, and apoptosis of the tumor cells were determined by MTT assay, plate colony formation, 5-ethynyl-2'-deoxyuridine (EdU) incorporation, subcutaneous xenograft implantation into immunocompromised mice, and annexin V/7-AAD staining, respectively. The ATP concentration, 2,3-DPG level, free Hb concentration, osmotic fragility, membrane phosphatidylserine externalization, blood gas variables, reactive oxygen species levels, and superoxide dismutase levels in erythrocytes were analyzed. We found that 137Cs gamma-ray irradiation at 50 Gy effectively inhibited the viability, proliferation, and tumorigenicity of HepG2, SGC7901, and SW620 cells without markedly damaging the oxygen-carrying ability or membrane integrity or increasing the oxidative stress of erythrocytes in vitro. These results demonstrated that 50 Gy irradiation in a standard 137Cs blood irradiator might be a safe and effective method of inactivating HepG2, SGC7901, and SW620 cells mixed with erythrocytes, which might help to safely allow IBS in cancer surgery. PMID:26018651

  17. Irradiation Can Selectively Kill Tumor Cells while Preserving Erythrocyte Viability in a Co-Culture System.

    PubMed

    Gong, Ming; Yang, Jin-Ting; Liu, Yun-Qing; Tang, Li-Hui; Wang, Yin; Wang, Lie-Ju; Zhang, Feng-Jiang; Yan, Min

    2015-01-01

    An understanding of how to safely apply intraoperative blood salvage (IBS) in cancer surgery has not yet been obtained. Here, we investigated the optimal dose of 137Cs gamma-ray irradiation for killing human hepatocarcinoma (HepG2), gastrocarcinoma (SGC7901), and colonic carcinoma (SW620) tumor cells while preserving co-cultured erythrocytes obtained from 14 healthy adult volunteers. HepG2, SGC7901, or SW620 cells were mixed into the aliquots of erythrocytes. After the mixed cells were treated with 137Cs gamma-ray irradiation (30, 50, and 100 Gy), tumor cells and erythrocytes were separated by density gradient centrifugation in Percoll with a density of 1.063 g/ml. The viability, clonogenicity, DNA synthesis, tumorigenicity, and apoptosis of the tumor cells were determined by MTT assay, plate colony formation, 5-ethynyl-2'-deoxyuridine (EdU) incorporation, subcutaneous xenograft implantation into immunocompromised mice, and annexin V/7-AAD staining, respectively. The ATP concentration, 2,3-DPG level, free Hb concentration, osmotic fragility, membrane phosphatidylserine externalization, blood gas variables, reactive oxygen species levels, and superoxide dismutase levels in erythrocytes were analyzed. We found that 137Cs gamma-ray irradiation at 50 Gy effectively inhibited the viability, proliferation, and tumorigenicity of HepG2, SGC7901, and SW620 cells without markedly damaging the oxygen-carrying ability or membrane integrity or increasing the oxidative stress of erythrocytes in vitro. These results demonstrated that 50 Gy irradiation in a standard 137Cs blood irradiator might be a safe and effective method of inactivating HepG2, SGC7901, and SW620 cells mixed with erythrocytes, which might help to safely allow IBS in cancer surgery. PMID:26018651

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. Test techniques for determining laser ranging system performance

    NASA Technical Reports Server (NTRS)

    Zagwodzki, T. W.

    1981-01-01

    Procedures and results of an on going test program intended to evaluate laser ranging system performance levels in the field as well as in the laboratory are summarized. Tests show that laser ranging system design requires consideration of time biases and RMS jitters of individual system components. All simple Q switched lasers tested were found to be inadequate for 10 centimeter ranging systems. Timing discriminators operating over a typical 100:1 dynamic signal range may introduce as much as 7 to 9 centimeters of range bias. Time interval units commercially available today are capable of half centimeter performance and are adequate for all field systems currently deployed. Photomultipliers tested show typical tube time biases of one centimeter with single photoelectron transit time jitter of approximately 10 centimeters. Test results demonstrate that NASA's Mobile Laser Ranging System (MOBLAS) receiver configuration is limiting system performance below the 100 photoelectron level.

  3. A Wide Spectral Range Reflectance and Luminescence Imaging System

    PubMed Central

    Hirvonen, Tapani; Penttinen, Niko; Hauta–Kasari, Markku; Sorjonen, Mika; Peiponen, Kai–Erik

    2013-01-01

    In this study, we introduce a wide spectral range (200–2500 nm) imaging system with a 250 μm minimum spatial resolution, which can be freely modified for a wide range of resolutions and measurement geometries. The system has been tested for reflectance and luminescence measurements, but can also be customized for transmittance measurements. This study includes the performance results of the developed system, as well as examples of spectral images. Discussion of the system relates it to existing systems and methods. The wide range spectral imaging system that has been developed is however highly customizable and has great potential in many practical applications. PMID:24233075

  4. 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.

  5. A FMCW Radar Ranging Device for the Teleoperator Maneuvering System

    NASA Technical Reports Server (NTRS)

    Mcdonald, M. W.

    1983-01-01

    A frequency-modulated continuous wave radar system is under development in the Communications Systems Branch of the Information and Electronic Systems Laboratory at Marshall Space Flight Center. The radar unit is being designed for use on the teleoperator maneuvering system. Its function is to provide millimeter-level accuracy in range and range rate measurements out to a range of thirty meters. This will facilitate soft docking with accuracy. This report is an updating of previous developments reported on this system. An innovation in the system is the utilization of a standard reference signal generated by shunting a portion of the radar energy into a shorted coaxial delay line. The regular radar target return signal is constantly compared with the reference signal to provide internal error compensation. Within a five meter range, a limit imposed by present laboratory dimensions, the radar system exhibits reliable accuracy with range error less than 0.2%.

  6. 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.

  7. 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.

  8. 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…

  9. 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…

  10. 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.

  11. Evaluating the economic viability of a material recovery system: the case of cathode ray tube glass.

    PubMed

    Gregory, Jeremy R; Nadeau, Marie-Claude; Kirchain, Randolph E

    2009-12-15

    This paper presents an analysis of the material recovery system for leaded glass from cathode ray tubes (CRTs) using a dynamic material flow analysis. In particular, the global mass flow of primary and secondary CRT glass and the theoretical capacities for using secondary CRT glass to make new CRT glass are analyzed. The global mass flow analysis indicates that the amount of new glass required is decreasing, but is much greater than the amount of secondary glass collected, which is increasing. The comparison of the ratio of secondary glass collected to the amount of new glass required from the mass flow analysis indicates that the material recovery system is sustainable for the foreseeable future. However, a prediction of the time at which the market for secondary glass will collapse due to excess capacity is not possible at the moment due to several sources of uncertainty.

  12. Temperature inversion in long-range interacting systems

    NASA Astrophysics Data System (ADS)

    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.

  13. 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.

  14. 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. PMID:26382325

  15. Quench dynamics in long-range interacting quantum systems

    NASA Astrophysics Data System (ADS)

    Gong, Zhexuan

    2016-05-01

    A distinctive feature of atomic, molecular, and optical systems is that interactions between particles are often long-ranged. Control techniques from quantum optics often allow one to tune the pattern of these long-range interactions, creating an entirely new degree of freedom, absent in typical condensed matter systems. These tunable long-range interactions can result in very different far-from-equilibrium dynamics compared to systems with only short-range interactions. In the first half of the talk, I will describe how very general types of long-range interactions can qualitatively change the entanglement and correlation growth shortly after a quantum quench. In the second half of the talk I will show that, at longer times, long-range interactions can lead to exotic quasi-stationary states and dynamical phase transitions. These theoretical ideas have been explored in recent trapped-ion experiments, and connections to these experiments will be emphasized in both parts of the talk.

  16. 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.

  17. 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

  18. Assessing the viability of microsponges as gastro retentive drug delivery system of curcumin: optimization and pharmacokinetics.

    PubMed

    Arya, Priyanka; Pathak, Kamla

    2014-01-01

    The work was aimed to validate the gastroretentive potential of microsponges via optimization of targeted floating curcumin microsponges for improved site specific absorption for gastric cancer Modified quasi emulsion solvent diffusion method was used to formulate microsponges using 3(2) full factorial design. The effect of different levels of ethyl cellulose and polyvinyl alcohol concentration, selected as independent variables was determined on the % entrapment efficiency, % buoyancy and % cumulative drug release. Modified rosette rise apparatus was used for in vitro release and the release data best fitted Higuchi's model and mechanism of drug release was diffusion (n). The optimized formulation (MS5) demonstrated favourable % entrapment efficiency (90.7 ± 1.7), % buoyancy (82.0 ± 2.0) and % cumulative drug release (85.2 ± 1.07) with maximum desirability factor of 0.816. SEM revealed spherical and porous microsponges. DSC confirmed molecular dispersion of the drug in the microsponges polymeric matrix. DRIFT revealed no chemical interaction between the drug and polymer used. The in vitro permeation of curcumin through gastric mucin gel layer affirmed the capability of microsponges to deliver drug across mucin r and reach the target site to treat gastric cancer. Anticancer oral dose of microsponges was calculated as 50mg by cytotoxicity assay in human cancer cell line KB. The pharmacokinetic evaluation of MS5 in rabbits revealed 10-fold increase in bioavailability as compared to native curcumin, demonstrated the superiority of microsponges over native curcumin as gastro retentive drug delivery system. This study presents a new approach based on floating ability of microsponges for treatment of gastric cancer.

  19. 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

  20. 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.

  1. 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

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

    PubMed

    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.

  3. 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.

  4. 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.

  5. Range accuracy analysis of streak tube imaging lidar systems

    NASA Astrophysics Data System (ADS)

    Ye, Guangchao; Fan, Rongwei; Chen, Zhaodong; Yuan, Wei; Chen, Deying; He, Ping

    2016-02-01

    Streak tube imaging lidar (STIL) is an active imaging system that has a high range accuracy and a wide range gate with the use of a pulsed laser transmitter and streak tube receiver to produce 3D range images. This work investigates the range accuracy performance of STIL systems based on a peak detection algorithm, taking into account the effects of blurring of the image. A theoretical model of the time-resolved signal distribution, including the static blurring width in addition to the laser pulse width, is presented, resulting in a modified range accuracy analysis. The model indicates that the static blurring width has a significant effect on the range accuracy, which is validated by both the simulation and experimental results. By using the optimal static blurring width, the range accuracies are enhanced in both indoor and outdoor experiments, with a stand-off distance of 10 m and 1700 m, respectively, and corresponding, best range errors of 0.06 m and 0.25 m were achieved in a daylight environment.

  6. 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

  7. 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.

  8. Method for increased detection range in IR warning systems

    NASA Astrophysics Data System (ADS)

    Arad, Eyal; Roit, Paula

    2014-10-01

    Target range of Infra-Red (IR) point target warning systems, is determined by the effective entrance pupil diameter of the system's optics. In addition, the system's F/# is usually set by the detector (as in cryogenically cooled detectors). Moreover, the detector's aspect-ratio usually set the field proportions (5:4, 4:3, etc.).Thus for example, for wide angle systems, the horizontal coverage angle is usually determining the vertical one. We propose a system including anamorphic optics that changes the effective focal length of each axis independently, keeping the detector's given F/#, thus changing the effective aperture. Since the range is approximately proportional to the effective aperture, we achieve a range improvement of the square-root of the vertical and horizontal focal length ratio, reducing the vertical coverage accordingly. In this way, we make the field proportions less dependent of the detector's proportions. Using this method, it is made possible for wide angle systems to improve target detection range on the expense of the vertical coverage, without changing the horizontal coverage or increasing the amount of detection units (e.g. FLIRs).

  9. Hybrid gesture recognition system for short-range use

    NASA Astrophysics Data System (ADS)

    Minagawa, Akihiro; Fan, Wei; Katsuyama, Yutaka; Takebe, Hiroaki; Ozawa, Noriaki; Hotta, Yoshinobu; Sun, Jun

    2012-03-01

    In recent years, various gesture recognition systems have been studied for use in television and video games[1]. In such systems, motion areas ranging from 1 to 3 meters deep have been evaluated[2]. However, with the burgeoning popularity of small mobile displays, gesture recognition systems capable of operating at much shorter ranges have become necessary. The problems related to such systems are exacerbated by the fact that the camera's field of view is unknown to the user during operation, which imposes several restrictions on his/her actions. To overcome the restrictions generated from such mobile camera devices, and to create a more flexible gesture recognition interface, we propose a hybrid hand gesture system, in which two types of gesture recognition modules are prepared and with which the most appropriate recognition module is selected by a dedicated switching module. The two recognition modules of this system are shape analysis using a boosting approach (detection-based approach)[3] and motion analysis using image frame differences (motion-based approach)(for example, see[4]). We evaluated this system using sample users and classified the resulting errors into three categories: errors that depend on the recognition module, errors caused by incorrect module identification, and errors resulting from user actions. In this paper, we show the results of our investigations and explain the problems related to short-range gesture recognition systems.

  10. 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. PMID:23764214

  11. 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.

  12. A digital IF simulator for FM ranging systems

    NASA Astrophysics Data System (ADS)

    Bartlett, M. C.; Johnson, R. C.

    1980-03-01

    A digital intermediate frequency signal simulator (DIFSS) which is useful for testing many periodically modulated FM ranging systems is described. The DIFSS digitally computes the IF signal angle using angle tables stored in EPROM's and generates the cosine of the angle with a cosine PROM and D/A converter. Target delay time tau and doppler frequency can be varied as desired for static tests or dynamic target trajectories. The simulator is useful for testing real-time hardware or for testing ambiguous ranging system responses in a scaled-time mode.

  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. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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.

  19. 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. PMID:27527766

  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. Comment on "Temperature inversion in long-range interacting systems"

    NASA Astrophysics Data System (ADS)

    Dumin, Yurii V.

    2016-06-01

    In the recent paper by Teles et al. [Phys. Rev. E 92, 020101 (2015)], 10.1103/PhysRevE.92.020101, it was suggested that the inversed temperature profiles in various astrophysical objects—ranging from the solar corona to the interstellar molecular clouds—can be explained by the specific features of relaxation in the long-range interacting systems. Here, we show that this mechanism can really work in the self-gravitating interstellar gaseous clouds; but it is irrelevant in the solar (and stellar) coronas where stratification of density is produced by the external gravitational field.

  2. Comment on "Temperature inversion in long-range interacting systems".

    PubMed

    Dumin, Yurii V

    2016-06-01

    In the recent paper by Teles et al. [Phys. Rev. E 92, 020101 (2015)]PRESCM1539-375510.1103/PhysRevE.92.020101, it was suggested that the inversed temperature profiles in various astrophysical objects-ranging from the solar corona to the interstellar molecular clouds-can be explained by the specific features of relaxation in the long-range interacting systems. Here, we show that this mechanism can really work in the self-gravitating interstellar gaseous clouds; but it is irrelevant in the solar (and stellar) coronas where stratification of density is produced by the external gravitational field.

  3. Comment on "Temperature inversion in long-range interacting systems".

    PubMed

    Dumin, Yurii V

    2016-06-01

    In the recent paper by Teles et al. [Phys. Rev. E 92, 020101 (2015)]PRESCM1539-375510.1103/PhysRevE.92.020101, it was suggested that the inversed temperature profiles in various astrophysical objects-ranging from the solar corona to the interstellar molecular clouds-can be explained by the specific features of relaxation in the long-range interacting systems. Here, we show that this mechanism can really work in the self-gravitating interstellar gaseous clouds; but it is irrelevant in the solar (and stellar) coronas where stratification of density is produced by the external gravitational field. PMID:27415395

  4. 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.

  5. Local cost sharing in Bamako Initiative systems in Benin and Guinea: assuring the financial viability of primary health care.

    PubMed

    Soucat, A; Levy-Bruhl, D; Gbedonou, P; Drame, K; Lamarque, J P; Diallo, S; Osseni, R; Adovohekpe, P; Ortiz, C; Debeugny, C; Knippenberg, R

    1997-06-01

    The fourth in a series of five, this article presents and analyses data on cost recovery and community cost-sharing, two key aspects of the Bamako Initiative which have been implemented in Benin and Guinea since 1986. The data come from approximately 400 health centres and result from the six-monthly monitoring sessions conducted from 1989 to 1993. Community involvement in the financing of local operating costs in the two national scale programmes is also described. In Benin and Guinea, a user fee system generates the community financed revenue with the aim of covering local operating costs including drugs. Health worker salaries remain the responsibility of the government and donor funding covers vaccine and investment costs. Village health committees manage and control resources and revenue. The community is also involved in decision making, strategy definition and quality control. In Benin in 1993, community financing revenue amounted to about US$0.6 per capita per year and generally covered all local recurrent non salary costs except vaccines and left a surplus. Although total costs and revenues were slightly lower in Guinea for the same period, over-all user fee revenue (around US$0.3 per capita per year) covered local recurrent costs (not including salaries or vaccines). A comparison of costs and revenue between regions and individual health centres revealed important differences in cost recovery ratios. In Benin, some centres recovered more than twice the local costs targeted for community financing. Twenty-five per cent of centres in Guinea did not manage to cover their designated local recurrent costs. The longitudinal analysis showed that the level of cost recovery remained stable over time even as preventive care (and especially EPI) coverage rose significantly. To better understand the most important characteristics affecting cost recovery levels, best performing health centres in terms of cost-recovery levels in 1993 were compared to worst performing

  6. 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.

  7. 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.

  8. 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.

  9. Integrated radar-camera security system: range test

    NASA Astrophysics Data System (ADS)

    Zyczkowski, M.; Szustakowski, M.; Ciurapinski, W.; Karol, M.; Markowski, P.

    2012-06-01

    The paper presents the test results of a mobile system for the protection of large-area objects, which consists of a radar and thermal and visual cameras. Radar is used for early detection and localization of an intruder and the cameras with narrow field of view are used for identification and tracking of a moving object. The range evaluation of an integrated system is presented as well as the probability of human detection as a function of the distance from radar-camera unit.

  10. 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

  11. 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.

  12. 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. PMID:25161106

  13. 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.

  14. 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.

  15. 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.

  16. 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. PMID:26628178

  17. 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.

  18. Short-range biological standoff detection system (SR-BSDS)

    NASA Astrophysics Data System (ADS)

    Suliga, William; Burnham, Ralph L.; Deely, Timothy; Gavert, William; Pronko, Mark S.; Verdun, Gustavo; Verdun, Horacio R.; Cannaliato, V. James; Ginley, William J.; Hyttinen, Larry; Strawbridge, John B.

    1999-11-01

    Fibertek is currently under contract to the US Army Soldier and Biological Chemical Command (SBCCOM) at Aberdeen Proving Ground, MD to develop a multi-wavelength lidar system. Under this effort, Fibertek will deliver a system that is capable of detecting the presence of biological aerosols. The SR-BSDS has successfully demonstrated the ability to detect and track a biological aerosol cloud while discriminating between biological and non-biological aerosols and hard targets. The SR-BSDS is an active standoff detection system with both ultraviolet (UV) and infrared (IR) capability. The UV wavelengths can provide near real time detection and ranging of a particulate cloud with demonstrated discrimination capability. Recent enhancements to the IR capability extended the cloud detection range and acquisition capability as well as providing an autonomous operation mode of operation. The SR-BSDS can be operated in one of two modes, manual or autonomous. In the manual mode the operator selects the desired scan field of view, resolution, wavelength, and degree of pulse coadding, then instructs the system to start scanning. The system will monitor its own performance and display information to the operator to indicate proper operation. The system will monitor cloud data and warn the operator when the sensor is aimed at an aerosol of interest. If a biological cloud of interest is found, an audible alarm will sound, and the operator can examine cloud imagery while the system continues to automatically monitor and track all clouds in the field-of-view. The scanning parameters can also be changed easily upon aerosol detection, if desired. In the autonomous mode, the operator selects the desired scan field of view. The system automatically scans for aerosol clouds with the IR beam. This is accomplished in a rapid, single pulse laser firing mode. Once a cloud with specified characteristics is acquired, the system automatically switches over to an UV beam for discrimination

  19. UAV sensor systems for close-range operations

    NASA Astrophysics Data System (ADS)

    Larroque, Clement-Serge; Thompson, Karl S.; Hickman, Duncan

    2002-07-01

    Although UAV systems have received much interest over the last few years, much of this has focused on either relatively large platforms with complex on-board equipment, or micro systems (typically 6' in every dimension). The operational use of low-cost lightweight UAVs as over-the- hill reconnaissance systems is a new concept offering additional flexibility, providing local knowledge and helping maintain operational tempo. An extensive modeling trade-off study has been performed for different sensor technologies and combinations. The model considered configurations including cooled and uncooled IR sensors, visible-band CCD sensors and image intensifiers. These mathematical models provide an evaluation of sensor performance for both navigation and the gathering of reconnaissance imagery, through Resolution Elements calculations (Johnson criteria) and Signal-to-Noise Ratios. Based upon this analysis, a system specification is presented that exploits next generation sensor technologies. Results obtained from a number of UAV trials are reported and used in order to provide model verification and validation of both the operational concepts and the sensor system modeling activities. Considering the sensor system itself, the low-altitude close-range environment ensures high ground resolved distance and signal-to-noise ratios, with low-cost sensors. Coupled with up-to-date image processing software, the imagery provided directly to the section-level units via a simple standard image interface allows a reduction of time response. Finally, future modeling and trials activities are discussed in the framework of the lightweight UAV system roadmap.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. A magnetic suspension system with a large angular range

    NASA Astrophysics Data System (ADS)

    Britcher, Colin P.; Ghofrani, Mehran

    1993-07-01

    In order to explore and develop technology required for the magnetic suspension of objects over large ranges of orientation, a small-scale laboratory system, the large-angle magnetic suspension test fixture (LAMSTF) has been constructed at NASA Langley Research Center. This apparatus falls into the category of large-gap, actively stabilized magnetic levitation systems. The hardware comprises five conventional electromagnets in a circular arrangement, each driven from a separate bipolar power amplifier. Electromagnet currents are commanded by a digital control system, implemented on a microcomputer, which in turn derives the position and attitude of the suspended element from an infrared optical system. The suspended element is a cylindrical, axially magnetized, permanent magnet core, within an aluminum tube. The element is ``levitated'' by repulsive forces, with its axis horizontal, 0.1 m above the top plane of the electromagnet conductor. The element is stabilized in five degrees-of-freedom, with rotation about the cylinder axis not controlled. By mechanical rotation of the sensor assembly, the suspended element can be made to undergo a full 360° rotation about the vertical axis. The controller accommodates the changes in magnetic coupling between the electromagnets and the suspended element by real-time adaptation of a decoupling matrix. This report presents a review of the background to the problem of magnetic suspension over large ranges of orientation. Next, the design and operation procedures adopted for LAMSTF, and the system hardware are described. Finally, some performance measurements are shown, together with illustration that the major design objective—the 360° rotation, has been accomplished.

  5. 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.

  6. A dual chamber Gregorian subreflector system for compact range applications

    NASA Astrophysics Data System (ADS)

    Pistorius, Carl W. I.; Clerici, Giancarlo C.; Burnside, Walter D.

    1989-03-01

    A dual-chamber compact range configuration is proposed wherein the main reflector and target zone are located in the main chamber and an oversized Gregorian subreflector and associated feed assemblies in the other. The chambers are isolated by an absorber fence except for a small coupling aperture which is used to transmit signals between them. The absorber fence prevents diffraction by the subreflector and spillover by the feed from illuminating the main reflector and target zone. System performance is analyzed with and without the absorber fence to show how the coupling aperture should be shaped to minimize diffractions.

  7. A dual chamber Gregorian subreflector system for compact range applications

    NASA Technical Reports Server (NTRS)

    Pistorius, Carl W. I.; Clerici, Giancarlo C.; Burnside, Walter D.

    1989-01-01

    A dual-chamber compact range configuration is proposed wherein the main reflector and target zone are located in the main chamber and an oversized Gregorian subreflector and associated feed assemblies in the other. The chambers are isolated by an absorber fence except for a small coupling aperture which is used to transmit signals between them. The absorber fence prevents diffraction by the subreflector and spillover by the feed from illuminating the main reflector and target zone. System performance is analyzed with and without the absorber fence to show how the coupling aperture should be shaped to minimize diffractions.

  8. Long-range position and orientation tracking system

    SciTech Connect

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

    1995-12-31

    The long-range position and orientation tracking system will consist of two measurement pods, a VME-based computer system, and a detector array. The system is used to measure the position and orientation of a target that may be attached to a robotic arm, teleoperated manipulator, or autonomous vehicle. The pods have been designed to be mounted in the manways of the domes of the Fernald K-65 waste silos. Each pod has two laser scanner subsystems as well as lights and camera systems. One of the laser scanners will be oriented to scan in the pan direction, the other in the tilt direction. As the lasers scan across the detector array, the angles of incidence with each detector are recorded. Combining measurements from each of the four lasers yields sufficient data for a closed-form solution of the transform describing the location and orientation of the content mobilization system (CMS). Redundant detectors will be placed on the CMS to accommodate occlusions, to provide improved measurement accuracy, and to determine the CMS orientation.

  9. 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.

  10. 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.

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

    PubMed

    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

  12. 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.

  13. 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.

  14. 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

  15. 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.

  16. Linear optical coherence tomography system with extended measurement range.

    PubMed

    Koch, Peter; Hellemanns, Volker; Hüttmann, Gereon

    2006-10-01

    Optical coherence tomography (OCT) sensors traditionally use scanning optical delay lines with moving parts and a single detector. OCT systems with a linear detector array (linear OCT or L-OCT) are simple and robust, but a detector with approximately 10,000 pixels is needed for an imaging depth of 2mm, which is necessary for most biomedical applications. We present a new optical setup for L-OCT with an increased measurement range. An additional grating performs a reduction of the spatial frequencies of the fringe pattern on the detector without loss in the signal-to-noise ratio, so the signal can be sampled with a minimal number of pixels. The theory for this approach is addressed and the first measurements are presented. PMID:16969410

  17. 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.

  18. 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.

  19. 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.

  20. Long-Range Gaze Tracking System for Large Movements.

    PubMed

    Cho, Dong-Chan; Kim, Whoi-Yul

    2013-12-01

    In the vision-based remote gaze tracking systems, the most challenging topics are to allow natural movement of a user and to increase the working volume and distance of the system. Several eye gaze estimation methods considering the natural movement of a user have been proposed. However, their working volume and distance are narrow and close. In this paper, we propose a novel 2-D mapping-based gaze estimation method that allows large-movement of user. Conventional 2-D mapping-based methods utilize mapping function between calibration points on the screen and pupil center corneal reflection (PCCR) vectors obtained in user calibration step. However, PCCR vectors and their associated mapping function are only valid at or near to the position where the user calibration is performed. The proposed movement mapping function, complementing the user's movement, estimates scale factors between two PCCR vector sets: one obtained at the user calibration position and another obtained at the new user position. The proposed system targets a longer range gaze tracking which operates from 1.4 to 3 m. A narrow-view camera mounted on a pan and tilt unit is used by the proposed system to capture high-resolution eye image, providing a wide and long working volume of about 100 cm × 40 cm × 100 cm. The experimental results show that the proposed method successfully compensated the poor performance due to user's large movement. Average angular error was 0.8° and only 0.07° of angular error was increased while the user moved around 81 cm. PMID:23751947

  1. 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.

  2. Antioxidant N-Acetylcysteine and Glutathione Increase the Viability and Proliferation of MG63 Cells Encapsulated in the Gelatin Methacrylate/VA-086/Blue Light Hydrogel System.

    PubMed

    Lin, Chih-Hsin; Lin, Kai-Fung; Mar, Kwei; Lee, Shyh-Yuan; Lin, Yuan-Min

    2016-08-01

    Photoencapsulation of cells inside a hydrogel system can provide a suitable path to establish a gel in situ for soft tissue regeneration applications. However, the presence of photoinitiators and blue or UV light irradiation can result in cell damage and an increase of reactive oxygen species. We here evaluate the benefits of an antioxidant pretreatment on the photoencapsulated cells. We study this by evaluating proliferation and viability of MG63 cells, which we combined with a gelatin methacrylate (GelMA) hydrogel system, using the photoinitiator, VA-086, cured with 440 nm blue light. We found that blue light irradiation as well as the presence of 1% VA-086 reduced MG63 cell proliferation rates. Adding a short pretreatment step to the MG63 cells, consisting of the antioxidant molecules N-acetylcysteine (NAC) and reduced glutathione (GSH), and optimizing the GelMA encapsulation steps, we found that both NAC and GSH pretreatments of MG63 cells significantly increased both proliferation and viability of the cells, when using a 15% GelMA hydrogel, 1% VA-086, and 1-min blue light exposure. These findings suggest that the use of antioxidant pretreatment can counteract the negative presence of the photoinitiators and blue light exposure and result in a suitable environment for photoencapsulating cells in situ for tissue engineering and soft tissue applications.

  3. 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).

  4. 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.

  5. 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.

  6. Viability of human adenovirus from hospital fomites.

    PubMed

    Ganime, Ana Carolina; Carvalho-Costa, Filipe A; Santos, Marisa; Costa Filho, Rubens; Leite, José Paulo G; Miagostovich, Marize P

    2014-12-01

    The monitoring of environmental microbial contamination in healthcare facilities may be a valuable tool to determine pathogens transmission in those settings; however, such procedure is limited to bacterial indicators. Viruses are found commonly in those environments and are rarely used for these procedures. The aim of this study was to assess distribution and viability of a human DNA virus on fomites in an Adult Intensive Care Unit of a private hospital in Rio de Janeiro, Brazil. Human adenoviruses (HAdV) were investigated in 141 fomites by scraping the surface area and screening by quantitative PCR (qPCR) using TaqMan® System (Carlsbad, CA). Ten positive samples were selected for virus isolation in A549 and/or HEp2c cell lines. A total of 63 samples (44.7%) were positive and presented viral load ranging from 2.48 × 10(1) to 2.1 × 10(3) genomic copies per millilitre (gc/ml). The viability was demonstrated by integrated cell culture/nested-PCR in 5 out of 10 samples. Nucleotide sequencing confirmed all samples as HAdV and characterized one of them as specie B, serotype 3 (HAdV-3). The results indicate the risk of nosocomial transmission via contaminated fomites and point out the use of HAdV as biomarkers of environmental contamination.

  7. Triptycenes: a novel synthetic class of bifunctional anticancer drugs that inhibit nucleoside transport, induce DNA cleavage and decrease the viability of leukemic cells in the nanomolar range in vitro.

    PubMed

    Perchellet, E M; Magill, M J; Huang, X; Brantis, C E; Hua, D H; Perchellet, J P

    1999-09-01

    In contrast to their inactive parent compound triptycene (code name TT0), several triptycene (TT) analogs (code names TT1 to TT13), most of them new compounds, were synthesized and shown to prevent L1210 leukemic cells from synthesizing macromolecules and growing in vitro. The most potent rigid tetracyclic quinones synthesized so far are TT2 and its C2-brominated derivative, TT13. The antitumor activity of TT2 has been compared to that of daunomycin (DAU), a clinically valuable anthracycline antibiotic which is structurally different from TT2 but also contains a quinone moiety. TT2 inhibits the proliferation (IC50: 300 nM at day 2 and 150 nM at day 4) and viability (IC50: 250 nM at day 2 and 100 nM at day 4) of L1210 cells to the same maximal degree as DAU, suggesting that the cytostatic and cytotoxic activities of TT2 are a combination of drug concentration and duration of drug exposure. Since TT2 does not increase the mitotic index of L1210 cells at 24 h like vincristine, it is unlikely to be an antimitotic drug that disrupts microtubule dynamics. Like DAU, a 1.5-3 h pretreatment with TT2 is sufficient to inhibit the rates of DNA, RNA and protein syntheses determined over 30-60 min periods of pulse-labeling in L1210 cells in vitro (IC50: 6 microM). In contrast to DAU, which is inactive, a 15 min pretreatment with TT2 has the advantage of also inhibiting the cellular transport of nucleosides occuring over a 30 s period in vitro (IC50: 6 microM), suggesting that TT2 prevents the incorporation of [3H]thymidine into DNA because it rapidly blocks the uptake of [3H]thymidine by the tumor cells. After 24 h, TT2 induces as much DNA cleavage as camptothecin and DAU, two anti-cancer drugs producing DNA strand breaks and known to respectively inhibit DNA topoisomerase I and II activities. Interestingly, the abilities of TT2 to block nucleoside transport, inhibit DNA synthesis and induce DNA fragmentation are irreversible upon drug removal, suggesting that this compound may

  8. Microcanonical Analysis on a System with Long-Range Interactions

    NASA Astrophysics Data System (ADS)

    Hou, Ji-Xuan; Yu, Xu-Chen; Hou, Jing-Min

    2016-09-01

    We study a long-range interacting spin chain placed in a staggered magnetic field using microcanonical approach and obtain the global phase diagram. We find that this model exhibits both first order phase transition and second order phase transition separated by a tricritical point, and temperature jump can be observed in the first order phase transition.

  9. 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

  10. Fusion of a variable baseline system and a range finder.

    PubMed

    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

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Towards an Automated Acoustic Detection System for Free Ranging Elephants

    PubMed Central

    Zeppelzauer, Matthias; Hensman, Sean; Stoeger, Angela S.

    2015-01-01

    The human-elephant conflict is one of the most serious conservation problems in Asia and Africa today. The involuntary confrontation of humans and elephants claims the lives of many animals and humans every year. A promising approach to alleviate this conflict is the development of an acoustic early warning system. Such a system requires the robust automated detection of elephant vocalizations under unconstrained field conditions. Today, no system exists that fulfills these requirements. In this paper, we present a method for the automated detection of elephant vocalizations that is robust to the diverse noise sources present in the field. We evaluate the method on a dataset recorded under natural field conditions to simulate a real-world scenario. The proposed method outperformed existing approaches and robustly and accurately detected elephants. It thus can form the basis for a future automated early warning system for elephants. Furthermore, the method may be a useful tool for scientists in bioacoustics for the study of wildlife recordings. PMID:25983398

  17. 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.

  18. 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

  19. 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.

  20. Protein-protein interactions within the Fatty Acid Synthase-II system of Mycobacterium tuberculosis are essential for mycobacterial viability.

    PubMed

    Veyron-Churlet, Romain; Guerrini, Olivier; Mourey, Lionel; Daffé, Mamadou; Zerbib, Didier

    2004-12-01

    Despite the existence of efficient chemotherapy, tuberculosis remains a leading cause of mortality worldwide. New drugs are urgently needed to reduce the potential impact of the emergence of multidrug-resistant strains of the causative agent Mycobacterium tuberculosis (Mtb). The front-line antibiotic isoniazid (INH), and several other drugs, target the biosynthesis of mycolic acids and especially the Fatty Acid Synthase-II (FAS-II) elongation system. This biosynthetic pathway is essential and specific for mycobacteria and still represents a valuable system for the search of new anti-tuberculous agents. Several data, in the literature, suggest the existence of protein-protein interactions within the FAS-II system. These interactions themselves might serve as targets for a new generation of drugs directed against Mtb. By using an extensive in vivo yeast two-hybrid approach and in vitro co-immunoprecipitation, we have demonstrated the existence of both homotypic and heterotypic interactions between the known components of FAS-II. The condensing enzymes KasA, KasB and mtFabH interact with each other and with the reductases MabA and InhA. Furthermore, we have designed and constructed point mutations of the FAS-II reductase MabA, able to disrupt its homotypic interactions and perturb the interaction pattern of this protein within FAS-II. Finally, we showed by a transdominant genetic approach that these mutants are dominant negative in both non-pathogenic and pathogenic mycobacteria. These data allowed us to draw a dynamic model of the organization of FAS-II. They also represent an important step towards the design of a new generation of anti-tuberculous agents, as being inhibitors of essential protein-protein interactions. PMID:15554959

  1. The three-boson system with short-range interactions

    NASA Astrophysics Data System (ADS)

    Bedaque, P. F.; Hammer, H.-W.; van Kolck, U.

    1999-02-01

    We discuss renormalization of the non-relativistic three-body problem with short-range forces. The problem is non-perturbative at momenta of the order of the inverse of the two-body scattering length. An infinite number of graphs must be summed, which leads to a cutoff dependence that does not appear in any order in perturbation theory. We argue that this cutoff dependence can be absorbed in one local three-body force counterterm and compute the running of the three-body force with the cutoff. This allows a calculation of the scattering of a particle and the two-particle bound state if the corresponding scattering length is used as input. We also obtain a model-independent relation between binding energy of a shallow three-body bound state and this scattering length. We comment on the power counting that organizes higher-order corrections and on relevance of this result for the effective field theory program in nuclear and molecular physics.

  2. 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.

  3. 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.

  4. L-DOPA modulates cell viability through the ERK-c-Jun system in PC12 and dopaminergic neuronal cells.

    PubMed

    Park, Keun Hong; Shin, Keon Sung; Zhao, Ting Ting; Park, Hyun Jin; Lee, Kyung Eun; Lee, Myung Koo

    2016-02-01

    L-DOPA causes neurotoxicity by modulating the Epac-ERK system in PC12 cells. This study investigated the effects of a single treatment with L-DOPA and multiple treatments with L-DOPA (MT-LD) on ERK1/2 and JNK1/2-c-Jun systems. In PC12 cells, a toxic L-DOPA concentration (200 μM) induced sustained ERK1/2 and JNK1/2 phosphorylation that was inhibited by the Epac inhibitor brefeldin A, but not by the PKA inhibitor H89. This ERK1/2 and JNK1/2 phosphorylation was also inhibited by ERK1/2 (U0126) and JNK1/2 (SP600125) inhibitors, respectively, but sustained ERK1/2 phosphorylation was not affected by JNK1/2 phosphorylation. A non-toxic L-DOPA concentration (20 μM) induced c-Jun phosphorylation (Ser73) via transient ERK1/2 phosphorylation, whereas the toxic L-DOPA concentration induced c-Jun phosphorylation (Ser63) and c-Jun expression via Epac-sustained ERK1/2-JNK1/2 phosphorylation, which then enhanced cleaved caspase-3 expression. MT-LD (20 μM) initially enhanced c-Jun phosphorylation (Ser73) (for 1-4 days), but later (5-6 days) induced c-Jun phosphorylation (Ser63) and c-Jun expression. In the 6-hydroxydopamine-lesioned rat model of Parkinson's disease, L-DOPA administration (10 mg/kg) protected against neurotoxicity through c-Jun phosphorylation (Ser73) for 1-2 weeks. However, L-DOPA administration (10 or 30 mg/kg) showed neurotoxicity through c-Jun phosphorylation (Ser63) and c-Jun expression via ERK1/2 phosphorylation for 3-4 weeks. Thus, in PC12 cells, non-toxic L-DOPA treatment maintained cell survival through c-Jun phosphorylation (Ser73). By contrast, toxic L-DOPA treatment or MT-LD (20 μM) induced c-Jun phosphorylation (Ser63) and c-Jun expression via Epac-dependent sustained ERK1/2 and JNK1/2 phosphorylation, which subsequently led to cell death. These results were validated by those obtained after long-term L-DOPA administration in a rat model of Parkinson's disease. Our data indicate that L-DOPA causes neurotoxicity via the ERK1/2-c-Jun system in

  5. Long-range planning for advanced European space transportation systems

    NASA Astrophysics Data System (ADS)

    Reichert, Rudi G.

    Begining in 1988, The West German Ministry for Research and Technology will conduct a five-year National Hypersonic Technology Program aimed at the development of critical components for the airbreathing, two-reusable stage transatmospheric vehicle concept designated 'Saenger'. Saenger will be alternatively capable of launching 15-ton unmanned payloads into LEO with its 'Cargus' second stage, or 5-ton manned payloads into LEO with its 'Horus' second stage. The focus of these efforts is the definition of the scramjet-based propulsion system, followed in importance by aerothermodynamic studies of the configuration and the development of suitable structures and materials.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. Results of the long range position-determining system tests. [Field Army system

    NASA Technical Reports Server (NTRS)

    Rhode, F. W.

    1973-01-01

    The long range position-determining system (LRPDS) has been developed by the Corps of Engineers to provide the Field Army with a rapid and accurate positioning capability. The LRPDS consists of an airborne reference position set (RPS), up to 30 ground based positioning sets (PS), and a position computing central (PCC). The PCC calculates the position of each PS based on the range change information provided by each Set. The positions can be relayed back to the PS again via RPS. Each PS unit contains a double oven precise crystal oscillator. The RPS contains a Hewlett-Packard cesium beam standard. Frequency drifts and off-sets of the crystal oscillators are taken in account in the data reduction process. A field test program was initiated in November 1972. A total of 54 flights were made which included six flights for equipment testing and 48 flights utilizing the field test data reduction program. The four general types of PS layouts used were: short range; medium range; long range; tactical configuration. The overall RMS radial error of the unknown positions varied from about 2.3 meters for the short range to about 15 meters for the long range. The corresponding elevation RMS errors vary from about 12 meters to 37 meters.

  12. The Development of a Digital Processing System for Accurate Range Determinations. [for Teleoperator Maneuvering Systems

    NASA Technical Reports Server (NTRS)

    Pujol, A., Jr.

    1983-01-01

    The development of an accurate close range (from 0.0 meters to 30.0 meters) radar system for Teleoperator Maneuvering Systems (TMS) is discussed. The system under investigation is a digital processor that converts incoming signals from the radar system into their related frequency spectra. Identification will be attempted by correlating spectral characteristics with accurate range determinataions. The system will utilize an analog to digital converter for sampling and converting the signal from the radar system into 16-bit digital words (two bytes) for RAM storage, data manipulations, and computations. To remove unwanted frequency components the data will be retrieved from RAM and digitally filtered using large scale integration (LSI) circuits. Filtering will be performed by a biquadratic routine within the chip which carries out the required filter algorithm. For conversion to a frequency spectrum the filtered data will be processed by a Fast Fourier Transform chip. Analysis and identification of spectral characteristics for accurate range determinations will be made by microcomputer computations.

  13. Viability studies on actinomycetes.

    PubMed

    Taddei, A; Tremarias, M M; Hartung de Capriles, C

    Eighty-nine Actinomycetes strains were tested for their viability, morphological and physiological characteristics after being kept under paraffin oil overlay and distilled water for a period between 10-30 years. Most of the studied strains belong to the "Lorenzo De Montemayor" collection. Almost all the recovered strains were 28-30 years old and had never been subcultured since the paraffin oil was overlaid. 71.4% of viable Streptomycetes strains had been kept on Sabouraud-dextrose agar and 28.6% were kept on Negroni and Bonfiglioli-medium. Streptomyces violaceusruber produced its characteristic pigment even after 28 years under these conditions. All of the recovered strains were tested for their biological activity, but only Streptomyces lavendulae showed growth-inhibition against Staphylococcus aureus and Bacillus subtilis.

  14. 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

  15. 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. PMID:24489790

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

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 14 2013-04-01 2013-04-01 false Election of Class Life Asset Depreciation Range... Election of Class Life Asset Depreciation Range System (ADR). (a) Elections filed before February 1, 1972... election will be treated as an election under the Class Life Asset Depreciation Range System (ADR)...

  18. 26 CFR 12.4 - Election of Class Life Asset Depreciation Range System (ADR).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 14 2014-04-01 2013-04-01 true Election of Class Life Asset Depreciation Range... Election of Class Life Asset Depreciation Range System (ADR). (a) Elections filed before February 1, 1972... election will be treated as an election under the Class Life Asset Depreciation Range System (ADR)...

  19. 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.

  20. 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.

  1. Geoscience Laser Ranging System - Estimated accuracy of geodetic parameters and their dependence on system characteristics

    NASA Technical Reports Server (NTRS)

    Cohen, Steven C.; Chinn, Douglas S.; Dunn, Peter J.

    1990-01-01

    Covariance analysis of the performance of the Geoscience Laser Ranging System (GLRS) indicates that three-dimensional relative positions can be recovered to an accuracy of several millimeters over spatial scales from a few kilometers to several hundred kilometers and over temporal scales as short as several days. The key factors influencing the accuracy are range noise, number of targets and their locations, system pointing capability, dwell time on the targets, orbital geometry, and gravity field uncertainties. Based on the present trade-off studies, GLRS is designed to provide range measurements with 10 mm or better accuracy, fire at a rate of 40 pulses-per-second, point over a cone extending to 50 deg from nadir, and operate with a dwell time on individual targets of 2 s or less. Given a strain rate of 10 to the -14th/s, estimated GLRS accuracy parameters suggest that the deformation can be detected in less than a month if it extends over 100 km and in less than 6 months if it extends over 10 km.

  2. 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

  3. 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.

  4. xCELLigence system for real-time label-free monitoring of growth and viability of cell lines from hematological malignancies.

    PubMed

    Martinez-Serra, Jordi; Gutierrez, Antonio; Muñoz-Capó, Saúl; Navarro-Palou, María; Ros, Teresa; Amat, Juan Carlos; Lopez, Bernardo; Marcus, Toni F; Fueyo, Laura; Suquia, Angela G; Gines, Jordi; Rubio, Francisco; Ramos, Rafael; Besalduch, Joan

    2014-01-01

    The xCELLigence system is a new technological approach that allows the real-time cell analysis of adherent tumor cells. To date, xCELLigence has not been able to monitor the growth or cytotoxicity of nonadherent cells derived from hematological malignancies. The basis of its technology relies on the use of culture plates with gold microelectrodes located in their base. We have adapted the methodology described by others to xCELLigence, based on the pre-coating of the cell culture surface with specific substrates, some of which are known to facilitate cell adhesion in the extracellular matrix. Pre-coating of the culture plates with fibronectin, compared to laminin, collagen, or gelatin, significantly induced the adhesion of most of the leukemia/lymphoma cells assayed (Jurkat, L1236, KMH2, and K562). With a fibronectin substrate, nonadherent cells deposited in a monolayer configuration, and consequently, the cell growth and viability were robustly monitored. We further demonstrate the feasibility of xCELLigence for the real-time monitoring of the cytotoxic properties of several antineoplastic agents. In order to validate this technology, the data obtained through real-time cell analysis was compared with that obtained from using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide method. This provides an excellent label-free tool for the screening of drug efficacy in nonadherent cells and discriminates optimal time points for further molecular analysis of cellular events associated with treatments, reducing both time and costs. PMID:24959085

  5. Simulation of signal-to-noise ratio for the laser range-gated imaging system

    NASA Astrophysics Data System (ADS)

    Liang, Weiwei; Chen, Qianrong; Hao, Yongwang; Guo, Hao; Zhang, Wenpan

    2015-10-01

    The laser active imaging system is widely used in night vision, underwater imaging, three-dimension scene imaging and other civilian applications, and the system's detected range increase greatly comparing with the passive imaging system. In recent years, with rapid development of sensor and laser source technique, the laser range-gated imaging system is achieved based on high peak power pulsed laser and gated intensified CCD(ICCD), and it is well known for its properties such as high suppression of backscatter noise from fog and other obscurants, high resolution, long detection range and direct visualization. However, the performance of the laser range-gated imaging system is seriously affected by many factors, and the relationships between system's Signal-to-Noise Ratio (SNR) and influence factors are not further elaborated. In this paper, the simulation of SNR for the laser range-gated imaging system is studied. The principle of the laser range-gated imaging system is shown firstly, and the range equation is derived by means of deducing laser illuminating model according to the principle of laser radar and the characters of objects and the detectors. And then, the sources of noise are analyzed by accurately modeling all noise sources in the detection system, the model of SNR for laser range-gated imaging system is established. Finally, the relationships between SNR of system and influence factors such as gating time, laser pulse width and repetition frequency are discussed, and correspondingly the solutions are proposed.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. Discussion on operating range of shipborne infrared search-and-track system

    NASA Astrophysics Data System (ADS)

    Wei, Gang; Yang, Kun-tao

    2006-02-01

    The status and effect of the optronic system in shipborne weaponry have been widely accepted, for which each developed country takes it as essential equipement in equipment developing programme. Following radar, shipborne optronic system is another important means of detection from single set to multi-set network system step by step. For reasons that shipborne IRST system can overcome four threats of radar and is an extremely effective short-range defense and countermeasure equipment for threat targets flying in low altitude and superlow altitude, so every navy has attached great importance to it. After transforming the operating range equation of an IRST system, the integrated efficiency coefficient Q is derived, by which factors of influencing the operating range of an IRST system and the approaches to improving the operating range and its feasibility are analyzed in the paper. In the present stage, because of limitations of D* the area of pixels and of an infrared detector, the major method for improving the operating range is to increase the aperture with the transmittance of an optical system remaining unchanged basically. However, increasing the aperture, remaining F number constant, increasing the focal length, reducing the effective FOV will decrease the spacial detective efficiency. So the integrated efficiency of an IRST system can be improved by optimizing the range, detective efficiency and so forth reasonably under existing conditions.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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

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

    PubMed

    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

    2016-05-11

    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

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

    PubMed

    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

    2016-05-11

    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.

  18. The Charrette and Long-Range Planning in the Virginia Community College System. An Essay.

    ERIC Educational Resources Information Center

    Puyear, Donald E.

    1991-01-01

    Offers insights on the use of the charrette for long-range planning, drawing from the experience of the Virginia Community College System (VCCS). Defines charrettes, explains their benefits and limitations, lists requirements for successful charrettes, and explains the process used by the VCCS to incorporate the charrette into long-range planning.…

  19. Long range local effective potential for a three-particle system

    SciTech Connect

    Delfino, A.; Frederico, T.; Tomio, L.

    1988-07-01

    We derive the long- range behavior of an effective interaction for a system with three identical particles. We start our derivation from the zero range theory in configuration space and we show that the asymptotic effective potential, in the relative distance of the subsystem to the third particle, goes as -exp(-lambdar)/(r/sup 3/2/).

  20. 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...

  1. Dynamic range considerations when designing PC sound card based audiometric systems to test human hearing.

    PubMed

    Ellingson, Roger M; Dille, Marilyn L

    2010-01-01

    An investigation into maximizing the dynamic range of a PC sound card based audiometric test system is presented. Two principle sound paths are characterized: a) the analog line input, and, b) internal waveform conversion from digital formats into analog signals. Each signal path's electrical performance and overall dynamic range is measured using audio harmonic distortion analysis and frequency spectrum analysis tools. Recommendations are made for proper combinations of signal amplitude and mixer attenuation settings to maximize overall system dynamic range. This work could be useful for scientists using PC sound card based systems for psycho-acoustic testing purposes or for those using similar systems attempting to test the full range of human hearing. PMID:21096936

  2. Dynamic range considerations when designing PC sound card based audiometric systems to test human hearing.

    PubMed

    Ellingson, Roger M; Dille, Marilyn L

    2010-01-01

    An investigation into maximizing the dynamic range of a PC sound card based audiometric test system is presented. Two principle sound paths are characterized: a) the analog line input, and, b) internal waveform conversion from digital formats into analog signals. Each signal path's electrical performance and overall dynamic range is measured using audio harmonic distortion analysis and frequency spectrum analysis tools. Recommendations are made for proper combinations of signal amplitude and mixer attenuation settings to maximize overall system dynamic range. This work could be useful for scientists using PC sound card based systems for psycho-acoustic testing purposes or for those using similar systems attempting to test the full range of human hearing.

  3. Design and Development of High-Repetition-Rate Satellite Laser Ranging System

    NASA Astrophysics Data System (ADS)

    Choi, Eun-Jung; Bang, Seong-Cheol; Sung, Ki-Pyoung; Lim, Hyung-Chul; Jung, Chan-Gyu; Kim, In-Yeung; Choi, Jae-Seung

    2015-09-01

    The Accurate Ranging System for Geodetic Observation ? Mobile (ARGO-M) was successfully developed as the first Korean mobile Satellite Laser Ranging (SLR) system in 2012, and has joined in the International Laser Ranging Service (ILRS) tracking network, DAEdeoK (DAEK) station. The DAEK SLR station was approved as a validated station in April 2014, through the ILRS station ¡°data validation¡± process. The ARGO-M system is designed to enable 2 kHz laser ranging with millimeter-level precision for geodetic, remote sensing, navigation, and experimental satellites equipped with Laser Retroreflector Arrays (LRAs). In this paper, we present the design and development of a next generation high-repetition-rate SLR system for ARGO-M. The laser ranging rate up to 10 kHz is becoming an important issue in the SLR community to improve ranging precision. To implement high-repetition-rate SLR system, the High-repetition-rate SLR operation system (HSLR-10) was designed and developed using ARGO-M Range Gate Generator (A-RGG), so as to enable laser ranging from 50 Hz to 10 kHz. HSLR-10 includes both hardware controlling software and data post-processing software. This paper shows the design and development of key technologies of high-repetition-rate SLR system. The developed system was tested successfully at DAEK station and then moved to Sejong station, a new Korean SLR station, on July 1, 2015. HSLR-10 will begin normal operations at Sejong station in the near future.

  4. Non-mean-field effects in systems with long-range forces in competition.

    PubMed

    Bachelard, R; Staniscia, F

    2012-11-01

    We investigate the canonical equilibrium of systems with long-range forces in competition. These forces create a modulation in the interaction potential and modulated phases appear at the system scale. The structure of these phases differentiate this system from monotonic potentials, where only the mean-field and disordered phases exist. With increasing temperature, the system switches from one ordered phase to another through a first-order phase transition. Both mean-field and modulated phases may be stable, even at zero temperature, and the long-range nature of the interaction will lead to metastability characterized by extremely long time scales.

  5. Problem of the radiovision system resolution improvement in millimeter-wave range

    NASA Astrophysics Data System (ADS)

    Pirogov, Yuri A.; Attia, Magdy F.; Blankson, Isaiah M.; Dubina, Andrey I.; Gladun, Valeri V.; Papanicolopoulos, C. D.; Terentiev, Evgeni N.; Tarasova, Oksana A.

    1999-07-01

    At the Faculty of Physics of Moscow State University experimental researches of the working radiovision systems on the base of phased antenna array and radio optical systems with the sensors rules are carried out. Since 1980 the system of Sun radio observation in 3-mm wavelength range created by the specialists of Bauman Moscow State Technical University is exploited. Investigations in the mathematical modeling of image formation systems in wide wavelength range with different receiving schemes and with distortion compensation task solution and super-resolution are conducted by mathematician and physicists.

  6. 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.

  7. 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.

  8. 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.

  9. Radio science requirements and the end-to-end ranging system

    NASA Technical Reports Server (NTRS)

    Berman, A. L.

    1978-01-01

    Radio science ranging requirements negotiated between past and present flight projects and the DSN have generally focused on just the DSS and spacecraft hardware. All elements in the end-to-end system are analyzed and considered in terms of the error hierarchy. The end-to-end system is defined and examined as it applies to the generation of radio science ranging requirements. The variability of the performance levels of the system elements is emphasized with respect to the radio science experiment being performed and the DSN-spacecraft frequency band configuration.

  10. 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.

  11. 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.

  12. Direct optimization of LWIR systems for maximized detection range and minimized size and weight

    NASA Astrophysics Data System (ADS)

    Bates, Rob; Kubala, Kenneth

    2014-05-01

    With reductions in microbolometer size and cost, long-wave infrared (LWIR) systems are increasingly being developed for platforms with challenging size, weight, power, and cost (SWAP-C) constraints, such as helmet-mounted systems and unmanned vehicles. Past optimization of imaging systems toward the simultaneous objectives of improved stand-off detection and low size, weight, and power required an iterative, multi-disciplinary design process. Here we demonstrate the direct optimization of the full LWIR system model including the optics, sensor, signal processing, and display degrees of freedom with system level metrics including SWAP-C and detection range. The end result is a system with superior size and weight for a given detection range.

  13. 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.

  14. 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.

  15. 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.

  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

    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. PMID:23393961

  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

    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. PMID:23837350

  18. High-bandwidth, high-dynamic-range, analog optical guided-wave systems for physics instrumentation

    NASA Astrophysics Data System (ADS)

    Lowry, M.; Haigh, R.; Hugenberg, K.; Masquelier, D.; McConaghy, C.; McCammon, K.; Nelson, D.; Roeske, F.

    1992-07-01

    Two remote measurement systems that efficiently exploit the information transmission capacity of optical guided-wave technology are developed. The first system, which operates at 820 nm, was developed for nuclear weapons measurements and emphasizes high-bandwidth high-dynamic range information transmission. The second system was developed for the detector readout at the Super-Conducting Super Collider (SSC); this system emphasizes high charge sensitivity measurement transmission and operates at 1320 nm. Most of the component design (including modeling), fabrication, packaging, characterization, and system integration was done at Lawrence Livermore National Laboratory (LLNL) specifically for these specialized physics measurements applications.

  19. High-bandwidth, high-dynamic-range, analog optical guided-wave systems for physics instrumentation

    SciTech Connect

    Lowry, M.; Haigh, R.; Hugenberg, K.; Masquelier, D.; McConaghy, C.; McCammon, K.; Nelson, D.; Roeske, F.

    1992-07-01

    We have developed two remote measurement systems that efficiently exploit the information transmission capacity of optical guided-wave technology. The first system, which operates at 820 nm, was developed for nuclear weapons measurements and emphasizes high-bandwidth high-dynamic range information transmission. The second system was developed for the detector readout at the Super-Conducting Super Collider (SSC); this system emphasizes high charge sensitivity measurement transmission and operates at 1320 nm. Most of the component design (including modeling), fabrication, packaging, characterization, and system integration was done at LLNL specifically for these specialized physics measurements applications.

  20. Laser speckle reduction by phase range limited computer generated hologram in laser projection display system.

    PubMed

    Chang, Yan-Shuo; Lin, Chia-Hsin; Hsu, Ku-Hui; Hsu, Wei-Feng; Hsiao, Li-Jen; Lin, Hoang Yan

    2014-09-20

    The speckle phenomenon is an annoyance in laser projection display systems. We propose a novel speckle suppression method that utilizes the interference concept on a pixel point, which reduces the speckle contrast (SC) of the project image by limiting the phase distribution range in the optical field. The SC formula is derived in the uniform interval phase range for partially developed speckle conditions, showing that the SC can be lowered by lessening the phase range limitation. In the ideal simulation model, the SC can be reduced from 98.77% to 0% as the phase range limitation varies from 2π to 0. The phase range limitation model is a novel method using a computer generated hologram to provide beam shaping and phase limitation. In a more realistic simulation model, the SC is reduced from 99.18% to 16.68%.

  1. Viability of the Vulnerability Thesis.

    ERIC Educational Resources Information Center

    Lutz, Frank W.

    1996-01-01

    Summarizes the viability of the vulnerability thesis as a tool in accounting for school superintendent behavior today, suggesting how the thesis can be built on in order to better understand the political world of superintendency. The paper suggests some social and political theories that might extend the thesis, further clarifying the…

  2. Effect of the short-range interaction on critical phenomena in elastic interaction systems

    NASA Astrophysics Data System (ADS)

    Nishino, Masamichi; Miyashita, Seiji

    2013-07-01

    The elastic interaction, induced by the lattice distortion due to the difference of the molecular size, causes an effective long-range interaction. In spin-crossover (SC) compounds, local bistable states, i.e., high-spin and low-spin states, have different molecular sizes, and the elastic interaction is important. In bipartite lattices, e.g., the square lattice, the ground state can be two types of phases: ferromagneticlike and antiferromagneticlike phases. In systems like SC compounds, the former phase consists of all small or large molecules, and the latter phase has the configuration of alternating small and large molecules. In fact, both cases are observed in SC systems. In this paper we have studied the effect of the short-range interaction in the elastic system on the properties of those order-disorder phase transitions. We have obtained a phase diagram in the coordinates of the temperature and the strength of the short-range interaction, including the metastable structures. We show that effects of the short-range interaction are essentially different for ferromagneticlike and antiferromagneticlike phase transitions. In the ferromagneticlike transition, the long-range interaction of elasticity is relevant, and the system exhibits a phase transition in the mean-filed universality class. In this case, the long-range interaction strongly enhances the ferromagneticlike order, and it works cooperatively with the short-range interaction. In contrast, in the antiferromagneticlike transition, the elastic interaction slightly enhances the antiferromagneticlike order, but essentially it does not contribute to the ordering, and the system shows a transition in the Ising universality class. We have found that in the border region between ferromagneticlike and antiferromagneticlike phases, the antiferromagneticlike phase has an advantage at finite temperatures. We discuss the critical properties of two-step SC transitions with comparison between the elastic interaction

  3. 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.

  4. 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.

  5. An emittance measurement system for a wide range of bunch charges

    SciTech Connect

    Dunham, B.; Engwall, D.; Hofler, A.; Keesee, M.; Legg, R.

    1997-06-01

    As a part of the emittance measurements planned for the FEL injector at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), the authors have developed an emittance measurement system that covers the wide dynamic range of bunch charges necessary to fully characterize the high-DC-voltage photocathode gun. The measurements are carried out with a variant of the classical two-slit method using a slit to sample the beam in conjunction with a wire scanner to measure the transmitted beam profile. The use of commercial, ultra-low noise picoammeters makes it possible to cover the wide range of desired bunch charges, with the actual measurements made over the range of 0.25 pC to 125 pC. The entire system, including its integration into the EPICS control system, is discussed.

  6. 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.

  7. 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. PMID:26759708

  8. 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

  9. 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.

  10. 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.

  11. Development of Acceleration Sensor and Acceleration Evaluation System for Super-Low-Range Frequencies

    NASA Astrophysics Data System (ADS)

    Asano, Shogo; Matsumoto, Hideki

    2001-05-01

    This paper describes the development process for acceleration sensors used on automobiles and an acceleration evaluation system designed specifically for acceleration at super-low-range frequencies. The features of the newly developed sensor are as follows. 1) Original piezo-bimorph design based on a disc-center-fixed structure achieves pyroeffect cancelling and stabilization of sensor characteristics and enables the detection of the acceleration of 0.0009 G at the super-low-range-frequency of 0.03 Hz. 2) The addition of a self-diagnostic function utilizing the characteristics of piezoceramics enables constant monitoring of sensor failure. The frequency range of acceleration for accurate vehicle motion control is considered to be from DC to about 50 Hz. However, the measurement of acceleration in the super-low-range frequency near DC has been difficult because of mechanical and electrical noise interruption. This has delayed the development of the acceleration sensor for automotive use. We have succeeded in the development of an acceleration evaluation system for super-low-range frequencies from 0.015 Hz to 2 Hz with detection of the acceleration range from 0.0002 G (0.2 gal) to 1 G, as well as the development of a piezoelectric-type acceleration sensor for automotive use.

  12. 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.

  13. 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.

  14. 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.

  15. Universalities for the Efimov-favored system with finite-range interactions

    NASA Astrophysics Data System (ADS)

    Wu, Meng-Shan; Han, Hui-Li; Shi, Ting-Yun

    2016-06-01

    Universal properties of Efimov states for some triatomic systems composed by one light and two heavy atoms are investigated using the finite-range model potentials. We have successfully obtained accurate values of binding energies and sizes for three successive Efimov states. Compared with the predicted scaling constants of the zero-range theory, the ground Efimov states are found to have the largest finite-range corrections. There exists a universal size-binding momentum relation for Efimov states which can be described by the formula Rn*kn*=√{(1 +s02)/3 } derived with zero-range approximation. It is found that for the Efimov states that have large scaled sizes, their size-binding momentum relations follow the universal formula well. Our calculations demonstrate that size is an important characteristic in determining the universalities of Efimov states.

  16. Selection Criterion of Gauges for Vacuum Measurements of Systems with Diverse Ranges

    NASA Astrophysics Data System (ADS)

    Akram, H. M.; Fasih, A.

    Basically a vacuum gauge is a key that opens the secrets of a closed vacuum system, indicates what is happening inside the sealed makeup and has the facility to control it through evacuation system. But for the broad vacuum range, all the goings-on are not made known or commanded by a particular vacuum gauge. Consequently, various gauges of special types are used to accurately measure the vacuum of diverse ranges, together with the requisite services. Therefore, the selection of proper gauge in favor of exact vacuum metrology in conjunction with extra actions, for a particular vacuum work, is of primary importance. There are many factors that affect the appropriate gauge selection. In this paper, selection criterion for suitable vacuum gauge, supportive for accurate vacuum measurements and other critical functions of the required range, has briefly been discussed that can make the task of gauge selection simpler and exact.

  17. 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.

  18. 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

  19. Robust range estimation with a monocular camera for vision-based forward collision warning system.

    PubMed

    Park, Ki-Yeong; Hwang, Sun-Young

    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.

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. Development of proton CT imaging system for evaluation of proton range calculation accuracy

    NASA Astrophysics Data System (ADS)

    Tanaka, Sodai; Nishio, Teiji; Matsushita, Keiichiro; Tsuneda, Masato; Aono, Yuki; Kabuki, Shigeto; Sugiura, Akinori; Uesaka, Mitsuru

    2014-09-01

    [Purpose] In treatment planning of proton therapy, X-ray CT image is generally utilized for proton dose and range calculations in a patient body. However, there is an error of the conversion from CT value to WEL (Water Equivalent Length), and it turns into the error of proton range calculation. Therefore, WEL can be directly derived by use of pixel value on proton CT (pCT) image. The purpose of this study is development of a simple and convenient pCT imaging system for evaluation of proton range calculation accuracy. [Method] PCT imaging system was constructed with a plastic scintillator and a cooled CCD camera, which acquires the image of integrated value of the scintillation light toward the beam direction. Experiment for evaluation of this system with 70-MeV protons provided by NIRS cyclotron was performed. The proton beam was irradiated to objects of water and other substances phantom with complicated shape. The pCT image reconstructed from the experimental data was quantitatively evaluated. [Result] Construction of pCT image of various objects was successful. The value of WEL factor of water was 1.0 +/-0.1. [Conclusion] The simple and convenient pCT imaging system for evaluation of proton range calculation accuracy was developed and was evaluated by experiment using proton beam.

  5. 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.

  6. 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.

  7. 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.

  8. Viability of bacteria in peatlands

    NASA Astrophysics Data System (ADS)

    Bogdanova, O. Yu.; Golovchenko, A. V.; Lysak, L. V.; Glukhova, T. V.; Zvyagintsev, D. G.

    2014-04-01

    The viability of bacteria in oligotrofic bogs and fens was determined by the luminescent microscopy method with the help of a two-component fluorescent dye (L7012 LIVE/DEAD). Living bacterial cells were found in the entire peat profiles. Their portion was maximal (up to 60%) in the upper layers and did not exceed 25% in the lower layers. The portion of dead bacterial cells varied from 3 to 19%, and dormant cells constituted 25 to 95% of the total number of bacterial cells. The numbers of dormant cells increased down the profiles irrespectively of the peat type. The portion of nanoforms did not exceed 5% of the total. The cells of the nanoforms, unlike the bacteria of typical sizes, were characterized by their high viability (93-98%).

  9. 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.

  10. 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.

  11. Model-based restoration using light vein for range-gated imaging systems.

    PubMed

    Wang, Canjin; Sun, Tao; Wang, Tingfeng; Wang, Rui; Guo, Jin; Tian, Yuzhen

    2016-09-10

    The images captured by an airborne range-gated imaging system are degraded by many factors, such as light scattering, noise, defocus of the optical system, atmospheric disturbances, platform vibrations, and so on. The characteristics of low illumination, few details, and high noise make the state-of-the-art restoration method fail. In this paper, we present a restoration method especially for range-gated imaging systems. The degradation process is divided into two parts: the static part and the dynamic part. For the static part, we establish the physical model of the imaging system according to the laser transmission theory, and estimate the static point spread function (PSF). For the dynamic part, a so-called light vein feature extraction method is presented to estimate the fuzzy parameter of the atmospheric disturbance and platform movement, which make contributions to the dynamic PSF. Finally, combined with the static and dynamic PSF, an iterative updating framework is used to restore the image. Compared with the state-of-the-art methods, the proposed method can effectively suppress ringing artifacts and achieve better performance in a range-gated imaging system. PMID:27661357

  12. Self-Induced Glassiness and Pattern Formation in Spin Systems Subject to Long-Range Interactions

    NASA Astrophysics Data System (ADS)

    Principi, Alessandro; Katsnelson, Mikhail I.

    2016-09-01

    We study the glass formation in two- and three-dimensional Ising and Heisenberg spin systems subject to competing interactions and uniaxial anisotropy with a mean-field approach. In three dimensions, for sufficiently strong anisotropy the systems always modulate in a striped phase. Below a critical strength of the anisotropy, a glassy phase exists in a finite range of temperature, and it becomes more stable as the system becomes more isotropic. In two dimensions the criticality is always avoided and the glassy phase always exists.

  13. 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.

  14. Advanced technologies in the ASI MLRO towards a new generation laser ranging system

    NASA Astrophysics Data System (ADS)

    Varghese, Thomas; Bianco, Giuseppe

    1994-11-01

    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.

  15. 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.

  16. 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. PMID:27391705

  17. 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.

  18. 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.

  19. 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.

  20. Further results on delay-range-dependent stability with additive time-varying delay systems.

    PubMed

    Liu, Pin-Lin

    2014-03-01

    In this paper, new conditions for the delay-range-dependent stability analysis of time-varying delay systems are proposed in a Lyapunov-Krasovskii framework. Time delay is considered to be time-varying and has lower and upper bounds. A new method is first presented for a system with two time delays, integral inequality approach (IIA) used to express relationships among terms of Leibniz-Newton formula. Constructing a novel Lyapunov-Krasovskii functional includes information belonging to a given range; new delay-range-dependent criterion is established in term of linear matrix inequality (LMI). The advantage of that criterion lies in its simplicity and less conservative. This paper also presents a new result of stability analysis for continuous systems with two additive time-variant components representing a general class of delay with strong application background in network-based control systems. Resulting criteria are then expressed in terms of convex optimization with LMI constraints, allowing for use of efficient solvers. Finally, three numerical examples show these methods reducing conservatism and improving maximal allowable delay.

  1. Radiometric calibration method for large aperture infrared system with broad dynamic range.

    PubMed

    Sun, Zhiyuan; Chang, Songtao; Zhu, Wei

    2015-05-20

    Infrared radiometric measurements can acquire important data for missile defense systems. When observation is carried out by ground-based infrared systems, a missile is characterized by long distance, small size, and large variation of radiance. Therefore, the infrared systems should be manufactured with a larger aperture to enhance detection ability and calibrated at a broader dynamic range to extend measurable radiance. Nevertheless, the frequently used calibration methods demand an extended-area blackbody with broad dynamic range or a huge collimator for filling the system's field stop, which would greatly increase manufacturing costs and difficulties. To overcome this restriction, a calibration method based on amendment of inner and outer calibration is proposed. First, the principles and procedures of this method are introduced. Then, a shifting strategy of infrared systems for measuring targets with large fluctuations of infrared radiance is put forward. Finally, several experiments are performed on a shortwave infrared system with Φ400  mm aperture. The results indicate that the proposed method cannot only ensure accuracy of calibration but have the advantage of low cost, low power, and high motility. Hence, it is an effective radiometric calibration method in the outfield.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. High density, multi-range analog output Versa Module Europa board for control system applications

    NASA Astrophysics Data System (ADS)

    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.

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. Long range planning for the development of space flight emergency systems.

    NASA Technical Reports Server (NTRS)

    Bolger, P. H.; Childs, C. W.

    1972-01-01

    The importance of long-range planning for space flight emergency systems is pointed out. Factors in emergency systems planning are considered, giving attention to some of the mission classes which have to be taken into account. Examples of the hazards in space flight include fire, decompression, mechanical structure failures, radiation, collision, and meteoroid penetration. The criteria for rescue vehicles are examined together with aspects regarding the conduction of rescue missions. Future space flight programs are discussed, taking into consideration low earth orbit space stations, geosynchronous orbit space stations, lunar operations, manned planetary missions, future space flight vehicles, the space shuttle, special purpose space vehicles, and a reusable nuclear shuttle.

  18. Extending the viability of acute brain slices

    PubMed Central

    Buskila, Yossi; Breen, Paul P.; Tapson, Jonathan; van Schaik, André; Barton, Matthew; Morley, John W.

    2014-01-01

    The lifespan of an acute brain slice is approximately 6–12 hours, limiting potential experimentation time. We have designed a new recovery incubation system capable of extending their lifespan to more than 36 hours. This system controls the temperature of the incubated artificial cerebral spinal fluid (aCSF) while continuously passing the fluid through a UVC filtration system and simultaneously monitoring temperature and pH. The combination of controlled temperature and UVC filtering maintains bacteria levels in the lag phase and leads to the dramatic extension of the brain slice lifespan. Brain slice viability was validated through electrophysiological recordings as well as live/dead cell assays. This system benefits researchers by monitoring incubation conditions and standardizing this artificial environment. It further provides viable tissue for two experimental days, reducing the time spent preparing brain slices and the number of animals required for research. PMID:24930889

  19. 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.

  20. 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.

  1. 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. PMID:24229143

  2. 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.

  3. 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.

  4. Food safety in free-range and organic livestock systems: risk management and responsibility.

    PubMed

    Kijlstra, A; Meerburg, B G; Bos, A P

    2009-12-01

    Animal production systems that offer outdoor access to the animals have become increasingly popular in the Western world due to the growing general discontent of consumers with conventional bioindustrial farming practices. These open production systems offer improved animal welfare but may create new problems for animal health, resulting in increased food safety risks from bacterial, viral, or parasitic infections or environmental contaminants. Examples of these new problems include increased Toxoplasma gondii infections in pigs and high dioxin levels in eggs from free-range hens. In this review, the relation between positive and negative points of free-range and organic livestock production systems is discussed with reference to production in The Netherlands. We investigated how proponents of more animal welfare friendly systems deal with potential negative issues in public and whether any risk communication is used. Generally, we found that the existence of a dilemma is disputed or avoided in communication with the consumer. This avoidance could be detrimental for public trust in alternative animal production systems, should problems occur. To prevent future problems, it will be necessary to communicate about the relevant types and sources of the food safety risks to the consumers. The responsibility for protecting food safety should be properly divided among the various parties involved: producers, processors, governments, nongovernmental organizations, and consumers.

  5. Food safety in free-range and organic livestock systems: risk management and responsibility.

    PubMed

    Kijlstra, A; Meerburg, B G; Bos, A P

    2009-12-01

    Animal production systems that offer outdoor access to the animals have become increasingly popular in the Western world due to the growing general discontent of consumers with conventional bioindustrial farming practices. These open production systems offer improved animal welfare but may create new problems for animal health, resulting in increased food safety risks from bacterial, viral, or parasitic infections or environmental contaminants. Examples of these new problems include increased Toxoplasma gondii infections in pigs and high dioxin levels in eggs from free-range hens. In this review, the relation between positive and negative points of free-range and organic livestock production systems is discussed with reference to production in The Netherlands. We investigated how proponents of more animal welfare friendly systems deal with potential negative issues in public and whether any risk communication is used. Generally, we found that the existence of a dilemma is disputed or avoided in communication with the consumer. This avoidance could be detrimental for public trust in alternative animal production systems, should problems occur. To prevent future problems, it will be necessary to communicate about the relevant types and sources of the food safety risks to the consumers. The responsibility for protecting food safety should be properly divided among the various parties involved: producers, processors, governments, nongovernmental organizations, and consumers. PMID:20003752

  6. 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.

  7. Rapid determination of yeast viability

    SciTech Connect

    Lee, S.S.; Robinson, F.M.; Wang, H.Y.

    1981-01-01

    A modified simple staining method using Methylene blue to distinguish between live and dead cells has been developed. Methylene blue (0.025%, w/v) in full strength Ringer solution with 1% glucose (w/v) added is used as the standard staining solution. Satisfactory and reproducible results can be obtained through microscopic examination using this staining method. The ratio of viable cells to nonviable cells is constant for at least two days if the proper environmental conditions are provided. This method was used to demonstrate the effects of various factors that influence yeast viability.

  8. 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

  9. System gamma as a function of image- and monitor-dynamic range.

    PubMed

    Kane, David; Bertalmío, Marcelo

    2016-01-01

    System gamma is the end-to-end exponent that describes the relationship between the relative luminance values at capture and the reproduced image. The system gamma preferred by subjects is known to vary with the background luminance condition and the image in question. We confirm the previous two findings using an image database with both high and low dynamic range images (from 102 to 107), but also find that the preferred system gamma varies with the dynamic range of the monitor (CRT, LCD, or OLED). We find that the preferred system gamma can be predicted in all conditions and for all images by a simple model that searches for the value that best flattens the lightness distribution, where lightness is modeled as a power law of onscreen luminance. To account for the data, the exponent must vary with the viewing conditions. The method presented allows the inference of lightness perception in natural scenes without direct measurement and makes testable predictions for how lightness perception varies with the viewing condition and the distribution of luminance values in a scene. The data from this paper has been made available online. PMID:27271806

  10. 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.

  11. 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.

  12. Emergent Ultra-Long-Range Interactions Between Active Particles in Hybrid Active-Inactive Systems

    NASA Astrophysics Data System (ADS)

    Steimel, Joshua; Aragones, Juan; Hu, Helen; Qureshi, Naser; Alexander-Katz, Alfredo

    Particle-particle interactions determine the state of a system. Control over the range and magnitude of such interactions has been an active area of research for decades due to the fundamental challenges it poses in science and technology. 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, immobile objects and structures, here we study the effective interactions that appear in systems composed of active and passive mixtures of colloids. Our system is a two dimensional colloidal monolayer composed primarily of passive (inactive) colloids and a very small fraction of active (sinning) ferromagnetic colloids. We find an emergent ultra-long-range attractive interaction between active particles 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 time scale 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.

  13. Emergent ultra-long-range interactions between active particles in hybrid active-inactive systems.

    PubMed

    Steimel, Joshua P; Aragones, Juan L; Hu, Helen; Qureshi, Naser; Alexander-Katz, Alfredo

    2016-04-26

    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.

  14. 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

  15. 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. PMID:27288936

  16. Long-range interacting many-body systems with alkaline-earth-metal atoms.

    PubMed

    Olmos, B; Yu, D; Singh, Y; Schreck, F; Bongs, K; Lesanovsky, I

    2013-04-01

    Alkaline-earth-metal atoms can exhibit long-range dipolar interactions, which are generated via the coherent exchange of photons on the (3)P(0) - (3)D(1) transition of the triplet manifold. In the case of bosonic strontium, which we discuss here, this transition has a wavelength of 2.6 μm and a dipole moment of 4.03 D, and there exists a magic wavelength permitting the creation of optical lattices that are identical for the states (3)P(0) and (3)D(1). This interaction enables the realization and study of mixtures of hard-core lattice bosons featuring long-range hopping, with tunable disorder and anisotropy. We derive the many-body master equation, investigate the dynamics of excitation transport, and analyze spectroscopic signatures stemming from coherent long-range interactions and collective dissipation. Our results show that lattice gases of alkaline-earth-metal atoms permit the creation of long-lived collective atomic states and constitute a simple and versatile platform for the exploration of many-body systems with long-range interactions. As such, they represent an alternative to current related efforts employing Rydberg gases, atoms with large magnetic moment, or polar molecules.

  17. A new synchronization control circuit based on FPGA for the laser range-gated imaging system

    NASA Astrophysics Data System (ADS)

    He, Shan; Li, Li; Zhou, Yan

    2009-07-01

    Synchronization control is a kernel technique of the laser range-gated (LRG) imaging system which controls the synchronization of the pulsed laser and the ICCD camera directly. It can achieve range gating effectively and improve the resolution of image precisely. Conventional control circuits which are composed of discrete components have a poor performance of anti-interference, and the transmitting signal has a bad delay which affects the conventional circuit’s precision and stabilization seriously. To solve these problems, a range-gated synchronization control circuit is designed. This circuit, which takes the advantages of FPGA’s high compact and flexibility, uses the phase-locking-loop (PLL) to multiply the global clock frequency. This design improves the precision and stabilization greatly, makes the precision up to a nanosecond level and provides a real-time selection of the values of pulse width and delays. Experiments results indicate that this circuit has a high precise and stable range-gated pulse.

  18. 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.

  19. 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.

  20. 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

    2010-11-01

    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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. Developing a Predictive Metric to Assess School Viability

    ERIC Educational Resources Information Center

    James, John T.; Tichy, Karen L.; Collins, Alan; Schwob, John

    2008-01-01

    This article examines a wide range of parish school indicators that can be used to predict long-term viability. The study reported in this article explored the relationship between demographic variables, financial variables, and parish grade school closures in the Archdiocese of Saint Louis. Specifically, this study investigated whether…

  7. Short and Medium Range Hydrometeorological Ensemble Prediction System: A mesoscale case study in Denmark

    NASA Astrophysics Data System (ADS)

    Lucatero, D.; Madsen, H.; Refsgaard, J.; Kidmose, J.; Jensen, K.; Feddersen, H.; Sass, B.

    2013-12-01

    Recent floods in Europe have increased the need to improve flood prediction systems that will allow, firstly, for proper analysis of the uncertainties in the hydrological predictions and, secondly, for the generation of probabilistic forecasts. The use of Meteorological Ensemble Prediction Systems (MEPS) to propagate climate input uncertainty throughout the hydrological modeling process is a state-of-the-art methodology for issuing probabilistic forecasts. MEPS have been made operational at meteorological centers around the globe for both short and medium range forecasting. The European Centre for Medium-Range Weather Forecasts (ECMWF) issues probabilistic forecasts with a resolution of approximately 25 kilometers using 50 ensemble members. The forecasts are issued twice per day with a lead time up to 15 days. Likewise, the Danish Meteorological Institute (DMI) issues probabilistic forecasts for a limited area covering Northern Europe with 25 ensemble members. DMI's MEPS has a spatial resolution of 5 kilometers, a lead time of 48 hours and is issued four times per day. Our research focuses on the implementation of both MEPS as input variables in a hydrological forecast model. We are aiming at generating seamless probabilistic forecasts of hydrological variables such as streamflow and groundwater levels for Silkeborg city in Denmark. A MIKE SHE coupled surface-groundwater hydrological model set up for the Silkeborg catchment is used for the hydrological forecast. Short and medium range forecasts for streamflows and groundwater levels of past events are analyzed in order to study the feasibility and skills of the flood forecasting system. Several measures of skill are described and analyzed in order to detect biases and lack of accuracy in our forecast system. A study of the reliability, skill over climatology/persistence forecasting, resolution, discrimination, etc., was made by means of the analysis of the joint distribution of the forecasts and observations of

  8. Global positioning system reoccupation of early triangulation sites - Tectonic deformation of the Southern Coast Ranges

    NASA Astrophysics Data System (ADS)

    Shen, Zheng-Kang; Jackson, David D.

    1993-06-01

    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.

  9. 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

  10. 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.

  11. Divergence of the entanglement range in low-dimensional quantum systems

    SciTech Connect

    Amico, L.; Patane, D.; Baroni, F.; Fubini, A.; Tognetti, V.; Verrucchi, Paola

    2006-08-15

    We study the pairwise entanglement close to separable ground states of a class of one-dimensional quantum spin models. At T=0 we find that such ground states separate regions, in the space of the Hamiltonian parameters, which are characterized by qualitatively different types of entanglement, namely parallel and antiparallel entanglement; we further demonstrate that the range of the concurrence diverges while approaching separable ground states, therefore evidencing that such states, with uncorrelated fluctuations, are reached by a long range reshuffling of the entanglement. We generalize our results to the analysis of quantum phase transitions occurring in bosonic and fermionic systems. Finally, the effects of finite temperature are considered: At T>0 we evidence the existence of a region where no pairwise entanglement survives, so that entanglement, if present, is genuinely multipartite.

  12. 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.

  13. 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.

  14. A numerical investigation on the efficiency of range extending systems using Advanced Vehicle Simulator

    NASA Astrophysics Data System (ADS)

    Varnhagen, Scott; Same, Adam; Remillard, Jesse; Park, Jae Wan

    2011-03-01

    Series plug-in hybrid electric vehicles of varying engine configuration and battery capacity are modeled using Advanced Vehicle Simulator (ADVISOR). The performance of these vehicles is analyzed on the bases of energy consumption and greenhouse gas emissions on the tank-to-wheel and well-to-wheel paths. Both city and highway driving conditions are considered during the simulation. When simulated on the well-to-wheel path, it is shown that the range extender with a Wankel rotary engine consumes less energy and emits fewer greenhouse gases compared to the other systems with reciprocating engines during many driving cycles. The rotary engine has a higher power-to-weight ratio and lower noise, vibration and harshness compared to conventional reciprocating engines, although performs less efficiently. The benefits of a Wankel engine make it an attractive option for use as a range extender in a plug-in hybrid electric vehicle.

  15. Precise control of coupling strength in photonic molecules over a wide range using nanoelectromechanical systems.

    PubMed

    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

  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. Note: A novel dielectric barrier discharge system for generating stable patterns in wide range

    NASA Astrophysics Data System (ADS)

    Liu, Weibo; Wang, Yongjie; Zhang, Hao; Pan, Yuyang; Dong, Lifang

    2016-05-01

    We develop a novel dielectric barrier discharge (DBD) system with a meshed water electrode to generate stable square superlattice patterns (MSSP) in Ar/air mixture in a wide range of experimental environments. Discharge scenarios with the applied voltage increasing in the meshed DBD and ordinary DBD are presented respectively under the same experimental conditions. It is found that a square pattern and MSSP can be obtained stably and easily in meshed DBD, while no pattern emerges in ordinary DBD. MSSP can be formed when the Ar content is from 0% to 70%, and the corresponding applied voltage decreases with Ar content increasing. Results based on optical methods show that MSSP is generated by artificially designed electrodes together with nonlinear characteristics of DBD, which may account for why patterns in meshed DBD exist in a wide range.

  18. 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.

  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...

  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...

  1. 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...

  2. 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...

  3. 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

  4. 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

  5. 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.

  6. Long-range force and moment calculations in multiresolution simulations of molecular systems

    SciTech Connect

    Poursina, Mohammad; Anderson, Kurt S.

    2012-08-30

    Multiresolution simulations of molecular systems such as DNAs, RNAs, and proteins are implemented using models with different resolutions ranging from a fully atomistic model to coarse-grained molecules, or even to continuum level system descriptions. For such simulations, pairwise force calculation is a serious bottleneck which can impose a prohibitive amount of computational load on the simulation if not performed wisely. Herein, we approximate the resultant force due to long-range particle-body and body-body interactions applicable to multiresolution simulations. Since the resultant force does not necessarily act through the center of mass of the body, it creates a moment about the mass center. Although this potentially important torque is neglected in many coarse-grained models which only use particle dynamics to formulate the dynamics of the system, it should be calculated and used when coarse-grained simulations are performed in a multibody scheme. Herein, the approximation for this moment due to far-field particle-body and body-body interactions is also provided.

  7. 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.

  8. Application of viability theory for road vehicle active safety during cornering manoeuvres

    NASA Astrophysics Data System (ADS)

    Vandanjon, P.-O.; Coiret, A.; Lorino, T.

    2014-02-01

    Viability theory proposes geometric metaphors in addition to classical ordinary differential equation analysis. In this paper, advantages of applying viability theory to road safety domain are presented. The exact issue is to determine if, from an initial state of a vehicle/road/driver system, a soft controls strategy is compatible with a safe driving sequence. The case of a car negotiating a curve is considered. The application of the viability theory to this issue offers the advantage to avoid classical full computing of the system. Instead of that, it consists on verifying that the states and the controls belong to a subset called the viability kernel. The construction and the use of the viability kernel for a vehicle system dynamic is proposed by using support vector machines algorithm. Then, the applicability of this theory is demonstrated through experimental tests. This innovative application of the viability theory to vehicle dynamics with road safety concerns could benefit to robust embedded warning systems.

  9. Research on long-range laser active imaging system applied in adverse weather conditions

    NASA Astrophysics Data System (ADS)

    Gai, Zhi-gang; Liu, Meng-de; Yang, Li; Kabanov, V. V.; Shi, Lei; Zhao, Jie; Chu, Shi-bo; Yang, Jun-xian; Zhou, Yang

    2013-09-01

    A low-light level night vision device or thermal infrared imager belonging to passive imaging system is generally used in daily target detection and identification. But in adverse weather conditions of dark of night, poor atmospheric transmission characteristics or strong backscattering (fog, dust, rain, snow, etc.), even the most sensitive low-light level night vision could not provide enough image resolution for detecting and identifying targets, and the thermal infrared imager is also limited by low temperature contrast. A long-range laser active imaging system, in combination with high-power semiconductor pulsed lasers with collimation technology, receiving objective lens of large diameter, long focal length and narrow viewing angle, high-gain image intensifier CCD (ICCD) camera and range-gated synchronization control technology, is developed for long distance target detection and high resolution imaging in adverse weather conditions. The system composition and operating principle are introduced. The extremely powerful and efficient illuminators with collimation technology are able to deliver uniform beams, which are essential for illuminating targets at a distance and generating high-quality images. The particular receiving objective lens, ICCD camera and range-gated synchronization control technology could reduce strong backscattering signal and improve imaging signal-to-noise ratio. The laboratory and outfield experiments have been done to validate imaging effect and imaging quality. The results show that the minimum resolution is about 3-5cm, 10cm, and greater than 20 cm for target far from 1100m, 4700m, and 6700m respectively in dark of night. Furthermore, the minimum resolution could reach to 10cm and 20cm for target far from 2500m and 4800m respectively and the image is too blurred to accurately identify the target when observing the target far from 7200m in rainy condition.

  10. 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.

  11. Controlling the long-range corrections in atomistic Monte Carlo simulations of two-phase systems.

    PubMed

    Goujon, Florent; Ghoufi, Aziz; Malfreyt, Patrice; Tildesley, Dominic J

    2015-10-13

    The long-range correction to the surface tension can amount to up to 55% of the calculated value of the surface tension for cutoffs in the range of 2.1-6.4 σ. The calculation of the long-range corrections to the surface tension and to the configurational energy in two-phase systems remains an active area of research. In this work, we compare the long-range corrections methods proposed by Guo and Lu ( J. Chem. Phys. 1997 , 106 , 3688 - 3695 ) and Janeček ( J. Phys. Chem. B 2006 , 110 , 6264 - 6269 ) for the calculation of the surface tension and of the coexisting densities in Monte Carlo simulations of the truncated Lennard-Jones potential and the truncated and shifted Lennard-Jones potential models. These methods require an estimate of the long-range correction at each step in the Monte Carlo simulation. We apply the full version of the Guo and Lu method, which involves the calculation of a double integral that contains a series of density differences, and we compare these results with the simplified version of the method which is routinely used in two-phase simulations. We conclude that the cutoff dependencies of the surface tension and coexisting densities are identical for the full versions of Guo and Lu and Janeček methods. We show that it is possible to avoid applying the long-range correction at every step by using the truncated Lennard-Jones potential with a cutoff rc ≥ 5 σ. The long-range correction can then be applied at the end of the simulation. The limiting factor in the accurate calculation of this final correction is an accurate estimate of the coexisting densities. Link-cell simulations performed using a cutoff rc = 5.5 σ require twice as much computing time as those with a more typical cutoff of rc = 3.0 σ. The application of the Janeček correction increases the running time of the simulation by less than 10%, and it can be profitably applied with the shorter cutoff. PMID:26574249

  12. 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.

  13. 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.

  14. 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.

  15. New Features of Rescaled Range Analysis of the Running Sandpile With Applications to Geophysical Systems

    NASA Astrophysics Data System (ADS)

    Woodard, R.; Newman, D. E.; Sánchez, R.; Carreras, B. A.

    2002-12-01

    Characterizing the dynamics of physical systems is a critical first step toward understanding the underlying governing physical processes. In addition to illuminating the physics, characterization helps to evaluate the validity of models that are compared with the physical systems being studied. One such method of characterization is rescaled range analysis. Rescaled range analysis was introduced by Hurst to characterize long time correlations in time series. The rescaled range, R/S, is plotted against the time lag, τ , on doubly logarithmic axes and a single power law is fit to the entire curve. The slope of the plot, which is the exponent in the power law, is called the Hurst exponent, H. The value of H indicates whether the dynamics are persistent (1.0 > H > 0.5), anti-persistent (0.5 > H > 0.0) or uncorrelated (H = 0.5). In his initial report, Hurst found persistence (H ≈ 0.7) in most geophysical data sets that he studied. Self-organized criticality (SOC) was introduced separately (and much later) as a framework for understanding traits commonly seen in many physical systems, such as power laws in power spectra, bursty activity and long time correlations, among others. The running sandpile model was created and defined as a simple and specific example that displays SOC. Persistence in the long time behavior of this model has been indicated by rescaled range analysis, but only up to time lags on the order of 106 for a system of size 102. Power spectra, though, indicate that the dynamics change beyond this time. We have extended the R/S analysis by three orders of magnitude and have seen changes in the dynamics, with consecutive regions that change from persistent to anti-persistent to uncorrelated. This indicates that more than one power law fit to distinct sections of the R/S plot (i.e., more than one value of H) may be appropriate in some systems where different dynamics take place on different time scales. In this work, we put forth an explanation of the

  16. A pan-African medium-range ensemble flood forecast system

    NASA Astrophysics Data System (ADS)

    Thiemig, V.; Bisselink, B.; Pappenberger, F.; Thielen, J.

    2015-08-01

    The African Flood Forecasting System (AFFS) is a probabilistic flood forecast system for medium- to large-scale African river basins, with lead times of up to 15 days. The key components are the hydrological model LISFLOOD, the African GIS database, the meteorological ensemble predictions by the ECMWF (European Centre for Medium-Ranged Weather Forecasts) and critical hydrological thresholds. In this paper, the predictive capability is investigated in a hindcast mode, by reproducing hydrological predictions for the year 2003 when important floods were observed. Results were verified by ground measurements of 36 sub-catchments as well as by reports of various flood archives. Results showed that AFFS detected around 70 % of the reported flood events correctly. In particular, the system showed good performance in predicting riverine flood events of long duration (> 1 week) and large affected areas (> 10 000 km2) well in advance, whereas AFFS showed limitations for small-scale and short duration flood events. The case study for the flood event in March 2003 in the Sabi Basin (Zimbabwe) illustrated the good performance of AFFS in forecasting timing and severity of the floods, gave an example of the clear and concise output products, and showed that the system is capable of producing flood warnings even in ungauged river basins. Hence, from a technical perspective, AFFS shows a large potential as an operational pan-African flood forecasting system, although issues related to the practical implication will still need to be investigated.

  17. Positron Emission Tomography for the Assessment of Myocardial Viability

    PubMed Central

    2005-01-01

    CAD and severe ventricular dysfunction being considered for revascularization that had undergone viability assessment using either PET and/or other noninvasive techniques. The outcomes of interest were diagnostic and predictive accuracy with respect to recovery of regional or global LV function, long-term survival and cardiac events, and quality of life. Other outcomes of interest were impact on treatment decision, adverse events, and cost-effectiveness ratios. Of 456 citations, 8 systematic reviews/meta-analyses and 37 reports on primary studies met the selection criteria. The reports were categorized using the Medical Advisory Secretariat levels of evidence system, and the quality of the reports was assessed using the criteria of the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) developed by the Centre for Dissemination of Research (National Health Service, United Kingdom). Analysis of sensitivity, specificity, predictive values and likelihood ratios were conducted for all data as well as stratified by mean left ventricular ejection fraction (LVEF). There were no randomized controlled trials. The included studies compared PET with one or more other noninvasive viability tests on the same group of patients or examined the long-term outcomes of PET viability assessments. The quality assessment showed that about 50% or more of the studies had selection bias, interpreted tests without blinding, excluded uninterpretable segments in the analysis, or did not have clearly stated selection criteria. Data from the above studies were integrated with data from the 2001 ICES review for analysis and interpretation. Summary of Findings The evidence was derived from populations with moderate to severe ischemic LV dysfunction with an overall quality that ranges from moderate to low. PET appears to be a safe technique for assessing myocardial viability. CAD patients with moderate to severe ischemic LV dysfunction and residual viable myocardium had significantly lower 2

  18. Dead or Alive: Molecular Assessment of Microbial Viability

    PubMed Central

    Meschke, John S.

    2014-01-01

    Nucleic acid-based analytical methods, ranging from species-targeted PCRs to metagenomics, have greatly expanded our understanding of microbiological diversity in natural samples. However, these methods provide only limited information on the activities and physiological states of microorganisms in samples. Even the most fundamental physiological state, viability, cannot be assessed cross-sectionally by standard DNA-targeted methods such as PCR. New PCR-based strategies, collectively called molecular viability analyses, have been developed that differentiate nucleic acids associated with viable cells from those associated with inactivated cells. In order to maximize the utility of these methods and to correctly interpret results, it is necessary to consider the physiological diversity of life and death in the microbial world. This article reviews molecular viability analysis in that context and discusses future opportunities for these strategies in genetic, metagenomic, and single-cell microbiology. PMID:25038100

  19. Optimization of the signal processing in frequency modulated continuous wave laser ranging system

    NASA Astrophysics Data System (ADS)

    Meng, Xiangsong; Zhang, Fumin; Qu, Xinghua

    2015-02-01

    Based on a dual interferometry frequency modulated wave laser (FMCW) laser ranging system, three steps to optimize the signal processing is proposed in this paper. The first step is signal re-sampling, by which the sampling signal is turned to be equal optical frequency intervals. The second step is splicing the re-sampled signal, by which can break though the tuning range of the laser source limitation. The last step is the all-phase pretreatment of the signal, its means that the all-phase Fast Fourier Transformation (apFFT) is used to handle the re-sampled signal, which could reduce the phase error of the signal. The experiments shows that the noise effect due to the tuning nonlinearity of laser can be reduced by re-sampling the signal, 50μm range resolution can be easily obtained by this method, the apFFT is more reliable and effective than FFT in the processing to reduce the phase error and improve the speed of operation.

  20. FEL Beamline for Wide Tunable Range and Beam Sharing System at Kyoto University

    SciTech Connect

    Bakr, Mahmoud; Yoshida, K.; Higashimura, K.; Ueda, S.; Kinjo, R.; Sonobe, T.; Kii, T.; Masuda, K.; Ohgaki, H.; Zen, H.

    2010-02-03

    A mid-infrared free electron laser (MIR-FEL) facility (KU-FEL: Kyoto University Free Electron Laser) has been constructed for developing energy materials in Institute of Advanced Energy (IAE), Kyoto University. The tunable range of KU-FEL was estimated as 5-13.2 {mu}m by numerical calculation to design the MIR-FEL transport line for application purposes. Aiming to increase the number of FEL users with different desires we decided to develop an FEL beam sharing system that is useful for multi-utilization at different end-stations. The transport line and the beam sharing system has been designed and constructed to the user stations. Applications of the MIR-FEL in the renewable energy research at Kyoto University will start as well.

  1. FEL Beamline for Wide Tunable Range and Beam Sharing System at Kyoto University

    NASA Astrophysics Data System (ADS)

    Bakr, Mahmoud; Yoshida, K.; Higashimura, K.; Ueda, S.; Kinjo, R.; Zen, H.; Sonobe, T.; Kii, T.; Masuda, K.; Ohgaki, H.

    2010-02-01

    A mid-infrared free electron laser (MIR-FEL) facility (KU-FEL: Kyoto University Free Electron Laser) has been constructed for developing energy materials in Institute of Advanced Energy (IAE), Kyoto University. The tunable range of KU-FEL was estimated as 5-13.2 μm by numerical calculation to design the MIR-FEL transport line for application purposes. Aiming to increase the number of FEL users with different desires we decided to develop an FEL beam sharing system that is useful for multi-utilization at different end-stations. The transport line and the beam sharing system has been designed and constructed to the user stations. Applications of the MIR-FEL in the renewable energy research at Kyoto University will start as well.

  2. 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.

  3. 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. PMID:27607298

  4. Long-range correlations in degenerate multicomponent systems of charged fermions

    SciTech Connect

    Vericat, F.; Melgarejo, A.A. Instituto de Fisica de Liquidos y Sistemas Bilogicos, Casilla de Correo 565, 1900 La Plata )

    1994-08-01

    The partial structure factors and the pair correlation functions in a degenerate multicomponent system of charged fermions are considered. The long-range behavior of the particle density correlations are specifically analyzed by extending to multicomponent fermionic systems the known properties of the degenerate electron gas (jellium), particularly the long-wavelength limit of the first-moment sum (f-sum). By assuming that this limit is dominated by collective modes, namely, plasmons and phonons, explicit expressions for the leader terms in the correlations are obtained. Based on this dominant asymptotic behavior, we propose effective pair potentials that allow us to incorporate the main quantum effects into a pseudoclassical description of the multicomponent plasma.

  5. Bubble point measurements of the system butane + octylbenzene in the temperature range 290--450 K

    SciTech Connect

    Leeuw, V.V. de; Poot, W.; Loos, T.W. de; Swaan Arons, J. de . Lab. of Applied Thermodynamics and Phase Equilibria)

    1994-01-01

    As a part of research on nitrogen displacement in light-oil reservoirs, the phase behavior of mixtures of a model oil and nitrogen is studied. The model oil consists of methane, butane, and tetradecane or octylbenzene. For reliable phase behavior calculations in the multicomponent system at reservoir conditions -- about 370 K and 50 MPa in the North Sea -- measurements are needed of at least the binary sub-systems in the temperature and pressure range of interest, in order to determine binary interaction coefficients. Bubble points of butane + octylbenzene at eight different mole fractions have been determined at 290--440 K using the synthetic method. The raw experimental data have been fitted using the Peng-Robinson and the Soave-Redlich-Kwong equations of state in combination with a number of different mixing rules.

  6. Nonequilibrium Tricritical Point in a System with Long-Range Interactions

    NASA Astrophysics Data System (ADS)

    Antoniazzi, Andrea; Fanelli, Duccio; Ruffo, Stefano; Yamaguchi, Yoshiyuki Y.

    2007-07-01

    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.

  7. Complex-optical-field lidar system for range and vector velocity measurement.

    PubMed

    Gao, Shuang; O'Sullivan, Maurice; Hui, Rongqing

    2012-11-01

    A coherent lidar system based on the measurement of complex optical field is demonstrated for the first time. An electro-optic in-phase/quadrature (I/Q) modulator is used in the lidar transmitter to realize carrier-suppressed complex optical field modulation in which the positive and the negative optical sidebands can carry independent modulation waveforms. A fiber-optic 90° hybrid is used in the lidar receiver for coherent heterodyne detection and to recover the complex optical field. By loading a constant modulation frequency on the lower optical sideband and a wideband linear frequency chirp on the upper sideband, vector velocity and target distance can be measured independently. The wide modulation bandwidth of this lidar system also enabled unprecedented range resolution and the capability of measuring high velocity unambiguously. PMID:23187404

  8. Clock signal requirement for high-frequency, high dynamic range acquisition systems

    SciTech Connect

    Viscor, Ivo; Halamek, Josef; Villa, Marco

    2005-11-15

    Analog-to-digital converters (ADC's) are increasingly replacing mixers in frequency conversion schemes. To achieve superior performances, in terms of bandwidth and dynamic range, a nearly ideal ADC clock is needed, with a spectral purity higher than the reference signal of the classical mixing scheme. These requirements of spectral purity for the ADC clock are discussed by analyzing in detail the nonuniform sampling process and by characterizing an actual acquisition system. The effect of clock phase imperfections on the output is proportional to the input frequency over sampling frequency ratio. Moreover, at the output we may have a multiple folding of the phase jitter spectrum. These effects are illustrated by three sets of measurements performed using our system: transfer of spurious clock components, aliasing of these components, and transfer of clock phase noise.

  9. Morphological assessment of embryo viability.

    PubMed

    Abeyta, Michael; Behr, Barry

    2014-03-01

    Morphological assessment is discussed in the context of significant literature at all stages of in vitro development, beginning with the oocyte and culminating at the blastocyst stage. Current evidence is used to debate the inclusion of commonly observed morphological features in grading schemes. The biological rationale behind observed phenomena such as multinucleation and fragmentation are also explored. Current limitations as well as technological advancements that increase our ability to assess viability are highlighted. Particular attention is paid to the relationship between developmental timing and assessment schemes. Failure to standardize assessment timing and inclusion criteria is glaring weaknesses of the literature that currently make consensus unattainable. Mounting evidence suggests that the future of static assessment is very likely to be influenced by information gathered from preimplantation genetic screening and other invasive techniques as well as from continuous monitoring tools such as time lapse.

  10. New step toward geodetic range observations at the sea floor with the BBOBS system

    NASA Astrophysics Data System (ADS)

    Shiobara, H.; Shinohara, M.; Isse, T.

    2011-12-01

    Since 1999, we had developed the broadband ocean bottom seismometer (BBOBS) and its new generation model (BBOBS-NX), and performed several practical observations with them in these ten years to create a category of the ocean floor broadband seismology. Now, the BBOBS data is proved to be acceptable for broadband seismic analyses. In these studies, the period range of the data used is about 10 - 200 s, but in longer period range, i.e. geodetic range, is an unknown region in observations at the sea floor. The acoustic GPS link observation is one of successful methods to know horizontal movement of the sea floor, but it is difficult to obtain continuous data in time. The borehole tilt-meter system is ideal in observational conditions, but it is impossible to expand spatially dense observation network. On the other hand, high mobility of our BBOBS and BBOBS-NX can be a breakthrough for this kind of observation network. So that, based on our BBOBS technology, two kinds of attempts to expand observation range toward the geodetic one have been started since 2009. Our aim in these attempts is to extend observation periods more than one week long for detecting slow slip events, as a first step. Finally, we would like to build the observation network by using them. The first attempt is a precise pressure measurement to detect vertical displacement at the sea floor by attaching an absolute pressure gauge and a parasitic data logger to the original OBS data recorder. The stable frequency oscillator (MCXO) in the data recorder is useful for precise pressure measurement of the gauge with frequency outputs. Although the final resolution of the pressure becomes smaller than 1 Pa, we still have problems due to the drift of the gauge and some scale of sea level change in practical observations. The total precision of the pressure value is also affected by the shift and drift of the frequency standard to measure frequency output signals of the gauge. In our measurements, this effect

  11. RTMOD: an Internet based system to analyse the predictions of long-range atmospheric dispersion models

    NASA Astrophysics Data System (ADS)

    Bellasio, Roberto; Bianconi, Roberto; Graziani, Giovanni; Mosca, Sonia

    1999-08-01

    After the Chernobyl accident caused the atmospheric release of radioactive substances that contaminated most of the European territory, the importance of supporting the decisional process in emergency conditions with reliable long-range dispersion models was understood. Generally, the reliability of models is evaluated and verified through comparison against measurements gained during planned experiments or accidental releases. The proper evaluation is based on a set of appropriate statistical indices, each of them giving insight into the specific characteristics of the model. This paper describes an Internet-based system (RTMOD, real time model evaluation) developed to compare in real time, on a graphical and numerical basis, the prediction of several long-range dispersion models. The structure of the system and some examples are presented in the following of this paper. RTMOD was developed to compare model predictions from various 'dry runs' (such as fictitious atmospheric releases), but it can also be used to compare model results against measurements in the situation of an actual release. Hence it is also a useful tool in validating mathematical dispersion models. Moreover, provided that a certain number of models are used, RTMOD becomes also a useful tool in real time managing of accidental releases by indicating the probability that a fixed threshold value will be exceeded, based on the set of model predictions.

  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. Dynamics and physical interpretation of quasistationary states in systems with long-range interactions

    NASA Astrophysics Data System (ADS)

    Rocha Filho, T. M.; Amato, M. A.; Santana, A. E.; Figueiredo, A.; Steiner, J. R.

    2014-03-01

    The time evolution of the one-particle distribution function of an N-particle classical Hamiltonian system with long-range interactions satisfies the Vlasov equation in the limit of infinite N. In this paper we present a new derivation of this result using a different approach allowing a discussion of the role of interparticle correlations on the system dynamics. Otherwise for finite N collisional corrections must be introduced. This has allowed a quite comprehensive study of the quasistationary states (QSSs) though many aspects of the physical interpretations of these states still remain unclear. In this paper a proper definition of time scale for long time evolution is discussed, and several numerical results are presented for different values of N. Previous reports indicate that the lifetimes of the QSS scale as N1.7 or even the system properties scale with exp(N). However, preliminary results presented here indicates that time scale goes as N2 for a different type of initial condition. We also discuss how the form of the interparticle potential determines the convergence of the N-particle dynamics to the Vlasov equation. The results are obtained in the context of the following models: the Hamiltonian mean field, the Self-gravitating ring model, and one- and two-dimensional systems of gravitating particles. We have also provided information of the validity of the Vlasov equation for finite N.

  15. 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

    2015-01-01

    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. PMID:25946627

  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. Fixed-base flywheel storage systems for electric-utility applications: an assessment of economic viability and R and D priorities

    SciTech Connect

    Olszewski, M.; Steele, R.S.

    1983-02-01

    In this study, electric utility-side meter storage options were assessed for the daily 2-h peaking spike application. The storage options considered included compressed air, batteries, and flywheels. The purpose of the study was to assess the potential role for flywheels in this application and to establish research and development (R and D) priorities for fixed-base flywheel systems. Results of the present-worth cost analysis indicate that where geologic conditions are favorable, compressed air energy storage (CAES) is a strong competitor against combustion turbines. Existing battery and flywheel systems rated about equal, both being, at best, marginally uncompetitive with turbines. Advanced batteries, if existing cost and performance goals are met, could be competitive with CAES. A three-task R and D effort for flywheel development appears warranted. The first task, directed at reducing fabrication costs and increasing performance of a chopped fiber, E-glass, solid disk concept, could produce a competitive flywheel system. A second task, directed at S-glass and Kevlar materials, would involve innovations that would permit anisotropic materials (such as Kevlar) to be used in isotropic wheel designs. The third task would be to develop replacements for S-glass and Kevlar that are 30 and 50%, respectively, less costly. The results of this study indicate that a competitive flywheel system for the utility 2-h peaking spike application is possible. It can likely be achieved in the near-term through improvements in an existing design. Potentially less expensive systems are also possible via the successful completion of generic fabrication and materials R and D programs.

  18. The market viability of nuclear hydrogen technologies.

    SciTech Connect

    Botterud, A.; Conzelmann, G.; Petri, M. C.; Yildiz, B.

    2007-04-06

    The Department of Energy Office of Nuclear Energy is supporting system studies to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options within a given market, and identifying the key drivers and thresholds for market viability of nuclear hydrogen options. One of the objectives of the current analysis phase is to determine how nuclear hydrogen technologies could evolve under a number of different futures. The outputs of our work will eventually be used in a larger hydrogen infrastructure and market analysis conducted for DOE-EE using a system-level market simulation tool now underway. This report expands on our previous work by moving beyond simple levelized cost calculations and looking at profitability, risk, and uncertainty from an investor's perspective. We analyze a number of technologies and quantify the value of certain technology and operating characteristics. Our model to assess the profitability of the above technologies is based on Real Options Theory and calculates the discounted profits from investing in each of the production facilities. We use Monte-Carlo simulations to represent the uncertainty in hydrogen and electricity prices. The model computes both the expected value and the distribution of discounted profits from a production plant. We also quantify the value of the option to switch between hydrogen and electricity production in order to maximize investor profits. Uncertainty in electricity and hydrogen prices can be represented with two different stochastic processes: Geometric Brownian Motion (GBM) and Mean Reversion (MR). Our analysis finds that the flexibility to switch between hydrogen and electricity leads to

  19. Improvement spatial resolution of frequency modulated continuous wave laser ranging system by splicing equal optical frequency interval sampled signal

    NASA Astrophysics Data System (ADS)

    Shi, Guang; Zhang, Fumin; Qu, Xinghua

    2015-02-01

    A dual interferometry FMCW laser ranging system is presented. The auxiliary interferometer for generating the clock pulses at equally spaced optical frequencies is incorporated into the main interferometer to simplify the system configuration and to compensate the tuning linearity of the laser source. The need of widely tunable laser limits the practical application of the FMCW laser ranging for precision industrial measurement. Splicing sampled signal method is proposed to break though the tuning range of the laser source limitation against the special resolution. In the experiments, 50 μm range resolution at 8.7 m is demonstrated, and this resolution is maintained over the entire measuring range. The measuring range depending on the power and coherence length of the source can reach more than 20 m. The system structure is simple, and the requirement on the tuning range of laser source is reduced in this system.

  20. Wide-range average temperature measurements of convective fluid flows by using a schlieren system.

    PubMed

    Martínez-González, A; Moreno-Hernández, D; León-Rodríguez, M; Carrillo-Delgado, C

    2016-01-20

    In the schlieren method, the deflection of light by the presence of an inhomogeneous medium is proportional to the gradient of its refractive index. In the presence of temperature variations in a fluid flow, the refraction index is related to the gas density by the Gladstone-Dale constant, which depends on the nature of the gas and the wavelength of light propagating in the medium. The deflection of light in a schlieren system is represented by intensity variations on the observation plane. Then, for a digital camera, the intensity level registered in each pixel depends mainly on the refractive index variation of the medium and exposure time. Therefore, if we regulate the intensity value of each pixel by controlling the exposure time, it is possible to adjust the temperature value measurements. In this way, a specific exposure time of a digital camera allows us to measure a determined range of temperature values. For that reason, in this study we determine the range of temperatures that can be measured with a digital camera for different exposure times. By doing this, a wide range of average temperature value fields can be obtained by summing up the temperature contribution of each exposure time. The basic idea in our approach to measure temperature by using a schlieren system is to relate the intensity level of each pixel in a schlieren image to the corresponding knife-edge position measured at the exit focal plane of the system. Our approach is applied to the measurement of temperature fields of the air convection caused by a heated rectangular metal plate (7.3  cm×12  cm) and a candle flame. We found that the maximum temperature values obtained for exposure times of 31.3, 15.7, 7.9, 3.9, and 2 ms were 67.3°C, 122.6°C, 217.4°C, 364.3°C, and 524.0°C, respectively. PMID:26835931

  1. 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.

  2. Gait measurement system for the multi-target stepping task using a laser range sensor.

    PubMed

    Yorozu, Ayanori; Nishiguchi, Shu; Yamada, Minoru; Aoyama, Tomoki; Moriguchi, Toshiki; Takahashi, Masaki

    2015-01-01

    For the prevention of falling in the elderly, gait training has been proposed using tasks such as the multi-target stepping task (MTST), in which participants step on assigned colored targets. This study presents a gait measurement system using a laser range sensor for the MTST to evaluate the risk of falling. The system tracks both legs and measures general walking parameters such as stride length and walking speed. Additionally, it judges whether the participant steps on the assigned colored targets and detects cross steps to evaluate cognitive function. However, situations in which one leg is hidden from the sensor or the legs are close occur and are likely to lead to losing track of the legs or false tracking. To solve these problems, we propose a novel leg detection method with five observed leg patterns and global nearest neighbor-based data association with a variable validation region based on the state of each leg. In addition, methods to judge target steps and detect cross steps based on leg trajectory are proposed. From the experimental results with the elderly, it is confirmed that the proposed system can improve leg-tracking performance, judge target steps and detect cross steps with high accuracy. PMID:25985161

  3. Out-of-equilibrium fluctuations in stochastic long-range interacting systems

    NASA Astrophysics Data System (ADS)

    Gupta, Shamik; Dauxois, Thierry; Ruffo, Stefano

    2016-03-01

    For a many-particle system with long-range interactions and evolving under stochastic dynamics, we study for the first time the out-of-equilibrium fluctuations of the work done on the system by a time-dependent external force. For equilibrium initial conditions, the work distributions for a given protocol of variation of the force in time and the corresponding time-reversed protocol exhibit a remarkable scaling and a symmetry when expressed in terms of the average and the standard deviation of the work. The distributions of the work per particle predict, by virtue of the Crooks fluctuation theorem, the equilibrium free-energy density of the system. For a large number N of particles, the latter is in excellent agreement with the value computed by considering the Langevin dynamics of a single particle in a self-consistent mean field generated by its interaction with other particles. The agreement highlights the effective mean-field nature of the original many-particle dynamics for large N. For initial conditions in non-equilibrium stationary states (NESSs), we study the distribution of a quantity similar to dissipated work that satisfies the non-equilibrium generalization of the Clausius inequality, namely, the Hatano-Sasa equality, for transitions between NESSs. Besides illustrating the validity of the equality, we show that the distribution has exponential tails that decay differently on the left and on the right.

  4. Gait measurement system for the multi-target stepping task using a laser range sensor.

    PubMed

    Yorozu, Ayanori; Nishiguchi, Shu; Yamada, Minoru; Aoyama, Tomoki; Moriguchi, Toshiki; Takahashi, Masaki

    2015-05-13

    For the prevention of falling in the elderly, gait training has been proposed using tasks such as the multi-target stepping task (MTST), in which participants step on assigned colored targets. This study presents a gait measurement system using a laser range sensor for the MTST to evaluate the risk of falling. The system tracks both legs and measures general walking parameters such as stride length and walking speed. Additionally, it judges whether the participant steps on the assigned colored targets and detects cross steps to evaluate cognitive function. However, situations in which one leg is hidden from the sensor or the legs are close occur and are likely to lead to losing track of the legs or false tracking. To solve these problems, we propose a novel leg detection method with five observed leg patterns and global nearest neighbor-based data association with a variable validation region based on the state of each leg. In addition, methods to judge target steps and detect cross steps based on leg trajectory are proposed. From the experimental results with the elderly, it is confirmed that the proposed system can improve leg-tracking performance, judge target steps and detect cross steps with high accuracy.

  5. Demonstration of micro-projection enabled short-range communication system for 5G.

    PubMed

    Chou, Hsi-Hsir; Tsai, Cheng-Yu

    2016-06-13

    A liquid crystal on silicon (LCoS) based polarization modulated image (PMI) system architecture using red-, green- and blue-based light-emitting diodes (LEDs), which offers simultaneous micro-projection and high-speed data transmission at nearly a gigabit, serving as an alternative short-range communication (SRC) approach for personal communication device (PCD) application in 5G, is proposed and experimentally demonstrated. In order to make the proposed system architecture transparent to the future possible wireless data modulation format, baseband modulation schemes such as multilevel pulse amplitude modulation (M-PAM), M-ary phase shift keying modulation (M-PSK) and M-ary quadrature amplitude modulation (M-QAM) which can be further employed by more advanced multicarrier modulation schemes (such as DMT, OFDM and CAP) were used to investigate the highest possible data transmission rate of the proposed system architecture. The results demonstrated that an aggregative data transmission rate of 892 Mb/s and 900 Mb/s at a BER of 10^(-3) can be achieved by using 16-QAM baseband modulation scheme when data transmission were performed with and without micro-projection simultaneously. PMID:27410326

  6. Bore-Sight Calibration of Multiple Laser Range Finders for Kinematic 3D Laser Scanning Systems

    PubMed Central

    Jung, Jaehoon; Kim, Jeonghyun; Yoon, Sanghyun; Kim, Sangmin; Cho, Hyoungsig; Kim, Changjae; Heo, Joon

    2015-01-01

    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. PMID:25946627

  7. Research on simulation system with the wide range and high-precision laser energy characteristics

    NASA Astrophysics Data System (ADS)

    Dong, Ke-yan; Lou, Yan; He, Jing-yi; Tong, Shou-feng; Jiang, Hui-lin

    2012-10-01

    The Hardware-in-the-loop(HWIL) simulation test is one of the important parts for the development and performance testing of semi-active laser-guided weapons. In order to obtain accurate results, the confidence level of the target environment should be provided for a high-seeker during the HWIL simulation test of semi-active laser-guided weapons, and one of the important simulation parameters is the laser energy characteristic. In this paper, based on the semi-active laser-guided weapon guidance principles, an important parameter of simulation of confidence which affects energy characteristics in performance test of HWIL simulation was analyzed. According to the principle of receiving the same energy by using HWIL simulation and in practical application, HWIL energy characteristics simulation systems with the crystal absorption structure was designed. And on this basis, the problems of optimal design of the optical system were also analyzed. The measured results show that the dynamic attenuation range of the system energy is greater than 50dB, the dynamic attenuation stability is less than 5%, and the maximum energy changing rate driven by the servo motor is greater than 20dB/s.

  8. Gait Measurement System for the Multi-Target Stepping Task Using a Laser Range Sensor

    PubMed Central

    Yorozu, Ayanori; Nishiguchi, Shu; Yamada, Minoru; Aoyama, Tomoki; Moriguchi, Toshiki; Takahashi, Masaki

    2015-01-01

    For the prevention of falling in the elderly, gait training has been proposed using tasks such as the multi-target stepping task (MTST), in which participants step on assigned colored targets. This study presents a gait measurement system using a laser range sensor for the MTST to evaluate the risk of falling. The system tracks both legs and measures general walking parameters such as stride length and walking speed. Additionally, it judges whether the participant steps on the assigned colored targets and detects cross steps to evaluate cognitive function. However, situations in which one leg is hidden from the sensor or the legs are close occur and are likely to lead to losing track of the legs or false tracking. To solve these problems, we propose a novel leg detection method with five observed leg patterns and global nearest neighbor-based data association with a variable validation region based on the state of each leg. In addition, methods to judge target steps and detect cross steps based on leg trajectory are proposed. From the experimental results with the elderly, it is confirmed that the proposed system can improve leg-tracking performance, judge target steps and detect cross steps with high accuracy. PMID:25985161

  9. Long-range-corrected UDFT study on second hyperpolarizabilities of open-shell singlet systems

    NASA Astrophysics Data System (ADS)

    Kishi, Ryohei; Bonness, Sean; Yoneda, Kyohei; Kubo, Takashi; Kamada, Kenji; Ohta, Koji; Champagne, Benoît; Botek, Edith; Tsuneda, Takao; Nakano, Masayoshi

    2012-12-01

    The long-range correction (LC) scheme for the electron exchange in spin-unrestricted density functional theory (DFT), combined with the Becke-Lee-Yang-Parr exchange-correlation functional, i.e., LC-UBLYP, is applied to the calculation of the static second hyperpolarizabilities (γ) of p-quinodimethane, o-dimethylenepyrrole, and o-dimethylenefuran, which have different diradical characters. The spin-unrestricted HF (UHF) and post-UHF electron correlation methods, e.g., spin-unrestricted Mo/ller-Plesset nth-order perturbation theory [UMPn (n = 2, 4)], spinunrestricted coupled cluster singles and doubles (UCCSD) and that with perturbative triples correction [UCCSD(T)] methods as well as the conventional DFT and the spin-flip CI (SF-CI) methods, are applied to the model systems in order to compare the results with that obtained by the LC-UBLYP method. It is found that for the systems having intermediate and large diradical characters, the γ values obtained by the LC-UBLYP method are in good agreement with those obtained by the UCCSD(T) method though it fails to reproduce the UCCSD(T) result for the system with small diradical character.

  10. Centimeter Accuracy for the French Transportable Laser Ranging Station (FTLRS) through Sub-System Controls

    NASA Astrophysics Data System (ADS)

    Nicolas, J.; Pierron, F.; Samain, E.; Barlier, F.

    The French Transportable Laser Ranging Station (FTLRS)is a highly mobile satellite laserranging (SLR) system dedicated to the trackingof geodetic satellites equipped withretroreflectors. This station weighs only 300kg witha 13-cm diameter telescope and is housedin eight containers.The reliability of such a station and its accuracy of 2 cmin real field experiment conditionswere demonstrated during a first field campaign carried outfrom October 1996 to February1997 near Ajaccio on Corsica Island, France. The results ofthis probatory experiment suggestedthat several technical improvements and some modificationswere necessary for JASON-1validation and calibration phase and for new applicationssuch as the Time Transfer by LaserLink (T2L2) experiment. A first change concerns theuse of a new laser wavelength (green instead ofinfrared) and of a new avalanche photodiode with atime walk compensation system. Anotherchange is the installation of a coaxial cabletransmitting directly the signal coming from thereturn detector. Finally, a new calibration systemwas developed with several other changes.A short description of the system is first given.Then, the major changes and the main resultsof ground accuracy tests are summarized and presented.

  11. High-sensitivity cooled coil system for nuclear magnetic resonance in kHz range

    SciTech Connect

    Lin, Tingting; Zhao, Jing; Zhang, Yi; Krause, Hans-Joachim; Lee, Yong-Ho; Lin, Jun

    2014-11-15

    In several low-field Nuclear Magnetic Resonance (LF-NMR) and surface nuclear magnetic resonance applications, i.e., in the frequency range of kHz, high sensitivity magnetic field detectors are needed. Usually, low-T{sub c} superconducting quantum interference devices (SQUIDs) with a high field sensitivity of about 1 fT/Hz{sup 1/2} are employed as detectors. Considering the flux trapping and operational difficulties associated with low-T{sub c} SQUIDs, we designed and fabricated liquid-nitrogen-cooled Cu coils for NMR detection in the kHz range. A cooled coil system consisting of a 9-cm diameter Cu coil and a low noise preamplifier was systematically investigated and reached a sensitivity of 2 fT/Hz{sup 1/2} at 77 K, which is 3 times better compared to the sensitivity at 300 K. A Q-switch circuit as an essential element for damping the ringing effects of the pickup coil was developed to acquire free induction decay signals of a water sample with minimum loss of signal. Our studies demonstrate that cooled Cu coils, if designed properly, can provide a comparable sensitivity to low-T{sub c} SQUIDs.

  12. Robust Dead Reckoning System for Mobile Robots Based on Particle Filter and Raw Range Scan

    PubMed Central

    Duan, Zhuohua; Cai, Zixing; Min, Huaqing

    2014-01-01

    Robust dead reckoning is a complicated problem for wheeled mobile robots (WMRs), where the robots are faulty, such as the sticking of sensors or the slippage of wheels, for the discrete fault models and the continuous states have to be estimated simultaneously to reach a reliable fault diagnosis and accurate dead reckoning. Particle filters are one of the most promising approaches to handle hybrid system estimation problems, and they have also been widely used in many WMRs applications, such as pose tracking, SLAM, video tracking, fault identification, etc. In this paper, the readings of a laser range finder, which may be also interfered with by noises, are used to reach accurate dead reckoning. The main contribution is that a systematic method to implement fault diagnosis and dead reckoning in a particle filter framework concurrently is proposed. Firstly, the perception model of a laser range finder is given, where the raw scan may be faulty. Secondly, the kinematics of the normal model and different fault models for WMRs are given. Thirdly, the particle filter for fault diagnosis and dead reckoning is discussed. At last, experiments and analyses are reported to show the accuracy and efficiency of the presented method. PMID:25192318

  13. Laser ranging system and measurement analysis for space debris with high repetition rate

    NASA Astrophysics Data System (ADS)

    Wu, Zhibo; Zhang, Haifeng; Meng, Wendong; Li, Pu; Deng, Huarong; Tang, Kai; Ding, Renjie; Zhang, Zhongping

    2016-01-01

    Laser measurement technology is inherently high accurate and will play an important role in precise orbit determination, accurate catalog, surveillance to space debris. Shanghai Astronomical Observatory (SHAO) has been developing the technology of laser measurement to space debris for several years. Based on the first successful laser ranging measurement to space debris in country, by applying one new set of high power 532nm wavelength laser system with 200Hz repetition rate, and adopting low dark noise APD detector with high quantum efficiency and high transmissivity of narrow bandwidth spectral filter, SHAO have achieved hundreds of passes of laser data from space debris in 2014, and the measured objects with distance between 500km and 2200km, Radar Cross Section (RCS) of >10m2 to <0.5m2 at the precision of <1m RMS for small RCS targets ,and the success rate of measured passes of up to 80%. The results show that laser ranging technology in China can routinely measure space debris and provide enough measurement data with high accuracy to space debris applications and researches such as surveillance activities in the future.

  14. Robust dead reckoning system for mobile robots based on particle filter and raw range scan.

    PubMed

    Duan, Zhuohua; Cai, Zixing; Min, Huaqing

    2014-09-04

    Robust dead reckoning is a complicated problem for wheeled mobile robots (WMRs), where the robots are faulty, such as the sticking of sensors or the slippage of wheels, for the discrete fault models and the continuous states have to be estimated simultaneously to reach a reliable fault diagnosis and accurate dead reckoning. Particle filters are one of the most promising approaches to handle hybrid system estimation problems, and they have also been widely used in many WMRs applications, such as pose tracking, SLAM, video tracking, fault identification, etc. In this paper, the readings of a laser range finder, which may be also interfered with by noises, are used to reach accurate dead reckoning. The main contribution is that a systematic method to implement fault diagnosis and dead reckoning in a particle filter framework concurrently is proposed. Firstly, the perception model of a laser range finder is given, where the raw scan may be faulty. Secondly, the kinematics of the normal model and different fault models for WMRs are given. Thirdly, the particle filter for fault diagnosis and dead reckoning is discussed. At last, experiments and analyses are reported to show the accuracy and efficiency of the presented method.

  15. Earth strain measurements with the transportable laser ranging system: Field techniques and planning

    NASA Technical Reports Server (NTRS)

    Nakamura, Y.; Dorman, H. J.; Cahill, T.

    1982-01-01

    The potential of the transportable laser ranging system for monitoring the ground deformation around satellite ranging stations and other geodetic control points was examined with emphasis on testing the usefulness of the relative alteration technique. The temporal variation of the ratio of the length of each survey line to the mean length of all survey lines in a given area is directly related to the mean shear strain rate for the area. The data from a series of experimental measurements taken over the Los Angeles basin from a TLRS station at Mt. Wilson show that such ratios can be determined to an accuracy of one part in 10 million with a measurement program lasting for three days and without using any corrections for variations in atmospheric conditions. A numerical experiment using a set of hypothetical data indicates that reasonable estimates of the present shear strain rate and the direction of the principal axes in southern California can be deduced from such measurements over an interval of one to two years.

  16. Minimal mechanism leading to discontinuous phase transitions for short-range systems with absorbing states

    NASA Astrophysics Data System (ADS)

    Fiore, Carlos E.

    2014-02-01

    Motivated by recent findings, we discuss the existence of a direct and robust mechanism providing discontinuous absorbing transitions in short-range systems with single species, with no extra symmetries or conservation laws. We consider variants of the contact process, in which at least two adjacent particles (instead of one, as commonly assumed) are required to create a new species. Many interaction rules are analyzed, including distinct cluster annihilations and a modified version of the original pair contact process. Through detailed time-dependent numerical simulations, we find that for our modified models, the phase transitions are of first order, hence contrasting with their corresponding usual formulations in the literature, which are of second order. By calculating the order-parameter distributions, the obtained bimodal shapes as well as the finite-scale analysis reinforce coexisting phases and thus a discontinuous transition. These findings strongly suggest that the above particle creation requirements constitute a minimum and fundamental mechanism determining the phase coexistence in short-range contact processes.

  17. Pedestrian mobile mapping system for indoor environments based on MEMS IMU and range camera

    NASA Astrophysics Data System (ADS)

    Haala, N.; Fritsch, D.; Peter, M.; Khosravani, A. M.

    2011-12-01

    This paper describes an approach for the modeling of building interiors based on a mobile device, which integrates modules for pedestrian navigation and low-cost 3D data collection. Personal navigation is realized by a foot mounted low cost MEMS IMU, while 3D data capture for subsequent indoor modeling uses a low cost range camera, which was originally developed for gaming applications. Both steps, navigation and modeling, are supported by additional information as provided from the automatic interpretation of evacuation plans. Such emergency plans are compulsory for public buildings in a number of countries. They consist of an approximate floor plan, the current position and escape routes. Additionally, semantic information like stairs, elevators or the floor number is available. After the user has captured an image of such a floor plan, this information is made explicit again by an automatic raster-to-vector-conversion. The resulting coarse indoor model then provides constraints at stairs or building walls, which restrict the potential movement of the user. This information is then used to support pedestrian navigation by eliminating drift effects of the used low-cost sensor system. The approximate indoor building model additionally provides a priori information during subsequent indoor modeling. Within this process, the low cost range camera Kinect is used for the collection of multiple 3D point clouds, which are aligned by a suitable matching step and then further analyzed to refine the coarse building model.

  18. Rapid resolution of crustal motion at short ranges with the global positioning system

    NASA Technical Reports Server (NTRS)

    Genrich, Joachim F.; Bock, Yehuda

    1992-01-01

    An analysis of GPS alignment array data collected in November 1990 and February 1991 are used to assess the temporal resolution of crustal deformation for GPS receiver systems operating as strain meters, and guidelines for achieving millimeter-level precision with short-range, kinematic-type GPS measurements are provided. Baselines between the array endpoints computed from 24 min of static observations on three consecutive days show an rms scatter of about 0.1 nm in the horizontal components and of about 0.3 mm in the vertical. They agree to within 0.2 mm with a solution calculated from measurements collected 3 mo earlier, indicating that this segment of the San Andreas fault appears to be locked at the surface over this period of time. Epoch-by-epoch solutions of array baselines with a six-satellite constellation show a multipath signature with typical amplitudes of several millimeters and periods of a few minutes.

  19. The range of options for handling plane angle and solid angle within a system of units

    NASA Astrophysics Data System (ADS)

    Quincey, Paul

    2016-04-01

    The radian and steradian are unusual units within the SI, originally belonging to their own category of ‘supplementary units’, with this status being changed to dimensionless ‘derived units’ in 1995. Recent papers have suggested that angles could be handled in two different ways within the SI, both differing from the present system. The purpose of this paper is to provide a framework for putting such suggestions into context, outlining the range of options that is available, together with the advantages and disadvantages of these options. Although less rigorously logical than some alternatives, the present SI approach is generally supported, but with some changes to the SI brochure to make the position clearer, in particular with regard to the designation of the radian and steradian as derived units.

  20. An advanced energy management system for controlling the ultracapacitor discharge and improving the electric vehicle range

    NASA Astrophysics Data System (ADS)

    Armenta, Jesús; Núñez, Ciro; Visairo, Nancy; Lázaro, Isabel

    2015-06-01

    Over the last years issues regarding both the use and the improvement of energy management in electric vehicles have been highlighted by industry and academic fields. Some of the research has been focused on exploiting the ultracapacitor characteristics and on protecting the battery life. From this standpoint, this paper proposes an advanced energy management system based on the adequate discharge of the ultracapacitor bank in order to utilize all the energy available from the regenerative breaking. In this way, the energy consumption is reduced and the electric vehicle range is increased. This strategy, based on simple rules, takes advantage of the high power density of the ultracapacitor and prevents an overstress of the battery. The benefits are featured using three standard drive cycles for a 1550 kg electric vehicle via simulations.

  1. Evaluation of a thermistior power measurement system for use on the NPL antenna extrapolation range

    NASA Astrophysics Data System (ADS)

    Gentle, D. G.

    1990-05-01

    A series of tests designed to evaluate the thermistor power meters for use on the antenna extrapolation range are summarized. These power meters are used to measure the insertion loss as the separation between the antenna is increased. Procedures were written in PASCAL to read the DVM (Drive Voltage Meter) connected to the power meters via the IEEE-488 interface bus. Once these procedures were optimized for speed and accuracy, two thermistor power meters were used to measure the attenuation of a WG 16 rotary vane attenuator. This attenuator was then calibrated against the NPL (National Physics Laboratory) Mark 1 waveguide beyond cutoff attenuator and the performance of the thermistor power meter system was assessed. The uncertainties quoted are at the 95 percent confidence level unless they relate to the accuracy of DVMs, in which case they are 3 sigma values.

  2. Expansion of range of joint motion following treatment of systemic sclerosis with tocilizumab.

    PubMed

    Shima, Yoshihito; Hosen, Naoki; Hirano, Toru; Arimitsu, Junsuke; Nishida, Sumiyuki; Hagihara, Keisuke; Narazaki, Masashi; Ogata, Atsushi; Tanaka, Toshio; Kishimoto, Tadamitsu; Kumanogoh, Atsushi

    2015-01-01

    Systemic sclerosis (SSc) presents stiffness of extremities due to sclerosis of the tissue especially at fingers, hands, and forearms. Here we report the case of a patient with diffuse cutaneous SSc who was administered anti-interleukin-6 receptor antibody tocilizumab (TCZ). Skin condition of SSc is evaluated by pinching the skin according to the Rodnan skin score, but sometimes tissue atrophy results in overestimation of the condition. To understand how the extremities softened after initiation of TCZ, we observed mobility of extremities. Range of motion (ROM) of joints was measured every four months after initiation of TCZ. The patient presented not only reduction of Rodnan score but also amelioration of mobility of extremities. The Rodnan skin score reduced from 35 to 7 within sixteen months, and ROM of most joints except ankle was expanded.

  3. The effects of atmospheric refraction on the accuracy of laser ranging systems

    NASA Technical Reports Server (NTRS)

    Zanter, D. L.; Gardner, C. S.; Rao, N. N.

    1976-01-01

    Correction formulas derived by Saastamoinen and Marini, and the ray traces through the refractivity profiles all assume a spherically symmetric refractivity profile. The errors introduced by this assumption were investigated by ray tracing through three-dimensional profiles. The results of this investigation indicate that the difference between ray traces through the spherically symmetric and three-dimensional profiles is approximately three centimeters at 10 deg and decreases to less than one half of a centimeter at 80 deg. If the accuracy desired in future laser ranging systems is less than a few centimeters, Saastamoinen and Marini's formulas must be altered to account for the fact that the refractivity profile is not spherically symmetric.

  4. A study of engine variable geometry systems for an advanced high subsonic long range commercial aircraft

    NASA Technical Reports Server (NTRS)

    Compagnon, M. A.

    1973-01-01

    Several variable geometry high Mach inlet concepts, aimed at meeting a system noise objective of 15 EPNdB below FAR part 36, for a long range, Mach 0.9 advanced commercial transport are assessed and compared to a fixed geometry inlet with multiple splitters. The effects of a variable exhaust nozzle (mixed exhaust engine) on noise, inlet geometry requirements, and economics are also presented. The best variable geometry inlet configuration identified is a variable cowl design which relies on a high throat Mach number for additional inlet noise suppression only at takeoff, and depends entirely on inlet wall treatment for noise suppression at approach power. Relative economic penalties as a function of noise level are also presented.

  5. Very-short range forecasting system for 2018 Pyeonchang Winter Olympic and Paralympic games

    NASA Astrophysics Data System (ADS)

    Nam, Ji-Eun; Park, Kyungjeen; Kim, Minyou; Kim, Changhwan; Joo, Sangwon

    2016-04-01

    The 23rd Olympic Winter and the 13th Paralympic Winter Games will be held in Pyeongchang, Republic of Korea respectively from 9 to 25 February 2018 and from 9 to 18 February 2018. The Korea Meteorological Administration (KMA) and the National Institute for Meteorological Science (NIMS) have the responsibility to provide weather information for the management of the Games and the safety of the public. NIMS will carry out a Forecast Demonstration Project (FDP) and a Research and Development Project (RDP) which will be called ICE-POP 2018. These projects will focus on intensive observation campaigns to understand severe winter weathers over the Pyeongchang region, and the research results from the RDP will be used to improve the accuracy of nowcasting and very short-range forecast systems during the Games. To support these projects, NIMS developed Very-short range Data Assimilation and Prediction System (VDAPS), which is run in real time with 1 hour cycling interval and up to 12 hour forecasts. The domain is covering Korean Peninsular and surrounding seas with 1.5km horizontal resolution. AWS, windprofiler, buoy, sonde, aircraft, scatwinds, and radar radial winds are assimilated by 3DVAR on 3km resolution inner domain. The rain rate is converted into latent heat and initialized via nudging. The visibility data are also assimilated with the addition of aerosol control variable. The experiments results show the improvement in rainfall over south sea of Korean peninsula. In order to reduce excessive rainfalls during first 2 hours due to the reduced cycling interval, the data assimilation algorithm is optimized.

  6. Ranging airport pseudolite for local area augmentation using the global positioning system

    NASA Astrophysics Data System (ADS)

    Bartone, Chris Gregory

    The Local Area Augmentation System (LAAS) is being developed to support precision approach and landing operations in and about the local area surrounding an airport. The LAAS Program is currently under development by the Federal Aviation Administration (FAA) with Minimum Aviation System Performance Standards for the LAAS being developed by RTCA, Incorporated. The LAAS uses differential Global Positioning System (DGPS) and includes one or more airport pseudolites (APL) to increase the availability for certain installations. This dissertation addresses the addition of a differentially corrected, ranging APL into a LAAS. Prior to this work, no ranging APL has been integrated into a prototype LAAS and demonstrated in a real-time flight environment showing that an increase in LAAS availability is feasible. The APL requirements resulted in a prototype APL transmitting and receiving subsystem with a coarse-acquisition (C/A) code format that could be operated at any frequency within the L1± 10.0 MHz band. To investigate the major APL error the developmental approach was performed in two phases. Phase I implemented an APL operating at a center frequency off-L1 and concentrated on multipath limiting. The Phase II on-L1 APL architecture implemented a unique pulsing, automatic gain control (AGC) and GPS Blanker technique in the common reception path to maximize APL signal tracking and minimize electromagnetic interference to DGPS. To minimize ground multipath for the APL geometry, which is more severe than for GPS, a multipath limiting antenna (MLA) was designed, fabricated, and tested within a 4-month period. The implementation of this MLA concept was a first for APL applications and also contributed to the successful multipath limiting of ground multipath at the DGPS LAAS Ground Station. This effort successfully demonstrated that ground multipath can be limited (with low variance and no long-term bias) for the APL geometry and that suitable precision approach performance

  7. Among substituted 9,10-dihydro-9,10-[1,2]benzenoanthracene-1,4,5,8-tetraones, the lead antitumor triptycene bisquinone TT24 blocks nucleoside transport, induces apoptotic DNA fragmentation and decreases the viability of L1210 leukemic cells in the nanomolar range of daunorubicin in vitro.

    PubMed

    Perchellet, Elisabeth M; Sperfslage, Bonnie J; Wang, Yang; Huang, Xiaodong; Tamura, Masafumi; Hua, Duy H; Perchellet, Jean-Pierre

    2002-07-01

    In contrast to their inactive parent compound triptycene (code name TT0), several new synthetic analogs (TT code number) have antileukemic activities and remain effective in daunorubicin (DAU)-resistant tumor sublines in vitro. Among variously substituted 9,10-dihydro-9,10-[1,2]benzenoanthracene-1,4,5,8-tetraones, a total of six lead antitumor compounds have been identified, and their code names are TT2, TT13, TT16, TT19, TT21 and TT24. These active antitumor triptych structures have bisquinone functionality, and various bromo, methoxy, methylamino and/or dimethylamino substitutions with or without longer alkyl chains on the amino function. Like the anthracycline quinone antibiotic DAU, these triptycene (TT) bisquinones also inhibit DNA synthesis and induce DNA cleavage in relation with their cytotoxic activities, but have the additional advantage of blocking the cellular transport of purine and pyrimidine nucleosides, an effect which DAU cannot do. As demonstrated by intact chromatin precipitation and agarose gel electrophoresis, the ability of TT bisquinones and DAU to induce DNA fragmentation is biphasic with a peak that shifts to lower concentrations with increasing times of drug exposure. The most effective lead antitumor compound, TT24, induces DNA cleavage in the same concentration-dependent manner as DAU at 24 h (similar peak in response to 1.6 microM) and is nearly equipotent to DAU against L1210 tumor cell viability at day 4 (IC50 values of TT24 and DAU: 48 and 25 nM, respectively). The mechanism by which TT24 induces DNA fragmentation is inhibited by actinomycin D, cycloheximide, benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone, benzyloxycarbonyl-Ile-Glu-Thr-Asp-fluoromethyl ketone, N-tosyl-L-phenylalanine chloromethyl ketone and ZnSO4, suggesting that TT bisquinones trigger apoptosis by caspase and endonuclease activation. Since TT24 is cytotoxic in the nanomolar range of DAU, but might have a more versatile mechanism of action than DAU in wild

  8. a Field-Theoretical Investigation of 2-D Coulomb Systems with Short-Range Yukawa Repulsion.

    NASA Astrophysics Data System (ADS)

    Jargocki, Krzysztof Piotr

    The two-dimensional Coulomb gas, consisting of positive and negative charges, is an important system which, on one hand, is equivalent to the vortex sector of the planar X-Y model, and, on the other, to the sine-Gordon field theory. In most treatments the charged particles are assumed to have a repulsive hard core which prevents arbitrarily close approaches. In the present work a new regularization scheme based on a soft short-range Yukawa repulsion between the Coulomb gas particles is presented. This formulation is transcribed into a local sine-Gordon-like field theory involving two Bose fields, one the original massless sine -Gordon field corresponding to the long-range Coulomb interaction and an auxiliary massive field corresponding to the short -range Yukawa repulsion. The resulting Lagrangian is not Hermitian. Using the techniques of functional integration, an effective field theory involving the Coulomb field alone is obtained by integrating out the massive field. The resulting Lagrangian is now Hermitian. Then a generalization of Peierls' inequality is used to make a variational calculation of the ground state energy of the Coulomb system. Unlike in the pure sine-Gordon case the theory has a well-defined ground state energy for (beta)q('2) > 2 (or (beta)c('2) > 8(pi)). A new method is used to derive the Kosterlitz -Thouless renormalization group equations, starting with the original sine-Gordon-like theory. The equations are identical to those found previously by other authors. A wave function renormalization is found to be necessary in addition to the normal ordering discussed by Coleman. A fermionized version of the theory is obtained, using the dictionary provided by Kogut and Susskind, which involves two Fermi fields and an electromagnetic potential. Position -space correlation functions are calculated at the critical point. The effective potential is computed in the one -loop approximation. A nonlinear field theory with derivative couplings is found to

  9. Metabolomic assessment of embryo viability.

    PubMed

    Uyar, Asli; Seli, Emre

    2014-03-01

    Preimplantation embryo metabolism demonstrates distinctive characteristics associated with the developmental potential of embryos. On this basis, metabolite content of culture media was hypothesized to reflect the implantation potential of individual embryos. This hypothesis was tested in consecutive studies reporting a significant association between culture media metabolites and embryo development or clinical pregnancy. The need for a noninvasive, reliable, and rapid embryo assessment strategy promoted metabolomics studies in vitro fertilization (IVF) in an effort to increase success rates of single embryo transfers. With the advance of analytical techniques and bioinformatics, commercial instruments were developed to predict embryo viability using spectroscopic analysis of surplus culture media. However, despite the initial promising results from proof-of-principal studies, recent randomized controlled trials using commercial instruments failed to show a consistent benefit in improving pregnancy rates when metabolomics is used as an adjunct to morphology. At present, the application of metabolomics technology in clinical IVF laboratory requires the elimination of factors underlying inconsistent findings, when possible, and development of reliable predictive models accounting for all possible sources of bias throughout the embryo selection process. PMID:24515909

  10. Micro-organism and cell viability on antimicrobially modified titanium.

    PubMed

    Omori, S; Shibata, Y; Arimoto, T; Igarashi, T; Baba, K; Miyazaki, T

    2009-10-01

    When titanium is anodized by discharge in NaCl solution, both antimicrobial activity and osteoconductivity are conferred. The viability of adherent micro-organisms and cells on antimicrobial titanium remains uncertain. We hypothesized that a thin peroxidation barrier would efficiently destroy adherent bacteria, whereas adherent osteoblastic cells would be viable, since these cells adhere to the surface indirectly though serum proteins. The efficacy of antimicrobial titanium appears to be based on peroxidation, since peroxidation products were detected in parallel with the destruction of bacterial cell-surface structures. The peroxidation effect of antimicrobial titanium was confined to the surface within narrow limits. The viability of osteoblastic cells on the surface was strongly dependent on the presence of serum protein, whereas that of adherent Streptococcus mutans was not affected by the presence of serum proteins. Therefore, differences in the adherent systems used by bacteria and osteoblastic cells are important determinants of their viability on antimicrobial titanium.

  11. Solar energy system economic evaluation for IBM system 1B, Carlsbad, New Mexico

    NASA Technical Reports Server (NTRS)

    1980-01-01

    The economic performance of an operational test site of a solar energy system is described. The viability of the system was tested over a broad range of environmental and economic conditions. Significant results are reported.

  12. Non-equilibrium entropy and dynamics in a system with long-range interactions

    NASA Astrophysics Data System (ADS)

    Rocha Filho, T. M.

    2016-05-01

    We extend the core-halo approach of Levin et al (2014 Phys. Rep. 535, 1) for the violent relaxation of long-range interacting system with a waterbag initial condition, in the case of a widely studied Hamiltonian mean field model. The Gibbs entropy maximization principle is considered with the constraints of energy conservation and of coarse-grained Casimir invariants of the Vlasov equation. The core-halo distribution function depends only on the one-particle mean-field energy, as is expected from the Jeans theorem, and depends on a set of parameters which in our approach is completely determined without having to solve an envelope equation for the contour of the initial state, as required in the original approach. We also show that a different ansatz can be used for the core-halo distribution with similar results. This work also reveals a link between a parametric resonance causing the non-equilibrium phase transition in the model, a dynamical property, and a discontinuity of the (non-equilibrium) entropy of the system.

  13. Generalized maximum entropy approach to quasistationary states in long-range systems

    NASA Astrophysics Data System (ADS)

    Martelloni, Gabriele; Martelloni, Gianluca; de Buyl, Pierre; Fanelli, Duccio

    2016-02-01

    Systems with long-range interactions display a short-time relaxation towards quasistationary states (QSSs) whose lifetime increases with the system size. In the paradigmatic Hamiltonian mean-field model (HMF) out-of-equilibrium phase transitions are predicted and numerically detected which separate homogeneous (zero magnetization) and inhomogeneous (nonzero magnetization) QSSs. In the former regime, the velocity distribution presents (at least) two large, symmetric bumps, which cannot be self-consistently explained by resorting to the conventional Lynden-Bell maximum entropy approach. We propose a generalized maximum entropy scheme which accounts for the pseudoconservation of additional charges, the even momenta of the single-particle distribution. These latter are set to the asymptotic values, as estimated by direct integration of the underlying Vlasov equation, which formally holds in the thermodynamic limit. Methodologically, we operate in the framework of a generalized Gibbs ensemble, as sometimes defined in statistical quantum mechanics, which contains an infinite number of conserved charges. The agreement between theory and simulations is satisfying, both above and below the out-of-equilibrium transition threshold. A previously unaccessible feature of the QSSs, the multiple bumps in the velocity profile, is resolved by our approach.

  14. The Lunar Gravity Ranging System for the Gravity Recovery and Interior Laboratory (GRAIL) Mission

    NASA Astrophysics Data System (ADS)

    Klipstein, William M.; Arnold, Bradford W.; Enzer, Daphna G.; Ruiz, Alberto A.; Tien, Jeffrey Y.; Wang, Rabi T.; Dunn, Charles E.

    2013-09-01

    The Lunar Gravity Ranging System (LGRS) flying on NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission measures fluctuations in the separation between the two GRAIL orbiters with sensitivity below 0.6 microns/Hz1/2. GRAIL adapts the mission design and instrumentation from the Gravity Recovery and Climate Experiment (GRACE) to a make a precise gravitational map of Earth's Moon. Phase measurements of Ka-band carrier signals transmitted between spacecraft with line-of-sight separations between 50 km to 225 km provide the primary observable. Measurements of time offsets between the orbiters, frequency calibrations, and precise orbit determination provided by the Global Positioning System on GRACE are replaced by an S-band time-transfer cross link and Deep Space Network Doppler tracking of an X-band radioscience beacon and the spacecraft telecommunications link. Lack of an atmosphere at the Moon allows use of a single-frequency link and elimination of the accelerometer compared to the GRACE instrumentation. This paper describes the implementation, testing and performance of the instrument complement flown on the two GRAIL orbiters.

  15. Long-range interactions and the sign of natural amplitudes in two-electron systems

    SciTech Connect

    Giesbertz, Klaas J. H.; Leeuwen, Robert van

    2013-09-14

    In singlet two-electron systems, the natural occupation numbers of the one-particle reduced density matrix are given as squares of the natural amplitudes which are defined as the expansion coefficients of the two-electron wave function in a natural orbital basis. In this work, we relate the sign of the natural amplitudes to the nature of the two-body interaction. We show that long-range Coulomb-type interactions are responsible for the appearance of positive amplitudes and give both analytical and numerical examples that illustrate how the long-distance structure of the wave function affects these amplitudes. We further demonstrate that the amplitudes show an avoided crossing behavior as function of a parameter in the Hamiltonian and use this feature to show that these amplitudes never become zero, except for special interactions in which infinitely many of them can become zero simultaneously when changing the interaction strength. This mechanism of avoided crossings provides an alternative argument for the non-vanishing of the natural occupation numbers in Coulomb systems.

  16. Compensation electronics for larger dynamic range of a SQUID based nondestructive evaluation system

    NASA Astrophysics Data System (ADS)

    Kreutzbruck, M. v.; Theiss, A.; Mück, M.; Heiden, C.

    1999-09-01

    We have developed a compensation system for any given SQUID sensor which allows sensitive eddy current measurements above 100 Hz in the presence of strong and slowly varying background fields. High Tc SQUIDs have been used successfully in nondestructive evaluation (NDE) systems based on eddy current excitation when searching for defects in conductive samples such as aircraft parts. Due to their high and frequency independent field resolution and their excellent spatial resolution, SQUIDs provide in the case of deep lying defects—compared to other conventional electromagnetic NDE systems—a more reliable crack detection. Fast readout electronics having an unsurpassed dynamic range of up to eight orders of magnitude enabled us to perform measurements in an environment polluted with electromagnetic noise, e.g., an aircraft hangar. Nevertheless, test objects containing ferromagnetic structures with a high remanent magnetization, such as aircraft wheels or steel bolts in an aircraft wing, very often cause instabilities of the flux-locked loop operation of the SQUID. To prevent unlocking, we have developed a new background field compensation scheme. Special compensation electronics take care of slowly varying magnetic fields of up to 1 mT/s and allow us to perform eddy current measurements in the presence of slow (<30 Hz) background field variations of up to 5 mT.

  17. Absolute stability and spatiotemporal long-range order in Floquet systems

    NASA Astrophysics Data System (ADS)

    von Keyserlingk, C. W.; Khemani, Vedika; Sondhi, S. L.

    2016-08-01

    Recent work has shown that a variety of novel phases of matter arise in periodically driven Floquet systems. Among these are many-body localized phases which spontaneously break global symmetries and exhibit novel multiplets of Floquet eigenstates separated by quantized quasienergies. Here we show that these properties are stable to all weak local deformations of the underlying Floquet drives—including those that explicitly break the defining symmetries—and that the models considered until now occupy submanifolds within these larger "absolutely stable" phases. While these absolutely stable phases have no explicit global symmetries, they spontaneously break Hamiltonian-dependent emergent symmetries, and thus continue to exhibit the novel multiplet structure. The multiplet structure in turn encodes characteristic oscillations of the emergent order parameter at multiples of the fundamental period. Altogether these phases exhibit a form of simultaneous long-range order in space and time which is new to quantum systems. We describe how this spatiotemporal order can be detected in experiments involving quenches from a broad class of initial states.

  18. crop and range alert system in the U.S. northern Great Plains

    NASA Astrophysics Data System (ADS)

    Seelan, Santhosh K.; Beeri, Ofer; Baumgardner, David; Casady, Grant; Laguette, Soizik; Seielstad, George

    2003-03-01

    The Upper Midwest Aerospace Consortium has developed a crop and range alert system to provide farmers, ranchers, land managers from the Native American Community, government agencies and non-governmental organizations with frequent and near real time remote sensing data to enable decisions that both maximize the producer's income and protect the environment. The project, started in 1999, includes the establishment of a learning community network of end users, fast delivery of data to remote locations, applications development and training. More than a hundred and fifty end users and research scientists participated in this learning group in which information is shared in all directions. Over fifty end users were connected via high-bandwidth satellite link to a central distribution system at the University of North Dakota. They received and shared products derived from AVHRR, MODIS, Landsat, IKONOS and aerial platforms. A number of practical applications were developed for precision farming, such as zone-based nitrogen management, stress detection, spray drift detection, and for rangeland management, such as weed detection, livestock carrying capacity, and livestock field rotations. Several instances of cost savings and higher earnings occurred. More importantly, the imagery use resulted in lesser use of chemicals in farming and ranching, leading to environmental benefits.

  19. A fast job scheduling system for a wide range of bioinformatic applications.

    PubMed

    Boccia, Angelo; Busiello, Gianluca; Milanesi, Luciano; Paolella, Giovanni

    2007-06-01

    Bioinformatic tools are often used by researchers through interactive Web interfaces, resulting in a strong demand for computational resources. The tools are of different kind and range from simple, quick tasks, to complex analyses requiring minutes to hours of processing time and often longer than that. Batteries of computational nodes, such as those found in parallel clusters, provide a platform of choice for this application, especially when a relatively large number of concurrent requests is expected. Here, we describe a scheduling architecture operating at the application level, able to distribute jobs over a large number of hierarchically organized nodes. While not contrasting and peacefully living together with low-level scheduling software, the system takes advantage of tools, such as SQL servers, commonly used in Web applications, to produce low latency and performance which compares well and often surpasses that of more traditional, dedicated schedulers. The system provides the basic functionality necessary to node selection, task execution and service management and monitoring, and may combine loosely linked computational resources, such as those located in geographically distinct sites. PMID:17695750

  20. Low-level waste vitrification contact maintenance viability study

    SciTech Connect

    Leach, C.E., Westinghouse Hanford

    1996-07-12

    This study investigates the economic viability of contact maintenance in the Low-Level Waste Vitrification Facility, which is part of the Hanford Site Tank Waste Remediation System. This document was prepared by Flour Daniel, Inc., and transmitted to Westinghouse Hanford Company in September 1995.

  1. Highly modular high-brightness diode laser system design for a wide application range

    NASA Astrophysics Data System (ADS)

    Fritsche, Haro; Kruschke, Bastian; Koch, Ralf; Ferrario, Fabio; Kern, Holger; Pahl, Ullrich; Ehm, Einar; Pflueger, Silke; Grohe, Andreas; Gries, Wolfgang

    2015-03-01

    For an economic production it is important to serve as many applications as possible while keeping the product variations minimal. We present our modular laser design, which is based on single emitters and various combining technics. In a first step we accept a reduction of the very high brightness of the single emitters by vertical stacking. Those emitters can be wavelength stabilized by an external resonator, providing the very same feedback to each of those laser diodes which leads to an output power of about 100W with BPP of <3.5 mm*mrad (FA) and <5 mm*mrad (SA). Further power scaling is accomplished by polarization and wavelength multiplexing yielding high optical efficiencies of more than 80% and results in about 500 W launched into a 100 μm fiber with 0.15 NA. Subsequently those building blocks can be stacked also by the very same dense spectral combing technique up to multi kW Systems without further reduction of the BPP. These "500W building blocks" are consequently designed in a way that without any system change new wavelengths can be implemented by only exchanging parts but without change of the production process. This design principal offers the option to adapt the wavelength of those blocks to any applications, from UV, visible into the far IR. From laser pumping and scientific applications to materials processing such as cutting and welding of copper aluminum or steel and also medical application. Operating at wavelengths between 900 nm and 1100 nm, these systems are mainly used in cutting and welding, but the technology can also be adapted to other wavelength ranges, such as 793 nm and 1530 nm. Around 1.5 μm the diodes are already successfully used for resonant pumping of Erbium lasers.[1] Furthermore, the fully integrated electronic concept allows addressing further applications, as it is capable of very short μs pulses up to cw mode operation by simple software commands.

  2. Prototype Test Results for the Single Photon Detection SLR2000 Satellite Laser Ranging System

    NASA Technical Reports Server (NTRS)

    Zagwodzki, Thomas W.; McGarry, Jan F.; Degnan, John J.; Cheek, Jack W.; Dunn, Peter J.; Patterson, Don; Donovan, Howard

    2004-01-01

    NASA's aging Satellite Laser Ranging (SLR) network is scheduled to be replaced over the next few years with a fully automated single photon detection system. A prototype of this new system, called SLR2000, is currently undergoing field trials at the Goddard Space Flight Center in Greenbelt, Maryland to evaluate photon counting techniques and determine system hardware, software, and control algorithm performance levels and limitations. Newly developed diode pumped microchip lasers and quadrant microchannel plate-based photomultiplier tubes have enabled the development of this high repetition rate single photon detection SLR system. The SLR2000 receiver threshold is set at the single photoelectron (pe) level but tracks satellites with an average signal level typically much less than 1 pe. The 2 kHz laser fire rate aids in satellite acquisition and tracking and will enable closed loop tracking by accumulating single photon count statistics in a quadrant detector and using this information to correct for pointing errors. Laser transmitter beamwidths of 10 arcseconds (FWHM) or less are currently being used to maintain an adequate signal level for tracking while the receiver field of view (FOV) has been opened to 40 arcseconds to accommodate point ahead/look behind angular offsets. In the near future, the laser transmitter point ahead will be controlled by a pair of Risley prisms. This will allow the telescope to point behind and enable closure of the receiver FOV to roughly match the transmitter beam divergence. Bandpass filters (BPF) are removed for night tracking operations while 0.2 nm or 1 nm filters are used during daylight operation. Both day and night laser tracking of Low Earth Orbit (LEO) satellites has been achieved with a laser transmitter energy of only 65 microjoules per pulse. Satellite tracking is presently limited to LEO satellites until the brassboard laser transmitter can be upgraded or replaced. Simultaneous tracks have also been observed with NASA s

  3. Assessing the Financial Viability of Academic Programmes

    ERIC Educational Resources Information Center

    Swift, Lynette

    2012-01-01

    This paper reviews and examines approaches to determining the financial viability of academic programmes as a critical component of assessing a programme's overall sustainability. Key to assessing the financial viability of a programme is understanding the teaching activities required to deliver the programme and the cost of those activities. A…

  4. Experiments with the Viability of Chicken Eggs

    ERIC Educational Resources Information Center

    Garigliano, Leonard J.

    1975-01-01

    Presents the results of an experiment designed to test two hypotheses: (1) a delay of two weeks at room temperature will have no effect on the viability of fertile chicken eggs and (2) refrigeration will have no effect on the viability of fertile chicken eggs. Experimenters were the author and two ninth-grade students. (PEB)

  5. Multiple-input multiple-output synthetic aperture ladar system for wide-range swath with high azimuth resolution.

    PubMed

    Tang, Yu; Qin, Bao; Yan, Yun; Xing, Mengdao

    2016-02-20

    For the trade-off between the high azimuth resolution and the wide-range swath in the single-input single-output synthetic aperture ladar (SAL) system, the range swath of the SAL system is restricted to a narrow range, this paper proposes a multiple-input multiple-output (MIMO) synthetic aperture ladar system. The MIMO system adopts a low pulse repetition frequency (PRF) to avoid a range ambiguity for the wide-range swath and in azimuth adopts the multi-channel method to achieve azimuth high resolution from the unambiguous azimuth wide-spectrum signal, processed through adaptive digital beam-forming technology. Simulations and analytical results are presented.

  6. A pan-African medium-range ensemble flood forecast system

    NASA Astrophysics Data System (ADS)

    Thiemig, Vera; Bisselink, Bernard; Pappenberger, Florian; Thielen, Jutta

    2015-04-01

    AFFS showed limitations for small-scale and short duration flood events. Also the forecasts showed on average a good reliability, and the CRPSS helped identifying regions to focus on for future improvements. The case study for the flood event in March 2003 in the Sabi Basin (Zimbabwe and Mozambique) illustrated the good performance of AFFS in forecasting timing and severity of the floods, gave an example of the clear and concise output products, and showed that the system is capable of producing flood warnings even in ungauged river basins. Hence, from a technical perspective, AFFS shows a good prospective as an operational system, as it has demonstrated its significant potential to contribute to the reduction of flood-related losses in Africa by providing national and international aid organizations timely with medium-range flood forecast information. However, issues related to the practical implication will still need to be investigated.

  7. Heifer development systems: a comparison of grazing winter range or corn residue.

    PubMed

    Larson, D M; Cupp, A S; Funston, R N

    2011-08-01

    Two experiments at 2 Nebraska locations evaluated effects of heifer development system on growth and pregnancy rate. In Exp. 1, heifers (n=270, BW=225 ± 2 kg) grazed winter Sandhills range (WR) or west central Nebraska corn residue (CR) with a supplement (0.45 kg/animal; 31% CP; 80 mg·animal(-1)·d(-1) of monensin). In Exp. 2, heifers (n=180, BW = 262 ± 3 kg) grazed eastern Nebraska WR or CR with a supplement (0.45 to 0.90 kg/d; 31% CP; 80 to 160 mg·animal(-1)·d(-1) of monensin). The CR heifers tended to have less (P=0.10) ADG compared with WR heifers before breeding in Exp. 1; however, prebreeding ADG was similar (P=0.77) in Exp. 2. Prebreeding BW, percentage of mature BW at breeding, and pregnancy determination BW were similar (P ≥ 0.14) for CR and WR in both experiments. Percentage of heifers pubertal at breeding, AI conception, and AI pregnancy rate (Exp. 2) and final pregnancy rate in both experiments were also similar (P ≥ 0.27) for CR and WR heifers. Precalving BW, percentage of calves born in the first 21 d, calf birth date, calf birth BW, and dystocia score were all similar (P ≥ 0.21) for CR and WR heifers in both experiments. Cow BW at weaning, calf weaning BW, adjusted 205-d calf BW, and second season pregnancy rates were not affected (P ≥ 0.16) by treatment. Heifer development system did not affect (P ≥ 0.56) the cost of producing 1 pregnant heifer in Exp. 1 or 2. Development on CR may reduce ADG before breeding, but did not affect pregnancy rate. Heifer development using CR or WR postweaning resulted in similar reproductive performance and development cost.

  8. Study report recommendations for the next generation Range Safety System (RSS) Integrated Receiver/Decoder (IRD)

    NASA Technical Reports Server (NTRS)

    Crosby, Robert H.

    1992-01-01

    The Integrated Receiver/Decoder (IRD) currently used on the Space Shuttle was designed in the 1980 and prior time frame. Over the past 12 years, several parts have become obsolete or difficult to obtain. As directed by the Marshall Space Flight Center, a primary objective is to investigate updating the IRD design using the latest technology subsystems. To take advantage of experience with the current designs, an analysis of failures and a review of discrepancy reports, material review board actions, scrap, etc. are given. A recommended new design designated as the Advanced Receiver/Decoder (ARD) is presented. This design uses the latest technology components to simplify circuits, improve performance, reduce size and cost, and improve reliability. A self-test command is recommended that can improve and simplify operational procedures. Here, the new design is contrasted with the old. Possible simplification of the total Range Safety System is discussed, as is a single-step crypto technique that can improve and simplify operational procedures.

  9. Evidence of Long Range Dependence and Self-similarity in Urban Traffic Systems

    SciTech Connect

    Thakur, Gautam S; Helmy, Ahmed; Hui, Pan

    2015-01-01

    Transportation simulation technologies should accurately model traffic demand, distribution, and assignment parame- ters for urban environment simulation. These three param- eters significantly impact transportation engineering bench- mark process, are also critical in realizing realistic traffic modeling situations. In this paper, we model and charac- terize traffic density distribution of thousands of locations around the world. The traffic densities are generated from millions of images collected over several years and processed using computer vision techniques. The resulting traffic den- sity distribution time series are then analyzed. It is found using the goodness-of-fit test that the traffic density dis- tributions follows heavy-tail models such as Log-gamma, Log-logistic, and Weibull in over 90% of analyzed locations. Moreover, a heavy-tail gives rise to long-range dependence and self-similarity, which we studied by estimating the Hurst exponent (H). Our analysis based on seven different Hurst estimators strongly indicate that the traffic distribution pat- terns are stochastically self-similar (0.5 H 1.0). We believe this is an important finding that will influence the design and development of the next generation traffic simu- lation techniques and also aid in accurately modeling traffic engineering of urban systems. In addition, it shall provide a much needed input for the development of smart cities.

  10. Feasibility of Close-Range Photogrammetric Models for Geographic Information System

    SciTech Connect

    Zhou, Luke; /Rice U.

    2011-06-22

    The objective of this project was to determine the feasibility of using close-range architectural photogrammetry as an alternative three dimensional modeling technique in order to place the digital models in a geographic information system (GIS) at SLAC. With the available equipment and Australis photogrammetry software, the creation of full and accurate models of an example building, Building 281 on SLAC campus, was attempted. After conducting several equipment tests to determine the precision achievable, a complete photogrammetric survey was attempted. The dimensions of the resulting models were then compared against the true dimensions of the building. A complete building model was not evidenced to be obtainable using the current equipment and software. This failure was likely attributable to the limits of the software rather than the precision of the physical equipment. However, partial models of the building were shown to be accurate and determined to still be usable in a GIS. With further development of the photogrammetric software and survey procedure, the desired generation of a complete three dimensional model is likely still feasible.

  11. Multilateration with the wide-angle airborne laser ranging system: positioning precision and atmospheric effects.

    PubMed

    Bock, O

    1999-05-20

    Numerical simulations based on previously validated models for the wide-angle airborne laser ranging system are used here for assessing the precision in coordinate estimates of ground-based cube-corner retroreflectors (CCR's). It is shown that the precision can be optimized to first order as a function of instrument performance, number of laser shots (LS's), and network size. Laser beam divergence, aircraft altitude, and CCR density are only second-order parameters, provided that the number of echoes per LS is greater than 20. Thus precision in the vertical is approximately 1 mm, with a signal-to-noise ratio of 50 at nadir, a 10-km altitude, a 20 degrees beam divergence, and approximately 5 x 10(3) measurements. Scintillation and fair-weather cumulus clouds usually have negligible influence on the estimates. Laser biases and path delay are compensated for by adjustment of aircraft offsets. The predominant atmospheric effect is with mesoscale nonuniform horizontal temperature gradients, which might lead to biases near 0.5 mm.

  12. Critique of the mid-range energy forecasting, system oil and gas supply models

    SciTech Connect

    Patton, W.P.

    1980-10-01

    The Mid-Range Energy Forecasting System (MEFS) is a model used by the Department of Energy to forecast domestic production, consumption and price for conventional energy sources on a regional basis over a period of 5 to 15 years. Among the energy sources included in the model are oil, gas and other petroleum fuels, coal, uranium, and electricity. Final consumption of alternative energy sources is broken into end-use categories, such as residential, commercial and industrial uses. Regional prices for all energy sources are calculated by iteratively equating domestic supply and demand. The purpose of this paper is to assess the ability of the Oil and Gas Supply Submodels of MEFS to reliably and accurately project oil and gas supply curves, which are used in the integrating model, along with fuel demand curves to estimate market price. The reliability and accuracy of the oil and gas model cannot be judged by comparing its predictions against actual observations because those observations have not yet occurred. The reliability and reasonableness of the oil and gas supply model can be judged, however, by analyzing how well its assumptions and predictions correspond to accepted economic principles. This is the approach taken in this critique. The remainder of this paper describes the general structure of the oil and gas supply model and how it functions to project the quantity of oil and gas forthcoming at given prices in a particular year, then discusses the economic soundness of the model, and finally suggests model changes to improve its performance.

  13. Modeling the Colorado Front Range Flood of 2013 with Coupled WRF and WRF-Hydro System

    NASA Astrophysics Data System (ADS)

    Unal, E.; Ramirez, J. A.

    2015-12-01

    Abstract. Flash floods are one of the most damaging natural disasters producing large socio-economic losses. Projected impacts of climate change include increases in the magnitude and the frequency of flash floods all around the world. Therefore, it is important to understand the physical processes of flash flooding to enhance our capacity for prediction, prevention, risk management, and recovery. However, understanding these processes is ambitious because of small spatial scale and sudden nature of flash floods, interactions with complex topography and land use, difficulty in defining initial soil moisture conditions, non-linearity of catchment response, and high space-time variability of storm characteristics. Thus, detailed regional case studies are needed, especially with respect to the interactions between the land surface and the atmosphere. One such flash flood event occurred recently in the Front Range of the Rocky Mountains of Colorado during September 9-15, 2013 causing 10 fatalities and $3B cost in damages. An unexpected persistent and moist weather pattern located over the mountains and produced seven-day extreme rainfall fed by moisture input from the Gulf of Mexico. We used a coupled WRF-WRF-Hydro modeling system to simulate this event for better understanding of the physical process and of the sensitivity of the hydrologic response to storm characteristics, initial soil moisture conditions, and watershed characteristics.

  14. Testing a dual-fluorescence assay to monitor the viability of filamentous cyanobacteria.

    PubMed

    Johnson, Tylor J; Hildreth, Michael B; Gu, Liping; Zhou, Ruanbao; Gibbons, William R

    2015-06-01

    Filamentous cyanobacteria are currently being engineered to produce long-chain organic compounds, including 3rd generation biofuels. Because of their filamentous morphology, standard methods to quantify viability (e.g., plate counts) are not possible. This study investigated a dual-fluorescence assay based upon the LIVE/DEAD® BacLight™ Bacterial Viability Kit to quantify the percent viability of filamentous cyanobacteria using a microplate reader in a high throughput 96-well plate format. The manufacturer's protocol calls for an optical density normalization step to equalize the numbers of viable and non-viable cells used to generate calibration curves. Unfortunately, the isopropanol treatment used to generate non-viable cells released a blue pigment that altered absorbance readings of the non-viable cell solution, resulting in an inaccurate calibration curve. Thus we omitted this optical density normalization step, and carefully divided cell cultures into two equal fractions before the isopropanol treatment. While the resulting calibration curves had relatively high correlation coefficients, their use in various experiments resulted in viability estimates ranging from below 0% to far above 100%. We traced this to the apparent inaccuracy of the propidium iodide (PI) dye that was to stain only non-viable cells. Through further analysis via microplate reader, as well as confocal and wide-field epi-fluorescence microscopy, we observed non-specific binding of PI in viable filamentous cyanobacteria. While PI will not work for filamentous cyanobacteria, it is possible that other fluorochrome dyes could be used to selectively stain non-viable cells. This will be essential in future studies for screening mutants and optimizing photobioreactor system performance for filamentous cyanobacteria.

  15. USE OF POPULATION VIABILITY ANALYSIS AND RESERVE SELECTION ALGORITHMS IN REGIONAL CONSERVATION PLANS

    EPA Science Inventory

    Current reserve selection algorithms have difficulty evaluating connectivity and other factors
    necessary to conserve wide-ranging species in developing landscapes. Conversely, population viability analyses may incorporate detailed demographic data but often lack sufficient spa...

  16. New Satellite Laser Ranging TRF and EOP Series for Mass Transport Studies in the Earth System

    NASA Astrophysics Data System (ADS)

    Pavlis, E. C.

    2001-12-01

    The new millennium has started on the right note for geodesy. We finally see a series of gravity mapping missions materialize. What now becomes important is that well-established geodetic techniques rise to the challenge of validating and complementing the data these new missions will deliver. An area where this is likely to be important is the temporal variations in the zonal gravitational field and its very low degree and order components in general. Satellite laser ranging (SLR) has for a long time monitored the continuous redistribution of mass within the Earth system through concomitant changes in the Stokes' coefficients of the terrestrial gravity field. Secular changes in J2 due to post-glacial relaxation have been observed since many years and similar changes in J3, J4 J5, etc. are attributed to changes in the ice sheets of Greenland and Antarctica. Seasonal changes in these coefficients have also been closely correlated with mass transfer in the atmosphere and oceans. JCET's latest analysis of the 1993-present SLR data set from LAGEOS and LAGEOS 2 data for the IERS (International Earth Rotation Service) Terrestrial Reference Frame (ITRF) development, includes the weekly monitoring of such compound changes in the low degree and order harmonics. This latest solution (2001) incorporates several important changes in the modeling of SLR data with resulting improvements in the geophysical products. Along with the static parameters of the TRF we have determined a time series of variations of its origin with respect to the center of mass of the Earth system (geocenter). These estimates provide a measure of the total motion due to all sources of mass transport within the Earth system and can be used to either complement the estimates from the future missions or to validate them through comparisons with their estimates for the same quantities. The data were reduced using NASA Goddard's GEODYN/SOLVE II software, resulting to a final RMS error of ~8 mm - close to the

  17. Continuous wave synthetic low-coherence wind sensing Lidar: motionless measurement system with subsequent numerical range scanning.

    PubMed

    Brinkmeyer, Ernst; Waterholter, Thomas

    2013-01-28

    A continuous wave (CW) Lidar system for detection of scattering from atmospheric aerosol particles is presented which is useful in particular for remote sensing of wind velocities. It is based on a low-coherence interferometric setup powered by a synthetic broadband laser source with Gaussian power density spectrum. The laser bandwidth is electronically adjustable and determines the spatial resolution which is independent of range. The Lidar system has no moving parts. The location to be resolved can be shifted numerically after the measurement meaning that a single measurement already contains the full range information. The features of constant resolution and numerical range scanning are in sharp contrast to ordinary CW Lidar systems.

  18. Dynamic range compression in the honey bee auditory system toward waggle dance sounds.

    PubMed

    Tsujiuchi, Seiya; Sivan-Loukianova, Elena; Eberl, Daniel F; Kitagawa, Yasuo; Kadowaki, Tatsuhiko

    2007-02-21

    Honey bee foragers use a "waggle dance" to inform nestmates about direction and distance to locations of attractive food. The sound and air flows generated by dancer's wing and abdominal vibrations have been implicated as important cues, but the decoding mechanisms for these dance messages are poorly understood. To understand the neural mechanisms of honey bee dance communication, we analyzed the anatomy of antenna and Johnston's organ (JO) in the pedicel of the antenna, as well as the mechanical and neural response characteristics of antenna and JO to acoustic stimuli, respectively. The honey bee JO consists of about 300-320 scolopidia connected with about 48 cuticular "knobs" around the circumference of the pedicel. Each scolopidium contains bipolar sensory neurons with both type I and II cilia. The mechanical sensitivities of the antennal flagellum are specifically high in response to low but not high intensity stimuli of 265-350 Hz frequencies. The structural characteristics of antenna but not JO neurons seem to be responsible for the non-linear responses of the flagellum in contrast to mosquito and fruit fly. The honey bee flagellum is a sensitive movement detector responding to 20 nm tip displacement, which is comparable to female mosquito. Furthermore, the JO neurons have the ability to preserve both frequency and temporal information of acoustic stimuli including the "waggle dance" sound. Intriguingly, the response of JO neurons was found to be age-dependent, demonstrating that the dance communication is only possible between aged foragers. These results suggest that the matured honey bee antennae and JO neurons are best tuned to detect 250-300 Hz sound generated during "waggle dance" from the distance in a dark hive, and that sufficient responses of the JO neurons are obtained by reducing the mechanical sensitivity of the flagellum in a near-field of dancer. This nonlinear effect brings about dynamic range compression in the honey bee auditory system.

  19. The integrated platform of controlling and digital video processing for underwater range-gated laser imaging system

    NASA Astrophysics Data System (ADS)

    Shi, Yan; Qiu, Su; Jin, Wei-qi; Yu, Bing; Li, Li; Tian, Dong-kang

    2015-04-01

    Laser range-gated imaging is one of the effective techniques of underwater optical imaging. It could make the viewing distance up to 4 to 7 times with the video image processing technology. Accordingly, the control and image processing technologies come to be the key technologies for the underwater laser range-gated imaging system. In this article, the integrated platform of controlling and digital video processing for the underwater range-gated laser imaging system based on FPGA has been introduced. It accomplishes both the communication for remote control system as the role of lower computer and the task of high-speed images grabbing and video enhance processing as the role of high-speed image processing platform. The host computer can send commands composed to the FPGA, vectoring the underwater range-gated laser imaging system to executive operation.

  20. Evaluation of some wide dynamic range readout systems for photoelectric integrating spectrometers

    NASA Technical Reports Server (NTRS)

    Franklin, M. L.; Gordon, W. A.

    1971-01-01

    Five types of electronic circuits commonly used for readout of currents from photomultiplier tubes were evaluated. This evaluation was conducted to define the experimental limits of achieving the widest possible dynamic range of light detection and concentration measurements in spectrochemical analysis. The circuits evaluated included the photon-counting technique and four dc circuits. These circuits displayed a dynamic range from 3 to about 4.5 decades within a repeatability criterion of 1 percent, or better. The maximum dynamic range allowed by the photomultiplier tube in this application was estimated to be about 6 decades.

  1. Echo detection and target-ranging neurons in the auditory system of the bat Eptesicus fuscus.

    PubMed

    Feng, A S; Simmons, J A; Kick, S A

    1978-11-10

    Some of the neurons in the nucleus intercollicularis and auditory cortex of the echolocating bat Eptesicus fuscus respond selectively to sonar echoes occurring with specific echo delays or pulse-echo intervals. They do not respond for a wide range of other types of sounds or for sonar echoes at longer or shorter pulse-echo intervals; they may, therefore, be specialized for detection and ranging of sonar targets.

  2. Coherent systems in the terahertz frequency range: Elements, operation, and examples

    NASA Technical Reports Server (NTRS)

    Goldsmith, Paul F.

    1992-01-01

    The topics are presented in viewgraph form and include the following: terahertz coherent systems applications; a brief overview of selected components; radiometry and spectroscopy--astronomy; radiometry--aircraft all weather landing system; radiometry--atmospheric remote sensing; plasma diagnostics; communications; radar systems; and materials measurement and manufacturing process control.

  3. Effective Learning in Science: The Use of Personal Response Systems with a Wide Range of Audiences

    ERIC Educational Resources Information Center

    Moss, Karen; Crowley, Mark

    2011-01-01

    This paper describes the flexibility of Personal Response Systems (PRSs), (also known as "clickers" or electronic voting systems (EVS)), as part of strategies to support students' learning in science. Whilst variants of this technology began to appear 12 years ago, there is now a steadily increasing adoption of these systems within higher…

  4. Lithospheric fault and kinematic decoupling of the Apennines system across the Pollino range

    NASA Astrophysics Data System (ADS)

    Chiarabba, Claudio; Agostinetti, Nicola Piana; Bianchi, Irene

    2016-04-01

    A persistent seismic gap is hypothesized in the Pollino area (southern Italy), at the boundary between the Apennines and the Calabrian arc. Presently, seismic swarms are active in the gap area, creating concerns for possible future large earthquakes. In this study, we model the deep Earth structure across the Pollino range to give new insights on the kinematics and tectonics of this enigmatic area. Migrated receiver function profiles show a subvertical lithospheric discontinuity, delineated by an abrupt change in Moho depth and mantle fabrics across the range. The lithospheric-scale discontinuity bounds the area of earthquake swarm activity and likely decouples the delamination-related extension of the Apennines from the extensional collapse of the Calabrian fore arc. This large-scale discontinuity implies that the normal faults are segmented across the range, limiting the lateral extent of faults where future earthquakes might occur.

  5. Crossover of the roughness exponent for interface growth in systems with long-range interactions due to lattice distortion

    NASA Astrophysics Data System (ADS)

    Nishino, Masamichi; Nakada, Taro; Enachescu, Cristian; Boukheddaden, Kamel; Miyashita, Seiji

    2013-09-01

    We study domain wall propagation in systems with long-range interactions caused by lattice distortion. When the local bistable states of the molecular unit have different sizes, e.g., high-spin and low-spin states in spin-crossover systems, the elastic distortion causes an effective long-range interaction. In switching processes between the ordered states in such systems, there exist two degrees of freedom for the domain wall, that is, one with respect to lattice structure and the other to a bistable spin (electronic) state. The interface width of the lattice domain wall is proportional to the system size, which reflects the macroscopic structure due to the long-range interaction, while the interface width of the spin state shows different characteristics depending on the relative time scales of dynamics of the spin state and the lattice. When the change of the spin state is relatively fast and the lattice relaxation is insufficient, the roughness exponent α is 1/2, which has been commonly found in growth models of short-range interaction systems in two dimensions. In contrast, when the lattice relaxes sufficiently, α of the spin interface is the same as that of the lattice interface, i.e., α=1. We analyze the pressure field of the systems and find that the equilibration of the field via the long-range interaction plays a key role in the mechanism of the crossover of α between 1/2 and 1.

  6. Receiver Design, Performance Analysis, and Evaluation for Space-Borne Laser Altimeters and Space-to-Space Laser Ranging Systems

    NASA Technical Reports Server (NTRS)

    Davidson, Frederic M.; Sun, Xiaoli; Field, Christopher T.

    1996-01-01

    This progress report consists of two separate reports. The first one describes our work on the use of variable gain amplifiers to increase the receiver dynamic range of space borne laser altimeters such as NASA's Geoscience Laser Altimeter Systems (GLAS). The requirement of the receiver dynamic range was first calculated. A breadboard variable gain amplifier circuit was made and the performance was fully characterized. The circuit will also be tested in flight on board the Shuttle Laser Altimeter (SLA-02) next year. The second report describes our research on the master clock oscillator frequency calibration for space borne laser altimeter systems using global positioning system (GPS) receivers.

  7. The development of an information system master plan for the Pacific Missile Range Facility, Barking Sands, Hawaii

    NASA Astrophysics Data System (ADS)

    Apollo, Rolando A.; Bennett, Paul D.

    1992-03-01

    This thesis provides a general description of the communication facilities and systems currently used by the Pacific Missile Range Facility (PMRF). The system interface requirements to support current range operations are identified and a description of current communications system shortfalls is provided along with recommendations for short-term improvements. A vision of the future is also provided. It suggests that PMRF adopt a coordinated, integrated, and centralized approach to range communications. Current and future communications system technologies such as digital communications, applicability of different transmission media, and application of the Integrated Services Digital Network (ISDN) are mentioned as avenues for implementing a fully integrated data, voice, and video real-time information network that will support future PMRF users' requirements.

  8. Performance Evaluation of an Expanded Range XIPS Ion Thruster System for NASA Science Missions

    NASA Technical Reports Server (NTRS)

    Oh, David Y.; Goebel, Dan M.

    2006-01-01

    This paper examines the benefit that a solar electric propulsion (SEP) system based on the 5 kW Xenon Ion Propulsion System (XIPS) could have for NASA's Discovery class deep space missions. The relative cost and performance of the commercial heritage XIPS system is compared to NSTAR ion thruster based systems on three Discovery class reference missions: 1) a Near Earth Asteroid Sample Return, 2) a Comet Rendezvous and 3) a Main Belt Asteroid Rendezvous. It is found that systems utilizing a single operating XIPS thruster provides significant performance advantages over a single operating NSTAR thruster. In fact, XIPS performs as well as systems utilizing two operating NSTAR thrusters, and still costs less than the NSTAR system with a single operating thruster. This makes XIPS based SEP a competitive and attractive candidate for Discovery class science missions.

  9. Design of a multi-sensor sonar system for indoor range measurement as a navigational aid for the blind.

    PubMed

    Choudhury, Maroof H; Barreto, Armando

    2003-01-01

    This paper reports the methodology for the design of a sonar-based ranging and guidance system. The intended application of the system is to help a blind person avoid obstacles as he/she navigates his/her environment. Six sonar transceivers are arranged radially on a headgear worn by the user. The transceivers detect discrete range data at discrete-time sampling instances. A panoramic map of the environment is generated from the discrete-space sensory data. The paper emphasizes the challenges faced during the measurement of omnidirectional ranging information in indoor environments. Situations have been identified where erroneous range readings are generated due to channel cross talk caused by echo bouncing off multiple surfaces. Several sonar control and measurement schemes were developed and tested to avoid these situations. The results and performance of these different control schemes are compared in this paper. A microcontroller-based system commands the sonar ping sequences, acquires the echo return times and computes the ranges. The set of range data is transmitted to a PC, which utilizes the information to build a spatialized audio map of the surrounding obstacles. The hardware and software layout for the system are described in this paper.

  10. Comparison of hen preference for nesting substrate material, and performance in a free range production system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This project consisted of 200 Hy-Line Brown hens and was conducted utilizing the brood-grow-lay range huts at the North Carolina Department of Agriculture and Consumer Services’ Piedmont Research Station. Fifty hens were placed in each pen/paddock providing 1338 cm2/hen of floor space in the hut an...

  11. Effects of conidial densities and spray volume of Metarhizium anisopliae and Beauveria bassiana fungal suspensions on conidial viability, droplet size and deposition coverage in bioassay using a novel bioassay spray system

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were conducted to study the conidial viability during bioassay spray with different suspensions of Metarhizium anisopliae ATCC 62176 and Beauveria bassiana NI8, and to investigate the effects of conidial density and spray volume on the distribution of droplet size and deposit coverage us...

  12. Shuttle communication systems compatibility and performance tests. [transponder, range error, and power amplifier problems

    NASA Technical Reports Server (NTRS)

    Bromley, L. K.; Travis, A. D.

    1980-01-01

    The compatibility and performance of the Shuttle communications system must be certified prior to operational missions. For this purpose, NASA has established the Electronics Systems Test Laboratory (ESTL) at the Johnson Space Center. This paper discusses the Shuttle communications system compatibility and performance testing being performed in the ESTL. The ESTL system verification test philosophy, including capabilities, procedures, and unique testing equipment are summarized. Summaries of the significant results of compatibility and performance tests of the Orbiter/Space-flight Tracking and Data Network, Orbiter/Air Force Remote Tracking Station, Orbiter/Tracking and Data Relay Satellite System and Orbiter/Shuttle Launch Support System interfaces are presented. The ESTL's unique ability to locate potential communication problems and participate in the resolution of these problems are discussed in detail.

  13. Assessment of tissue viability by polarization spectroscopy

    NASA Astrophysics Data System (ADS)

    Nilsson, G.; Anderson, C.; Henricson, J.; Leahy, M.; O'Doherty, J.; Sjöberg, F.

    2008-09-01

    A new and versatile method for tissue viability imaging based on polarization spectroscopy of blood in superficial tissue structures such as the skin is presented in this paper. Linearly polarized light in the visible wavelength region is partly reflected directly by the skin surface and partly diffusely backscattered from the dermal tissue matrix. Most of the directly reflected light preserves its polarization state while the light returning from the deeper tissue layers is depolarized. By the use of a polarization filter positioned in front of a sensitive CCD-array, the light directly reflected from the tissue surface is blocked, while the depolarized light returning from the deeper tissue layers reaches the detector array. By separating the colour planes of the detected image, spectroscopic information about the amount of red blood cells (RBCs) in the microvascular network of the tissue under investigation can be derived. A theory that utilizes the differences in light absorption of RBCs and bloodless tissue in the red and green wavelength region forms the basis of an algorithm for displaying a colour coded map of the RBC distribution in a tissue. Using a fluid model, a linear relationship (cc. = 0.99) between RBC concentration and the output signal was demonstrated within the physiological range 0-4%. In-vivo evaluation using transepidermal application of acetylcholine by the way of iontophoresis displayed the heterogeneity pattern of the vasodilatation produced by the vasoactive agent. Applications of this novel technology are likely to be found in drug and skin care product development as well as in the assessment of skin irritation and tissue repair processes and even ultimately in a clinic case situation.

  14. Blade tip clearance measurement of the turbine engines based on a multi-mode fiber coupled laser ranging system.

    PubMed

    Guo, Haotian; Duan, Fajie; Wu, Guoxiu; Zhang, Jilong

    2014-11-01

    The blade tip clearance is a parameter of great importance to guarantee the efficiency and safety of the turbine engines. In this article, a laser ranging system designed for blade tip clearance measurement is presented. Multi-mode fiber is utilized for optical transmission to guarantee that enough optical power is received by the sensor probe. The model of the tiny sensor probe is presented. The error brought by the optical path difference of different modes of the fiber is estimated and the length of the fiber is limited to reduce this error. The measurement range in which the optical power received by the probe remains essentially unchanged is analyzed. Calibration experiments and dynamic experiments are conducted. The results of the calibration experiments indicate that the resolution of the system is about 0.02 mm and the range of the system is about 9 mm.

  15. Blade tip clearance measurement of the turbine engines based on a multi-mode fiber coupled laser ranging system

    SciTech Connect

    Guo, Haotian; Duan, Fajie; Wu, Guoxiu; Zhang, Jilong

    2014-11-15

    The blade tip clearance is a parameter of great importance to guarantee the efficiency and safety of the turbine engines. In this article, a laser ranging system designed for blade tip clearance measurement is presented. Multi-mode fiber is utilized for optical transmission to guarantee that enough optical power is received by the sensor probe. The model of the tiny sensor probe is presented. The error brought by the optical path difference of different modes of the fiber is estimated and the length of the fiber is limited to reduce this error. The measurement range in which the optical power received by the probe remains essentially unchanged is analyzed. Calibration experiments and dynamic experiments are conducted. The results of the calibration experiments indicate that the resolution of the system is about 0.02 mm and the range of the system is about 9 mm.

  16. Continuous wave synthetic low-coherence wind sensing Lidar: motionless measurement system with subsequent numerical range scanning.

    PubMed

    Brinkmeyer, Ernst; Waterholter, Thomas

    2013-01-28

    A continuous wave (CW) Lidar system for detection of scattering from atmospheric aerosol particles is presented which is useful in particular for remote sensing of wind velocities. It is based on a low-coherence interferometric setup powered by a synthetic broadband laser source with Gaussian power density spectrum. The laser bandwidth is electronically adjustable and determines the spatial resolution which is independent of range. The Lidar system has no moving parts. The location to be resolved can be shifted numerically after the measurement meaning that a single measurement already contains the full range information. The features of constant resolution and numerical range scanning are in sharp contrast to ordinary CW Lidar systems. PMID:23389172

  17. Tauroursodeoxycholic acid improves viability of artificial RBCs.

    PubMed

    Hong, Shin Hee; Yoon, Kang Jun; Lim, Key-Hwan; Um, Yun Jung; Cho, Jin Gu; Jo, Young Joon; Park, Sang Gyu

    2016-09-30

    Tauroursodeoxycholic acid (TUDCA) is known to prevent apoptosis through the Bax pathway and to promote neovascularization by enhancing the mobilization of stem cells, their differentiation. This study was performed to investigate the effect of TUDCA on erythropoiesis in hematopoietic stem cells (HSCs). Since erythropoiesis of CD34(+) HSCs is divided into four phases, the total cell number, viable cell number, cell viability, cell morphology, and expressed erythroid markers in each phase were examined. The number of viable control cells and their viability did not differ from those of the TUDCA-treated cells in phase I and II. However, TUDCA increased cell viability compared to the control in phases III and IV. Cell distribution differed that the immature erythroid cell number was higher for the TUDCA-treated cells than for the control cells until phase III, but all developed into RBCs in the last. The final RBC number and viability was significantly higher in TUDCA-treated cells compared to the control cells. Taken together, we suggest that TUDCA addition to cell cultures for artificial RBC production could be used as a new protocol for improving the viability of RBCs. PMID:27596970

  18. Tauroursodeoxycholic acid improves viability of artificial RBCs.

    PubMed

    Hong, Shin Hee; Yoon, Kang Jun; Lim, Key-Hwan; Um, Yun Jung; Cho, Jin Gu; Jo, Young Joon; Park, Sang Gyu

    2016-09-30

    Tauroursodeoxycholic acid (TUDCA) is known to prevent apoptosis through the Bax pathway and to promote neovascularization by enhancing the mobilization of stem cells, their differentiation. This study was performed to investigate the effect of TUDCA on erythropoiesis in hematopoietic stem cells (HSCs). Since erythropoiesis of CD34(+) HSCs is divided into four phases, the total cell number, viable cell number, cell viability, cell morphology, and expressed erythroid markers in each phase were examined. The number of viable control cells and their viability did not differ from those of the TUDCA-treated cells in phase I and II. However, TUDCA increased cell viability compared to the control in phases III and IV. Cell distribution differed that the immature erythroid cell number was higher for the TUDCA-treated cells than for the control cells until phase III, but all developed into RBCs in the last. The final RBC number and viability was significantly higher in TUDCA-treated cells compared to the control cells. Taken together, we suggest that TUDCA addition to cell cultures for artificial RBC production could be used as a new protocol for improving the viability of RBCs.

  19. Engineered cerium oxide nanoparticles: Effects on bacterial growth and viability

    SciTech Connect

    Pelletier, Dale A; Suresh, Anil K; Holton, Gregory A; McKeown, Catherine K; Wang, Wei; Gu, Baohua; Mortensen, Ninell P; Allison, David P; Joy, David Charles; Allison, Martin R; Brown, Steven D; Phelps, Tommy Joe; Doktycz, Mitchel John

    2010-01-01

    Interest in engineered nanostructures has risen in recent years due to their use in energy conservation strategies and biomedicine. To ensure prudent development and use of nanomaterials, the fate and effects of such engineered structures on the environment should be understood. Interactions of nanomaterials with environmental microorganisms are inevitable, but the general consequences of such interactions remain unclear. Further, standardized methods for assessing such interactions are lacking. Therefore, we have initiated a multianalytical approach to understand the interactions of synthesized nanoparticles with bacterial systems. These efforts are focused initially on cerium oxide nanoparticles and model bacteria in order to evaluate characterization procedures and the possible fate of such materials in the environment. In this study the effects of cerium oxide nanoparticles on the growth and viability of Gram-negative Escherichia coli and Shewanella oneidensis, a metal-reducing bacteria, and Gram-positive Bacillus subtilis were examined relative to particle size, growth media, pH, and dosage. A hydrothermal based synthesis procedure was used to prepare cerium oxide nanoparticles of defined sizes in order to eliminate complications originating from the use of organic solvents and surfactants. Bactericidal effects were determined by minimum inhibitory concentration, colony forming units, disc diffusion tests and Live/Dead assays. In growth inhibition experiments involving E. coli and B. subtilis, a clear strain and size-dependent inhibition was observed. S. oneidensis appeared to be unaffected by the cerium oxide nanoparticles. Transmission electron microscopy along with microarray-based transcriptional profiling have been used to understand the response mechanism of the bacteria. The use of multiple analytical approaches adds confidence to toxicity assessments while the use of different bacterial systems highlights the potential wide-ranging effects of

  20. COST IMPACT OF ROD CONSOLIDATION ON THE VIABILITY ASSESSMENT DESIGN

    SciTech Connect

    D. Lancaster

    1999-03-29

    The cost impact to the Civilian Radioactive Waste Management System of using rod consolidation is evaluated. Previous work has demonstrated that the fuel rods of two assemblies can be packed into a canister that can fit into the same size space as that used to store a single assembly. The remaining fuel assembly hardware can be compacted into the same size canisters with a ratio of 1 hardware canister per each 6 to 12 assemblies. Transportation casks of the same size as currently available can load twice the number of assemblies by placing the compacted assemblies in the slots currently designed for a single assembly. Waste packages similarly could contain twice the number of assemblies; however, thermal constraints would require considering either a low burnup or cooling. The analysis evaluates the impact of rod consolidation on CRWMS costs for consolidation at prior to transportation and for consolidation at the Monitored Geological Repository surface facility. For this study, no design changes were made to either the transport casks or waste packages. Waste package designs used for the Viability Assessment design were employed but derated to make the thermal limits. A logistics analysis of the waste was performed to determine the number of each waste package with each loading. A review of past rod consolidation experience found cost estimates which range from $10/kgU to $32/kgU. $30/kgU was assumed for rod consolidation costs prior to transportation. Transportation cost savings are about $17/kgU and waste package cost savings are about $21/kgU. The net saving to the system is approximately $500 million if the consolidation is performed prior to transportation. If consolidation were performed at the repository surface facilities, it would cost approximately $15/kgU. No transportation savings would be realized. The net savings for consolidation at the repository site would be about $400 million dollars.

  1. Flight experience of solar mesosphere explorer's power system over high temperatures ranges

    NASA Technical Reports Server (NTRS)

    Faber, Jack; Hurley, Daniel

    1987-01-01

    The performance of the power system on the Solar Mesosphere Explorer (SME) satellite for the life of the mission and the techniques used to ensure power system health are summarized. Early in the mission high cell imbalances in one of the batteries resulted in a loading scheme which attempted to minimize the cell imbalances without causing an undervoltage condition. A short term model of the power system allowed planners to predict depth of discharge using the latest available data. Due to expected orbital shifts the solar arrays experience extended periods of no eclipse. This has required special conditioning schemes to keep the batteries healthy when the eclipses return. Analysis of the SME data indicates long term health of the SME power system as long as the conditioning scheme is continued.

  2. Preoperative and Postoperative Range of Motion: A Retrospective Comparison of Two Total Ankle Replacement Systems.

    PubMed

    Brigido, Stephen A; Mulhern, Jennifer L; Wobst, Garrett M; Protzman, Nicole M

    2015-01-01

    The purpose of the present report was to compare the range of motion between a total ankle replacement requiring arched bony resection and a total ankle replacement requiring a flat cut for implantation. We hypothesized that the arched contour would more closely mimic the patient's pre-existing anatomy and increase the range of motion. Pain was evaluated as a secondary outcome. Twenty-eight patients (age 55.95 ± 15.29 years) were included. Of the 28 patients, 14 were treated with an arch cut and 14 with a flat cut. Although no significant difference was found in dorsiflexion between the 2 implant groups (p = .38), preoperative dorsiflexion, body mass index, implant type, and preoperative plantarflexion emerged as significant predictors of postoperative plantarflexion (p = .04). This finding indicates that postoperative plantarflexion was significantly greater in patients treated with an arch cut (30.43° ± 10.01°) than a flat cut (21.79° ± 15.70°, p = .02), when controlling for the other explanatory variables. A statistically significant improvement in pain was observed after total ankle replacement (p < .001). The mean change in pain was similar for the 2 implant groups when statistically controlling for the follow-up duration (p = .09). The findings from the present report suggest that plantarflexion significantly improves after total ankle replacement requiring an arched cut for implantation. Future studies should be designed to control for potentially confounding variables and assess the differences in range of motion after total ankle replacement.

  3. Renormalization of the Three-Body System with Short-Range Interactions

    NASA Astrophysics Data System (ADS)

    Bedaque, P. F.; Hammer, H.-W.; van Kolck, U.

    1999-01-01

    We discuss renormalization of the nonrelativistic three-body problem with short-range forces. The problem becomes nonperturbative at momenta of the order of the inverse of the two-body scattering length, and an infinite number of graphs must be summed. This summation leads to a cutoff dependence that does not appear in any order in perturbation theory. We argue that this cutoff dependence can be absorbed in a single three-body counterterm and compute the running of the three-body force with the cutoff. We comment on the relevance of this result for the effective field theory program in nuclear and molecular physics.

  4. Poxvirus viability and signatures in historical relics.

    PubMed

    McCollum, Andrea M; Li, Yu; Wilkins, Kimberly; Karem, Kevin L; Davidson, Whitni B; Paddock, Christopher D; Reynolds, Mary G; Damon, Inger K

    2014-02-01

    Although it has been >30 years since the eradication of smallpox, the unearthing of well-preserved tissue material in which the virus may reside has called into question the viability of variola virus decades or centuries after its original occurrence. Experimental data to address the long-term stability and viability of the virus are limited. There are several instances of well-preserved corpses and tissues that have been examined for poxvirus viability and viral DNA. These historical specimens cause concern for potential exposures, and each situation should be approached cautiously and independently with the available information. Nevertheless, these specimens provide information on the history of a major disease and vaccination against it.

  5. Poxvirus Viability and Signatures in Historical Relics

    PubMed Central

    Li, Yu; Wilkins, Kimberly; Karem, Kevin L.; Davidson, Whitni B.; Paddock, Christopher D.; Reynolds, Mary G.; Damon, Inger K.

    2014-01-01

    Although it has been >30 years since the eradication of smallpox, the unearthing of well-preserved tissue material in which the virus may reside has called into question the viability of variola virus decades or centuries after its original occurrence. Experimental data to address the long-term stability and viability of the virus are limited. There are several instances of well-preserved corpses and tissues that have been examined for poxvirus viability and viral DNA. These historical specimens cause concern for potential exposures, and each situation should be approached cautiously and independently with the available information. Nevertheless, these specimens provide information on the history of a major disease and vaccination against it. PMID:24447382

  6. Analysis of space target detection range based on space-borne fisheye imaging system in deep space background

    NASA Astrophysics Data System (ADS)

    Huang, Fuyu; Wang, Yongzhong; Shen, Xueju; Li, Gang; Yan, Shihua

    2012-11-01

    A space-borne photoelectric detection method is proposed based on the long wave infrared (LWIR, 8-14 μm) fisheye imaging system (LWIRFIS) in this paper. The existing detection range equation is modified to calculate the maximum detection ranges of the LWIRFIS for space targets, and the influence of several key parameters is discussed in detail. The results show that, the system maximum detection range increases with the decrease of the half-field angle, the increase of the target area, the rise of the target temperature, the drop of the optics temperature, and the reduction of the system threshold signal-to-noise ratio. The detection range can be improved greatly through taking measures to optimize the latter two system parameters, such as setting up diaphragms, controlling the operating temperature, suppressing the noises by software or hardware methods. This work lays the foundation for the further research of space-borne super-wide field of view (FOV) imaging system, and provides a useful exploration for improving the capability of space situation awareness (SSA) of the space-borne observation platform.

  7. Long-Range Forces in the Li + Li2 and Na + Na2 Systems

    NASA Astrophysics Data System (ADS)

    Bent, Gary D.; Michels, H. Harvey

    2003-05-01

    The interaction potentials for the approach of a lithium atom to the lithium molecule and a sodium atom to the sodium molecule were calculated from 15 Ådown to the equilibrium geometry of the trimers. The emphasis of the calculations was to find the minimum energy paths and examine the asymptotic behavior of the approaches in order to obtain an accurate representation of the long-range forces. The CBS method of Petersson, et al was used in order to determine the intermolecular forces to a high degree of accuracy. The long-range behavior of Li + Li2 -> Li3 was compared to the three-body dispersion coefficient calculated for Li3 by Marinescu and Starace and the Li + Li2 dispersion terms of Varandas and Pais. The agreement of the ab initio calculations with the work of Varandas and Pais was excellent. The agreement with the work of Marinescu and Starace was satisfactory until 10 Åwhere their results began to diverge from our calculations. This is attributed to the observation that they considered only the C6 dispersion term.

  8. 780nm-range VCSEL array for laser printer system and other applications at Ricoh

    NASA Astrophysics Data System (ADS)

    Jikutani, Naoto; Itoh, Akihiro; Harasaka, Kazuhiro; Sasaki, Toshihide; Sato, Shunichi

    2016-03-01

    A 780 nm-range 40 channels vertical-cavity surface-emitting laser (VCSEL) array was developed as a writing light source for printers. A 15° off missoriented GaAs substrate, an aluminum-free GaInAsP/GaInP compressively-strained multiple quantum well and an anisotropic-shape transverse-mode filter were employed to control polarization characteristics. The anisotropic-shape transverse-mode filter also suppressed higher transverse-mode and enabled high-power single-mode operation. Thus, orthogonal-polarization suppression-ratio (OPSR) of over 22 dB and side-mode suppression-ratio (SMSR) of 30 dB were obtained at operation power of 3mW at same time for wide oxide-aperture range below 50 μm2. Moreover, a thermal resistance was reduced for 38% by increasing a thickness of high thermal conductivity layer (3λ/4-AlAs layer) near a cavity. By this structure, a peak-power increased to 1.3 times. Moreover, a power-fall caused by self-heating at pulse-rise was decreased to 10% and the one caused by a thermal-crosstalk between channels was decreased to 46%. The VCSEL array was mounted in a ceramic package with a tilted seal glass to prevent optical-crosstalk caused by other channels. Thus, we achieved stable-output and high-quality beam characteristics for long-duration pulse drive.

  9. System for performing site characterization for test ranges containing unexploded ordnance

    NASA Astrophysics Data System (ADS)

    Brown, H. Edward; Crane, Carl D., III

    1996-05-01

    Wright Laboratory has been tasked by the Naval Explosive Ordnance Technical Division to develop robotic platforms to perform characterization of areas set aside for ordnance testing. These areas require the identification and removal of the unexploded ordnance before they can be utilized for safe, productive use. The characterization task is performed by autonomously sweeping a designated area with the autonomous tow vehicle (ATV). The ATV tows the multiple sensor platform containing a magnetometer array and a ground penetrating radar. The ATV provides the time and position stamp for sensor data. Analysts then review the post survey sensor data to determine ordnance position. The ATV makes use of several advanced technologies. A hybrid navigation and guidance system using an external Kalman filter delivers vehicle position based on information from a real time centimeter level differential global positioning system and a strapped down laser gyro inertial navigation system. A vision-based obstacle avoidance system helps to account for unknown obstacles during survey. Sophisticated path planning algorithms, and an intelligent software architecture for planning and behavior provide a measure of autonomy. A data collection system controls the functions of the various sensors used for the characterization process and manipulates the data stream to conform to an open ASCII data format and stores it to rugged removable hard disks for later analysis.

  10. Expert system-based design of close-range photogrammetric networks

    NASA Astrophysics Data System (ADS)

    Mason, Scott

    Designing an appropriate multi-station, convergent network is a prerequisite to the realization of high-accuracy photogrammetric measurement in industrial applications. Such networks are in practice designed by a simulation approach in which the expertise of the photogrammetrist is relied upon to overcome the complexity of the task. This article reports on investigations into the feasibility of an expert system solution to the automation of this design task. Major findings include recommendations for the representation of network design expertise, network topology and spatial information, the appropriate architecture for an expert system-based tool, development of conceptual models for camera placement and network diagnosis, and a computational model for camera placement. The prototype expert system CONSENS was built to test these concepts and models. Experiments with it confirm the feasibility of the approach. Prospects for application of this approach in photogrammetric practice, as well as limitations, are identified.

  11. Free range and deep litter poultry production systems: effect on performance, carcass yield and meat composition of cockerel chickens.

    PubMed

    Sogunle, Olajide Mark; Olaniyi, Olagoke Ayobami; Egbeyale, Lawrence Tokunbo; Akinola, Olufemi Sunday; Shittu, Taofeek A; Abiola, Samuel Soladoye; Ladokun, Abimbola O; Sobayo, Richard Abayomi

    2013-01-01

    This study was carried out on 150 cockerel chickens each of Harco Black and Novogen strains to determine their performance, carcass yield and meat composition on free range and deep litter production systems. The birds were brooded for 4 weeks and thereafter allotted to the different production systems for a period of 12 weeks. Each production system was allotted 150 chicks (75 chicks per strain) with three replicates of 25 chicks. The birds on deep litter production system were fed ad libitum while each bird on free range was fed 50 % of its daily feed requirement. On the 84 th day, a total of 36 birds were randomly selected for analysis of the carcass yield and meat composition. The data generated were subjected to a two-way analysis of variance in a 2 × 2 factorial experimental arrangement. Novogen strain consumed less feed (P < 0.05) on free range and had the best feed/gain (2.72). A higher (P < 0.05) shear force value (3.74 N) was obtained in the thigh muscle for birds on free range. The tibia proximal length and breadth, and tibia distal length and breadth were significantly (P < 0.05) affected by the production systems and strains. On free range, Harco black had more meat (85.69 g) than bone (18.07 g) in the breast while Novogen had the lowest meat/bone (2.38). Conclusively, Novogen strain should be raised on free range for a better performance in terms of feed/gain, but for higher meat composition, Harco black is a better strain.

  12. Compositional and physicochemical factors governing the viability of Lactobacillus rhamnosus GG embedded in starch-protein based edible films

    PubMed Central

    Soukoulis, Christos; Singh, Poonam; Macnaughtan, William; Parmenter, Christopher; Fisk, Ian D.

    2016-01-01

    Probiotic incorporation in edible films and coatings has been shown recently to be an efficient strategy for the delivery of probiotics in foods. In the present work, the impact of the compositional, physicochemical and structural properties of binary starch-protein edible films on Lactobacillus rhamnosus GG viability and stability was evaluated. Native rice and corn starch, as well as bovine skin gelatine, sodium caseinate and soy protein concentrate were used for the fabrication of the probiotic edible films. Starch and protein type both impacted the structural, mechanical, optical and thermal properties of the films, and the process loss of L. rhamnosus GG during evaporation-dehydration was significantly lower in the presence of proteins (0.91–1.07 log CFU/g) compared to solely starch based systems (1.71 log CFU/g). A synergistic action between rice starch and proteins was detected when monitoring the viability of L. rhamnosus GG over four weeks at fridge and room temperature conditions. In particular, a 3- to 7-fold increase in the viability of L. rhamnosus GG was observed in the presence of proteins, with sodium caseinate – rice starch based films offering the most enhanced stability. The film's shelf-life (as calculated using the FAO/WHO (2011) basis of 6 log viable CFU/g) ranged between 27-96 and 15–24 days for systems stored at fridge or room temperature conditions respectively. PMID:26726280

  13. a Uav Based Close-Range Rapid Aerial Monitoring System for Emergency Responses

    NASA Astrophysics Data System (ADS)

    Choi, K.; Lee, I.

    2011-09-01

    As the occurrences and scales of disasters and accidents have been increased due to the global warming, the terrorists' attacks, and many other reasons, the demand for rapid responses for the emergent situations also has been thus ever-increasing. These emergency responses are required to be customized to each individual site for more effective management of the emergent situations. These requirements can be satisfied with the decisions based on the spatial changes on the target area, which should be detected immediately or in real-time. Aerial monitoring without human operators is an appropriate means because the emergency areas are usually inaccessible. Therefore, a UAV is a strong candidate as the platform for the aerial monitoring. In addition, the sensory data from the UAV system usually have higher resolution than other system because the system can operate at a lower altitude. If the transmission and processing of the data could be performed in real-time, the spatial changes of the target area can be detected with high spatial and temporal resolution by the UAV rapid mapping systems. As a result, we aim to develop a rapid aerial mapping system based on a UAV, whose key features are the effective acquisition of the sensory data, real-time transmission and processing of the data. In this paper, we will introduce the general concept of our system, including the main features, intermediate results, and explain our real-time sensory data georeferencing algorithm which is a core for prompt generation of the spatial information from the sensory data.

  14. A survey of the state-of-the-art and focused research in range systems

    NASA Technical Reports Server (NTRS)

    Kung, Yao; Balakrishnan, A. V.

    1988-01-01

    In this one-year renewal of NASA Contract No. 2-304, basic research, development, and implementation in the areas of modern estimation algorithms and digital communication systems have been performed. In the first area, basic study on the conversion of general classes of practical signal processing algorithms into systolic array algorithms is considered, producing four publications. Also studied were the finite word length effects and convergence rates of lattice algorithms, producing two publications. In the second area of study, the use of efficient importance sampling simulation technique for the evaluation of digital communication system performances were studied, producing two publications.

  15. Cryocooled terahertz photoconductive detector system with background-limited performance in 1.5–4 THz frequency range

    SciTech Connect

    Aoki, Makoto; Hiromoto, Norihisa

    2015-10-15

    We describe a 4-K-cryocooled dual-band terahertz (THz) photoconductive detector system with background-limited performance. The detector system comprises two THz photoconductive detectors covering a response in a wide frequency range from 1.5 to 4 THz, low noise amplifiers, optical low-pass filters to eliminate input radiation of higher frequencies, and a mechanical 4 K Gifford-McMahon refrigerator that provides practical and convenient operation without a liquid He container. The electrical and optical performances of the THz detector system were evaluated at a detector temperature of 4 K under 300 K background radiation. We proved that the detector system can achieve background-limited noise-equivalent-power on the order of 10{sup −14} W/Hz{sup 1/2} in the frequency range from 1.5 to 4 THz even if the vibration noise of the mechanical refrigerator is present.

  16. Excitation, detection, and electrostatic manipulation of terahertz-frequency range plasmons in a two-dimensional electron system

    NASA Astrophysics Data System (ADS)

    Wu, Jingbo; Mayorov, Alexander S.; Wood, Christopher D.; Mistry, Divyang; Li, Lianhe; Muchenje, Wilson; Rosamond, Mark C.; Chen, Li; Linfield, Edmund H.; Davies, A. Giles; Cunningham, John E.

    2015-10-01

    Terahertz frequency time-domain spectroscopy employing free-space radiation has frequently been used to probe the elementary excitations of low-dimensional systems. The diffraction limit, however, prevents its use for the in-plane study of individual laterally-defined nanostructures. Here, we demonstrate a planar terahertz frequency plasmonic circuit in which photoconductive material is monolithically integrated with a two-dimensional electron system. Plasmons with a broad spectral range (up to ~ 400 GHz) are excited by injecting picosecond-duration pulses, generated and detected by a photoconductive semiconductor, into a high mobility two-dimensional electron system. Using voltage modulation of a Schottky gate overlying the two-dimensional electron system, we form a tuneable plasmonic cavity, and observe electrostatic manipulation of the plasmon resonances. Our technique offers a direct route to access the picosecond dynamics of confined electron transport in a broad range of lateral nanostructures.

  17. Excitation, detection, and electrostatic manipulation of terahertz-frequency range plasmons in a two-dimensional electron system.

    PubMed

    Wu, Jingbo; Mayorov, Alexander S; Wood, Christopher D; Mistry, Divyang; Li, Lianhe; Muchenje, Wilson; Rosamond, Mark C; Chen, Li; Linfield, Edmund H; Davies, A Giles; Cunningham, John E

    2015-01-01

    Terahertz frequency time-domain spectroscopy employing free-space radiation has frequently been used to probe the elementary excitations of low-dimensional systems. The diffraction limit, however, prevents its use for the in-plane study of individual laterally-defined nanostructures. Here, we demonstrate a planar terahertz frequency plasmonic circuit in which photoconductive material is monolithically integrated with a two-dimensional electron system. Plasmons with a broad spectral range (up to ~ 400 GHz) are excited by injecting picosecond-duration pulses, generated and detected by a photoconductive semiconductor, into a high mobility two-dimensional electron system. Using voltage modulation of a Schottky gate overlying the two-dimensional electron system, we form a tuneable plasmonic cavity, and observe electrostatic manipulation of the plasmon resonances. Our technique offers a direct route to access the picosecond dynamics of confined electron transport in a broad range of lateral nanostructures. PMID:26487263

  18. Cryocooled terahertz photoconductive detector system with background-limited performance in 1.5-4 THz frequency range.

    PubMed

    Aoki, Makoto; Hiromoto, Norihisa

    2015-10-01

    We describe a 4-K-cryocooled dual-band terahertz (THz) photoconductive detector system with background-limited performance. The detector system comprises two THz photoconductive detectors covering a response in a wide frequency range from 1.5 to 4 THz, low noise amplifiers, optical low-pass filters to eliminate input radiation of higher frequencies, and a mechanical 4 K Gifford-McMahon refrigerator that provides practical and convenient operation without a liquid He container. The electrical and optical performances of the THz detector system were evaluated at a detector temperature of 4 K under 300 K background radiation. We proved that the detector system can achieve background-limited noise-equivalent-power on the order of 10(-14) W/Hz(1/2) in the frequency range from 1.5 to 4 THz even if the vibration noise of the mechanical refrigerator is present.

  19. Excitation, detection, and electrostatic manipulation of terahertz-frequency range plasmons in a two-dimensional electron system

    PubMed Central

    Wu, Jingbo; Mayorov, Alexander S.; Wood, Christopher D.; Mistry, Divyang; Li, Lianhe; Muchenje, Wilson; Rosamond, Mark C.; Chen, Li; Linfield, Edmund H.; Davies, A. Giles; Cunningham, John E.

    2015-01-01

    Terahertz frequency time-domain spectroscopy employing free-space radiation has frequently been used to probe the elementary excitations of low-dimensional systems. The diffraction limit, however, prevents its use for the in-plane study of individual laterally-defined nanostructures. Here, we demonstrate a planar terahertz frequency plasmonic circuit in which photoconductive material is monolithically integrated with a two-dimensional electron system. Plasmons with a broad spectral range (up to ~ 400 GHz) are excited by injecting picosecond-duration pulses, generated and detected by a photoconductive semiconductor, into a high mobility two-dimensional electron system. Using voltage modulation of a Schottky gate overlying the two-dimensional electron system, we form a tuneable plasmonic cavity, and observe electrostatic manipulation of the plasmon resonances. Our technique offers a direct route to access the picosecond dynamics of confined electron transport in a broad range of lateral nanostructures. PMID:26487263

  20. Effects of Fluid Shear Stress on Cancer Stem Cell Viability

    NASA Astrophysics Data System (ADS)

    Sunday, Brittney; Triantafillu, Ursula; Domier, Ria; Kim, Yonghyun

    2014-11-01

    Cancer stem cells (CSCs), which are believed to be the source of tumor formation, are exposed to fluid shear stress as a result of blood flow within the blood vessels. It was theorized that CSCs would be less susceptible to cell death than non-CSCs after both types of cell were exposed to a fluid shear stress, and that higher levels of fluid shear stress would result in lower levels of cell viability for both cell types. To test this hypothesis, U87 glioblastoma cells were cultured adherently (containing smaller populations of CSCs) and spherically (containing larger populations of CSCs). They were exposed to fluid shear stress in a simulated blood flow through a 125-micrometer diameter polyetheretherketone (PEEK) tubing using a syringe pump. After exposure, cell viability data was collected using a BioRad TC20 Automated Cell Counter. Each cell type was tested at three physiological shear stress values: 5, 20, and 60 dynes per centimeter squared. In general, it was found that the CSC-enriched U87 sphere cells had higher cell viability than the CSC-depleted U87 adherent cancer cells. Interestingly, it was also observed that the cell viability was not negatively affected by the higher fluid shear stress values in the tested range. In future follow-up studies, higher shear stresses will be tested. Furthermore, CSCs from different tumor origins (e.g. breast tumor, prostate tumor) will be tested to determine cell-specific shear sensitivity. National Science Foundation Grant #1358991 supported the first author as an REU student.

  1. Range effects of the Coulombic forces on structures, thermodynamic properties and potential energy landscapes: (KCl)32 and related systems

    NASA Astrophysics Data System (ADS)

    Wang, Chengju; Stephen Berry, R.; Jellinek, Julius

    2012-05-01

    By introducing two shielding parameters into the Coulombic part of the Coulomb plus Born-Mayer potential originally developed for (KCl)n systems, we study the effects of the range of the Coulombic interactions on the structures, thermodynamic properties and the potential energy landscapes of binary ionically bonded systems as illustrated by the case of n = 32. Our calculations show that shortening of the Coulomb interaction range leads to a decrease in the energy of the most stable structure, and the structure itself changes from the rocksalt cubic to a hollow cage type. The energy range, in which the heat capacity exhibits a negative value, gradually narrows and eventually disappears. The number of stationary points on the potential energy surface increases, and their energies get spread over a larger interval. The extent of the Coulombic interaction also affects the energy difference (gap) between the most stable structure and the structure that follows it. All these changes translate into changes in the melting behavior of the system. An analysis of the melting behavior as a function of the range of the Coulombic interaction is presented and correlated with the range-dependent changes in the topography of the underlying potential energy surface.

  2. Sample transfer system for surface studies in wide pressure range (10-7-106 Pa)

    NASA Astrophysics Data System (ADS)

    Ichikawa, Shinichi; Wilson, Mahlon S.

    1987-02-01

    An inexpensive sample transfer system suitable for surface studies with in situ prepared model catalysts is described. Experiments from ultrahigh vacuum to 10 atm and 50-cm travel with negligible pressure spikes were made possible by the use of double-seal glands with spring-loaded Teflon O-rings and a guided rotational transport rod.

  3. A survey of the state of the art and focused research in range systems, task 2

    NASA Technical Reports Server (NTRS)

    Yao, K.

    1986-01-01

    Many communication, control, and information processing subsystems are modeled by linear systems incorporating tapped delay lines (TDL). Such optimized subsystems result in full precision multiplications in the TDL. In order to reduce complexity and cost in a microprocessor implementation, these multiplications can be replaced by single-shift instructions which are equivalent to powers of two multiplications. Since, in general, the obvious operation of rounding the infinite precision TDL coefficients to the nearest powers of two usually yield quite poor system performance, the optimum powers of two coefficient solution was considered. Detailed explanations on the use of branch-and-bound algorithms for finding the optimum powers of two solutions are given. Specific demonstration of this methodology to the design of a linear data equalizer and its implementation in assembly language on a 8080 microprocessor with a 12 bit A/D converter are reported. This simple microprocessor implementation with optimized TDL coefficients achieves a system performance comparable to the optimum linear equalization with full precision multiplications for an input data rate of 300 baud. The philosophy demonstrated in this implementation is dully applicable to many other microprocessor controlled information processing systems.

  4. Practical Applications of Space Systems, Supporting Paper 4: Agriculture, Forest, and Range.

    ERIC Educational Resources Information Center

    National Academy of Sciences - National Research Council, Washington, DC. Assembly of Engineering.

    This report summarizes the findings of one of fourteen panels that studied the progress of space science applications and defined user needs potentially capable of being met by space-system applications. The study was requested by the National Aeronautics and Space Administration (NASA) and was conducted by the Space Applications Board. The panels…

  5. Local Oscillator Sub-Systems for Array Receivers in the 1-3 THz Range

    NASA Technical Reports Server (NTRS)

    Mehdi, Imran; Siles, Jose V.; Maestrini, Alain; Lin, Robert; Lee, Choonsup; Schlecht, Erich; Chattopadhyay, Goutam

    2012-01-01

    Recent results from the Heterodyne Instrument for the Far-Infrared (HIFI) on the Herschel Space Telescope have confirmed the usefulness of high resolution spectroscopic data for a better understanding of our Universe. This paper will explore the current status of tunable local oscillator sources with emphasis on building a multi-pixel LO subsystem for the scientifically important CII line around 1908 GHz. Recent results have shown that over 50 microwatts of output power at 1.9 THz are possible with an optimized single pixel LO chain. These power levels are now sufficient to pump array receivers in this frequency range. Further power enhancement can be obtained by cooling the chain to 120 K or by utilizing in-phase power combining technology.

  6. Theoretical and experimental analyses of the performance of two-color laser ranging systems

    NASA Technical Reports Server (NTRS)

    Im, K. E.; Gardner, C. S.

    1985-01-01

    The statistical properties of the signals reflected from the retroreflector equipped satellites were studied. It is found that coherence interference between pulse reflections from retroreflectors of different ranges on the array platform is the primary cause of signal fluctuations. The performance of a cross-correlation technique to estimate the differential propagation time is analyzed by considering both shot noise and speckle. For the retroreflector arrays, timing performance is dominated by interference induced speckle, and the differential propagation time cannot be resolved to better than the pulse widths of the received signals. The differential timing measurements obtained over a horizontal path are analyzed. The ocean-reflected pulse measurements obtained from the airborne two-color laser altimeter experiment are presented.

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

    NASA Astrophysics Data System (ADS)

    Boyer, Kim L.; Goddard, Ralph E.

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

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

    NASA Technical Reports Server (NTRS)

    Boyer, Kim L.; Goddard, Ralph E.

    1991-01-01

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

  9. Rabbit System. Low cost, high reliability front end electronics featuring 16 bit dynamic range. [Redundant Analog Bus Based Information Transfer

    SciTech Connect

    Drake, G.; Droege, T.F.; Nelson, C.A. Jr.; Turner, K.J.; Ohska, T.K.

    1985-10-01

    A new crate-based front end system has been built which features low cost, compact packaging, command capability, 16 bit dynamic range digitization, and a high degree of redundancy. The crate can contain a variety of instrumentation modules, and is designed to be situated close to the detector. The system is suitable for readout of a large number of channels via parallel multiprocessor data acquisition.

  10. Measured electric field intensities near electric cloud discharges detected by the Kennedy Space Center's Lightning Detection and Ranging System, LDAR

    NASA Technical Reports Server (NTRS)

    Poehler, H. A.

    1977-01-01

    For a summer thunderstorm, for which simultaneous, airborne electric field measurements and Lightning Detection and Ranging (LDAR) System data was available, measurements were coordinated to present a picture of the electric field intensity near cloud electrical discharges detected by the LDAR System. Radar precipitation echos from NOAA's 10 cm weather radar and measured airborne electric field intensities were superimposed on LDAR PPI plots to present a coordinated data picture of thunderstorm activity.

  11. 24 CFR 971.5 - Long-term viability.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Long-term viability. 971.5 Section...-term viability. (a) Reasonable investment. (1) Proposed revitalization costs for viability must be... ensure viability and to sustain the operating costs that are described in paragraph (a)(2) of...

  12. Determining position, velocity and acceleration of free-ranging animals with a low-cost unmanned aerial system.

    PubMed

    Harvey, Richard J; Roskilly, Kyle; Buse, Chris; Evans, Hannah K; Hubel, Tatjana Y; Wilson, Alan M

    2016-09-01

    Unmanned aerial systems (UASs), frequently referred to as 'drones', have become more common and affordable and are a promising tool for collecting data on free-ranging wild animals. We used a Phantom-2 UAS equipped with a gimbal-mounted camera to estimate position, velocity and acceleration of a subject on the ground moving through a grid of GPS surveyed ground control points (area ∼1200 m(2)). We validated the accuracy of the system against a dual frequency survey grade GPS system attached to the subject. When compared with GPS survey data, the estimations of position, velocity and acceleration had a root mean square error of 0.13 m, 0.11 m s(-1) and 2.31 m s(-2), respectively. The system can be used to collect locomotion and localisation data on multiple free-ranging animals simultaneously. It does not require specialist skills to operate, is easily transported to field locations, and is rapidly and easily deployed. It is therefore a useful addition to the range of methods available for field data collection on free-ranging animal locomotion.

  13. Receiver design, performance analysis, and evaluation for space-borne laser altimeters and space-to-space laser ranging systems

    NASA Technical Reports Server (NTRS)

    Davidson, Frederic M.; Sun, Xiaoli; Field, Christopher T.

    1994-01-01

    Accomplishments in the following areas of research are presented: receiver performance study of spaceborne laser altimeters and cloud and aerosol lidars; receiver performance analysis for space-to-space laser ranging systems; and receiver performance study for the Mars Environmental Survey (MESUR).

  14. Determining position, velocity and acceleration of free-ranging animals with a low-cost unmanned aerial system.

    PubMed

    Harvey, Richard J; Roskilly, Kyle; Buse, Chris; Evans, Hannah K; Hubel, Tatjana Y; Wilson, Alan M

    2016-09-01

    Unmanned aerial systems (UASs), frequently referred to as 'drones', have become more common and affordable and are a promising tool for collecting data on free-ranging wild animals. We used a Phantom-2 UAS equipped with a gimbal-mounted camera to estimate position, velocity and acceleration of a subject on the ground moving through a grid of GPS surveyed ground control points (area ∼1200 m(2)). We validated the accuracy of the system against a dual frequency survey grade GPS system attached to the subject. When compared with GPS survey data, the estimations of position, velocity and acceleration had a root mean square error of 0.13 m, 0.11 m s(-1) and 2.31 m s(-2), respectively. The system can be used to collect locomotion and localisation data on multiple free-ranging animals simultaneously. It does not require specialist skills to operate, is easily transported to field locations, and is rapidly and easily deployed. It is therefore a useful addition to the range of methods available for field data collection on free-ranging animal locomotion. PMID:27353230

  15. Dense range map reconstruction from a versatile robotic sensor system with an active trinocular vision and a passive binocular vision

    NASA Astrophysics Data System (ADS)

    Kim, Min Young; Lee, Hyunkee; Cho, Hyungsuck

    2008-04-01

    One major research issue associated with 3D perception by robotic systems is the creation of efficient sensor systems that can generate dense range maps reliably. A visual sensor system for robotic applications is developed that is inherently equipped with two types of sensor, an active trinocular vision and a passive stereo vision. Unlike in conventional active vision systems that use a large number of images with variations of projected patterns for dense range map acquisition or from conventional passive vision systems that work well on specific environments with sufficient feature information, a cooperative bidirectional sensor fusion method for this visual sensor system enables us to acquire a reliable dense range map using active and passive information simultaneously. The fusion algorithms are composed of two parts, one in which the passive stereo vision helps active vision and the other in which the active trinocular vision helps the passive one. The first part matches the laser patterns in stereo laser images with the help of intensity images; the second part utilizes an information fusion technique using the dynamic programming method in which image regions between laser patterns are matched pixel-by-pixel with help of the fusion results obtained in the first part. To determine how the proposed sensor system and fusion algorithms can work in real applications, the sensor system is implemented on a robotic system, and the proposed algorithms are applied. A series of experimental tests is performed for a variety of configurations of robot and environments. The performance of the sensor system is discussed in detail.

  16. Dense range map reconstruction from a versatile robotic sensor system with an active trinocular vision and a passive binocular vision.

    PubMed

    Kim, Min Young; Lee, Hyunkee; Cho, Hyungsuck

    2008-04-10

    One major research issue associated with 3D perception by robotic systems is the creation of efficient sensor systems that can generate dense range maps reliably. A visual sensor system for robotic applications is developed that is inherently equipped with two types of sensor, an active trinocular vision and a passive stereo vision. Unlike in conventional active vision systems that use a large number of images with variations of projected patterns for dense range map acquisition or from conventional passive vision systems that work well on specific environments with sufficient feature information, a cooperative bidirectional sensor fusion method for this visual sensor system enables us to acquire a reliable dense range map using active and passive information simultaneously. The fusion algorithms are composed of two parts, one in which the passive stereo vision helps active vision and the other in which the active trinocular vision helps the passive one. The first part matches the laser patterns in stereo laser images with the help of intensity images; the second part utilizes an information fusion technique using the dynamic programming method in which image regions between laser patterns are matched pixel-by-pixel with help of the fusion results obtained in the first part. To determine how the proposed sensor system and fusion algorithms can work in real applications, the sensor system is implemented on a robotic system, and the proposed algorithms are applied. A series of experimental tests is performed for a variety of configurations of robot and environments. The performance of the sensor system is discussed in detail.

  17. Confidence range estimate of extended source imagery acquisition algorithms via computer simulations. [in optical communication systems

    NASA Technical Reports Server (NTRS)

    Chen, CHIEN-C.; Hui, Elliot; Okamoto, Garret

    1992-01-01

    Spatial acquisition using the sun-lit Earth as a beacon source provides several advantages over active beacon-based systems for deep-space optical communication systems. However, since the angular extend of the Earth image is large compared to the laser beam divergence, the acquisition subsystem must be capable of resolving the image to derive the proper pointing orientation. The algorithms used must be capable of deducing the receiver location given the blurring introduced by the imaging optics and the large Earth albedo fluctuation. Furthermore, because of the complexity of modelling the Earth and the tracking algorithms, an accurate estimate of the algorithm accuracy can only be made via simulation using realistic Earth images. An image simulator was constructed for this purpose, and the results of the simulation runs are reported.

  18. 3D sensor placement strategy using the full-range pheromone ant colony system

    NASA Astrophysics Data System (ADS)

    Shuo, Feng; Jingqing, Jia

    2016-07-01

    An optimized sensor placement strategy will be extremely beneficial to ensure the safety and cost reduction considerations of structural health monitoring (SHM) systems. The sensors must be placed such that important dynamic information is obtained and the number of sensors is minimized. The practice is to select individual sensor directions by several 1D sensor methods and the triaxial sensors are placed in these directions for monitoring. However, this may lead to non-optimal placement of many triaxial sensors. In this paper, a new method, called FRPACS, is proposed based on the ant colony system (ACS) to solve the optimal placement of triaxial sensors. The triaxial sensors are placed as single units in an optimal fashion. And then the new method is compared with other algorithms using Dalian North Bridge. The computational precision and iteration efficiency of the FRPACS has been greatly improved compared with the original ACS and EFI method.

  19. Enhancement of the magnetic anisotropy barrier in critical long range spin systems.

    PubMed

    Borgonovi, F; Celardo, G L

    2013-03-13

    Magnetic materials are usually characterized by anisotropy energy barriers which dictate the timescale of the magnetization decay and consequently the magnetic stability of the sample. Here we consider magnetization decay for spin systems in a d = 3 cubic lattice with an isotropic Heisenberg interaction decaying as a power law with a critical exponent α = d and on-site anisotropy. We show that the anisotropy energy barrier can be determined from the ergodicity breaking energy of the corresponding isolated system and that, unlike in the case of nearest neighbour interaction, the anisotropy energy barrier grows as the particle volume, V, and not as the cross-sectional area.

  20. Method and system for controlling a synchronous machine over full operating range

    DOEpatents

    Walters, James E.; Gunawan, Fani S.; Xue, Yanhong

    2002-01-01

    System and method for controlling a synchronous machine are provided. The method allows for calculating a stator voltage index. The method further allows for relating the magnitude of the stator voltage index against a threshold voltage value. An offset signal is generated based on the results of the relating step. A respective state of operation of the machine is determined. The offset signal is processed based on the respective state of the machine.

  1. Evaluation of range parameters of the cameras for security system protecting the selected critical infrastructure of seaport

    NASA Astrophysics Data System (ADS)

    Kastek, Mariusz; Barela, Jaroslaw; Zyczkowski, Marek; Dulski, Rafal; Trzaskawka, Piotr; Firmanty, Krzysztof; Kucharz, Juliusz

    2012-10-01

    There are many separated infrastructural objects within a harbor area that may be considered "critical", such as gas and oil terminals or anchored naval vessels. Those objects require special protection, including security systems capable of monitoring both surface and underwater areas, because an intrusion into the protected area may be attempted using small surface vehicles (boats, kayaks, rafts, floating devices with weapons and explosives) as well as underwater ones (manned or unmanned submarines, scuba divers). The cameras used in security systems operate in several different spectral ranges in order to improve the probability of detection of incoming objects (potential threats). The cameras should then have adequate range parameters for detection, recognition and identification and those parameters, both measured and obtained through numerical simulations, will be presented in the paper. The range parameters of thermal cameras were calculated using NVTherm software package. Parameters of four observation thermal cameras were also measured on a specialized test stand at Institute of Optoelectronics, MUT. This test stand makes it also possible to test visual cameras. The parameters of five observation cameras working in the visual range were measured and on the basis of those data the detection, recognition and identification ranges were determined. The measurement results and simulation data will be compared. The evaluation of range parameters obtained for the tested camera types will define their usability in the real security system for the protection of selected critical infrastructure of a seaport.small surface objects (such as RIB boats) by a camera system and real test results in various weather conditions will also be presented.

  2. A computer model of human thermoregulation for a wide range of environmental conditions: the passive system.

    PubMed

    Fiala, D; Lomas, K J; Stohrer, M

    1999-11-01

    A dynamic model predicting human thermal responses in cold, cool, neutral, warm, and hot environments is presented in a two-part study. This, the first paper, is concerned with aspects of the passive system: 1) modeling the human body, 2) modeling heat-transport mechanisms within the body and at its periphery, and 3) the numerical procedure. A paper in preparation will describe the active system and compare the model predictions with experimental data and the predictions by other models. Here, emphasis is given to a detailed modeling of the heat exchange with the environment: local variations of surface convection, directional radiation exchange, evaporation and moisture collection at the skin, and the nonuniformity of clothing ensembles. Other thermal effects are also modeled: the impact of activity level on work efficacy and the change of the effective radiant body area with posture. A stable and accurate hybrid numerical scheme was used to solve the set of differential equations. Predictions of the passive system model are compared with available analytic solutions for cylinders and spheres and show good agreement and stable numerical behavior even for large time steps.

  3. Wireless Laser Range Finder System for Vertical Displacement Monitoring of Mega-Trusses during Construction

    PubMed Central

    Park, Hyo Seon; Son, Sewook; Choi, Se Woon; Kim, Yousok

    2013-01-01

    As buildings become increasingly complex, construction monitoring using various sensors is urgently needed for both more systematic and accurate safety management and high-quality productivity in construction. In this study, a monitoring system that is composed of a laser displacement sensor (LDS) and a wireless sensor node was proposed and applied to an irregular building under construction. The subject building consists of large cross-sectional members, such as mega-columns, mega-trusses, and edge truss, which secured the large spaces. The mega-trusses and edge truss that support this large space are of the cantilever type. The vertical displacement occurring at the free end of these members was directly measured using an LDS. To validate the accuracy and reliability of the deflection data measured from the LDS, a total station was also employed as a sensor for comparison with the LDS. In addition, the numerical simulation result was compared with the deflection obtained from the LDS and total station. Based on these investigations, the proposed wireless displacement monitoring system was able to improve the construction quality by monitoring the real-time behavior of the structure, and the applicability of the proposed system to buildings under construction for the evaluation of structural safety was confirmed. PMID:23648650

  4. Fetal viability as a threshold to personhood. A legal analysis.

    PubMed

    Peterfy, A

    1995-12-01

    This essay opens with an examination of US laws concerning fetal viability as they apply to induced abortion, to a mother's right to refuse medical treatment necessary to save the life of a fetus, and to the rights to file suit for the wrongful death of unborn children. The history of abortion policies in the US is traced from the common law period of the early 19th century to the restrictive post-Civil War laws and the decisions of the Supreme Court in Roe vs. Wade, which upheld the constitutionality of previability abortions; Webster vs. Reproductive Health Services, in which the Court assigned viability to the 20th week of pregnancy and acknowledged that States could have a compelling previability interest in the fetus; and the Casey decision, which provided tolerance for limits on the availability of abortion before viability as long as the limits did not create an "undue burden" on the woman seeking the abortion. Courts dealing with the issue of compelling a mother to undergo medical treatment to save her fetus have been inconsistent as they balanced the state's interest in the fetus against the mother's rights to privacy. Judges have tended to err on the side of forcing the medical interventions, but the most recent trend is against this sort of judgement. In these cases, fetal viability has also served as a dividing line. The inconsistency of the legal system is illustrated by the fact that, whereas the fetus now has a legal existence, wrongful death actions entered on behalf of a nonviable fetus have often been denied although courts have been more willing to extend protection to fetuses in wrongful death tort cases than in abortion or medical intervention cases. Criminal law has a unique set of rules for dealing with fetuses as some states have broadened their definitions of "homicide" to include fetuses, even nonviable fetuses. Courts, however, are reluctant to enlarge criminal statutes on their own. While the central position given to the role of

  5. Image enhancement using a range gated MCPII video system with a 180-ps FWHM shutter

    SciTech Connect

    Thomas, M.C.; Yates, G.J.; Zadgarino, P.

    1995-09-01

    The video image of a target submerged in a scattering medium was improved through the use of range gating techniques. The target, an Air Force resolution chart, was submerged in 18 in. of a colloidal suspension of tincture green soap in water. The target was illuminated with pulsed light from a Raman shifted, frequency-doubled, ND:YAG laser having a wavelength of 559 mm and a width of 20 ps FWHM. The laser light reflected by the target along with the light scattered by the soap, was imaged onto a microchannel-plate image intensifier (MCPII). The output from the MCPII was then recorded with a RS-170 video camera and a video digitizer. The MCPII was gated on with a pulse synchronously timed to the laser pulse. The relative timing between the reflected laser pulse and the shuttering of the MCPII determined the distance to the imaged region. The resolution of the image was influenced by the MCPII`s shutter time. A comparison was made between the resolution of images obtained with 6 ns, 500 ps and 180 ps FWHM (8 ns, 750 ps and 250 ps off-to-off) shutter times. it was found that the image resolution was enhanced by using the faster shutter since the longer exposures allowed light scattered by the water to be recorded too. The presence of scattered light in the image increased the noise, thereby reducing the contrast and the resolution.

  6. Dynamic magnetic susceptibility of systems with long-range magnetic order

    SciTech Connect

    Vannette, Matthew Dano

    2009-01-01

    The utility of the TDR as an instrument in the study of magnetically ordered materials has been expanded beyond the simple demonstration purposes. Results of static applied magnetic field dependent measurements of the dynamic magnetic susceptibility, χ, of various ferromagnetic (FM) and antiferromagnetic (AFM) materials showing a range of transition temperatures (1-800 K) are presented. Data was collected primarily with a tunnel diode resonator (TDR) at different radio-frequencies (~10-30 MHz). In the vicinity of TC local moment ferromagnets show a very sharp, narrow peak in χ which is suppressed in amplitude and shifted to higher temperatures as the static bias field is increased. Unexpectedly, critical scaling analysis fails for these data. It is seen that these data are frequency dependent, however there is no simple method whereby measurement frequency can be changed in a controllable fashion. In contrast, itinerant ferromagnets show a broad maximum in χ well below TC which is suppressed and shifts to lower temperatures as the dc bias field is increased. The data on itinerant ferromagnets is fitted to a semi-phenomenological model that suggests the sample response is dominated by the uncompensated minority spins in the conduction band. Concluding remarks suggest possible scenarios to achieve frequency resolved data using the TDR as well as other fields in which the apparatus may be exploited.

  7. Regional reconstruction of flash flood history in the Guadarrama range (Central System, Spain).

    PubMed

    Rodriguez-Morata, C; Ballesteros-Cánovas, J A; Trappmann, D; Beniston, M; Stoffel, M

    2016-04-15

    Flash floods are a common natural hazard in Mediterranean mountain environments and responsible for serious economic and human disasters. The study of flash flood dynamics and their triggers is a key issue; however, the retrieval of historical data is often limited in mountain regions as a result of short time series and the systematic lack of historical data. In this study, we attempt to overcome data deficiency by supplementing existing records with dendrogeomorphic techniques which were employed in seven mountain streams along the northern slopes of the Guadarrama Mountain range. Here we present results derived from the tree-ring analysis of 117 samples from 63 Pinus sylvestris L. trees injured by flash floods, to complement existing flash flood records covering the last ~200years and comment on their hydro-meteorological triggers. To understand the varying number of reconstructed flash flood events in each of the catchments, we also performed a comparative analysis of geomorphic catchment characteristics, land use evolution and forest management. Furthermore, we discuss the limitations of dendrogeomorphic techniques applied in managed forests.

  8. Regional reconstruction of flash flood history in the Guadarrama range (Central System, Spain).

    PubMed

    Rodriguez-Morata, C; Ballesteros-Cánovas, J A; Trappmann, D; Beniston, M; Stoffel, M

    2016-04-15

    Flash floods are a common natural hazard in Mediterranean mountain environments and responsible for serious economic and human disasters. The study of flash flood dynamics and their triggers is a key issue; however, the retrieval of historical data is often limited in mountain regions as a result of short time series and the systematic lack of historical data. In this study, we attempt to overcome data deficiency by supplementing existing records with dendrogeomorphic techniques which were employed in seven mountain streams along the northern slopes of the Guadarrama Mountain range. Here we present results derived from the tree-ring analysis of 117 samples from 63 Pinus sylvestris L. trees injured by flash floods, to complement existing flash flood records covering the last ~200years and comment on their hydro-meteorological triggers. To understand the varying number of reconstructed flash flood events in each of the catchments, we also performed a comparative analysis of geomorphic catchment characteristics, land use evolution and forest management. Furthermore, we discuss the limitations of dendrogeomorphic techniques applied in managed forests. PMID:26845178

  9. Anderson transition in low-dimensional disordered systems driven by long-range nonrandom hopping.

    PubMed

    Rodríguez, A; Malyshev, V A; Sierra, G; Martín-Delgado, M A; Rodríguez-Laguna, J; Domínguez-Adame, F

    2003-01-17

    The single-parameter scaling hypothesis predicts the absence of delocalized states for noninteracting quasiparticles in low-dimensional disordered systems. We show analytically, using a supersymmetric method combined with a renormalization group analysis, as well as numerically that extended states may occur in the one- and two-dimensional Anderson model with a nonrandom hopping falling off as some power of the distance between sites. The different size scaling of the bare level spacing and the renormalized magnitude of the disorder seen by the quasiparticles finally results in the delocalization of states at one of the band edges of the quasiparticle energy spectrum.

  10. Numerical studies of variable-range hopping in one-dimensional systems

    NASA Astrophysics Data System (ADS)

    Rodin, A. S.; Fogler, M. M.

    2010-03-01

    We report on our recent numerical study [1] of hopping transport in disordered one-dimensional systems. A fast new algorithm, based on Dijkstra shortest-path algorithm, is devised to find the lowest-resistance path through the hopping network at arbitrary electric field. Probability distribution functions of individual resistances on the path and the net resistance are calculated and fitted to compact analytic formulas. Qualitative differences between statistics of resistance fluctuations in Ohmic and non-Ohmic regimes are elucidated. The results are compared with prior theoretical and experimental work on the subject.[6pt] [1] A. S. Rodin and M. M. Fogler, Phys. Rev. B 80, 155435 (2009).

  11. LANDSAT Range Resource Information System. [a user evaluation of green forage and rainfall accumulation maps

    NASA Technical Reports Server (NTRS)

    Boyd, W. E.; Harlan, J. C.

    1981-01-01

    A series of test products were developed from LANDSAT data sets for North Central Texas that paralleled the needs of ranchers, technical personnel, and the media. The products and evaluation questionnaires were mailed to approximately 150 ranchers who had reported an interest in evaluating the information systems. In addition to the rancher group, fourteen media people and a thirty-three member group in the agri business/technical community was also chosen to receive test products. The group responses are analyzed. Examples of the test products and associated questionnaires are included.

  12. Characteristic responses of biological and nanoscale systems in the terahertz frequency range

    NASA Astrophysics Data System (ADS)

    Angeluts, A. A.; Balakin, A. V.; Evdokimov, M. G.; Esaulkov, M. N.; Nazarov, M. M.; Ozheredov, I. A.; Sapozhnikov, D. A.; Solyankin, P. M.; Cherkasova, O. P.; Shkurinov, A. P.

    2014-07-01

    This paper briefly examines methods for the generation of pulsed terahertz radiation and principles of pulsed terahertz spectroscopy, an advanced informative method for studies of complex biological and nanostructured systems. Some of its practical applications are described. Using a number of steroid hormones as examples, we demonstrate that terahertz spectroscopy in combination with molecular dynamics methods and computer simulation allows one to gain information about the structure of molecules in crystals. A 'terahertz colour vision' method is proposed for analysis of pulsed terahertz signals reflected from biological tissues and it is shown that this method can be effectively used to analyse the properties of biological tissues and for early skin cancer diagnosis.

  13. Viability of the Matter Bounce Scenario

    NASA Astrophysics Data System (ADS)

    de Haro, Jaume; Amorós, Jaume

    2015-04-01

    It is shown that teleparallel F(T) theories of gravity combined with Loop Quantum Cosmology support a Matter Bounce Scenario which is an alternative to the inflation scenario in the Big Bang paradigm. It is checked that these bouncing models provide theoretical data that fits well with the current observational data, allowing the viability of the Matter Bounce Scenario.

  14. Storage and Viability of Hedychium Pollen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hedychium species generally flower in the summer and fall, but some bloom in winter and spring times. The different flowering times of the species implies that there is a need to find a way for storing and conserving viable pollen. The maintenance of pollen viability depends on several factors, incl...

  15. The Viability of "Roe v. Wade."

    ERIC Educational Resources Information Center

    Belson, Nicole

    1989-01-01

    Examines four issues involved in "Webster v. Reproductive Health Services:" (1) the preamble to the 1986 Missouri statute on abortion, (2) prohibiting public employees from performing abortions, (3) public funds for encouraging abortion, and (4) gestational age and viability provision. Focuses on the effects on the continuing vitality of the…

  16. Viability of mesenchymal stem cells during electrospinning

    PubMed Central

    Zanatta, G.; Steffens, D.; Braghirolli, D.I.; Fernandes, R.A.; Netto, C.A.; Pranke, P.

    2011-01-01

    Tissue engineering is a technique by which a live tissue can be re-constructed and one of its main goals is to associate cells with biomaterials. Electrospinning is a technique that facilitates the production of nanofibers and is commonly used to develop fibrous scaffolds to be used in tissue engineering. In the present study, a different approach for cell incorporation into fibrous scaffolds was tested. Mesenchymal stem cells were extracted from the wall of the umbilical cord and mononuclear cells from umbilical cord blood. Cells were re-suspended in a 10% polyvinyl alcohol solution and subjected to electrospinning for 30 min under a voltage of 21 kV. Cell viability was assessed before and after the procedure by exclusion of dead cells using trypan blue staining. Fiber diameter was observed by scanning electron microscopy and the presence of cells within the scaffolds was analyzed by confocal laser scanning microscopy. After electrospinning, the viability of mesenchymal stem cells was reduced from 88 to 19.6% and the viability of mononuclear cells from 99 to 8.38%. The loss of viability was possibly due to the high viscosity of the polymer solution, which reduced the access to nutrients associated with electric and mechanical stress during electrospinning. These results suggest that the incorporation of cells during fiber formation by electrospinning is a viable process that needs more investigation in order to find ways to protect cells from damage. PMID:22183245

  17. Viability of mesenchymal stem cells during electrospinning.

    PubMed

    Zanatta, G; Steffens, D; Braghirolli, D I; Fernandes, R A; Netto, C A; Pranke, P

    2012-02-01

    Tissue engineering is a technique by which a live tissue can be re-constructed and one of its main goals is to associate cells with biomaterials. Electrospinning is a technique that facilitates the production of nanofibers and is commonly used to develop fibrous scaffolds to be used in tissue engineering. In the present study, a different approach for cell incorporation into fibrous scaffolds was tested. Mesenchymal stem cells were extracted from the wall of the umbilical cord and mononuclear cells from umbilical cord blood. Cells were re-suspended in a 10% polyvinyl alcohol solution and subjected to electrospinning for 30 min under a voltage of 21 kV. Cell viability was assessed before and after the procedure by exclusion of dead cells using trypan blue staining. Fiber diameter was observed by scanning electron microscopy and the presence of cells within the scaffolds was analyzed by confocal laser scanning microscopy. After electrospinning, the viability of mesenchymal stem cells was reduced from 88 to 19.6% and the viability of mononuclear cells from 99 to 8.38%. The loss of viability was possibly due to the high viscosity of the polymer solution, which reduced the access to nutrients associated with electric and mechanical stress during electrospinning. These results suggest that the incorporation of cells during fiber formation by electrospinning is a viable process that needs more investigation in order to find ways to protect cells from damage.

  18. High dynamic range diamond detector acquisition system for beam wire scanner applications

    NASA Astrophysics Data System (ADS)

    Sirvent, J. L.; Dehning, B.; Piselli, E.; Emery, J.; Dieguez, A.

    2016-03-01

    The CERN Beam Instrumentation group has been working during the last years on the beam wire scanners upgrade to cope up with the increasing requirements of CERN experiments. These devices are used to measure the beam profile by crossing a thin wire through a circulating beam, the resulting secondary particles produced from beam/wire interaction are detected and correlated with the wire position to reconstruct the beam profile. The upgraded secondary particles acquisition electronics will use polycrystalline chemical vapour deposition (pCVD) diamond detectors for particle shower measurements, with low noise acquisitions performed on the tunnel, near the detector. The digital data is transmitted to the surface through an optical link with the GBT protocol. Two integrator ASICs (ICECAL and QIE10) are being characterized and compared for detector readout with the complete acquisition chain prototype. This contribution presents the project status, the QIE10 front-end performance and the first measurements with the complete acquisition system prototype. In addition, diamond detector signals from particle showers generated by an operational beam wire scanner are analysed and compared with an operational system.

  19. Mcps-range photon-counting x-ray computed tomography system

    NASA Astrophysics Data System (ADS)

    Sato, Eiichi; Oda, Yasuyuki; Abudurexiti, Abulajiang; Hagiwara, Osahiko; Enomoto, Toshiyuki; Sugimura, Shigeaki; Endo, Haruyuki; Sato, Shigehiro; Ogawa, Akira; Onagawa, Jun

    2011-10-01

    10 Mcps photon counting was carried out using a detector consisting of a 2.0 mm-thick ZnO (zinc oxide) single-crystal scintillator and an MPPC (multipixel photon counter) module in an X-ray computed tomography (CT) system. The maximum count rate was 10 Mcps (mega counts per second) at a tube voltage of 70 kV and a tube current of 2.0 mA. Next, a photon-counting X-ray CT system consists of an X-ray generator, a turntable, a scan stage, a two-stage controller, the ZnO-MPPC detector, a counter card (CC), and a personal computer (PC). Tomography is accomplished by repeated linear scans and rotations of an object, and projection curves of the object are obtained by the linear scan with a scan velocity of 25 mm/s. The pulses of the event signal from the module are counted by the CC in conjunction with the PC. The exposure time for obtaining a tomogram was 600 s at a scan step of 0.5 mm and a rotation step of 1.0°, and photon-counting CT was accomplished using iodine-based contrast media.

  20. Implementation of a close range photogrammetric system for 3D reconstruction of a scoliotic torso

    NASA Astrophysics Data System (ADS)

    Detchev, Ivan Denislavov

    Scoliosis is a deformity of the human spine most commonly encountered with children. After being detected, periodic examinations via x-rays are traditionally used to measure its progression. However, due to the increased risk of cancer, a non-invasive and radiation-free scoliosis detection and progression monitoring methodology is needed. Quantifying the scoliotic deformity through the torso surface is a valid alternative, because of its high correlation with the internal spine curvature. This work proposes a low-cost multi-camera photogrammetric system for semi-automated 3D reconstruction of a torso surface with sub-millimetre level accuracy. The thesis describes the system design and calibration for optimal accuracy. It also covers the methodology behind the reconstruction and registration procedures. The experimental results include the complete reconstruction of a scoliotic torso mannequin. The final accuracy is evaluated through the goodness of fit between the reconstructed surface and a more accurate set of points measured by a coordinate measuring machine.