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  1. BIOGENIC EMISSIONS INVENTORY SYSTEM (BEIS)

    EPA Science Inventory

    The Biogenic Emissions Inventory System (BEIS) is a computer algorithm used to generate emissions for air quality simulation models, such as EPAs Regional Acid Deposition Model (RADM). Emission sources that are modeled include volatile organic compound (VOC) emissions from vegeta...

  2. Strahlungsfeldbedingungen bei der Ionisationsdosimetrie

    NASA Astrophysics Data System (ADS)

    Krieger, Hanno

    Bei der Dosimetrie von Photonenstrahlungen mit luftgefüllten Ionisationskammern werden in diesem Kapitel zwei Grenzfälle unterschieden. Der eine Fall ist die Bedingung des so genannten Sekundärelektronengleichwichts im Kammervolumen. In diesem Fall bestimmen ausschließlich die Photonen im Messvolumen die dosimetrische Anzeige. Der zweite Grenzfall ist gegeben, wenn das Luftvolumen und die Kammer das Strahlungsfeld im Phantom so wenig stören, dass der Sekundärelektronenfluss unverändert bleibt. Diese Bedingungen nennt man BRAGG-GRAY-Bedingungen. Beide Grenzfälle sind in der Praxis nur näherungsweise zu verwirklichen. Abweichungen müssen durch entsprechende Korrekturen oder Kalibrierungen berücksichtigt werden.

  3. BEI Resources: Supporting antiviral research

    PubMed Central

    Baker, Robert; Peacock, Susan

    2008-01-01

    The Biodefense and Emerging Infections Research Resources Repository (BEI Resources) provides unique, quality-assured reagents to the scientific community for use in basic research and product development involving biodefense and emerging infectious diseases. These include microorganisms (up to Biosafety Level-3) on the National Institute of Allergy and Infectious Diseases (NIAID) and Centers for Disease Control and Prevention (CDC) lists of Category A, B and C priority pathogens. In addition to live microorganisms, related products such as polyclonal antisera, monoclonal antibodies, isolated nucleic acid preparations, overlapping peptide arrays, purified proteins, and assay kits are also available. Many of these materials have direct or indirect applications in antiviral research. These reagents are available free of charge to all registered investigators, regardless of funding source or affiliation. Acquisition of new reagents for the repository is one of the critically necessary and challenging tasks for BEI Resources. Therefore, investigators are encouraged to deposit relevant items, so as to provide access to materials, relief from the burden of distribution, protection of intellectual property rights, and secure storage. In addition, BEI Resources has the capability of contracting for the preparation of specific reagents. If there is a resource needed to advance a specific research area, contact an NIAID program officer or use the “suggest a reagent” option on the BEI Resources homepage, www.beiresources.org. PMID:18675849

  4. Cation-Cation Interactions in [(UO2)2(OH)n](4-n) Complexes

    SciTech Connect

    Odoh, Samuel O.; Govind, Niranjan; Schreckenbach, Georg; De Jong, Wibe A.

    2013-10-07

    The structures and bonding of gas-phase [(UO2)2(OH)n]4-n (n=2-6) complexes have been studied using density functional theory (DFT), MP2 and CCSD(T) methods with particular emphasis on ground state structures featuring cation-cation interactions (CCIs) between the uranyl groups. An interesting trend is observed in the stabilities of members of this series of complexes. The structures of [(UO2)2(OH)2]2+, [(UO2)2(OH)4] and [(UO2)2(OH)6]2- featuring CCIs are found at higher energies (by 3-20 kcal/mol) in comparison to their conventional μ2-dihydroxo structures. In contrast, the CCI structures of [(UO2)2(OH)3]+ and [(UO2)2(OH)5]- are respectively almost degenerate with and lower in energy than the structures with the μ2-dihydroxo format. The origin of this trend lies in the ‘symmetry’-based need to balance the coordination numbers and effective atomic charges of each uranium center. The calculated IR vibrational frequencies provide signature probes that can be used in differentiating the lowenergy structures and in experimentally confirming the existence of the structures featuring CCIs. Analysis of the bonding in the structures of [(UO2)2(OH)3]+ and [(UO2)2(OH)5]- shows that the CCIs and bridging hydroxo between the dioxo-uranium units are mainly electrostatic in nature.

  5. Signale ohne Antwort? Die Suche nach außerirdischem Leben.

    NASA Astrophysics Data System (ADS)

    Davoust, E.

    This book is a German translation, by M. Röser, of the English version "The cosmic water hole", published in 1991 (see 53.003.080). The original French edition "Silence au point d'eau" was published in 1988 (see 45.003.059). Contents: I. Leben auf der Erde. 1. Kometen und der Ursprung des Lebens. 2. Die zeitliche Dimension des Lebens. 3. Evolution und Katastrophen. 4. Liegt unsere Zukunft im Weltall? II. Leben im Universum. 5. Die Suche nach Leben in der Sonnenumgebung. 6. Die Suche nach Planetensystemen. III. Intelligentes Leben im Universum. 7. Demographie außerirdischer Zivilisationen. 8. Soziologie außerirdischer Zivilisationen. 9. UFO's und Besuche in der Vergangenheit. 10. Strategien bei der Suche nach außerirdischen Zivilisationen. 11. Die Suche nach künstlichen Signalen. 12. Die Diskussion innerhalb der Gesellschaft. 13. Die Stellung des Menschen im Universum.

  6. The BEI hydrolysis process and reactor system refined engineering proto-type. BEI pilot-plant improvement and operations demonstrations

    SciTech Connect

    Brelsford, Donald L.

    1999-10-01

    This BEI project involves BEI-HP and RS's applications toward potential commercial validity demonstrations for dilute-acid corn-fiber cellulose-hydrolysis processing with an aim toward fuel ethanol production.

  7. Simultaneous UV- and ion processing of astrophysically relevant ices. The case of CH3OH:N2 solid mixtures

    NASA Astrophysics Data System (ADS)

    Islam, F.; Baratta, G. A.; Palumbo, M. E.

    2014-01-01

    Context. Interstellar ices are known to be simultaneously processed by both cosmic-ray bombardment and UV photolysis. Our knowledge of the effects of energetic processing on relevant icy samples is mainly based on laboratory investigations. In the past 35 years many experiments have been performed to study these effects separately but, to the best of our knowledge, never simultaneously. Aims: The aim of this work is to study the effects of simultaneous processing of ices by both cosmic rays and UV photons to investigate to what extent the combined effect of ion bombardment and UV photolysis influences the chemical pathways. Methods: We carried out the simultaneous processing of CH3OH:N2 ice held at 16 K by 200 keV H+ ions and Lyman-alpha 10.2 eV UV photons. The samples were analyzed by in situ transmission infrared spectroscopy. The un-combined processes of UV irradiation and bombardment by H+ ions of CH3OH:N2 ice were also studied. This mixture was chosen because the effects of ion bombardment and UV photolysis on methanol and nitrogen have been extensively studied in previous investigations. This mixture enables one to investigate whether simultaneous processing (a) influences the destruction of original species; (b) influences the formation of new species; or (c) causes synergistic effects since Lyman-alpha photons have a very low efficiency in breaking the dinitrogen bond because N2 is almost transparent at Lyman-alpha wavelengths. Results: After processing a CH3OH:N2 sample, the intensity of the methanol bands was observed to decrease at the same rate in all cases. After ion bombardment, species such as CO2, CO, H2CO, CH4, N2O, HNCO, and OCN- are formed in the ice mixture. After UV photolysis, species such as CO2, CO, H2CO, and CH4 are formed, but no N-bearing species are detected. Spectra of ices processed by both UV photons and ions were compared with spectra of ices bombarded only by ions. We find that there are no differences in the band area and profile

  8. Overcoming the challenges of BeiDou receiver implementation.

    PubMed

    Bhuiyan, Mohammad Zahidul H; Söderholm, Stefan; Thombre, Sarang; Ruotsalainen, Laura; Kuusniemi, Heidi

    2014-01-01

    Global Navigation Satellite System (GNSS)-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS) and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning. PMID:25421735

  9. Overcoming the Challenges of BeiDou Receiver Implementation

    PubMed Central

    Bhuiyan, Mohammad Zahidul H.; Söderholm, Stefan; Thombre, Sarang; Ruotsalainen, Laura; Kuusniemi, Heidi

    2014-01-01

    Global Navigation Satellite System (GNSS)-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS) and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning. PMID:25421735

  10. Precise Point Positioning with the BeiDou Navigation Satellite System

    PubMed Central

    Li, Min; Qu, Lizhong; Zhao, Qile; Guo, Jing; Su, Xing; Li, Xiaotao

    2014-01-01

    By the end of 2012, China had launched 16 BeiDou-2 navigation satellites that include six GEOs, five IGSOs and five MEOs. This has provided initial navigation and precise pointing services ability in the Asia-Pacific regions. In order to assess the navigation and positioning performance of the BeiDou-2 system, Wuhan University has built up a network of BeiDou Experimental Tracking Stations (BETS) around the World. The Position and Navigation Data Analyst (PANDA) software was modified to determine the orbits of BeiDou satellites and provide precise orbit and satellite clock bias products from the BeiDou satellite system for user applications. This article uses the BeiDou/GPS observations of the BeiDou Experimental Tracking Stations to realize the BeiDou and BeiDou/GPS static and kinematic precise point positioning (PPP). The result indicates that the precision of BeiDou static and kinematic PPP reaches centimeter level. The precision of BeiDou/GPS kinematic PPP solutions is improved significantly compared to that of BeiDou-only or GPS-only kinematic PPP solutions. The PPP convergence time also decreases with the use of combined BeiDou/GPS systems. PMID:24406856

  11. Instantaneous BeiDou-GPS attitude determination: A performance analysis

    NASA Astrophysics Data System (ADS)

    Nadarajah, Nandakumaran; Teunissen, Peter J. G.; Raziq, Noor

    2014-09-01

    The advent of modernized and new global navigation satellite systems (GNSS) has enhanced the availability of satellite based positioning, navigation, and timing (PNT) solutions. Specifically, it increases redundancy and yields operational back-up or independence in case of failure or unavailability of one system. Among existing GNSS, the Chinese BeiDou system (BDS) is being developed and will consist of geostationary (GEO) satellites, inclined geosynchronous orbit (IGSO) satellites, and medium-Earth-orbit (MEO) satellites. In this contribution, a BeiDou-GPS robustness analysis is carried out for instantaneous, unaided attitude determination. Precise attitude determination using multiple GNSS antennas mounted on a platform relies on the successful resolution of the integer carrier phase ambiguities. The constrained Least-squares AMBiguity Decorrelation Adjustment (C-LAMBDA) method has been developed for the quadratically constrained GNSS compass model that incorporates the known baseline length. In this contribution the method is used to analyse the attitude determination performance when using the GPS and BeiDou systems. The attitude determination performance is evaluated using GPS/BeiDou data sets from a real data campaign in Australia spanning several days. The study includes the performance analyses of both stand-alone and mixed constellation (GPS/BeiDou) attitude estimation under various satellite deprived environments. We demonstrate and quantify the improved availability and accuracy of attitude determination using the combined constellation.

  12. Development and Evaluation of the Biogenic Emissions Inventory System (BEIS) Model v3.6

    EPA Science Inventory

    We have developed new canopy emission algorithms and land use data for BEIS v3.6. Simulations with BEIS v3.4 and BEIS v3.6 in CMAQ v5.0.2 are compared these changes to the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and evaluated the simulations against observati...

  13. BeiDou Time Transfer With the Standard CGGTTS.

    PubMed

    Huang, Wei; Defraigne, Pascale

    2016-07-01

    The R2CGGTTS software tool developed at the Royal Observatory of Belgium (ROB) to provide clock solutions in the standard Common GNSS Generic Time Transfer Standard (CGGTTS) has been extended to BeiDou Navigation Satellite System (BDS). The BDS includes satellites in three different orbits: 1) Medium Earth Orbit (MEO); 2) Inclined Geosynchronous Satellite Orbit (IGSO); and 3) Geostationary Earth Orbit (GEO). This paper presents first results obtained with this upgraded software, and a comparison between common view (CV) time transfer solutions obtained with either BDS, or GPS or Galileo. These preliminary results indicate that the BeiDou MEO satellites give time transfer results with a higher noise than the GPS results. This additional noise is shown to be due to some elevation-dependent delay in the BDS code measurements. Some biases were furthermore pointed out between the CV results obtained with the different BeiDou MEO satellites when the receivers used in the two stations are of different make. These biases may reach some nanoseconds, and find most probably their origin in the receiver hardware or firmware. It is shown additionally that using the BeiDou IGSO satellites and the GEO satellites, although increasing the number of observations, especially in the Asia-Pacific region, introduces a significant time transfer noise in the CV results. PMID:26766373

  14. Teaching Pablo Neruda and Bei Dao: The Lens of Leaving.

    ERIC Educational Resources Information Center

    Lichtenstein, Amanda Leigh

    2003-01-01

    Explains how the author invites young poets to tromp through the landscape of their minds in search of all things broken by using two of her favorite poems: Pablo Neruda's "Ode to Broken Things" and Bei Dao's "Comet." Outlines how the students write their own poems dealing with loss. Notes that for poets, a heap of broken images becomes an immense…

  15. Epigenetische Aspekte bei Karzinomen der Kopf-Hals-Region

    PubMed Central

    Schmezer, Peter; Plass, Christoph

    2009-01-01

    Zusammenfassung Plattenepithelkarzinome der Kopf-Hals-Region (HNSCC) zählen seit Jahren zu den weltweit häufigsten Krebsarten. Trotz vieler Bemühungen hat sich das 5-Jahres-Überleben bei Patienten mit HNSCC kaum verbessert. Um einen Fortschritt zu erzielen, ist es notwendig, die der Erkrankung zugrunde liegenden biologischen Prozesse besser zu verstehen. Neben den bekannten genetischen Veränderungen haben molekular-zytogenetische Untersuchungen bei HNSCC gezeigt, dass es weitere Veränderungen gibt, die mit Vermehrung und Verlust chromosomaler Bereiche einhergehen, für die jedoch die krankheitsverursachenden Gene bisher nicht identifiziert wurden. Darüberhinaus haben jüngste Forschungsergebnisse verdeutlicht, dass epigenetische Modifikationen wie die DNA Methylierung eine wichtige Rolle spielen. So konnte gezeigt werden, dass bei HNSCC eine Reihe von Genen (z.B. das Tumorsuppressorgen CDKN2A sowie DAPK1, MGMT, TIMP3, TCF21, und C/EBPα) hypermethylierte Bereiche in regulatorischen DNA Sequenzen aufweisen, wodurch ihre Expression verringert oder unterbunden wird. Die Hypermethylierung solcher Gene könnte als Biomarker zur Früherkennung von HNSCC genutzt werden und nicht zuletzt dadurch zur Verbesserung von Prävention und Therapieerfolg beitragen. PMID:18483718

  16. Precise Orbit Determination of BeiDou Navigation Satellite System

    NASA Astrophysics Data System (ADS)

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-04-01

    China has been developing its own independent satellite navigation system since decades. Now the COMPASS system, also known as BeiDou, is emerging and gaining more and more interest and attention in the worldwide GNSS communities. The current regional BeiDou system is ready for its operational service around the end of 2012 with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit satellites (IGSO) and four Medium Earth orbit (MEO) satellites in operation. Besides the open service with positioning accuracy of around 10m which is free to civilian users, both precise relative positioning, and precise point positioning are demonstrated as well. In order to enhance the BeiDou precise positioning service, Precise Orbit Determination (POD) which is essential of any satellite navigation system has been investigated and studied thoroughly. To further improving the orbits of different types of satellites, we study the impact of network coverage on POD data products by comparing results from tracking networks over the Chinese territory, Asian-Pacific, Asian and of global scale. Furthermore, we concentrate on the improvement of involving MEOs on the orbit quality of GEOs and IGSOs. POD with and without MEOs are undertaken and results are analyzed. Finally, integer ambiguity resolution which brings highly improvement on orbits and positions with GPS data is also carried out and its effect on POD data products is assessed and discussed in detail. Seven weeks of BeiDou data from a ground tracking network, deployed by Wuhan University is employed in this study. The test constellation includes four GEO, five IGSO and two MEO satellites in operation. The three-day solution approach is employed to enhance its strength due to the limited coverage of the tracking network and the small movement of most of the satellites. A number of tracking scenarios and processing schemas are identified and processed and overlapping orbit

  17. USER'S GUIDE TO THE PERSONAL COMPUTER VERSION OF THE BIOGENIC EMISSIONS INVENTORY SYSTEM (PC-BEIS)

    EPA Science Inventory

    The Personal Computer Version of the Biogenic Emissions Inventory System (PC-BEIS) has been developed to allow users to estimate hourly emissions of biogenic non-methane hydrocarbon emissions for any county in the contiguous United States. PC-BEIS has been compiled using Microsof...

  18. "Updates to Model Algorithms & Inputs for the Biogenic Emissions Inventory System (BEIS) Model"

    EPA Science Inventory

    We have developed new canopy emission algorithms and land use data for BEIS. Simulations with BEIS v3.4 and these updates in CMAQ v5.0.2 are compared these changes to the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and evaluated the simulations against observatio...

  19. An intercomparison of biogenic emissions estimates from BEIS2 and BIOME: Reconciling the differences

    SciTech Connect

    Wilkinson, J.G.; Emigh, R.A.; Pierce, T.E.

    1996-12-31

    Biogenic emissions play a critical role in urban and regional air quality. For instance, biogenic emissions contribute upwards of 76% of the daily hydrocarbon emissions in the Atlanta, Georgia airshed. The Biogenic Emissions Inventory System-Version 2.0 (BEIS2) and the Biogenic Model for Emissions (BIOME) are two models that compute biogenic emissions estimates. BEIS2 is a FORTRAN-based system, and BIOME is an ARC/INFO{reg_sign} - and SAS{reg_sign}-based system. Although the technical formulations of the models are similar, the models produce different biogenic emissions estimates for what appear to be essentially the same inputs. The goals of our study are the following: (1) Determine why BIOME and BEIS2 produce different emissions estimates; (2) Attempt to understand the impacts that the differences have on the emissions estimates; (3) Reconcile the differences where possible; and (4) Present a framework for the use of BEIS2 and BIOME. In this study, we used the Coastal Oxidant Assessment for Southeast Texas (COAST) biogenics data which were supplied to us courtesy of the Texas Natural Resource Conservation Commission (TNRCC), and we extracted the BEIS2 data for the same domain. We compared the emissions estimates of the two models using their respective data sets BIOME Using TNRCC data and BEIS2 using BEIS2 data.

  20. Berechnung verkehrlicher Substitutionseffekte im Personenverkehr bei Online-Shopping

    NASA Astrophysics Data System (ADS)

    Nerlich, Mark R.; Schiffner, Felix; Vogt, Walter; Rauh, Jürgen; Breidenbach, Petra

    Für Güter des täglichen, mittelfristigen und langfristigen Bedarfs sowie für das Beispiel Baumarktartikel wird das Potenzial für Personenverkehrsaufwand von Einkaufsaktivtäten quantitativ abgeschätzt. Die entwickelten Algorithmen behandeln die einkaufsvorbereitende Information und den eigentlichen Einkauf, d.h. den Erwerb eines Gutes, separat. Informationsaktivitäten haben insbesondere bei höherwertigen Gütern einen hohen Stellenwert und damit auch verkehrliche Relevanz. Wie Berechnungen zeigen, spart Online-Shopping Informations- und Einkaufsverkehrsaufwand im Pkw-Verkehr ein. Die notwendigen Eingangsdaten wie differenzierte Informations- und Einkaufshäufigkeiten sowie verkehrliche Parameter zu Verkehrsmittelwahl, Entfernungen und Wegekopplungen wurden aus eigenen Erhebungen gewonnen.

  1. Cyber-Physical Systems - Wissenschaftliche Herausforderungen Bei Der Entwicklung

    NASA Astrophysics Data System (ADS)

    Broy, Manfred

    Cyber-Physical Systems adressieren die enge Verbindung eingebetteter Systeme zur Überwachung und Steuerung physikalischer Vorgänge mittels Sensoren und Aktuatoren über Kommunikationseinrichtungen mit den globalen digitalen Netzen (dem Cyberspace"). Dieser Typus von Systemen ermöglicht über Wirkketten eine Verbindung zwischen Vorgängen der physischen Realität und den heute verfügbaren digitalen Netzinfrastrukturen. Dies erlaubt vielfältige Applikationen mit hohem wirtschaftlichen Potential, und mit starker Innovationskraft. Die vollständige Ausschöpfung des Potentials erfordert aber gezielte wissenschaftliche Anstrengungen bei der Entwicklung solcher Systeme im Hinblick auf Methodik, Technologie, Kostenbeherrschung und funktionale Angemessenheit.

  2. Estimation of Satellite PCO Offsets for BeiDou based on MGEX Net Solution

    NASA Astrophysics Data System (ADS)

    Yize, Zhang; Junping, Chen; Bin, Wu; Jiexian, Wang

    2015-04-01

    BeiDou Satellite Navigation System currently has a total 14 satellites including GEO/IGSO/MEO satellites and providing a regional PNT service. Due to a lack of publicly available antenna phase center offsets (PCO) for the BeiDou satellites, conventional values of (+0.6 m, 0.0 m, +1.1 m) are recommended for orbit and clock determination of the GEO/IGSO/MEO satellites, which needs to be further estimation and refinement. In this paper, we propose a multi-GNSS network solution for the estimation of BeiDou satellite PCO. More than 35 ground stations of International GNSS MGEX tracking network are used to determine the BeiDou satellite PCO. In this strategy, the GPS and BeiDou satellite orbits and clocks are derived from IGS final products, and GPS satellite PCO and PCV are fixed according to igs08.atx. The BeiDou satellites PCO are estimated together with the station clock, troposphere delay and LC combination ambiguity parameter. Result shows that the RMS of phase residuals for all stations is 1.8cm and is 1.6m for code residual, respectively. The estimated PCO is different for each satellite. Appling the new PCO for precise point positioning, we found that the positioning error improves from 6cm to 2cm in height.

  3. BeiDou inter-satellite-type bias evaluation and calibration for mixed receiver attitude determination.

    PubMed

    Nadarajah, Nandakumaran; Teunissen, Peter J G; Raziq, Noor

    2013-01-01

    The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium Earth Orbit (MEO) satellites. This paper investigates the receiver-dependent bias between these satellite types, for which we coined the name "inter-satellite-type bias" (ISTB), and its impact on mixed receiver attitude determination. Assuming different receiver types may have different delays/biases for different satellite types, we model the differential ISTBs among three BeiDou satellite types and investigate their existence and their impact on mixed receiver attitude determination. Our analyses using the real data sets from Curtin's GNSS array consisting of different types of BeiDou enabled receivers and series of zero-baseline experiments with BeiDou-enabled receivers reveal the existence of non-zero ISTBs between different BeiDou satellite types. We then analyse the impact of these biases on BeiDou-only attitude determination using the constrained (C-)LAMBDA method, which exploits the knowledge of baseline length. Results demonstrate that these biases could seriously affect the integer ambiguity resolution for attitude determination using mixed receiver types and that a priori correction of these biases will dramatically improve the success rate. PMID:23881141

  4. BeiDou Inter-Satellite-Type Bias Evaluation and Calibration for Mixed Receiver Attitude Determination

    PubMed Central

    Nadarajah, Nandakumaran; Teunissen, Peter J. G.; Raziq, Noor

    2013-01-01

    The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium Earth Orbit (MEO) satellites. This paper investigates the receiver-dependent bias between these satellite types, for which we coined the name “inter-satellite-type bias” (ISTB), and its impact on mixed receiver attitude determination. Assuming different receiver types may have different delays/biases for different satellite types, we model the differential ISTBs among three BeiDou satellite types and investigate their existence and their impact on mixed receiver attitude determination. Our analyses using the real data sets from Curtin's GNSS array consisting of different types of BeiDou enabled receivers and series of zero-baseline experiments with BeiDou-enabled receivers reveal the existence of non-zero ISTBs between different BeiDou satellite types. We then analyse the impact of these biases on BeiDou-only attitude determination using the constrained (C-)LAMBDA method, which exploits the knowledge of baseline length. Results demonstrate that these biases could seriously affect the integer ambiguity resolution for attitude determination using mixed receiver types and that a priori correction of these biases will dramatically improve the success rate. PMID:23881141

  5. Precise orbit determination of BeiDou constellation based on BETS and MGEX network

    PubMed Central

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-01-01

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved. PMID:24733025

  6. Precise orbit determination of BeiDou constellation based on BETS and MGEX network.

    PubMed

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-01-01

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved. PMID:24733025

  7. Precise orbit determination of BeiDou constellation based on BETS and MGEX network

    NASA Astrophysics Data System (ADS)

    Lou, Yidong; Liu, Yang; Shi, Chuang; Yao, Xiuguang; Zheng, Fu

    2014-04-01

    Chinese BeiDou Navigation Satellite System is officially operational as a regional constellation with five Geostationary Earth Orbit (GEO) satellites, five Inclined Geosynchronous Satellite Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Observations from the BeiDou Experimental Tracking Stations (BETS) and the IGS Multi-GNSS Experiment (MGEX) network from 1 January to 31 March 2013 are processed for orbit determination of the BeiDou constellation. Various arc lengths and solar radiation pressure parameters are investigated. The reduced set of ECOM five-parameter model produces better performance than the full set of ECOM nine-parameter model for BeiDou IGSO and MEO. The orbit overlap for the middle days of 3-day arc solutions is better than 20 cm and 14 cm for IGSO and MEO in RMS, respectively. Satellite laser ranging residuals are better than 10 cm for both IGSO and MEO. For BeiDou GEO, the orbit overlap of several meters and satellite laser ranging residuals of several decimetres can be achieved.

  8. Effekt einer ad libitum verzehrten fettreduzierten Kost, reich an Obst, Gemüse und Milchprodukten auf den Blutdruck bei Borderline-Hypertonikern

    NASA Astrophysics Data System (ADS)

    Möseneder, Jutta M.

    2002-01-01

    In der randomisierten, multizentrischen DASH-Studie (Dietary Approaches to Stop Hy-pertension), die unter kontrollierten Bedingungen stattfand, führte eine fettreduzierte Mischkost, reich an Obst, Gemüse und Milchprodukten, bei Borderline-Hypertonikern zu einer signifikanten Blutdrucksenkung. Während der Studienphase wurden Körpermasse, Natrium-Aufnahme sowie Alkoholzufuhr aufgrund der bekannten Einflussnahme auf den Blutdruck konstant gehalten. In der eigenen Pilot-Studie sollte untersucht werden, ob das Ergebnis der DASH-Studie (i) mit deutschen Hypertonikern und (ii) unter habituellen Ernährungs- und Lebensbedingungen mit regelmäßig durchgeführter Ernährungsberatung und ad libitum Verzehr anstelle des streng kontrollierten Studienansatzes bestätigt werden kann. Eine Konstanz der Körpermasse, der Natrium-Urinausscheidung (unter diesem Studienansatz valider als die Aufnahme) und des Alkoholkonsums wurde vorausgesetzt. Die Studienpopulation setzte sich aus 53 übergewichtigen Probanden mit einer nicht medikamentös therapierten Borderline-Hypertonie und ohne Stoffwechselerkrankungen zusammen. Die Studienteilnehmer wurden randomisiert entweder der Idealgruppe mit einer fettarmen Kost reich an Milchprodukten, Obst und Gemüse (ähnlich der DASH-Idealgruppe) oder der Kontrollgruppe mit habitueller Ernährungsweise zugeteilt. Über einen Zeitraum von fünf Wochen wurde den Probanden etwa 50% ihres täglichen Lebensmittelbedarfes entsprechend ihrer Gruppenzugehörigkeit kostenfrei zur Verfügung gestellt. Gelegenheitsblutdruckmessungen und 24h-Blutdruckmessungen, Ernährungs- und Aktivitätsprotokolle, Blut- und Urinproben sowie anthropometrische Messungen wurden vor, während und fünf Wochen nach der Interventionsphase durchgeführt. Die Ergebnisse zeigen, dass in der Idealgruppe keine signifikante Blutdrucksenkung beobachtet werden konnte. Dies lässt sich durch die Tatsache erklären, dass die Lebens-mittel- und Nährstoffaufnahme der deutschen

  9. Effekt einer ad libitum verzehrten fettreduzierten Kost, reich an Obst, Gemüse und Milchprodukten auf den Blutdruck bei Borderline-Hypertonikern

    NASA Astrophysics Data System (ADS)

    Möseneder, Jutta M.

    2002-01-01

    In der randomisierten, multizentrischen DASH-Studie (Dietary Approaches to Stop Hy-pertension), die unter kontrollierten Bedingungen stattfand, führte eine fettreduzierte Mischkost, reich an Obst, Gemüse und Milchprodukten, bei Borderline-Hypertonikern zu einer signifikanten Blutdrucksenkung. Während der Studienphase wurden Körpermasse, Natrium-Aufnahme sowie Alkoholzufuhr aufgrund der bekannten Einflussnahme auf den Blutdruck konstant gehalten. In der eigenen Pilot-Studie sollte untersucht werden, ob das Ergebnis der DASH-Studie (i) mit deutschen Hypertonikern und (ii) unter habituellen Ernährungs- und Lebensbedingungen mit regelmäßig durchgeführter Ernährungsberatung und ad libitum Verzehr anstelle des streng kontrollierten Studienansatzes bestätigt werden kann. Eine Konstanz der Körpermasse, der Natrium-Urinausscheidung (unter diesem Studienansatz valider als die Aufnahme) und des Alkoholkonsums wurde vorausgesetzt. Die Studienpopulation setzte sich aus 53 übergewichtigen Probanden mit einer nicht medikamentös therapierten Borderline-Hypertonie und ohne Stoffwechselerkrankungen zusammen. Die Studienteilnehmer wurden randomisiert entweder der Idealgruppe mit einer fettarmen Kost reich an Milchprodukten, Obst und Gemüse (ähnlich der DASH-Idealgruppe) oder der Kontrollgruppe mit habitueller Ernährungsweise zugeteilt. Über einen Zeitraum von fünf Wochen wurde den Probanden etwa 50% ihres täglichen Lebensmittelbedarfes entsprechend ihrer Gruppenzugehörigkeit kostenfrei zur Verfügung gestellt. Gelegenheitsblutdruckmessungen und 24h-Blutdruckmessungen, Ernährungs- und Aktivitätsprotokolle, Blut- und Urinproben sowie anthropometrische Messungen wurden vor, während und fünf Wochen nach der Interventionsphase durchgeführt. Die Ergebnisse zeigen, dass in der Idealgruppe keine signifikante Blutdrucksenkung beobachtet werden konnte. Dies lässt sich durch die Tatsache erklären, dass die Lebens-mittel- und Nährstoffaufnahme der deutschen

  10. CHANGES TO THE BIOGENIC EMISSION INVENTORY SYSTEM VERSION 3 (BEIS3)

    EPA Science Inventory

    This extended abstract describes recent changes to the Biogenic Emissions Inventory System (BEIS3) that were completed in preparation for the 2005 release of the Community Multiscale Air Quality model. Changes to the model affect the calculated emissions of isoprene and monoterp...

  11. Development and Evaluation of the Biogenic Emissions Inventory System (BEIS) Model v3.5

    NASA Astrophysics Data System (ADS)

    Bash, J. O.; Baker, K. R.; Pouliot, G.

    2014-12-01

    Atmospheric biogenic volatile organic compounds (BVOC) influences ozone and organic aerosol formation and can enhance the impact that anthropogenic pollutants have on ambient air-quality and climate. BVOC emissions are estimated to be approximately an order of magnitude higher than anthropogenic sources of volatile organic compounds. Despite the importance of BVOC emissions on air-quality and climate, considerable uncertainty remains in the parametrization emission algorithms and emission factors from different land uses and vegetation species. We will present three updates to the the BEIS model. (1) The BEIS canopy model has been updated with explicit estimates of leaf temperature coupled to the driving meteorological model's energy balance implemented in. (2) The Biogenic Emission Landuse Database (BELD) was updated with year specific satellite derrived land use, U.S. Department of Agriculture (USDA) crop survey data, and U.S. Forest Service forest Forest Inventory Analyssis (FIA) survayed tree speceis to develop a tree species specific land use data set. (3) A survey of published flux measurements were used to update the BEIS BVOC normalized emission factors. Incremental updates to the BEIS model are evaluated against surface and aircraft based field campain measurements and network observations in Community Multiscale Air Quality (CMAQ) model v5.0.2 simulations. Prelimilar model simulations result in improvements in model O3, isoprene, oxidized nitrogen, and aerosol performance over the contenental U.S.

  12. Precise point positioning with quad-constellations: GPS, BeiDou, GLONASS and Galileo

    NASA Astrophysics Data System (ADS)

    Cai, Changsheng; Gao, Yang; Pan, Lin; Zhu, Jianjun

    2015-07-01

    Multi-constellation GNSS precise point positioning (PPP) first became feasible back to 2007 but with only two constellations, namely GPS and GLONASS. With the availability of more satellites and precise orbit and clock products from BeiDou and Galileo, it is possible now to investigate PPP with four constellations, namely GPS, BeiDou, GLONASS and Galileo. This research aims at investigating the quad-constellation PPP for position determination and analyzing its positioning performance. A quad-constellation PPP model is developed to simultaneously process the observations from all the four GNSS systems. The developed model is also applicable to the PPP processing with observations from single, dual or triple constellations. The analysis on PPP accuracy and convergence time is conducted based on data processing results from both static and kinematic tests of single-constellation and multi-constellations. The three-hour static positioning results indicate that the BeiDou-only PPP accuracy is worse than the GPS-only PPP. The RMSs of position errors for BeiDou-only PPP are 5.2 cm, 2.7 cm and 8.3 cm in east, north and up directions while the ones for GPS-only PPP are 3.9 cm, 1.6 cm and 5.7 cm. The GPS/BeiDou PPP improves the positioning accuracy by 28%, 6% and 7% and reduces the convergence time by 26%, 13% and 14% over the GPS-only PPP in three coordinate components, respectively. The GPS/GLONASS PPP achieves slightly better performance than the GPS/BeiDou PPP. The triple-constellation PPP further increases the positioning accuracy and decreases the convergence time over the dual-constellation PPP. The improvement of positioning performance is not significant after adding Galileo due to currently limited number of satellites. Similar to the static positioning, the quad-constellation kinematic PPP also significantly improves the positioning performance in contrast with single-constellation and dual-constellations. The time varying characteristics of the time differences

  13. Stochastic modeling of triple-frequency BeiDou signals: estimation, assessment and impact analysis

    NASA Astrophysics Data System (ADS)

    Li, Bofeng

    2016-07-01

    Stochastic models are important in global navigation satellite systems (GNSS) estimation problems. One can achieve reliable ambiguity resolution and precise positioning only by use of a suitable stochastic model. The BeiDou system has received increased research focus, but based only on empirical stochastic models from the knowledge of GPS. In this paper, we will systematically study the estimation, assessment and impacts of a triple-frequency BeiDou stochastic model. In our estimation problem, a single-difference, geometry-free functional model is used to extract pure random noise. A very sophisticated structure of unknown variance matrix is designed to allow the estimation of satellite-specific variances, cross correlations between two arbitrary frequencies, as well as the time correlations for phase and code observations per frequency. In assessing the stochastic models, six data sets with four brands of BeiDou receivers on short and zero-length baselines are processed, and the results are compared. In impact analysis of stochastic model, the performance of integer ambiguity resolution and positioning are numerically demonstrated using a realistic stochastic model. The results from ultrashort (shorter than 10 m) and zero-length baselines indicate that BeiDou stochastic models are affected by both observation and receiver brands. The observation variances have been modeled by an elevation-dependent function, but the modeling errors for geostationary earth orbit (GEO) satellites are larger than for inclined geosynchronous satellite orbit (IGSO) and medium earth orbit (MEO) satellites. The stochastic model is governed by both the internal errors of the receiver and external errors at the site. Different receivers have different capabilities for resisting external errors. A realistic stochastic model is very important for achieving ambiguity resolution with a high success rate and small false alarm and for determining realistic variances for position estimates. To

  14. Stochastic modeling of triple-frequency BeiDou signals: estimation, assessment and impact analysis

    NASA Astrophysics Data System (ADS)

    Li, Bofeng

    2016-03-01

    Stochastic models are important in global navigation satellite systems (GNSS) estimation problems. One can achieve reliable ambiguity resolution and precise positioning only by use of a suitable stochastic model. The BeiDou system has received increased research focus, but based only on empirical stochastic models from the knowledge of GPS. In this paper, we will systematically study the estimation, assessment and impacts of a triple-frequency BeiDou stochastic model. In our estimation problem, a single-difference, geometry-free functional model is used to extract pure random noise. A very sophisticated structure of unknown variance matrix is designed to allow the estimation of satellite-specific variances, cross correlations between two arbitrary frequencies, as well as the time correlations for phase and code observations per frequency. In assessing the stochastic models, six data sets with four brands of BeiDou receivers on short and zero-length baselines are processed, and the results are compared. In impact analysis of stochastic model, the performance of integer ambiguity resolution and positioning are numerically demonstrated using a realistic stochastic model. The results from ultrashort (shorter than 10 m) and zero-length baselines indicate that BeiDou stochastic models are affected by both observation and receiver brands. The observation variances have been modeled by an elevation-dependent function, but the modeling errors for geostationary earth orbit (GEO) satellites are larger than for inclined geosynchronous satellite orbit (IGSO) and medium earth orbit (MEO) satellites. The stochastic model is governed by both the internal errors of the receiver and external errors at the site. Different receivers have different capabilities for resisting external errors. A realistic stochastic model is very important for achieving ambiguity resolution with a high success rate and small false alarm and for determining realistic variances for position estimates. To

  15. Sensitivity Enhancement of Bead-based Electrochemical Impedance Spectroscopy (BEIS) biosensor by electric field-focusing in microwells.

    PubMed

    Shin, Kyeong-Sik; Ji, Jae Hoon; Hwang, Kyo Seon; Jun, Seong Chan; Kang, Ji Yoon

    2016-11-15

    This paper reports a novel electrochemical impedance spectroscopy (EIS) biosensors that uses magnetic beads trapped in a microwell array to improve the sensitivity of conventional bead-based EIS (BEIS) biosensors. Unloading the previously measured beads by removing the magnetic bar enables the BEIS sensor to be used repeatedly by reloading it with new beads. Despite its recyclability, the sensitivity of conventional BEIS biosensors is so low that it has not attracted much attentions from the biosensor industry. We significantly improved the sensitivity of the BEIS system by introducing of a microwell array that contains two electrodes (a working electrode and a counter electrode) to concentrate the electric field on the surfaces of the beads. We confirmed that the performance of the BEIS sensor in a microwell array using an immunoassay of prostate specific antigen (PSA) in PBS buffer and human plasma. The experimental results showed that a low concentration of PSA (a few tens or hundreds of fg/mL) were detectable as a ratio of the changes in the impedance of the PBS buffer or in human plasma. Therefore, our BEIS sensor with a microwell array could be a promising platform for low cost, high-performance biosensors for applications that require high sensitivity and recyclability. PMID:27152445

  16. Netz ohne doppelten Boden: Internet-Sicherheit

    NASA Astrophysics Data System (ADS)

    Fichtner, Johann

    2002-07-01

    Die Sicherheitslücken des heutigen Internets haben zwei Ursachen: sein ursprüngliches Design für rein militärische Zwecke sowie die gefährliche Sorglosigkeit der Entwickler und Betreiber von Internet-Komponenten. Dabei kann ein kleiner Kreis von Experten Angriffe auf die eigentlichen Netzknoten ausführen. Typische Hacker-Angriffe kommen von Endsystemen des Internets und richten sich auch gegen Endsysteme wie Firmen-Intranets oder einzelne PCs. Dagegen gibt es eine Reihe von Schutzmöglichkeiten. Es ist jedoch keine einfache Lösung zur Erhöhung der Internet-Sicherheit in Sicht.

  17. Instantaneous BeiDou+GPS RTK positioning with high cut-off elevation angles

    NASA Astrophysics Data System (ADS)

    Teunissen, P. J. G.; Odolinski, R.; Odijk, D.

    2014-04-01

    As the Chinese BeiDou Navigation Satellite System (BDS) has become operational in the Asia-Pacific region, it is of importance to better understand as well as demonstrate the capabilities that a combination of BeiDou with GPS brings to positioning. In this contribution, a formal and empirical analysis is given of the single-epoch RTK positioning capabilities of such a combined system. This will be done for the single- and dual-frequency case, and in comparison with the BDS- and GPS-only performances. It will be shown that with the combined system, when more satellites are available, much larger than the customary cut-off elevations can be used. This is important, as such measurement set-up will significantly increase the GNSS applicability in constrained environments, such as e.g. in urban canyons or when low-elevation multipath is present.

  18. A new empirical solar radiation pressure model for BeiDou GEO satellites

    NASA Astrophysics Data System (ADS)

    Liu, Junhong; Gu, Defeng; Ju, Bing; Shen, Zhen; Lai, Yuwang; Yi, Dongyun

    2016-01-01

    Two classic empirical solar radiation pressure (SRP) models, the Extended Center for Orbit Determination in Europe (CODE) Orbit Model ECOM 5 and ECOM 9 have been widely used for Global Positioning System (GPS) Medium Earth Orbit (MEO) satellites precise orbit determination (POD). However, these two models are not suitable for BeiDou Geostationary Earth Orbit (GEO) satellites due to their special attitude control mode. With the experimental design method this paper proposes a new empirical SRP model for BeiDou GEO satellites, which is featured by three constant terms in DYX directions, two sine terms in DX directions and one cosine term in the Y direction. It is the first time to reveal that the periodic terms in the D direction are more important than those in YX directions for BeiDou GEO satellites. Compared with ECOM 5 and ECOM 9, the BeiDou GEO satellite orbits are significantly stabilized with the new SRP force model. The average orbit overlapping root mean square (RMS) achieved by the proposed model is 7.5 cm in the radial component, which is evidently improved over those of 37.4 and 13.2 cm for ECOM 5 and ECOM 9, respectively. In addition, the correlation coefficients between GEO orbit overlaps precision and the elevation angle of the Sun have been decreased to -0.12, 0.21, and -0.03 in radial, along-track and cross-track components by using the proposed model, while they are -0.94, -0.79 and -0.29 for ECOM 5 and -0.70, 0.21 and 0.10 for ECOM 9. Moreover, the standard deviation (STD) of Satellite Laser Ranging (SLR) data residuals for the GEO satellite C01 is reduced by 37.4% and 16.1% compared with those of ECOM 5 and ECOM 9 SRP models.

  19. A new analytical solar radiation pressure model for current BeiDou satellites: IGGBSPM.

    PubMed

    Tan, Bingfeng; Yuan, Yunbin; Zhang, Baocheng; Hsu, Hou Ze; Ou, Jikun

    2016-01-01

    An analytical solar radiation pressure (SRP) model, IGGBSPM (an abbreviation for Institute of Geodesy and Geophysics BeiDou Solar Pressure Model), has been developed for three BeiDou satellite types, namely, geostationary orbit (GEO), inclined geosynchronous orbit (IGSO) and medium earth orbit (MEO), based on a ray-tracing method. The performance of IGGBSPM was assessed based on numerical integration, SLR residuals and analyses of empirical SRP parameters (except overlap computations). The numerical results show that the integrated orbit resulting from IGGBSPM differs from the precise ephemerides by approximately 5 m and 2 m for GEO and non-GEO satellites, respectively. Moreover, when IGGBSPM is used as an a priori model to enhance the ECOM (5-parameter) model with stochastic pulses, named ECOM + APR, for precise orbit determination, the SLR RMS residual improves by approximately 20-25 percent over the ECOM-only solution during the yaw-steering period and by approximately 40 percent during the yaw-fixed period. For the BeiDou GEO01 satellite, improvements of 18 and 32 percent can be achieved during the out-of-eclipse season and during the eclipse season, respectively. An investigation of the estimated ECOM D0 parameters indicated that the β-angle dependence that is evident in the ECOM-only solution is no longer present in the ECOM + APR solution. PMID:27595795

  20. Experimental study on the precise orbit determination of the BeiDou navigation satellite system.

    PubMed

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-01-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better. PMID:23529116

  1. A new analytical solar radiation pressure model for current BeiDou satellites: IGGBSPM

    PubMed Central

    Tan, Bingfeng; Yuan, Yunbin; Zhang, Baocheng; Hsu, Hou Ze; Ou, Jikun

    2016-01-01

    An analytical solar radiation pressure (SRP) model, IGGBSPM (an abbreviation for Institute of Geodesy and Geophysics BeiDou Solar Pressure Model), has been developed for three BeiDou satellite types, namely, geostationary orbit (GEO), inclined geosynchronous orbit (IGSO) and medium earth orbit (MEO), based on a ray-tracing method. The performance of IGGBSPM was assessed based on numerical integration, SLR residuals and analyses of empirical SRP parameters (except overlap computations). The numerical results show that the integrated orbit resulting from IGGBSPM differs from the precise ephemerides by approximately 5 m and 2 m for GEO and non-GEO satellites, respectively. Moreover, when IGGBSPM is used as an a priori model to enhance the ECOM (5-parameter) model with stochastic pulses, named ECOM + APR, for precise orbit determination, the SLR RMS residual improves by approximately 20–25 percent over the ECOM-only solution during the yaw-steering period and by approximately 40 percent during the yaw-fixed period. For the BeiDou GEO01 satellite, improvements of 18 and 32 percent can be achieved during the out-of-eclipse season and during the eclipse season, respectively. An investigation of the estimated ECOM D0 parameters indicated that the β-angle dependence that is evident in the ECOM-only solution is no longer present in the ECOM + APR solution. PMID:27595795

  2. Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System

    PubMed Central

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-01-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better. PMID:23529116

  3. Effects of spin-orbit coupling on laser cooling of BeI and MgI

    SciTech Connect

    Wan, Mingjie Huang, Duohui; Shao, Juxiang; Li, Yuanyuan; Yu, You; Li, Song

    2015-10-28

    We present the ab initio study of spin-orbit coupling effects on laser cooling of BeI and MgI molecules. Potential energy curves for the X{sup 2}Σ{sup +}{sub 1/2}, A{sup 2}Π{sub 1/2,3/2}, and 2{sup 2}Π{sub 3/2,1/2} states are calculated using multi-reference configuration interaction method plus Davidson corrections. Spectroscopic parameters of BeI and MgI are in excellent agreement with available experimental and theoretical values. The A{sup 2}Π{sub 3/2} state of MgI is a repulsive state. It is an unsuitable scheme for the A{sup 2}Π{sub 3/2}(υ′)← X{sup 2}Σ{sup +}{sub 1/2} (υ″) transition for laser cooling of MgI. Highly diagonally distributed Franck-Condon factors f{sub 00} for the A{sup 2}Π{sub 1/2,3/2} (υ′ = 0) ← X{sup 2}Σ{sup +}{sub 1/2} (υ″ = 0) transitions and suitable radiative lifetimes τ for the A{sup 2}Π{sub 1/2,3/2} (υ′ = 0) of BeI and MgI are obtained. Three laser wavelength drives are required for the A{sup 2}Π{sub 1/2,3/2}(υ′)←X{sup 2}Σ{sup +}{sub 1/2} (υ″) transitions of BeI and MgI. The proposed cooling wavelengths of BeI and MgI are both in the violet region. The results imply the feasibility of laser cooling of BeI and MgI, and that laser cooling of BeI is more possible.

  4. Crystal structure of the branching enzyme I (BEI) from Oryza sativa L with implications for catalysis and substrate binding.

    PubMed

    Noguchi, Junji; Chaen, Kimiko; Vu, Nhuan Thi; Akasaka, Taiki; Shimada, Hiroaki; Nakashima, Takashi; Nishi, Aiko; Satoh, Hikaru; Omori, Toshiro; Kakuta, Yoshimitsu; Kimura, Makoto

    2011-08-01

    Starch-branching enzyme catalyzes the cleavage of α-1, 4-linkages and the subsequent transfer of α-1,4 glucan to form an α-1,6 branch point in amylopectin. Sequence analysis of the rice-branching enzyme I (BEI) indicated a modular structure in which the central α-amylase domain is flanked on each side by the N-terminal carbohydrate-binding module 48 and the α-amylase C-domain. We determined the crystal structure of BEI at a resolution of 1.9 Å by molecular replacement using the Escherichia coli glycogen BE as a search model. Despite three modular structures, BEI is roughly ellipsoidal in shape with two globular domains that form a prominent groove which is proposed to serve as the α-polyglucan-binding site. Amino acid residues Asp344 and Glu399, which are postulated to play an essential role in catalysis as a nucleophile and a general acid/base, respectively, are located at a central cleft in the groove. Moreover, structural comparison revealed that in BEI, extended loop structures cause a narrowing of the substrate-binding site, whereas shortened loop structures make a larger space at the corresponding subsite in the Klebsiella pneumoniae pullulanase. This structural difference might be attributed to distinct catalytic reactions, transglycosylation and hydrolysis, respectively, by BEI and pullulanase. PMID:21493662

  5. Intraoperative Schnellschnittuntersuchungen parapylorischer Lymphknoten bei der pyloruserhaltenden Pankreaskopfresektion: Gibt es eine klinische Relevanz?

    PubMed Central

    Riediger, Hartwig; Schulz, Antje; Adam, Ulrich; Krüger, Colin M.

    2014-01-01

    Zusammenfassung Hintergrund Die pyloruserhaltende Pankreaskopfresektion (PPPD) ist als onkologisches Standardverfahren etabliert. Lokal fortgeschrittene Tumoren können eine erweiterte Resektion erforderlich machen. Ebenso soll früheren Arbeiten zufolge bei Tumornachweis in den parapylorischen Lymphknoten (PLK) eine distale Magenresektion im Sinne einer klassischen Whipple-Operation indiziert sein. Entsprechend diesen Empfehlungen haben wir intraoperative Schnellschnittuntersuchungen der PLK in unseren Routineablauf integriert. Im Rahmen dieser Studie haben wir die klinische Relevanz dieses Vorgehens hinterfragt. Methoden Bei 105 onkologischen Patienten im Zeitraum von 2006-2012 bestand die Indikation zur PPPD. In allen Fällen erfolgte eine intraoperative Schnellschnittuntersuchung der PLK. Die Patienten wurden bezüglich Primärtumor, Anzahl der untersuchten Lymphknoten (LK) (gesamt und parapylorisch) sowie Auswirkungen auf das operative Konzept untersucht. Es handelt sich um eine retrospektive Studie, die auf prospektiv erhobenen Daten unserer Pankreasdatenbank basiert. Ergebnisse Die Primärtumoren waren 72 Pankreaskopfkarzinome und 33 extrapankreatische Karzinome (Gallengangskarzinom, Ampullenkarzinom, Duodenalkarzinom). 73 Patienten waren nodalpositiv. Insgesamt wurden 2391 LK untersucht, von denen 325 parapylorisch lokalisiert waren. Die intraoperative Schnellschnittuntersuchung erbrachte lediglich bei 4 Patienten mit Pankreaskopfkarzinom jeweils einen positiven PLK; daraufhin erfolgte eine distale Magenresektion. In keinem der distalen Magenresektate waren Tumorresiduen nachweisbar. Lokale chirurgisch-technische Probleme im Sinne von Durchblutungsstörungen des Magens ergaben sich durch die regionale Lymphadenektomie nicht. PLK waren nur beim Pankreaskarzinom positiv. In der Subgruppe der nodalpositiven Patienten mit Pankreaskopfkarzinom hatten 8% der Patienten einen positiven PLK. Schlussfolgerung Die regionale parapylorische Lymphadenektomie ist beim

  6. An improved method for eliminating BeiDou satellite induced code bias

    NASA Astrophysics Data System (ADS)

    Li, Xin; Li, Xin; Zhang, Xiaohong; Pan, Lin

    2016-04-01

    The BeiDou satellite induced code biases have serious impact on precise positioning which use code measurements. According to the characteristic of code biases which have been confirmed orbit type-, frequency-, and elevation-dependent, an improved method is proposed in this contribution by processing the data from 12 months in 2015 to reduce their adverse effects. Different from the model put forward by Wanninger and Beer (2015),more data sets were used to produce the correction values as weighted least squares and robust estimation were used to build up more accurate model for all IGSO satellites and MEO satellites. The additional method for GEO satellites is applying sidereal filtering to help minimize the code biases. The result of improved method shows that the systematic variations have been eliminated more clearly and the positioning accuracy of PPP solution were better than using traditional model proposed by Wanninger and Beer as well as convergence speed. In addition, the systematic variations in MW combination which serve for ambiguity fixing were removed as well. Morever, after application of the code bias correction method, the convergence time of MW combinations and the fixing rate of DD wide-lane ambiguity resolution have been improved. Key words: BeiDou; code bias; weighted least squares ; robust estimation; Precise Positioning; MW combination; ambiguity resolution

  7. Untersuchung der Störwirkung von LTE auf SRD Anwendungen bei 868 MHz

    NASA Astrophysics Data System (ADS)

    Welpot, M.; Wunderlich, S.; Gaspard, I.

    2014-11-01

    Moderne Hausautomatisierungssysteme, Alarmanlagen oder auch Funk-Zugangssysteme in Haus und Automobil setzen auf frei nutzbare Frequenzen in ISM/SRD-Bändern. Die rasante Zunahme an privaten und kommerziell genutzten Applikationen im SRD-Band bei 868 MHz und der Ausbau der LTE-Mobilfunknetze im Frequenzbereich unterhalb von 1 GHz ("Digital Dividend") wirft zunehmend die Frage nach der Funkverträglichkeit dieser Systeme untereinander auf. Während die SRD-Funkmodule auf eine geringe Sendeleistung von ~ +14 dBm beschränkt sind (Ralf and Thomas, 2009), beträgt die maximale LTE-Sendeleistung im Uplink nach (ETSI-Norm, 2011) +23 dBm. Zusammen mit der Einführung von LTE im Frequenzbereich unterhalb 1 GHz als DSL-Ersatz vor allem in ländlichen Gebieten, ergibt sich damit als mögliches Störszenario, dass durch die Aussendung des LTE-Endgerätes im Bereich von ca. 850 MHz die SRD-Funkverbindungen bei 868 MHz insbesondere dann gestört werden, wenn die Antennen beider Funksysteme räumlich nahe zueinander angeordnet sind und folglich nur eine geringe zusätzliche Entkopplung der Systeme bieten. In der vorliegenden Arbeit wird das LTE-Störpotential auf SRD-Empfänger praxisnah untersucht.

  8. USER'S GUIDE TO THE PERSONAL COMPUTER VERSION OF THE BIOGENIC EMISSIONS INVENTORY SYSTEM (PC-BEIS2)

    EPA Science Inventory

    The document is a user's guide for an updated Personal Computer version of the Biogenic Emissions Inventory System (PC-BEIS2), allowing users to estimate hourly emissions of biogenic volatile organic compounds (BVOCs) and soil nitrogen oxide emissions for any county in the contig...

  9. Analysis on coverage ability of BeiDou navigation satellite system for manned spacecraft

    NASA Astrophysics Data System (ADS)

    Zhao, Sihao; Yao, Zheng; Zhuang, Xuebin; Lu, Mingquan

    2014-12-01

    To investigate the service ability of the BeiDou Navigation Satellite System (BDS) for manned spacecraft, both the current regional and the future-planned global constellations of BDS are introduced and simulated. The orbital parameters of the International Space Station and China's Tiangong-1 spacelab are used to create the simulation scenario and evaluate the performance of the BDS constellations. The number of visible satellites and the position dilution (PDOP) of precision at the spacecraft-based receiver are evaluated. Simulation and analysis show quantitative results on the coverage ability and time percentages of both the current BDS regional and future global constellations for manned-space orbits which can be a guideline to the applications and mission design of BDS receivers on manned spacecraft.

  10. Pilot Evaluation of Integrating GLONASS, Galileo and BeiDou with GPS in Araim

    NASA Astrophysics Data System (ADS)

    El-Mowafy, Ahmed

    2016-03-01

    In this pilot study, availability of the Advanced Receiver Autonomous Integrity Monitoring (ARAIM) when integrating various combinations of satellite constellations including; Galileo, GLONASS and BeiDou with GPS is investigated. The Multiple Hypothesis Solution Separation method was applied using one month of real data. The data was collected at stations of known positions, located in regions that have different coverage levels by the tested constellations. While most previous studies used simulated data, the importance of using real data is twofold. It allows for the use of actual User Range Accuracy (URA) received within the satellite navigation message, which is a fundamental component for computation of the integrity protection level; and the computation of vertical position errors to validate the integrity approach. Results show that the vertical position error was always bounded by the protection level during the test period and the ARAIM availability can reach 100% of the time when using all constellations even though some constellations are yet incomplete.

  11. Minimalinvasive endovaskuläre Stent-Therapie bei Erkrankungen in der thorakalen Aorta

    NASA Astrophysics Data System (ADS)

    Voss, Bernhard; Bauernschmitt, Robert; Brockmann, Gernot; Lange, Rüdiger

    Die Inzidenz der Aortenerkrankungen nimmt aufgrund der Überalterung der Bevölkerung stetig zu und hat sich innerhalb der letzten 20 Jahre von 2,9 auf 10,9 pro 100.000 Einwohner mehr als verdreifacht [1]. Bei Aortenerkrankungen muss zwischen Aneurysmen und Dissektionen unterschieden werden. Der Begriff Aneurysma (Abb. 62.1) bezeichnet die Ausweitung eines arteriellen Blutgefäßes. Sind dabei alle Wandschichten, also innere Schicht (Intima), mittlere Schicht (Media) und äußere Schicht (Adventitia) betroffen, so spricht man von einem echten Aneurysma (Aneurysma verum). Besteht die Aneurysmawand nur aus adventitiellem Gewebe, spricht man von einem falschen Aneurysma. Ursache für ein Aneurysma ist eine Schwächung der elastischen Kräfte der Media, die dann dem intravaskulären Druck nicht mehr standhalten kann.

  12. Real-time retrieval of precipitable water vapor from GPS and BeiDou observations

    NASA Astrophysics Data System (ADS)

    Lu, Cuixian; Li, Xingxing; Nilsson, Tobias; Ning, Tong; Heinkelmann, Robert; Ge, Maorong; Glaser, Susanne; Schuh, Harald

    2015-09-01

    The rapid development of the Chinese BeiDou Navigation Satellite System (BDS) brings a promising prospect for the real-time retrieval of zenith tropospheric delays (ZTD) and precipitable water vapor (PWV), which is of great benefit for supporting the time-critical meteorological applications such as nowcasting or severe weather event monitoring. In this study, we develop a real-time ZTD/PWV processing method based on Global Positioning System (GPS) and BDS observations. The performance of ZTD and PWV derived from BDS observations using real-time precise point positioning (PPP) technique is carefully investigated. The contribution of combining BDS and GPS for ZTD/PWV retrieving is evaluated as well. GPS and BDS observations of a half-year period for 40 globally distributed stations from the International GNSS Service Multi-GNSS Experiment and BeiDou Experiment Tracking Network are processed. The results show that the real-time BDS-only ZTD series agree well with the GPS-only ZTD series in general: the RMS values are about 11-16 mm (about 2-3 mm in PWV). Furthermore, the real-time ZTD derived from GPS-only, BDS-only, and GPS/BDS combined solutions are compared with those derived from the Very Long Baseline Interferometry. The comparisons show that the BDS can contribute to real-time meteorological applications, slightly less accurately than GPS. More accurate and reliable water vapor estimates, about 1.3-1.8 mm in PWV, can be obtained if the BDS observations are combined with the GPS observations in the real-time PPP data processing. The PWV comparisons with radiosondes further confirm the performance of BDS-derived real-time PWV and the benefit of adding BDS to standard GPS processing.

  13. Reduktion der Invasivität bei nadelbasierter Bewegungskompensation für navigierte Eingriffe im Abdomen

    NASA Astrophysics Data System (ADS)

    Maier-Hein, L.; Tekbas, A.; Franz, A. M.; Tetzlaff, R.; Müller, S. A.; Pianka, F.; Wolf, I.; Kauczor, H.-U.; Schmied, B. M.; Meinzer, H.-P.

    Diese Arbeit stellt eine in-vivo Genauigkeitsstudie über das Kombinieren interner und externer Marker für die Bewegungskompensation bei Leberinterventionen vor. Abhängig von der Anzahl und Anordnung der verwendeten Marker sowie der angewandten Echtzeittransformation wurde bei kontinuierlicher Atmung eine Schätzgenauigkeit der Zielposition zwischen 1 und 5 mm erreicht. Das Hinzufügen einer einzigen Hilfsnadel zu einer Menge von Hautmarkern führte zu einer Fehlerreduktion von über 50%. Die Ergebnisse dieser Studie können in der Praxis verwendet werden, um basierend auf dem Tradeoff zwischen geringer Invasivität und hoher Genauigkeit eine geeignete Kombination von internen und externen Markern für eine gegebene Fragestellung zu wählen.

  14. The application of the nucleolar organizer region silver staining (AgNOR) to backscattered electron imaging (BEI).

    PubMed

    Thiebaut, F; Rigaut, J P; Feren, K; Reith, A

    1984-01-01

    Until recently scanning electron microscopes were mainly used to observe surfaces. However, it has been proved that a backscattered electron detector can give an image (BEI) of the specimen's internal structure after heavy metal staining. In this paper, we report how we have applied the silver staining for NOR-associated proteins to scanning electron microscopy, studying C3H10T1/2 cells in culture. This technique allows to localize, inside the nucleus, the nucleolar arrangement of AgNOR-associated proteins. In BEI imaging, the silver staining shows several intranucleolar silver spot-like deposits sometimes associated in "doublets" as on metaphasic chromosomes. These silver grains probably represent the fibrillar centre location, thought to be the interphasic counterpart of the NORs. However, these silver spot granules are more numerous during interphase. PMID:6085018

  15. Evaluation of improved land use and canopy representation in BEIS v3.61 with biogenic VOC measurements in California

    NASA Astrophysics Data System (ADS)

    Bash, J. O.; Baker, K. R.; Beaver, M. R.

    2015-09-01

    Biogenic volatile organic compounds (BVOC) participate in reactions that can lead to secondarily formed ozone and particulate matter (PM) impacting air quality and climate. BVOC emissions are important inputs to chemical transport models applied on local to global scales but considerable uncertainty remains in the representation of canopy parameterizations and emission algorithms from different vegetation species. The Biogenic Emission Inventory System (BEIS) has been used to support both scientific and regulatory model assessments for ozone and PM. Here we describe a new version of BEIS which includes updated input vegetation data and canopy model formulation for estimating leaf temperature and vegetation data on estimated BVOC. The Biogenic Emission Landuse Database (BELD) was revised to incorporate land use data from the Moderate Resolution Imaging Spectroradiometer (MODIS) land product and 2006 National Land Cover Database (NLCD) land coverage. Vegetation species data is based on the US Forest Service (USFS) Forest Inventory and Analysis (FIA) version 5.1 for years from 2002 to 2013 and US Department of Agriculture (USDA) 2007 census of agriculture data. This update results in generally higher BVOC emissions throughout California compared with the previous version of BEIS. Baseline and updated BVOC emissions estimates are used in Community Multiscale Air Quality Model (CMAQ) simulations with 4 km grid resolution and evaluated with measurements of isoprene and monoterpenes taken during multiple field campaigns in northern California. The updated canopy model coupled with improved land use and vegetation representation resulted in better agreement between CMAQ isoprene and monoterpene estimates compared with these observations.

  16. Evaluation of improved land use and canopy representation in BEIS v3.61 with biogenic VOC measurements in California

    NASA Astrophysics Data System (ADS)

    Bash, Jesse O.; Baker, Kirk R.; Beaver, Melinda R.

    2016-06-01

    Biogenic volatile organic compounds (BVOC) participate in reactions that can lead to secondarily formed ozone and particulate matter (PM) impacting air quality and climate. BVOC emissions are important inputs to chemical transport models applied on local to global scales but considerable uncertainty remains in the representation of canopy parameterizations and emission algorithms from different vegetation species. The Biogenic Emission Inventory System (BEIS) has been used to support both scientific and regulatory model assessments for ozone and PM. Here we describe a new version of BEIS which includes updated input vegetation data and canopy model formulation for estimating leaf temperature and vegetation data on estimated BVOC. The Biogenic Emission Landuse Database (BELD) was revised to incorporate land use data from the Moderate Resolution Imaging Spectroradiometer (MODIS) land product and 2006 National Land Cover Database (NLCD) land coverage. Vegetation species data are based on the US Forest Service (USFS) Forest Inventory and Analysis (FIA) version 5.1 for 2002-2013 and US Department of Agriculture (USDA) 2007 census of agriculture data. This update results in generally higher BVOC emissions throughout California compared with the previous version of BEIS. Baseline and updated BVOC emission estimates are used in Community Multiscale Air Quality (CMAQ) Model simulations with 4 km grid resolution and evaluated with measurements of isoprene and monoterpenes taken during multiple field campaigns in northern California. The updated canopy model coupled with improved land use and vegetation representation resulted in better agreement between CMAQ isoprene and monoterpene estimates compared with these observations.

  17. Accuracy and reliability of multi-GNSS real-time precise positioning: GPS, GLONASS, BeiDou, and Galileo

    NASA Astrophysics Data System (ADS)

    Li, Xingxing; Ge, Maorong; Dai, Xiaolei; Ren, Xiaodong; Fritsche, Mathias; Wickert, Jens; Schuh, Harald

    2015-06-01

    In this contribution, we present a GPS+GLONASS+BeiDou+Galileo four-system model to fully exploit the observations of all these four navigation satellite systems for real-time precise orbit determination, clock estimation and positioning. A rigorous multi-GNSS analysis is performed to achieve the best possible consistency by processing the observations from different GNSS together in one common parameter estimation procedure. Meanwhile, an efficient multi-GNSS real-time precise positioning service system is designed and demonstrated by using the multi-GNSS Experiment, BeiDou Experimental Tracking Network, and International GNSS Service networks including stations all over the world. The statistical analysis of the 6-h predicted orbits show that the radial and cross root mean square (RMS) values are smaller than 10 cm for BeiDou and Galileo, and smaller than 5 cm for both GLONASS and GPS satellites, respectively. The RMS values of the clock differences between real-time and batch-processed solutions for GPS satellites are about 0.10 ns, while the RMS values for BeiDou, Galileo and GLONASS are 0.13, 0.13 and 0.14 ns, respectively. The addition of the BeiDou, Galileo and GLONASS systems to the standard GPS-only processing, reduces the convergence time almost by 70 %, while the positioning accuracy is improved by about 25 %. Some outliers in the GPS-only solutions vanish when multi-GNSS observations are processed simultaneous. The availability and reliability of GPS precise positioning decrease dramatically as the elevation cutoff increases. However, the accuracy of multi-GNSS precise point positioning (PPP) is hardly decreased and few centimeter are still achievable in the horizontal components even with 40 elevation cutoff. At 30 and 40 elevation cutoffs, the availability rates of GPS-only solution drop significantly to only around 70 and 40 %, respectively. However, multi-GNSS PPP can provide precise position estimates continuously (availability rate is more than 99

  18. Assessment of BeiDou differential code bias variations from multi-GNSS network observations

    NASA Astrophysics Data System (ADS)

    Jin, S. G.; Jin, R.; Li, D.

    2016-02-01

    The differential code bias (DCB) of global navigation satellite systems (GNSSs) affects precise ionospheric modeling and applications. In this paper, daily DCBs of the BeiDou Navigation Satellite System (BDS) are estimated and investigated from 2-year multi-GNSS network observations (2013-2014) based on global ionospheric maps (GIMs) from the Center for Orbit Determination in Europe (CODE), which are compared with Global Positioning System (GPS) results. The DCB of BDS satellites is a little less stable than GPS solutions, especially for geostationary Earth orbit (GEO) satellites. The BDS GEO observations decrease the precision of inclined geosynchronous satellite orbit (IGSO) and medium Earth orbit (MEO) DCB estimations. The RMS of BDS satellites DCB decreases to about 0.2 ns when we remove BDS GEO observations. Zero-mean condition effects are not the dominant factor for the higher RMS of BDS satellites DCB. Although there are no obvious secular variations in the DCB time series, sub-nanosecond variations are visible for both BDS and GPS satellites DCBs during 2013-2014. For satellites in the same orbital plane, their DCB variations have similar characteristics. In addition, variations in receivers DCB in the same region are found with a similar pattern between BDS and GPS. These variations in both GPS and BDS DCBs are mainly related to the estimated error from ionospheric variability, while the BDS DCB intrinsic variation is in sub-nanoseconds.

  19. Impact of tracking station distribution structure on BeiDou satellite orbit determination

    NASA Astrophysics Data System (ADS)

    Zhang, Rui; Zhang, Qin; Huang, Guanwen; Wang, Le; Qu, Wei

    2015-11-01

    The racking station distribution structure plays an important role in GNSS satellite orbit determination. Due to the current satellite distribution of the BeiDou satellite navigation system (BDS), the problem how to construct a reasonable distribution of tracking stations to obtain BDS satellite orbits with high precision has become a highly imperative issue. Based on the theory of dynamic orbit determination, two different station distributions were analyzed to study their impact on BDS precise and real-time orbit determination. Subsequently, the impact of Satellite Position Dilution of Precision (SPDOP) values on orbit determination was analyzed. Finally, an improved scheme for the tracking station distribution was designed based on the original scheme. The numerical results show that the SPDOP value can be used to evaluate the contribution of the tracking stations distribution on the BDS IGSO and MEO satellites orbit determination. In addition, the tracking stations which focus on the Asia-Pacific region play a key role in current BDS orbit determination.

  20. Tropospheric wet refractivity tomography based on the BeiDou satellite system

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoying; Wang, Xianliang; Dai, Ziqiang; Ke, Fuyang; Cao, Yunchang; Wang, Feifei; Song, Lianchun

    2014-03-01

    This paper presents a novel approach for assessing the precision of the wet refractivity field using BDS (BeiDou navigation satellite system) simulations only, GPS, and BDS+GPS for the Shenzhen and Hongkong GNSS network. The simulations are carried out by adding artificial noise to a real observation dataset. Instead of using the d and s parameters computed from slant wet delay, as in previous studies, we employ the Bias and RMS parameters, computed from the tomography results of total voxels, in order to obtain a more direct and comprehensive evaluation of the precision of the refractivity field determination. The results show that: (1) the precision of tropospheric wet refractivity estimated using BDS alone (only 9 satellites used) is basically comparable to that of GPS; (2) BDS+GPS (as of current operation) may not be able to significantly improve the data's spatial density for the application of refractivity tomography; and (3) any slight increase in the precision of refractivity tomography, particularly in the lower atmosphere, bears great significance for any applications dependent on the Chinese operational meteorological service.

  1. Using BeiDou system for precise positioning in central Europe

    NASA Astrophysics Data System (ADS)

    Kwasniak, Dawid; Cellmer, Slawomir; Nowel, Krzysztof

    2016-04-01

    In 2012 the Chinese navigation satellite system called BeiDou System (BDS) has reached the regional operational capabilities over the area of East Asia. Currently the BDS system consists of 5 medium orbit satellites MEO, 6 geosynchronous satellites IGSO and 5 geostationary satellites GEO and provides regional coverage by its navigation signals. Also in Europe BDS satellites can be used to determine position. In 2015 the third phase of BSD system development has started, aimed at providing global coverage and compatibility with other GNSS systems. As a result, BDS will broadcast signals at the same frequency as GPS L1 and L5 and Galileo E1, E5a and E5b. In the presented research we carried out relative positioning using the MAFA method. This was the first time when this method was applied to process BDS signals. The results show that it is possible to obtain precise position in central Europe using BDS signals only. However, with its current constellation, this is not possible 24/7, but in periodic time windows.

  2. Estimating zenith tropospheric delays from BeiDou navigation satellite system observations.

    PubMed

    Xu, Aigong; Xu, Zongqiu; Ge, Maorong; Xu, Xinchao; Zhu, Huizhong; Sui, Xin

    2013-01-01

    The GNSS derived Zenith Tropospheric Delay (ZTD) plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS) was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS). The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages. PMID:23552104

  3. [Vegetarische und vegane Ernährung bei Kindern - Stand der Forschung und Forschungsbedarf].

    PubMed

    Keller, Markus; Müller, Stine

    2016-01-01

    Die Praxis vegetarischer Ernährungsformen ist in Deutschland im letzten Jahrzehnt deutlich angestiegen. Allerdings ist der Anteil vegetarischer und veganer Kinder dabei unbekannt. Studien mit Erwachsenen zeigen das präventive Potenzial, aber auch potenzielle Schwachstellen pflanzenbasierter Kostformen. Die Vorteile und Risiken einer vegetarischen bzw. veganen Ernährung im Kindesalter wurden bisher jedoch relativ selten untersucht. Außerdem lassen das unterschiedliche Alter der Kinder, das heterogene Studiendesign sowie die teilweise geringe Probandenzahl der Studien keine verbindlichen Aussagen zu. In dieser Übersichtsarbeit werden die Ergebnisse der wenigen Studien zu vegetarisch und vegan ernährten Kindern (< 12 Jahren) in Nordamerika und Europa zusammengefasst. Demnach lag die Zufuhr von Nahrungsenergie und Makronährstoffen vegetarischer und veganer Kinder meist näher an den Empfehlungen der Fachgesellschaften als die Ernährung gleichaltriger Mischkostkinder. Ebenso wiesen vegetarisch und vegan ernährte Kinder eine höhere Zufuhr von und bessere Versorgung mit verschiedenen Vitaminen und Mineralstoffen auf. Häufiger zeigten sich jedoch Defizite bei Vitamin B12, Zink, Kalzium, Eisen und Vitamin D. Das Wachstum und die Entwicklung vegetarisch und vegan ernährter Kinder entsprachen weitgehend den Referenzstandards, wobei sie dazu tendierten, leichter, schlanker und (< 5 Jahren) auch kleiner zu sein. Aufgrund der unzureichenden Studienlage besteht erheblicher Forschungsbedarf zu den Auswirkungen einer vegetarischen und veganen Ernährung im Kindesalter. PMID:27160086

  4. Estimating Zenith Tropospheric Delays from BeiDou Navigation Satellite System Observations

    PubMed Central

    Xu, Aigong; Xu, Zongqiu; Ge, Maorong; Xu, Xinchao; Zhu, Huizhong; Sui, Xin

    2013-01-01

    The GNSS derived Zenith Tropospheric Delay (ZTD) plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS) was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS). The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages. PMID:23552104

  5. [COPD und Klangtherapie: Pilotstudie zur Wirksamkeit einer Behandlung mit Körpertambura bei COPD-Patienten].

    PubMed

    Hartwig, Bernhard; Schmidt, Stefan; Hartwig, Isabella

    2016-01-01

    Hintergrund: Erkrankungen der Atemorgane treten mit steigendem Alter öfter auf, nehmen weltweit zu und sind häufige Ursachen für Morbidität und Mortalität. In dieser Pilotstudie wurde der Frage nachgegangen, ob eine einmalige 10-minütige Behandlung mit einer Körpertambura eine signifikante und effektive Verbesserung der Lungenfunktion von Patienten mit chronisch-obstruktiver Lungenerkrankung (COPD; GOLD-Stadium A oder B) erbringen kann. Patienten und Methoden: 54 Probanden konnten je zur Hälfte in eine Behandlungsgruppe (Körpertambura) und eine aktive Kontrollgruppe (Atemtherapie) randomisiert werden. Eine Bestimmung der Lungenfunktionsmessparameter «Einsekundenkapazität» (FEV1) und «inspiratorische Vitalkapazität» (IVC) zu den Zeitpunkten T1 (Baseline), T2 (direkt nach Behandlung) und als Follow-up etwa 3 Wochen nach T1 (T3). Ergebnisse: Die Behandlungsgruppe zeigte sich der Kontrollgruppe in beiden Werten signifikant überlegen. Die Zeit-×-Gruppe-Interaktion (Varianzanalyse) ergab p = 0,001 (FEV1) bzw. p = 0,04 (IVC). Die Behandlungsgruppe zeigte bei beiden Werten eine Verbesserung von klinischer Relevanz. Schlussfolgerung: Diese Ergebnisse zeigen, dass die Klangbehandlung mittels einer Körpertambura - neben den schulmedizinischen, leitliniengerechten Therapien - eine zusätzliche, nebenwirkungsarme, aber durchaus klinisch wirksame Option für die Behandlung von COPD-Patienten darstellen kann, um deren Lebensqualität zu stabilisieren und zu verbessern. PMID:27606616

  6. The influence of different types of satellite exiting in system RAIM performance in BeiDou Satellite Navigation System

    NASA Astrophysics Data System (ADS)

    Wang, Shi-tai; Peng, Jun-huan

    2015-12-01

    The space constellation of BeiDou Navigation Satellite System(BDS)has three main components, Geostationary Earth Orbits (GEOs), Medium Earth Orbits (MEOs) and Inclined Geosynchronous Satellite Orbits(IGSOs).This paper selected 6 satellite respectively in three types to simulate their exiting service, and used the statistical methods to assess receiver autonomous integrity monitoring RAIM availability and fault detection FD capability of BeiDou14 Phase with 14 satellites under the circumstances. This paper assessed RAIM availability performance from satellites and constellation geometry configuration by the number of visible satellites (NVS, NVS>~5) and position dilution of precision (PDOP, PDOP<=6) together. The FD capability of RAIM is assessed by the maximum minimal detectable bias (MDB) and the maximum minimal detectable effect (MDE). The analyses of simulation results testify that the exiting of single MEO or IGSO satellite have no obvious effect on RAIM availability and error detection ability. However GEO satellite's exiting can make the number of points in where the constellation geometry is not available and maximum minimum detectable deviation and maximum minimum detectable influence significantly increase. Relative to other two satellites, GEO satellites' health have a significant impact on the RAIM performance of BDS.

  7. Ambiguity resolved precise point positioning with GPS and BeiDou

    NASA Astrophysics Data System (ADS)

    Pan, Li; Xiaohong, Zhang; Fei, Guo

    2016-07-01

    This paper focuses on the contribution of the global positioning system (GPS) and BeiDou navigation satellite system (BDS) observations to precise point positioning (PPP) ambiguity resolution (AR). A GPS + BDS fractional cycle bias (FCB) estimation method and a PPP AR model were developed using integrated GPS and BDS observations. For FCB estimation, the GPS + BDS combined PPP float solutions of the globally distributed IGS MGEX were first performed. When integrating GPS observations, the BDS ambiguities can be precisely estimated with less than four tracked BDS satellites. The FCBs of both GPS and BDS satellites can then be estimated from these precise ambiguities. For the GPS + BDS combined AR, one GPS and one BDS IGSO or MEO satellite were first chosen as the reference satellite for GPS and BDS, respectively, to form inner-system single-differenced ambiguities. The single-differenced GPS and BDS ambiguities were then fused by partial ambiguity resolution to increase the possibility of fixing a subset of decorrelated ambiguities with high confidence. To verify the correctness of the FCB estimation and the effectiveness of the GPS + BDS PPP AR, data recorded from about 75 IGS MGEX stations during the period of DOY 123-151 (May 3 to May 31) in 2015 were used for validation. Data were processed with three strategies: BDS-only AR, GPS-only AR and GPS + BDS AR. Numerous experimental results show that the time to first fix (TTFF) is longer than 6 h for the BDS AR in general and that the fixing rate is usually less than 35 % for both static and kinematic PPP. An average TTFF of 21.7 min and 33.6 min together with a fixing rate of 98.6 and 97.0 % in static and kinematic PPP, respectively, can be achieved for GPS-only ambiguity fixing. For the combined GPS + BDS AR, the average TTFF can be shortened to 16.9 min and 24.6 min and the fixing rate can be increased to 99.5 and 99.0 % in static and kinematic PPP, respectively. Results also show that GPS + BDS PPP AR outperforms

  8. Carrier-Doppler-based real-time two way satellite frequency transfer and its application in BeiDou system

    NASA Astrophysics Data System (ADS)

    Liu, Zengjun; Gong, Hang; Yang, Wenke; Zhu, Xiangwei; Ou, Gang

    2014-09-01

    Two-way satellite time and frequency transfer (TWSTFT) method is valuable for precise time and frequency transfer. The frequency could be directly transferred by utilizing two-way carrier Doppler measurement. This method requires each station observing both its own and associated station’s transponder signals transferred by satellite. In BeiDou system (BDS), the reference station and the field station construct a two-way link via a GEO satellite, and the field station sends pseudorange and carrier phase information to the reference station by transmission signal, in order to achieve real time TWSTFT. This paper analyzes the theory of carrier Doppler based TWSTFT (called CD-TWSTFT), and validates it by using on line data of BDS. The results demonstrated that the performance of CD TWSTFT is much better than code based TWSTFT in short-term frequency transfer and almost same at long-term frequency transfer.

  9. Precise positioning with current multi-constellation Global Navigation Satellite Systems: GPS, GLONASS, Galileo and BeiDou.

    PubMed

    Li, Xingxing; Zhang, Xiaohong; Ren, Xiaodong; Fritsche, Mathias; Wickert, Jens; Schuh, Harald

    2015-01-01

    The world of satellite navigation is undergoing dramatic changes with the rapid development of multi-constellation Global Navigation Satellite Systems (GNSSs). At the moment more than 70 satellites are already in view, and about 120 satellites will be available once all four systems (BeiDou + Galileo + GLONASS + GPS) are fully deployed in the next few years. This will bring great opportunities and challenges for both scientific and engineering applications. In this paper we develop a four-system positioning model to make full use of all available observations from different GNSSs. The significant improvement of satellite visibility, spatial geometry, dilution of precision, convergence, accuracy, continuity and reliability that a combining utilization of multi-GNSS brings to precise positioning are carefully analyzed and evaluated, especially in constrained environments. PMID:25659949

  10. Precise positioning with current multi-constellation Global Navigation Satellite Systems: GPS, GLONASS, Galileo and BeiDou

    PubMed Central

    Li, Xingxing; Zhang, Xiaohong; Ren, Xiaodong; Fritsche, Mathias; Wickert, Jens; Schuh, Harald

    2015-01-01

    The world of satellite navigation is undergoing dramatic changes with the rapid development of multi-constellation Global Navigation Satellite Systems (GNSSs). At the moment more than 70 satellites are already in view, and about 120 satellites will be available once all four systems (BeiDou + Galileo + GLONASS + GPS) are fully deployed in the next few years. This will bring great opportunities and challenges for both scientific and engineering applications. In this paper we develop a four-system positioning model to make full use of all available observations from different GNSSs. The significant improvement of satellite visibility, spatial geometry, dilution of precision, convergence, accuracy, continuity and reliability that a combining utilization of multi-GNSS brings to precise positioning are carefully analyzed and evaluated, especially in constrained environments. PMID:25659949

  11. Herausforderungen und Best Practices bei der Speicherung von multi-valued Attributen in LDAP-basierten Verzeichnisdiensten

    NASA Astrophysics Data System (ADS)

    Hommel, Wolfgang; Pluta, Daniel

    LDAP-basierte Verzeichnisdienste unterscheiden sich von relationalen Datenbankmanagementsystemen unter anderem stark bezüglich der Datenmodellierung. Dieser Artikel vertieft eingangs die Herausforderungen bei der LDAP-spezifischen Abbildung von Relationen zwischen mehreren multivalued Attributen. Die Diskussion erfolgt vor dem Hintergrund, dass einerseits Verzeichnisdienste generell nur bedingt zur Speicherung von Relationen geeignet sind und dass andererseits multi-valued Attribute ein mächtiges LDAP-Instrument sind, zu dem es in relationalen Datenbanksystemen keine direkte Entsprechung gibt. Anschließend werden Lösungskonzepte vorgestellt und mögliche Weiterentwicklungen des IntegraTUM-LDAP-Schemas zu deren Umsetzung skizziert, eine exemplarische Implementierung präsentiert und die Ergebnisse der bisherigen Entwicklung des IntegraTUM-Schemas gegenübergestellt.

  12. Heavy Metals in Sediment from Bei Shan River: Distribution, Relationship with Soil Characteristics and Multivariate Assessment of Contamination Sources.

    PubMed

    Xun, Yan; Xuegang, Luo

    2015-07-01

    The concentrations and correlation between some heavy metals (Mn, Cd, Cr, Cu, Ni, Zn and Pb) measured in sediments in part of Bei shan River near uranium mill tailings were studied. The mean concentration of Cr (57.7 mg/g) was more than the mean values established for uncultivated areas worldwide (46.3 mg/g). Negative correlations with pH and positive correlations with organic matter have been observed for most of elements analyzed in this study. Correlation analysis showed that all metals except Cr are highly correlated (p ≤ 0.01, p ≤ 0.05). This may indicate the different origin or controlling factors of Cr in analyzed sediments. Cluster analysis highlighted the lithogenic origin of heavy metals (Mn, Cd, Cu, Ni, Zn and Pb) and pointed out the primary input of Cr from anthropogenic sources. PMID:26006719

  13. The contribution of Cu2+, Fe 2+, Fe 3+ to bluish green color of HuBei turquoise

    NASA Astrophysics Data System (ADS)

    Guo, Ying; Jin, Lili; Sun, Hongjuan

    2010-11-01

    Cu2+, Fe2+ and Fe3+ of 146 pieces of turquoises from ZhuShan, HuBei province are researched of their contribution to the color of bluish green. Without consideration of its mineral water on the effects of color chroma, the content of these three cations are confirmed by chemical composition analysis, and then their specific contribution to lightness, chroma and hue are quantified within the uniform color space CIE L*a*b*. Consequently, it is considered that Cu2+ determines turquoise's vivid blue, and Fe2+ makes color changed to green and improves the chroma slightly, as a result it enhances the visual appearance a little too; while Fe3+ leads to red and yellow tone and makes chroma descended simultaneously, with its increment, the color appears low saturated brown, and then the color quality reduced.

  14. Comparison of Optical and SEM-BEI Inclusion Analyses of VIM-VAR Nickel-Titanium Alloy

    NASA Astrophysics Data System (ADS)

    Sczerzenie, Frank; Paul, Graeme W.; Belden, Clarence; Fasching, Audrey

    2011-07-01

    The ASTM Standard for NiTi alloys does not specify the method to be used for the analysis of inclusions. Quantitative analysis is generally done by optical metallography with a computer program to measure size and area fraction. This study gives a comparison of quantitative analyses of inclusions by scanning electron microscopy using backscattered electron imaging (SEM-BEI) and quantitative analyses by optical metallography. Seven samples of 6.3-mm hot-rolled NiTi were evaluated. The coil samples were selected to exhibit a wide range of inclusion content. Each sample had a different Ni to Ti ratio corresponding to a different transformation temperature range (TTR) from A s = -25 °C (Ni = 50.79 a/o) to A s = +95 °C (Ni = 49.63 a/o). Quantitative analyses by optical and by SEM-BEI are in reasonable good agreement for maximum particle size and maximum area fraction. Both methods of analysis show that carbide and intermetallic oxide inclusion populations in VIM-VAR hot-rolled coil vary significantly in the amount and size of inclusions with the alloy transformation temperature. Therefore, an analysis of a larger number of samples at each TTR is needed to develop statistically precise data. All carbide inclusions were less than 12.5 μm and less than 1.0% area fraction in all the samples. Maximum size and area fraction of carbides decreased as TTR increased. Intermetallic oxide size and area fraction increased with increasing TTR Intermetallic oxides are fractured and separated from the matrix during hot working. However, stringering is very limited. The fracturing appears to happen in high TTR alloys but not in low TTR alloys. This dependence on TTR suggests that chemistry in or around the oxides affects their fracture behavior.

  15. Multi-GNSS meteorology: Real-time retrieving of atmospheric parameters from GPS, GLONASS, BeiDou and Galileo observations

    NASA Astrophysics Data System (ADS)

    Li, Xingxing; Dick, Galina; Lu, Cuixian; Ge, Maorong; Nilsson, Tobias; Fritsche, Mathias; Wickert, Jens; Schuh, Harald

    2015-04-01

    The rapid development of multi-constellation GNSSs (Global Navigation Satellite Systems, e.g., BeiDou, Galileo, GLONASS, GPS) and the IGS (International GNSS Service) Multi-GNSS Experiment (MGEX) bring great opportunities and challenges for real-time determination of tropospheric zenith total delays (ZTD) and integrated water vapor (IWV) to improve numerical weather prediction (NWP), especially for nowcasting or severe weather event monitoring. The fusion of multiple GNSSs will significantly increase the number of satellites, optimizing the observation geometry. One result is the availability of more tropospheric slant delays, and consequently a more accurate and robust ZTD/IWV monitoring can be expected. This is especially beneficial in areas where satellite signals are blocked, such as urban areas, or in the equatorial latitudes, where the GNSS signals may be disturbed or even lost due to ionospheric scintillations. In this contribution, we develop a multi-system (BeiDou+Galileo+GLONASS+GPS) processing model to fully exploit all the observations from these systems for the derivation of the real-time ZTD/IWV. A prototype multi-GNSS real-time ZTD/IWV monitoring system is also designed and realized at GFZ and runs in PPP mode for all of the globally distributed MGEX stations. The processing results of the first half year of 2014 are carefully analyzed to assess the quality of the ZTD series derived from different constellations and also evaluate the contribution of multi-GNSS fusion to ZTD/IWV estimates. Furthermore, the Very Long Baseline Interferometry (VLBI) technique is used for independent validation of the GNSS data products to demonstrate the significant benefits from multi-constellation GNSS in terms of both accuracy and reliability.

  16. Instantaneous Real-Time Kinematic Decimeter-Level Positioning with BeiDou Triple-Frequency Signals over Medium Baselines.

    PubMed

    He, Xiyang; Zhang, Xiaohong; Tang, Long; Liu, Wanke

    2015-01-01

    Many applications, such as marine navigation, land vehicles location, etc., require real time precise positioning under medium or long baseline conditions. In this contribution, we develop a model of real-time kinematic decimeter-level positioning with BeiDou Navigation Satellite System (BDS) triple-frequency signals over medium distances. The ambiguities of two extra-wide-lane (EWL) combinations are fixed first, and then a wide lane (WL) combination is reformed based on the two EWL combinations for positioning. Theoretical analysis and empirical analysis is given of the ambiguity fixing rate and the positioning accuracy of the presented method. The results indicate that the ambiguity fixing rate can be up to more than 98% when using BDS medium baseline observations, which is much higher than that of dual-frequency Hatch-Melbourne-Wübbena (HMW) method. As for positioning accuracy, decimeter level accuracy can be achieved with this method, which is comparable to that of carrier-smoothed code differential positioning method. Signal interruption simulation experiment indicates that the proposed method can realize fast high-precision positioning whereas the carrier-smoothed code differential positioning method needs several hundreds of seconds for obtaining high precision results. We can conclude that a relatively high accuracy and high fixing rate can be achieved for triple-frequency WL method with single-epoch observations, displaying significant advantage comparing to traditional carrier-smoothed code differential positioning method. PMID:26703614

  17. Assessment of the Contribution of BeiDou GEO, IGSO, and MEO Satellites to PPP in Asia-Pacific Region.

    PubMed

    Zhao, Qile; Wang, Chen; Guo, Jing; Liu, Xianglin

    2015-01-01

    In contrast to the US Global Positioning System (GPS), the Russian Global Navigation Satellite System (GLONASS) and the European Galileo, the developing Chinese BeiDou satellite navigation system (BDS) consists of not only Medium Earth Orbit (MEO), but also Geostationary Orbit (GEO) as well as Inclined Geosynchronous Orbit (IGSO) satellites. In this study, the Precise Point Positioning (PPP) and PPP with Integer Ambiguity Resolution (IAR) are obtained. The contributions of these three different types of BDS satellites to PPP in Asia-Pacific region are assessed using data from selected 20 sites over more than four weeks. By using various PPP cases with different satellite combinations, in general, the largest contribution of BDS IGSO among the three kinds of BDS satellites to the reduction of convergence time and the improvement of positioning accuracy, particularly in the east direction, is identified. These PPP cases include static BDS only solutions and static/kinematic ambiguity-float and -fixed PPP with the combination of GPS and BDS. The statistical results demonstrate that the inclusion of BDS GEO and MEO satellites can improve the observation condition and result in better PPP performance as well. When combined with GPS, the contribution of BDS to the reduction of convergence time is, however, not as significant as that of GLONASS. As far as the positioning accuracy is concerned, GLONASS improves the accuracy in vertical component more than BDS does, whereas similar improvement in horizontal component can be achieved by inclusion of BDS IGSO and MEO as GLONASS. PMID:26633406

  18. Assessment of the Contribution of BeiDou GEO, IGSO, and MEO Satellites to PPP in Asia–Pacific Region

    PubMed Central

    Zhao, Qile; Wang, Chen; Guo, Jing; Liu, Xianglin

    2015-01-01

    In contrast to the US Global Positioning System (GPS), the Russian Global Navigation Satellite System (GLONASS) and the European Galileo, the developing Chinese BeiDou satellite navigation system (BDS) consists of not only Medium Earth Orbit (MEO), but also Geostationary Orbit (GEO) as well as Inclined Geosynchronous Orbit (IGSO) satellites. In this study, the Precise Point Positioning (PPP) and PPP with Integer Ambiguity Resolution (IAR) are obtained. The contributions of these three different types of BDS satellites to PPP in Asia–Pacific region are assessed using data from selected 20 sites over more than four weeks. By using various PPP cases with different satellite combinations, in general, the largest contribution of BDS IGSO among the three kinds of BDS satellites to the reduction of convergence time and the improvement of positioning accuracy, particularly in the east direction, is identified. These PPP cases include static BDS only solutions and static/kinematic ambiguity-float and -fixed PPP with the combination of GPS and BDS. The statistical results demonstrate that the inclusion of BDS GEO and MEO satellites can improve the observation condition and result in better PPP performance as well. When combined with GPS, the contribution of BDS to the reduction of convergence time is, however, not as significant as that of GLONASS. As far as the positioning accuracy is concerned, GLONASS improves the accuracy in vertical component more than BDS does, whereas similar improvement in horizontal component can be achieved by inclusion of BDS IGSO and MEO as GLONASS. PMID:26633406

  19. Analysis of BeiDou Satellite Measurements with Code Multipath and Geometry-Free Ionosphere-Free Combinations

    PubMed Central

    Zhao, Qile; Wang, Guangxing; Liu, Zhizhao; Hu, Zhigang; Dai, Zhiqiang; Liu, Jingnan

    2016-01-01

    Using GNSS observable from some stations in the Asia-Pacific area, the carrier-to-noise ratio (CNR) and multipath combinations of BeiDou Navigation Satellite System (BDS), as well as their variations with time and/or elevation were investigated and compared with those of GPS and Galileo. Provided the same elevation, the CNR of B1 observables is the lowest among the three BDS frequencies, while B3 is the highest. The code multipath combinations of BDS inclined geosynchronous orbit (IGSO) and medium Earth orbit (MEO) satellites are remarkably correlated with elevation, and the systematic “V” shape trends could be eliminated through between-station-differencing or modeling correction. Daily periodicity was found in the geometry-free ionosphere-free (GFIF) combinations of both BDS geostationary Earth orbit (GEO) and IGSO satellites. The variation range of carrier phase GFIF combinations of GEO satellites is −2.0 to 2.0 cm. The periodicity of carrier phase GFIF combination could be significantly mitigated through between-station differencing. Carrier phase GFIF combinations of BDS GEO and IGSO satellites might also contain delays related to satellites. Cross-correlation suggests that the GFIF combinations’ time series of some GEO satellites might vary according to their relative geometries with the sun. PMID:26805831

  20. Analysis of BeiDou Satellite Measurements with Code Multipath and Geometry-Free Ionosphere-Free Combinations.

    PubMed

    Zhao, Qile; Wang, Guangxing; Liu, Zhizhao; Hu, Zhigang; Dai, Zhiqiang; Liu, Jingnan

    2016-01-01

    Using GNSS observable from some stations in the Asia-Pacific area, the carrier-to-noise ratio (CNR) and multipath combinations of BeiDou Navigation Satellite System (BDS), as well as their variations with time and/or elevation were investigated and compared with those of GPS and Galileo. Provided the same elevation, the CNR of B1 observables is the lowest among the three BDS frequencies, while B3 is the highest. The code multipath combinations of BDS inclined geosynchronous orbit (IGSO) and medium Earth orbit (MEO) satellites are remarkably correlated with elevation, and the systematic "V" shape trends could be eliminated through between-station-differencing or modeling correction. Daily periodicity was found in the geometry-free ionosphere-free (GFIF) combinations of both BDS geostationary Earth orbit (GEO) and IGSO satellites. The variation range of carrier phase GFIF combinations of GEO satellites is -2.0 to 2.0 cm. The periodicity of carrier phase GFIF combination could be significantly mitigated through between-station differencing. Carrier phase GFIF combinations of BDS GEO and IGSO satellites might also contain delays related to satellites. Cross-correlation suggests that the GFIF combinations' time series of some GEO satellites might vary according to their relative geometries with the sun. PMID:26805831

  1. Instantaneous Real-Time Kinematic Decimeter-Level Positioning with BeiDou Triple-Frequency Signals over Medium Baselines

    PubMed Central

    He, Xiyang; Zhang, Xiaohong; Tang, Long; Liu, Wanke

    2015-01-01

    Many applications, such as marine navigation, land vehicles location, etc., require real time precise positioning under medium or long baseline conditions. In this contribution, we develop a model of real-time kinematic decimeter-level positioning with BeiDou Navigation Satellite System (BDS) triple-frequency signals over medium distances. The ambiguities of two extra-wide-lane (EWL) combinations are fixed first, and then a wide lane (WL) combination is reformed based on the two EWL combinations for positioning. Theoretical analysis and empirical analysis is given of the ambiguity fixing rate and the positioning accuracy of the presented method. The results indicate that the ambiguity fixing rate can be up to more than 98% when using BDS medium baseline observations, which is much higher than that of dual-frequency Hatch-Melbourne-Wübbena (HMW) method. As for positioning accuracy, decimeter level accuracy can be achieved with this method, which is comparable to that of carrier-smoothed code differential positioning method. Signal interruption simulation experiment indicates that the proposed method can realize fast high-precision positioning whereas the carrier-smoothed code differential positioning method needs several hundreds of seconds for obtaining high precision results. We can conclude that a relatively high accuracy and high fixing rate can be achieved for triple-frequency WL method with single-epoch observations, displaying significant advantage comparing to traditional carrier-smoothed code differential positioning method. PMID:26703614

  2. Mitigating BeiDou Satellite-Induced Code Bias: Taking into Account the Stochastic Model of Corrections.

    PubMed

    Guo, Fei; Li, Xin; Liu, Wanke

    2016-01-01

    The BeiDou satellite-induced code biases have been confirmed to be orbit type-, frequency-, and elevation-dependent. Such code-phase divergences (code bias variations) severely affect absolute precise applications which use code measurements. To reduce their adverse effects, an improved correction model is proposed in this paper. Different from the model proposed by Wanninger and Beer (2015), more datasets (a time span of almost two years) were used to produce the correction values. More importantly, the stochastic information, i.e., the precision indexes, were given together with correction values in the improved model. However, only correction values were given while the precision indexes were completely missing in the traditional model. With the improved correction model, users may have a better understanding of their corrections, especially the uncertainty of corrections. Thus, it is helpful for refining the stochastic model of code observations. Validation tests in precise point positioning (PPP) reveal that a proper stochastic model is critical. The actual precision of the corrected code observations can be reflected in a more objective manner if the stochastic model of the corrections is taken into account. As a consequence, PPP solutions with the improved model outperforms the traditional one in terms of positioning accuracy, as well as convergence speed. In addition, the Melbourne-Wübbena (MW) combination which serves for ambiguity fixing were verified as well. The uncorrected MW values show strong systematic variations with an amplitude of half a wide-lane cycle, which prevents precise ambiguity determination and successful ambiguity resolution. After application of the code bias correction models, the systematic variations can be greatly removed, and the resulting wide lane ambiguities are more likely to be fixed. Moreover, the code residuals show more reasonable distributions after code bias corrections with either the traditional or the improved model

  3. Mitigating BeiDou Satellite-Induced Code Bias: Taking into Account the Stochastic Model of Corrections

    PubMed Central

    Guo, Fei; Li, Xin; Liu, Wanke

    2016-01-01

    The BeiDou satellite-induced code biases have been confirmed to be orbit type-, frequency-, and elevation-dependent. Such code-phase divergences (code bias variations) severely affect absolute precise applications which use code measurements. To reduce their adverse effects, an improved correction model is proposed in this paper. Different from the model proposed by Wanninger and Beer (2015), more datasets (a time span of almost two years) were used to produce the correction values. More importantly, the stochastic information, i.e., the precision indexes, were given together with correction values in the improved model. However, only correction values were given while the precision indexes were completely missing in the traditional model. With the improved correction model, users may have a better understanding of their corrections, especially the uncertainty of corrections. Thus, it is helpful for refining the stochastic model of code observations. Validation tests in precise point positioning (PPP) reveal that a proper stochastic model is critical. The actual precision of the corrected code observations can be reflected in a more objective manner if the stochastic model of the corrections is taken into account. As a consequence, PPP solutions with the improved model outperforms the traditional one in terms of positioning accuracy, as well as convergence speed. In addition, the Melbourne-Wübbena (MW) combination which serves for ambiguity fixing were verified as well. The uncorrected MW values show strong systematic variations with an amplitude of half a wide-lane cycle, which prevents precise ambiguity determination and successful ambiguity resolution. After application of the code bias correction models, the systematic variations can be greatly removed, and the resulting wide lane ambiguities are more likely to be fixed. Moreover, the code residuals show more reasonable distributions after code bias corrections with either the traditional or the improved model

  4. Analysis on the long-term dynamical evolution of the inclined geosynchronous orbits in the Chinese BeiDou navigation system

    NASA Astrophysics Data System (ADS)

    Zhao, Chang-Yin; Zhang, Ming-Jiang; Wang, Hong-Bo; Xiong, Jian-Ning; Zhu, Ting-Lei; Zhang, Wei

    2015-08-01

    Five inclined geosynchronous orbit (IGSO) satellites with the inclination of about 55° in the Chinese BeiDou navigation system have been put in orbit until now. The Inter-Agency Space Debris Coordination Committee (IADC) has defined a geosynchronous orbit (GEO) protected region and recommended that the GEO satellite should be maneuvered to a disposal orbit high enough at end-of-mission to remain above the GEO protected region. The recommended disposal altitude is at least 235 km + (1000 ·CR · A / M) higher than the perigee altitude of the GEO satellite, where CR and A / M are radiation pressure coefficient and area-to-mass ratio respectively. Whether this recommendation is also adequate for the disposal of these IGSO satellites in the Chinese BeiDou navigation system at end-of-mission? And if not, is there any other possible strategy to do? In view of these considerations, the long-term dynamical evolution of these IGSO satellites is investigated by both theoretical analysis and numerical computation methods in this paper. Some qualitative orbital evolution characteristics and quantitative result of variation ranges of the semi-major axis a, the inclination i and the eccentricity e are presented respectively. Based on these results, a possible mitigation strategy to reduce the orbital lifetime of the IGSO satellites after end-of-mission is proposed.

  5. Assessment of precipitable water vapor derived from ground-based BeiDou observations with Precise Point Positioning approach

    NASA Astrophysics Data System (ADS)

    Li, Min; Li, Wenwen; Shi, Chuang; Zhao, Qile; Su, Xing; Qu, Lizhong; Liu, Zhizhao

    2015-01-01

    Precipitable water vapor (PWV) estimation from Global Positioning System (GPS) has been extensively studied and used for meteorological applications. However PWV estimation using the emerging BeiDou Navigation Satellite System (BDS) is very limited. In this paper the PWV estimation strategy and the evaluation of the results inferred from ground-based BDS observations using Precise Point Positioning (PPP) method are presented. BDS and GPS data from 10 stations distributed in the Asia-Pacific and West Indian Ocean regions during the year 2013 are processed using the PANDA (Position and Navigation Data Analyst) software package. The BDS-PWV and GPS-PWV are derived from the BDS-only and GPS-only observations, respectively. The PPP positioning differences between BDS-only and GPS-only show a standard deviation (STD) <1 cm in the east and north components and 1-3 cm in vertical component. The BDS-PWV and GPS-PWV at the HKTU station (Hong Kong, China) is compared with PWV derived from a radiosonde station (about 1 km distance) over a 6-month period. The GPS-PWV shows a good agreement with radiosonde-PWV with a bias of 0.002 mm and a STD of 2.49 mm while BDS-PWV has with a bias of -2.04 mm and STD 2.68 mm with respect to radiosonde-PWV. This indicates that the PWV estimated from the BDS can achieve similar precision as PWV from GPS. The BDS-PWV is compared to GPS-PWV at 10 stations. The mean bias and STD of their differences at 10 stations are 0.78 mm and 1.77 mm, respectively. The mean root mean square (RMS) value is 2.00 mm by considering the GPS-PWV as reference truth. This again confirms that the BDS-PWV has a good agreement with the GPS-PWV. It clearly indicates that the BDS is ready for the high precision meteorological applications in the Asia-Pacific and West Indian Ocean regions and that BDS alone can be used for PWV estimation with an accuracy comparable to GPS.

  6. BeiDou phase bias estimation and its application in precise point positioning with triple-frequency observable

    NASA Astrophysics Data System (ADS)

    Gu, Shengfeng; Lou, Yidong; Shi, Chuang; Liu, Jingnan

    2015-10-01

    At present, the BeiDou system (BDS) enables the practical application of triple-frequency observable in the Asia-Pacific region, of many possible benefits from the additional signal; this study focuses on exploiting the contribution of zero difference (ZD) ambiguity resolution (AR) to the precise point positioning (PPP). A general modeling strategy for multi-frequency PPP AR is presented, in which, the least squares ambiguity decorrelation adjustment (LAMBDA) method is employed in ambiguity fixing based on the full variance-covariance ambiguity matrix generated from the raw data processing model. Because of the reliable fixing of BDS L1 ambiguity faces more difficulty, the LAMBDA method with partial ambiguity fixing is proposed to enable the independent and instantaneous resolution of extra wide-lane (EWL) and wide-lane (WL). This mechanism of sequential ambiguity fixing is demonstrated for resolving ZD satellite phase bias and performing triple-frequency PPP AR with two reference station networks with a typical baseline of up to 400 and 800 km, respectively. Tests show that about of the EWL and WL phase bias of BDS has a consistency of better than 0.1 cycle, and this value decreases to 80 % for L1 phase bias for Experiment I, while all the solutions of Experiment II have a similar RMS of about 0.12 cycles. In addition, the repeatability of the daily mean phase bias agree to 0.093 cycles and 0.095 cycles for EWL and WL on average, which is much smaller than 0.20 cycles of L1. To assess the improvement of fixed PPP brought by applying the third frequency signal as well as the above phase bias, various ambiguity fixing strategy are considered in the numerical demonstration. It is shown that the impact of the additional signal is almost negligible when only float solution involved. It is also shown that by fixing EWL and WL together, as opposed to the single ambiguity fixing, will leads to an improvement in PPP accuracy by about on average. Attributed to the efficient

  7. Comprehensive Comparisons of Satellite Data, Signals, and Measurements between the BeiDou Navigation Satellite System and the Global Positioning System.

    PubMed

    Jan, Shau-Shiun; Tao, An-Lin

    2016-01-01

    The Chinese BeiDou navigation satellite system (BDS) aims to provide global positioning service by 2020. The combined use of BDS and Global Positioning System (GPS) is proposed to provide navigation service with more stringent requirements. Actual satellite data, signals and measurements were collected for more than one month to analyze the positioning service qualities from both BDS and GPS. In addition to the conversions of coordinate and timing system, five data quality analysis (DQA) methods, three signal quality analysis (SQA) methods, and four measurement quality analysis (MQA) methods are proposed in this paper to improve the integrated positioning performance of BDS and GPS. As shown in the experiment results, issues related to BDS and GPS are resolved by the above proposed quality analysis methods. Thus, the anomalies in satellite data, signals and measurements can be detected by following the suggested resolutions to enhance the positioning performance of the combined use of BDS and GPS in the Asia Pacific region. PMID:27187403

  8. Comprehensive Comparisons of Satellite Data, Signals, and Measurements between the BeiDou Navigation Satellite System and the Global Positioning System †

    PubMed Central

    Jan, Shau-Shiun; Tao, An-Lin

    2016-01-01

    The Chinese BeiDou navigation satellite system (BDS) aims to provide global positioning service by 2020. The combined use of BDS and Global Positioning System (GPS) is proposed to provide navigation service with more stringent requirements. Actual satellite data, signals and measurements were collected for more than one month to analyze the positioning service qualities from both BDS and GPS. In addition to the conversions of coordinate and timing system, five data quality analysis (DQA) methods, three signal quality analysis (SQA) methods, and four measurement quality analysis (MQA) methods are proposed in this paper to improve the integrated positioning performance of BDS and GPS. As shown in the experiment results, issues related to BDS and GPS are resolved by the above proposed quality analysis methods. Thus, the anomalies in satellite data, signals and measurements can be detected by following the suggested resolutions to enhance the positioning performance of the combined use of BDS and GPS in the Asia Pacific region. PMID:27187403

  9. The open service signal in space navigation data comparison of the Global Positioning System and the BeiDou Navigation Satellite System.

    PubMed

    Jan, Shau-Shiun; Tao, An-Lin

    2014-01-01

    More and more Global Navigation Satellite Systems (GNSSs) have been developed and are in operation. Before integrating information on various GNSSs, the differences between the various systems must be studied first. This research focuses on analyzing the navigation data differences between the Chinese BeiDou Navigation Satellite System (BDS) and the United States' Global Positioning System (GPS). In addition to explaining the impact caused by these two different coordinate and time systems, this research uses an actual open service signal in space (SIS) for both GPS and BDS to analyze their current system performance. Five data quality analysis (DQA) mechanisms are proposed in this research to validate both systems' SIS navigation data. These five DQAs evaluate the differences in ephemeris and almanac messages from both systems for stability and accuracy. After all of the DQAs, the different issues related to GPS and BDS satellite information are presented. Finally, based on these DQA results, this research provides suggested resolutions for the combined use of GPS and BDS for navigation and guidance. PMID:25195848

  10. The Open Service Signal in Space Navigation Data Comparison of the Global Positioning System and the BeiDou Navigation Satellite System

    PubMed Central

    Jan, Shau-Shiun; Tao, An-Lin

    2014-01-01

    More and more Global Navigation Satellite Systems (GNSSs) have been developed and are in operation. Before integrating information on various GNSSs, the differences between the various systems must be studied first. This research focuses on analyzing the navigation data differences between the Chinese BeiDou Navigation Satellite System (BDS) and the United States' Global Positioning System (GPS). In addition to explaining the impact caused by these two different coordinate and time systems, this research uses an actual open service signal in space (SIS) for both GPS and BDS to analyze their current system performance. Five data quality analysis (DQA) mechanisms are proposed in this research to validate both systems' SIS navigation data. These five DQAs evaluate the differences in ephemeris and almanac messages from both systems for stability and accuracy. After all of the DQAs, the different issues related to GPS and BDS satellite information are presented. Finally, based on these DQA results, this research provides suggested resolutions for the combined use of GPS and BDS for navigation and guidance. PMID:25195848

  11. Real-Time seismic waveforms monitoring with BeiDou Navigation Satellite System (BDS) observations for the 2015 Mw 7.8 Nepal earthquake

    NASA Astrophysics Data System (ADS)

    Geng, T.

    2015-12-01

    Nowadays more and more high-rate Global Navigation Satellite Systems (GNSS) data become available in real time, which provide more opportunities to monitor the seismic waveforms. China's GNSS, BeiDou Navigation Satellite System (BDS), has already satisfied the requirement of stand-alone precise positioning in Asia-Pacific region with 14 in-orbit satellites, which promisingly suggests that BDS could be applied to the high-precision earthquake monitoring as GPS. In the present paper, real-time monitoring of seismic waveforms using BDS measurements is assessed. We investigate a so-called "variometric" approach to measure real-time seismic waveforms with high-rate BDS observations. This approach is based on time difference technique and standard broadcast products which are routinely available in real time. The 1HZ BDS data recorded by Beidou Experimental Tracking Stations (BETS) during the 2015 Mw 7.8 Nepal earthquake is analyzed. The results indicate that the accuracies of velocity estimation from BDS are 2-3 mm/s in horizontal components and 8-9 mm/s in vertical component, respectively, which are consistent with GPS. The seismic velocity waveforms during earthquake show good agreement between BDS and GPS. Moreover, the displacement waveforms is reconstructed by an integration of velocity time series with trend removal. The displacement waveforms with the accuracy of 1-2 cm are derived by comparing with post-processing GPS precise point positioning (PPP).

  12. Unverstandene Horaz-Zitate bei Nicolaus Copernicus.

    NASA Astrophysics Data System (ADS)

    Krafft, F.

    Being a Renaissance Humanist, Copernicus takes care to demonstrate his education also by quotations from classical authors which however are concealed in a way that they are recognized and understood in their meaning only by equally educated persons. Three such quotations from the Ars poetica by Horace are represented. These not only enable completely new insights into the dating of certain phases of his writing the main work De revolutionibus (especially book III) but also mark his characterization of "good" and "bad" astronomers (and astronomies). Furthermore they give evidence that T.S. Kuhn's "Structure of Scientific Revolutions" cannot apply to the Copernican turning point of astronomy called revolution.

  13. Mensch-Maschine-Interaktion bei Fahrerassistenzsystemen

    NASA Astrophysics Data System (ADS)

    Reif, Konrad

    Der Autofahrer muss eine ständig wachsende Flut von Informationen verarbeiten, die vom eigenen und von fremden Fahrzeugen, von der Straße und über Tele kommunikationseinrichtungen auf ihn einwirken. Diese Informationen müssen ihm mit geeigneten Anzeigemedien und unter Beachtung ergonomischer Erfor dernisse übermittelt werden.

  14. Hydrogen-bonded ring closing and opening of protonated methanol clusters H(+)(CH3OH)(n) (n = 4-8) with the inert gas tagging.

    PubMed

    Li, Ying-Cheng; Hamashima, Toru; Yamazaki, Ryoko; Kobayashi, Tomohiro; Suzuki, Yuta; Mizuse, Kenta; Fujii, Asuka; Kuo, Jer-Lai

    2015-09-14

    The preferential hydrogen bond (H-bond) structures of protonated methanol clusters, H(+)(MeOH)n, in the size range of n = 4-8, were studied by size-selective infrared (IR) spectroscopy in conjunction with density functional theory calculations. The IR spectra of bare clusters were compared with those with the inert gas tagging by Ar, Ne, and N2, and remarkable changes in the isomer distribution with the tagging were found for clusters with n≥ 5. The temperature dependence of the isomer distribution of the clusters was calculated by the quantum harmonic superposition approach. The observed spectral changes with the tagging were well interpreted by the fall of the cluster temperature with the tagging, which causes the transfer of the isomer distribution from the open and flexible H-bond network types to the closed and rigid ones. Anomalous isomer distribution with the tagging, which has been recently found for protonated water clusters, was also found for H(+)(MeOH)5. The origin of the anomaly was examined by the experiments on its carrier gas dependence. PMID:26235389

  15. Romanistik ohne Latein? Zu einer Empfehlung der Konferenz der Romanischen Seminare (Romance Studies without Latin? On a Recommendation from the Conference of Romance Seminars)

    ERIC Educational Resources Information Center

    Neumeister, Sebastian

    1973-01-01

    Reaction to a February 19, 1972 recommendation of the Konferenz der Romanischen Seminare der Bundesrepublik Deutschland und West-Berlins in Deutschen Romanistenverband'' (Conference of Romance Seminars of the Federal Republic of Germany and West Berlin of the German Association of Romance Philologists) to discontinue the Latin prerequisite for…

  16. „Überholen ohne einzuholen“ Die Entwicklung von Technologien für übermorgen in Kernenergie und Mikroelektronik der DDR

    NASA Astrophysics Data System (ADS)

    Barkleit, Gerhard

    Dem nuklearen Patt zwischen Ostblock und westlichem Staatenbündnis ist es nach weitgehend übereinstimmender Auffassung von Politik und Wissenschaft zu danken, dass der "Kalte Krieg" in der zweiten Hälfte des 20. Jahrhunderts nicht zum weltumfassenden Flächenbrand eskalierte. An der raschen Herstellung dieses Patts waren zwei Dresdner Physiker maßgeblich beteiligt, deren einer im Manhattan-Projekt in den USA gearbeitet hatte und später in England der Spionage für die Sowjetunion und des Verrats des Know-how der Atombombe überführt wurde.

  17. Transporterscheinungen

    NASA Astrophysics Data System (ADS)

    Heintze, Joachim

    In diesem Kapitel werden wir uns vornehmlich mit zwei Vorgängen befassen, ohne die das Erreichen des thermischen Gleichgewichts und die Veränderung des thermischen Zustands eines Systems unmöglich wäre: Wärmeleitung und Diffusion. Bei der Wärmeleitung wird die kinetische Energie der Teilchen durch Stöße auf die Nachbarn übertragen: Es handelt sich um den Transport von Wärmeenergie. Unter Diffusion versteht man den Transport von Molekülen aufgrund ihrer Wärmebewegung. Sie tritt in Erscheinung, wenn in einem System verschiedene Arten von Molekülen vorhanden und ungleichmäßig verteilt sind.

  18. Bei: Intraclausal Coherence Relations Illustrated with a German Preposition

    ERIC Educational Resources Information Center

    Grabski, Michael; Stede, Manfred

    2006-01-01

    Coherence relations are typically taken to link two clauses or larger units and to be signaled at the text surface by conjunctions and certain adverbials. Relations, however, also can hold within clauses, indicated by prepositions like despite, due to, or in case of, when these have an internal argument denoting an eventuality. Although these…

  19. 78 FR 16680 - Shu Bei Yuan: Debarment Order

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-18

    .... The purpose of Ms. Yuan's scheme was to import, enter, and sell Chinese-origin honey into the United... Homeland Security, Bureau of Customs and Border Protection (CBP) that the imported honey originated from countries other than China, including South Korea, when in fact Ms. Yuan knew that the honey originated...

  20. Physik im Beruf Physiker bei der Deutschen Börse

    NASA Astrophysics Data System (ADS)

    Schäfer, Carsten

    2002-01-01

    Seine wissenschaftlichen Wirkungsstätten sind schnell aufgezählt: Basel, St. Petersburg, Berlin. Und wieder St. Petersburg. Mit seiner Arbeit ist das schon schwieriger.Insgesamt zählt man ungefähr 900 Arbeiten und zwanzig Bücher aus seiner Feder.

  1. Radio occultation based on BeiDou satellite navigation

    NASA Astrophysics Data System (ADS)

    Jiang, Hu; Hu, Haiying; Shen, Xue-min; Gong, Wenbin; Zhang, Yonghe

    2014-11-01

    With the development of GNSS systems, it has become a tendency that radio occultation is used to sense the Earth's atmosphere. By this means, the moisture, temperature, pressure, and total electron content can be derived. Based on the sensing results, more complicated models for atmosphere might come into being. Meteorology well benefits from this technology. As scheduled, the BD satellite navigation system will have a worldwide coverage by the end of 2020. Radio occultation studies in China have been highlighted in the recent decade. More and more feasibilities reports have been published in either domestic or international journals. Herein, some scenarios are proposed to assess the coverage of radio occultation based on two different phases of BD satellite navigation system. Phase one for BD is composed of GEO,IGSO and several MEO satellites. Phase two for BD consists mostly of 24 MEO satellites, some GEO and IGSO satellites. The characteristics of radio occultation based on these two phases are presented respectively.

  2. Untersuchungen zur Regeneration des Hinterendes bei Anaitides mucosa (Polychaeta, Phyllodocidae)

    NASA Astrophysics Data System (ADS)

    Röhrkasten, A.

    1983-06-01

    Caudal regeneration was investigated in decerebrate Anaitides mucosa and in brain-intact individuals. Both groups show an identical capacity to regenerate lost caudal segments. Furthermore there is no difference in males and females. Low temperature (5 °C) inhibits the regeneration of caudal segments, but it is necessary for normal oogenesis. Under conditions of high temperature (15 °C), caudal regeneration is very extensive. At the same time degeneration of most oocytes occurs.

  3. Quantitative Analyse der Korallenbesiedlung eines Vorriffareals bei Aqaba (Rotes Meer)

    NASA Astrophysics Data System (ADS)

    Mergner, H.; Schuhmacher, H.

    1981-09-01

    Previous descriptions of the ecology and zonation of Aqaba reefs (Mergner & Schuhmacher, 1974) are supplemented by this quantitative study of a test quadrat (5×5 m in size), randomly chosen in some 10 m depth in the middle fore reef of a coastal fringing reef. Of the total surface of 25 m2 Cnidaria represent 42.31%, sponges 0.17%, calcareous algae 0.20%, dead coral rock and pebble 30.27% and sand and coral debris 26.15%. The cnidarian cover is roughly equally contributed by 50.86% Scleractinia and 48.61% Alcyonaria, mainly Xeniidae (35.81%). For each species the percentage of the total cover (measured as vertical projection), colony number, average and maximal colony size are given. A total number of 104 cnidarian species was recorded, among which the 78 scleractinian species represent 34 of the 55 coral genera known from the Red Sea. The well balanced regime of moderate light and current conditions which are tolerated both by shallow and deep water species may account for the high species number. Disturbances such as occasional sedimentation, grazing of sea urchins (Diadema setosum) and overgrowth of stony corals by xeniids result in continuous fluctuations of the coral community, in small colony size and in high colony number. Abiotic factors and biotic interactions maintain a diversity (H=3.67) which ranks among the greatest ever found in reef communities. The data obtained from the fore reef square are compared with those of a similar test square in the lagoon of the same reef and with results from transect zonations on the opposite coast of the Gulf of Aqaba. These comparisons indicate that the fore reef harbours the richest coral fauna in the reef. The inventory of coral species at the northern end of the Gulf of Aqaba, one of the northernmost outposts of the coral reef belt, is only little reduced when compared with that of the central Red Sea; this great species diversity is in contrast to the worldwide decrease of species number towards the periphery of the reef belt.

  4. Sexuelle Fortpflanzung bei der braunen Krustenalge Pseudolithoderma extensum

    NASA Astrophysics Data System (ADS)

    Peters, Akira F.

    1989-06-01

    Reproduction was studied in Pseudolithoderma extensum (Crouan et Crouan) Lund (Lithodermataceae, Phaeophyceae) from Helgoland. Both gametophytes and sporophytes are crustose. Fertile gametophytes were found in nature in January and February. They released motile isogametes from plurilocular gametangia, each gamete leaving its locule through a separate opening. Plasmogamy was observed directly under the microscope. In laboratory culture, zygotes developed to crustose thalli, whereas unfused gametes died soon after germination. Sporophytes were found in nature with fertile unilocular sporangia in March. In culture, zoospores released from these sporangia also developed to crusts. Kuckuck’s observation at the beginning of the century (1912a) that P. extensum exhibits an alternation of isomorphic generations and isogamy is thus confirmed.

  5. Evolutionstheorie als Geschichtstheorie - Ein neuer Ansatz historischer Institutionenforschung

    NASA Astrophysics Data System (ADS)

    Patzelt, Werner J.

    Werden und Vergehen kennzeichnen die Natur. Dass Einzelwesen geboren werden, reifen, altern und sterben, lernen schon Kinder. Dass auch Arten, einschließlich der des Menschen, entstehen und vergehen, gerät während der Schulzeit ins Blickfeld. Erwachsene begreifen dann, dass Individuen gleichsam die Träger und "Realisatoren“ des Bauplans einer Art sind: Als solche werden sie gezeugt, als solche tragen sie ihre Art während der eigenen Lebensspanne, als solche geben viele den ihnen eingeschriebenen Bauplan an Nachfolger weiter, und all dies leistend wirken Einzelwesen wie "Durchlaufposten“ ihrer Art. Diese besteht zwar nie ohne ihre Individuen; doch meist kommt es auf kein einzelnes Lebewesen als solches an, um dessen Art fortbestehen zu lassen. Zu verdanken ist der Wandel einer Art mancherlei Veränderungen (z. B. Variationen, Rekombinationen) bei der Weitergabe des Bauplans von Individuum zu Individuum, desgleichen den Besonderheiten einer je konkreten Realisierung des allgemeinen Bauplans einer Art unter spezifischen Umständen. Durchsetzungskraft, weitere Verbreitung und somit Dauerhaftigkeit ("Mutation“) erlangt solcher Wandel dann, wenn die bei der Weitergabe unterlaufenen Veränderungen und die von der Umwelt oder der ökologischen Nische einem Individuum oder einer Gruppe von Individuen aufgezwungenen Variationen ihrerseits Weitergabevorteile bei der Reproduktion des Bauplans eröffnen. Die individueller Veränderung geschuldete Ausnahme mag dann nach einigen Generationen sogar der Normalfall geworden sein. Umwelt ist dabei alles, was ein Individuum oder eine Art umgibt. Die "ökologische Nische“ ist hingegen jener Teil der Umwelt, welcher für das Individuum oder die Art unmittelbar wichtig ist, vor allem weil aus ihr die nötigen Ressourcen bezogen werden oder in ihr die Auseinandersetzung mit Konkurrenten zu bestehen ist.

  6. Dünne Beschichtungen auf Biomaterialien

    NASA Astrophysics Data System (ADS)

    Klee, Doris; Lahann, Jörg; Plüster, Wilhelm

    Ein Schwerpunkt der Implantatentwicklung liegt in der Synthese und Verarbeitung geeigneter Biomaterialien, die bezüglich ihrer mechanischen Eigenschaften und ihrer Stabilität die erwünschte Funktion im Organismus erfüllen sollen. Die biologische Antwort auf Biomaterialien im Implantateinsatz wird jedoch hauptsächlich von der chemischen Zusammensetzung und der Struktur der Implantatoberfläche bestimmt [1]. Sie ist entscheidend für die Langzeitverträglichkeit eines Implantats. Geeignete Ansätze zur Verbesserung der Grenzflächenverträglichkeit von Biomaterialien, ohne die mechanischen Eigenschaften und die Funktionalität des Implantates zu verändern, beruhen auf die Aufbringung einer definierten, falls erforderlich biologisch aktiven Beschichtung auf die Werkstoffoberfläche. Bei den eingesetzten Beschichtungsverfahren handelt es sich vielfach um bekannte Verfahren zur Oberflächenmodifizierung technischer Werkstoffe, die auf physikalischen und chemischen Prozessen basieren. Je nach Beschichtungsverfahren können unterschiedliche Schichtdicken erzielt werden. Zur Charakterisierung der Zusammensetzung und Struktur der beschichteten Biomaterialoberflächen ist der Einsatz oberflächensensitiver Analytik unverzichtbar. Vielfach wird eine Kombination von Methoden eingesetzt, die sich hinsichtlich ihrer Informationstiefe und Informationsaussage unterscheiden [1].

  7. IntegraTUM Teilprojekt E-Mail: Aufbau eines mandantenfähigen Groupware-Services und seine Integration in Identity Management und E-Mail Infrastruktur der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Diehn, Max

    Die E-Mail-Infrastruktur an der Technischen Universität München (TUM) ist historisch bedingt sehr heterogen und komplex. Viele Einrichtungen müssen wertvolle Arbeitskraft auf die Administration eigener Mailserver verwenden. Auf der anderen Seite wird bei einigen Einrichtungen der Ruf nach Groupware-Funktionalitäten wie z.B. gemeinsame Kalender immer lauter. Das Teilprojekt E-Mail stellt einen zentralen Mail- und Groupware-Service bereit, der den Einrichtungen ermöglichen soll, den Betrieb eigener Server und zugehöriger Systeme (etwa lokaler Benutzerverwaltungen) für diesen Zweck aufzugeben und diese Dienste an das Teilprojekt E-Mail zu migrieren, ohne ihre Verwaltungshoheit oder ihre Maildomains aufgeben zu müssen. Dieser Service versteht sich als eine Ergänzung zur bestehenden Grundversorgung der TUM mit den Maildiensten des myTUM-Mailers, ist mandantenfähig aufgebaut und kann daher künftig neben der TUM auch weiteren Organisationen im Münchner Wissenschaftsnetz zur Verfügung gestellt werden.

  8. Echtzeit-Ultraschallsimulation auf Grafik-Prozessoren mit CUDA

    NASA Astrophysics Data System (ADS)

    Reichl, Tobias; Passenger, Josh; Acosta, Oscar; Salvado, Olivier

    Trotz der zunehmenden Verbreitung jüngerer bildgebender Verfahren bleibt medizinischer Ultraschall (US) weiterhin ein wichtiges Hilfsmittel bei chirurgischen Eingriffen und der klinischen Diagnose. Viele US-gestützte medizinische Prozeduren erfordern allerdings ausgiebiges Training, so dass es wünschenswert ist, eine realistische Simulation von US-Bildern zur Verfügung zu stellen. Im Gegensatz zu früheren Ansätzen simulieren wir solche Bilder auf der "Graphics Processing Unit“. Wir erweitern hierzu eine Methode, die von Wein et al. für die Abschätzung von US-Reflexionen aus Daten der Computertomographie (CT) vorgeschlagen wurde, zu einer leichter zu berechnenden Form. Zusätzlich schätzen wir die US-Absorption aus den CT-Daten ab. Mit Hilfe von NVIDIAs "Compute Unified Device Architecture“ (CUDA) simulieren wir Reflexion, Verschattung, Rauschen und radiale Unschärfe, ausgehend von unbearbeiteten CT-Daten in Echtzeit und ohne Vorausberechnung.

  9. Phänomenologische Grundlagen der Wärmelehre

    NASA Astrophysics Data System (ADS)

    Heintze, Joachim

    Die Physik der Wärme lässt sich auf zweierlei Weise formulieren: Einmal als Mechanik eines Systems, das eine enorm große Zahl von Teilchen enthält (statistische Mechanik), und einmal mit Hilfe von ad hoc eingeführten Größen, den sogenannten Zustandsgrößen, die geeignet sind, das Verhalten eines solchen Systems zu beschreiben, ohne dass man die Teilchen selbst und ihre Bewegungen betrachten muss (Thermodynamik). Wir werden beide Ansätze in ihrer einfachsten und anschaulichsten Ausprägung in Kap. 5 (kinetische Gastheorie) bzw. in Kap. 8 (Grundbegriffe der Thermodynamik) behandeln. Obgleich sich die volle Durchführung des Programms als begrifflich und mathematisch recht schwierig erweist - die Vorlesung "Thermodynamik und Statistik" steht gewöhnlich am Ende der Kursvorlesungen über theoretische Physik - werden wir doch auf der Grundlage der Kap. 5 und 8 eine Menge über die Physik der Wärme lernen können. Den Ausgangspunkt der Wärmelehre bilden jedoch allemal die Naturerscheinungen, die wir hier in Kap. 4 behandeln wollen: Wärme, Kälte, Temperaturausgleich. Wir werden untersuchen, wie man diese Begriffe quantifizieren kann, und was bei der Erwärmung oder Abkühlung eines Körpers vor sich geht. Dabei werden wir auf den I. und II. Hauptsatz der Wärmelehre stoßen.

  10. ...und Einstein hatte doch recht

    NASA Astrophysics Data System (ADS)

    Will, Clifford M.; Leuchs, Anne; Leuchs, Gerd

    Keine wissenschaftliche Theorie ist auf solche Faszination auch außerhalb der Wissenschaft gestoßen wie die Allgemeine Relativitätstheorie von Albert Einstein, und keine wurde so nachdrücklich mit den Mitteln der modernen Physik überprüft. Wie hat sie diesen Test mit Raumsonden, Radioastronomie, Atomuhren und Supercomputern standgehalten? Hatte Einstein recht? Mit der Autorität des Fachmanns und dem Flair des unvoreingenommenen Erzählers schildert Clifford Will die Menschen, Ideen und Maschinen hinter den Tests der allgemeinen Relativitätstheorie. Ohne Formeln und Fachjargon wird der leser mit Einsteins Gedanken vertraut und erfährt von der Bestätigung seiner Vorhersagen, angefangen bei der Lichtablenkung im Schwerefeld der Sonne 1919 bis zu den ausgefeilten Kreiselexperimenten auf dem Space Shuttle. Die Allgemeine Relativitätstheorie hat nich nur alle diese Tests bestanden, sie hat darüber hinaus wesentlich beigetragen zu unserem Verständnis von Phänomenen wie Pulsaren, Quasaren, Schwarzen Löchern und Gravitationslinsen. Dieses Buch erzählt lebendig und spannend die Geschichte einer der größten geistigen Leistungen unserer Zeit.

  11. Timing group delay and differential code bias corrections for BeiDou positioning

    NASA Astrophysics Data System (ADS)

    Guo, Fei; Zhang, Xiaohong; Wang, Jinling

    2015-05-01

    This article first clearly figures out the relationship between parameters of timing group delay (TGD) and differential code bias (DCB) for BDS, and demonstrates the equivalence of TGD and DCB correction models combining theory with practice. The TGD/DCB correction models have been extended to various occasions for BDS positioning, and such models have been evaluated by real triple-frequency datasets. To test the effectiveness of broadcast TGDs in the navigation message and DCBs provided by the Multi-GNSS Experiment (MGEX), both standard point positioning (SPP) and precise point positioning (PPP) tests are carried out for BDS signals with different schemes. Furthermore, the influence of differential code biases on BDS positioning estimates such as coordinates, receiver clock biases, tropospheric delays and carrier phase ambiguities is investigated comprehensively. Comparative analysis show that the unmodeled differential code biases degrade the performance of BDS SPP by a factor of two or more, whereas the estimates of PPP are subject to varying degrees of influences. For SPP, the accuracy of dual-frequency combinations is slightly worse than that of single-frequency, and they are much more sensitive to the differential code biases, particularly for the B2B3 combination. For PPP, the uncorrected differential code biases are mostly absorbed into the receiver clock bias and carrier phase ambiguities and thus resulting in a much longer convergence time. Even though the influence of the differential code biases could be mitigated over time and comparable positioning accuracy could be achieved after convergence, it is suggested to properly handle with the differential code biases since it is vital for PPP convergence and integer ambiguity resolution.

  12. Die Aufnahme partikulärer Nahrung bei Reniera sp. (Porifera)

    NASA Astrophysics Data System (ADS)

    Langenbruch, Paul-Friedrich

    1985-09-01

    The choanocyte chambers of the marine sponge Reniera sp. protrude with their curved outer surface free into the incurrent canals. The water is sucked into the chambers by cavities between the choanocytes. Particles up to 1 µm in diameter may enter the chambers with the water current. These particles are trapped on the outer surface of the choanocyte collars and are ingested by the choanocytes and processes of the pinacocyte epithelium of the incurrent canal system, which project into the chambers. Bigger particles are retained in the incurrent canals mainly on the outer surface of the choanocyte chambers. They are ingested by pinacocytes of the canal wall and transported to cells of the mesenchyme. The present investigation shows the great importance of the pinacocyte epithelium of the incurrent canal system for suspension feeding in Reniera sp.

  13. Misunderstood citations of Horace by Nicolaus Copernicus. (German Title: Unverstandene Horaz-Zitate bei Nicolaus Copernicus)

    NASA Astrophysics Data System (ADS)

    Krafft, Fritz

    Being a Renaissance humanist, Copernicus takes care to demonstrate his education also by quotations from classical authors which however are concealed in a way that they are recognized and understood in their meaning only by equally educated persons. Three such quotations from the Ars poetica by Horace are represented. These not only enable completely new insights into the dating of certain phases of his writing the main work De revolutionibus (especially book III) but also mark his characterization of 'good' and 'bad' astronomers (and astronomies). Furthermore they give evidence that T.S. Kuhn's ``Structure of Scientific Revolutions'' cannot apply to the Copernican turning point of astronomy called revolution.

  14. "Doch ein Begriff muss bei dem Worte sein": Some Thoughts on Electronically Annotated Literary Texts.

    ERIC Educational Resources Information Center

    Duncan, Bruce; Foelsche, Otmar K. E.

    1995-01-01

    Discusses the use of electronic glossaries, annotated texts, and other ancillae in German-as-a-Second-Language courses at the college level, and asserts that electronic media deliver lexical assistance far more effectively than do traditional methods, using texts in ways previously unavailable. (MDM)

  15. Zur Bedeutung von ausserschulischen Bildungsmassnahmen bei der Arbeitsplatzsuche in zwei brasilianischen Industriezentren

    NASA Astrophysics Data System (ADS)

    Lehmann, Rainer H.; Verhine, Robert E.

    1982-03-01

    In view of the high cost and the often disappointing results achieved by the massive extension of general education in developing countries, this article investigates the extent to which out-of-school education and training courses assist workers in Brazilian industrial centres in obtaining employment. By discriminant analysis, information on the education and training of 149 applicants for industrial jobs in João Pessoa and Salvador is related to the success rate of their applications. It is shown that, while formal school education raises the vocational expectations of the workers in both towns, it does not coincide with a higher probability of securing employment. On the other hand, participation in out-of-school education or training correlates positively with employment opportunities, for different reasons according to the context. In João Pessoa, where industry is only in the early stages of development, programmes which appear to have no direct relation to the hoped-for job seem to be as useful in the search for employment as specific professional training courses. This indicates the economic importance of participation in out-of-school courses. In Salvador, however, which is economically more highly developed, out-of-school vocational training alone appears to have a positive influence on the chances of finding employment. Apparently, decision criteria here are oriented more to consideration of usable skills, as they are in Western countries.

  16. Johann Christoph Sturm's universal mathematics and metaphysics (German Title: Universalmathematik und Metaphysik bei Johann Christoph Sturm)

    NASA Astrophysics Data System (ADS)

    Leinsle, Ulrich G.

    In order to understand Sturm's concept of a universal mathematics as a replacement or complement of metaphysics, one first has to examine the evolution of the idea of a mathesis universalis up to Sturm, and his concept of metaphysics. According to the understanding of those times, natural theology belongs to metaphysics. The last section is concerned with Sturm's statements on the existence of God and his assessments for a physico-theology.

  17. Probleme bei der Nutzung von Offshore-Wind-energie aus Sicht des Naturschutzes

    NASA Astrophysics Data System (ADS)

    Merck, Thomas; von Nordheim, Henning

    1999-12-01

    Permissions for wind parks of together more than 1000 wind mills have been asked for regarding only the German Exclusive Economical Zone (EEZ) of the North Sea and the Baltic Sea. Following the German Ordinance for Offshore Installations permission cannot be given if flora and fauna will be affected by the installation. Wind energy plants in the offshore area are a new technique and a thorough assessment of their effects on nature is impossible at the moment. Nevertheless, likely and possible effects could be deduced from experiences on land. Thus it has to be expected that roosting, feeding or migrating sea birds will be affected due to disturbance and collision. At least on a local scale the foundations will destroy the benthos but due to their effects on the hydrology and the sedimentation pattern they may change the composition of benthic communities on a larger scale as well. Furthermore they form an artificial hard substrate that serves as habitat for epibenthic flora and fauna not typically found in great parts of the German part of the North Sea. It should be feared that artificial magnetic and electric fields generated by the cable links will affect small and large scale orientation of fishes and marine mammals. Additional disturbances could arise from noise and vibrations released into the water column as well as from the shadows generated by the turning mills. Although these wind parks at least partly will be placed far off-shore a visual disturbance of the landscape has to be expected just as on land. In addition off-shore wind parks will increase the collision risk for ships and accidents may affect areas even far away from the wind park, e.g. by oil spills. In conclusion there is sufficient reason to assume a considerable risk that off-shore wind parks will affect the environment. So far only wind parks consisting of a few mills should be placed. They have to been seen as case studies to enable the necessary research on their effects on nature.

  18. Realisierung eines verzerrungsarmen Open-Loop Klasse-D Audio-Verstärkers mit SB-ZePoC

    NASA Astrophysics Data System (ADS)

    Schnick, O.; Mathis, W.

    2007-06-01

    In den letzten Jahren hat die Entwicklung von Klasse-D Verstärkern für Audio-Anwendungen ein vermehrtes Interesse auf sich gezogen. Eine Motivation hierfür liegt in der mit dieser Technik extrem hohen erzielbaren Effizienz von über 90%. Die Signale, die Klasse-D Verstärker steuern, sind binär. Immer mehr Audio-Signale werden entweder digital gespeichert (CD, DVD, MP3) oder digital übermittelt (Internet, DRM, DAB, DVB-T, DVB-S, GMS, UMTS), weshalb eine direkte Umsetzung dieser Daten in ein binäres Steuersignal ohne vorherige konventionelle D/A-Wandlung erstrebenswert erscheint. Die klassischen Pulsweitenmodulationsverfahren führen zu Aliasing-Komponenten im Audio-Basisband. Diese Verzerrungen können nur durch eine sehr hohe Schaltfrequenz auf ein akzeptables Maß reduziert werden. Durch das von der Forschungsgruppe um Prof. Mathis vorgestellte SB-ZePoC Verfahren (Zero Position Coding with Separated Baseband) wird diese Art der Signalverzerrung durch Generierung eines separierten Basisbands verhindert. Deshalb können auch niedrige Schaltfrequenzen gewählt werden. Dadurch werden nicht nur die Schaltverluste, sondern auch Timing-Verzerrungen verringert, die durch die nichtideale Schaltendstufe verursacht werden. Diese tragen einen großen Anteil zu den gesamten Verzerrungen eines Klasse-D Verstärkers bei. Mit dem SB-ZePoC Verfahren lassen sich verzerrungsarme Open-Loop Klasse-D Audio-Verstärker realisieren, die ohne aufwändige Gegenkopplungsschleifen auskommen. Class-D amplifiers are suiteble for amplification of audio signals. One argument is their high efficiency of 90% and more. Today most of the audio signals are stored or transmitted in digital form. A digitally controlled Class-D amplifier can be directly driven with coded (modulated) data. No separate D/A conversion is needed. Classical modulation schemes like Pulse-Width-Modulation (PWM) cause aliasing. So a very high switching rate is required to minimize the aliasing component within the signal

  19. Reactivity of the "yl"-bond in uranyl(VI) complexes. 1. Rates and mechanisms for the exchange between the trans-dioxo oxygen atoms in (UO2)2(OH)2 2+ and mononuclear UO2(OH)n 2-n complexes with solvent water.

    PubMed

    Szabó, Zoltan; Grenthe, Ingmar

    2007-10-29

    The stoichiometric mechanism, rate constant, and activation parameters for the exchange of the "yl"-oxygen atoms in the dioxo uranium(VI) ion with solvent water have been studied using 17O NMR spectroscopy. The experimental rate equation, (-->)v= k(2obs)[UO2(2+)]tot2/[H+]2, is consistent with a mechanism where the first step is a rapid equilibrium 2U(17)O2(2+) + 2H2O<==>(U(17)O2)2(OH)2(2+) + 2H+, followed by the rate-determining step (U(17)O2)2(OH)2(2+) + H2O<==>(UO2)2*(OH)2(2+) + H2(17)O, where the back reaction can be neglected because the (17)O enrichment in the water is much lower than in the uranyl ion. This mechanism results in the following rate equation (-->)v= d[(UO2)2(OH)2(2+)]/dt = k(2,2)[(UO2)2(OH)2(2+)] = k(2,2*)beta(2,2)[UO2(2+)]2/[H + ]2; with k(2,2) = (1.88 +/- 0.22) x 10(4) h(-1), corresponding to a half-life of 0.13 s, and the activation parameters DeltaH++ = 119 +/- 13 kJ mol-1 and DeltaS++ = 81 +/- 44 J mol(-1) K(-1). *Beta(2,)2 is the equilibrium constant for the reaction 2UO2(2+) + 2H2O<==>(UO2)2(OH)2(2+) + 2H+. The experimental data show that there is no measurable exchange of the "yl"-oxygen in UO2(2+), UO2(OH)+, and UO2(OH)4(2-)/ UO2(OH)5(3-), indicating that "yl"-exchange only takes place in polynuclear hydroxide complexes. There is no "yl"-exchange in the ternary complex (UO2)2(mu-OH)2(F)2(oxalate)2(4-), indicating that it is also necessary to have coordinated water in the first coordination sphere of the binuclear complex, for exchange to take place. The very large increase in lability of the "yl"-bonds in (UO2)2(OH)2(2+) as compared to those of the other species is presumably a result of proton transfer from coordinated water to the "yl"-oxygen, followed by a rapid exchange of the resulting OH group with the water solvent. "Yl"-exchange through photochemical mediation is well-known for the uranyl(VI) aquo ion. We noted that there was no photochemical exchange in UO2(CO3)3(4-), whereas there was a slow exchange or photo reduction in the UO2(OH)4(2-) / UO2(OH)5(3-) system that eventually led to the appearance of a black precipitate, presumably UO2. PMID:17887747

  20. Evaluation of improved land use and canopy representation in BEIS v3.61 with biogenic VOC measurements in California

    EPA Science Inventory

    Biogenic volatile organic compounds (BVOC) participate in reactions that can lead to secondarily formed ozone and particulate matter (PM) impacting air quality and climate. BVOC emissions are important inputs to chemical transport models applied on local to global scales but cons...

  1. Evaluation of Baroreflex Effectiveness Index during Real and Simulated Microgravity: Relation to Orthostatic Intolerance

    NASA Technical Reports Server (NTRS)

    Moore, Rachel; Stenger, Michael; Platts, Steven; Lee, Stuart

    2013-01-01

    Bed Rest and Space Flight cause a significant decrease in BEI. BR causes similar changes to BEI as SF. BEI may not correlate with subjects experiencing presyncope, but error is high and n is low. Compression Garments have the potential to restore BEI after short duration BR, but do not prevent recovery.

  2. American Association of Occupational Health Nurses

    MedlinePlus

    ... OHN Career Profiles Professional Liability Publications Online Store Workplace Health & Safety Journal AAOHN.org News Archive Foundation About ... Honor/Memory of Someone Conference Information NIOSH Total Worker Health ® AAOHN Academy News AAOHN 2017 National Conference April ...

  3. Optional Elements and Variant Structures in the Productions of "Bei2" "to Give" Dative Constructions in Cantonese-Speaking Adults and Three-Year-Old Children

    ERIC Educational Resources Information Center

    Wong, Anita M.-Y.; Chow, Dorcas C.-C.; McBride-Cheng, Catherine; Stokes, Stephanie F.

    2010-01-01

    To express object transfer, Cantonese-speakers use a "ditransitive" ([V-R-T] or [V-T-R] where V = Verb, T = Theme, R = Recipient), or a more complex prepositional/serial-verb (P/SV) construction. Clausal elements in Cantonese datives can be optional (resulting in "full" versus "non-full" forms) or appear in variant orders (full non-canonical and…

  4. Limitierungen bei der Ermittlung der Grundwasserfließrichtung in tiefen Aquiferen am Beispiel des Malms im Süddeutschen Molassebecken

    NASA Astrophysics Data System (ADS)

    Savvatis, Alexandros; Steiner, Ulrich; Huber, Bernhard; Fritzer, Thomas; Schneider, Michael

    2015-12-01

    The groundwater flow direction in deep inclined aquifers is generally determined from contour maps based on the conversion of the reservoir pressure from deep wells to standardized groundwater levels. The standardizing is done with a representative water column of constant density in which an increasing depth of the aquifer has an increasing influence on the calculated groundwater levels. However, integration of new pressure data from recently drilled geothermal wells in the Malm of the South German Molasse Basin in the greater area of Munich led to a hydrogeologically unrealistic groundwater flow direction below the Alps. The present work demonstrates the applied method for standardization, performs an error analysis, and shows the limits of the applicability of this method. An alternative approach is introduced along with a concrete example where the local flow direction is determined by neighboring wells (cluster method). A sensitivity analysis with respect to the uncertainty in temperature shows that this approach provides realistic results from realistic input scenarios. The presented cluster method is therefore able to provide pilot points for calibration/verification of a basin-scale groundwater flow model.

  5. Effect of various nitrogen salts in beet pulp medium on polygalacturonase activity of Penicillium sp. 7/4B/EI 1 mutant.

    PubMed

    Szajer, I

    1978-01-01

    The highest PG activity was obtained in beet pulp with (NH4)2HPO4 in amount equivalent to 0.14--0.28% N after 7 days of growth; At optimal concentration, (NH4)2HPO4 did not influence the biomass production, but increased the pH of the culture media to above 6.0. The PG was an extracellular enzyme, acting mainly on highly esterified pectin. The attack was of a random manner, characteristic for the endo-enzymes. The enzyme was active at temperature 20 degrees C--40 degrees C and pH 5.0--6.0. PMID:81597

  6. Drei Wochen bei den Internationalen Sommerkursen in Erfurt, 22. Juli-11. August 1968 (Three Weeks at the International Summer Courses in Erfurt).

    ERIC Educational Resources Information Center

    Mayer, Elizabeth M.

    This paper discusses life in East Germany as observed by the author during a three-week program of summer courses in Erfurt. Background information includes a description of Erfurt, a brief review of its history, and analysis of the daily life of East Germans--their attitudes towards the state, physical appearance, salary structure, and…

  7. Biogenic Emissions Inventory System

    EPA Science Inventory

    ***BEIS3 is now embedded in the CMAQ model***

    The Biogenic Emissions Inventory System, Version 3 (BEIS3) is being developed to support the needs of regional and urban-scale air quality simulation models. BEIS3 is designed to be incorporated into the Sparse Matrix Op...

  8. Oxalylhydrazinium Nitrate and Dinitrate—Efficiency Meets Performance

    NASA Astrophysics Data System (ADS)

    Fischer, Dennis; Klapötke, Thomas M.; Stierstorfer, Jörg

    2014-01-01

    Oxalylhydrazinium nitrate (OHN) and dinitrate (OHDN) were synthesized by protonation of oxalyldihydrazide with nitric acid. The synthesis is extremely cost effective (∼40/kg at the lab scale) and can be carried out in large scales and very good yields. OHN and OHDN were intensively characterized by low-temperature X-ray diffraction (XRD), nuclear magnetic resonance (NMR) and vibrational spectroscopy. These new organic nitrate salts could be used as powerful ingredients in energetic formulations due to their low sensitivities (measured by Bundesanstalt für Materialforschung und Pröfung methods). Their thermal stability was investigated by differential scanning calorimetry (DSC) measurements. Further thermal studies of OHN showed compatibility with TNT (2,4,6-trinitrotoluene), DNAN (2,4-dinitroanisole), and RDX (1,3,5-trinitro-1,3,5-triazinane). The theoretical detonation and propulsion parameters of OHN and OHDN were calculated with the EXPLO5.5 code and compared to well-known insensitive explosives. The aquatic toxicity of OHN was determined by the luminescent bacteria inhibition test, yielding a much lower toxicity than RDX.

  9. Effect of liquefaction temperature on hydroxyl groups of bio-oil from loblolly pine (Pinus taeda).

    PubMed

    Celikbag, Yusuf; Via, Brian K; Adhikari, Sushil; Wu, Yonnie

    2014-10-01

    Loblolly pine was liquefied with ethylene glycol at 100, 150, 200 and 250 °C in order to analyze the effect of liquefaction temperature on hydroxyl groups of bio-oil, and to determine the source and variation of hydroxyl groups. The optimum temperature was found to be 150-200 °C. Hydroxyl number (OHN) of the bio-oil was ranged from 632 to 1430 mg KOH/g. GC-MS analysis showed that 70-90% of OHN was generated from unreacted EG. (31)P NMR analysis showed that the majority of hydroxyl groups were aliphatic, and none of the bio-oil exhibited any detectable hydroxyl groups from phenolic sources. Finally, it was found that all bio-oils were stable in terms of OHN for 2 months when stored at -10 °C. PMID:25113882

  10. ‘A Wonderfull Monster Borne in Germany’: Hairy Girls in Medieval and Early Modern German Book, Court and Performance Culture*

    PubMed Central

    Katritzky, MA

    2014-01-01

    Human hirsuteness, or pathological hair growth, can be symptomatic of various conditions, including genetic mutation or inheritance, and some cancers and hormonal disturbances. Modern investigations into hirsuteness were initiated by nineteenth-century German physicians. Most early modern European cases of hypertrichosis (genetically determined all-over body and facial hair) involve German-speaking parentage or patronage, and are documented in German print culture. Through the Wild Man tradition, modern historians routinely link early modern reception of historical hypertrichosis cases to issues of ethnicity without, however, recognising early modern awareness of links between temporary hirsuteness and the pathological nexus of starvation and anorexia. Here, four cases of hirsute females are reconsidered with reference to this medical perspective, and to texts and images uncovered by my current research at the Herzog August Library and German archives. One concerns an Italian girl taken to Prague in 1355 by the Holy Roman Empress, Anna von Schweidnitz. Another focuses on Madeleine and Antonietta Gonzalez, daughters of the ‘Wild Man’ of Tenerife, documented at German courts in the 1580s. The third and fourth cases consider the medieval bearded Sankt Kümmernis (also known as St Wilgefortis or St Uncumber), and the seventeenth-century Bavarian fairground performer Barbara Urslerin. Krankhafter menschlicher Hirsutismus kann aufgrund unterschiedlicher Ursachen auftreten, zu denen u.a. genetische Veränderungen und Vererbung, verschiedene Krebserkrankungen und hormonelle Störungen gehören. Die moderne Hirsutismus-Forschung ist im 19. Jh. von deutschen Forschern initiiert worden. Die meisten europäischen frühneuzeitlichen Erscheinungen von Hypertrichose (dem genetisch bedingten Haarwuchs am gesamten Körper und im Gesicht) gehen auf deutschsprachige Eltern oder Förderer zurück und sind in Deutschland in den Druck gelangt. Bei Untersuchungen des Motivs des

  11. [Study on carving workers of Chong xiu zheng he jing shi zheng lei bei yong ben cao (Revised Prepared Materia Medica Classified under Syndromes in Zhenghe Period) published by Huiming Xuan (Huiming Sanctum)].

    PubMed

    Liang, Fei; Li, Jian; Zhang, Wei; Zhang, Rui-Xian

    2012-11-01

    The ancient carving workers have made a great contribution to the xylographic printing art in ancient China, so the studies on them are significant for a survey of ancient Chinese printing history, and for the identification of ancient Chinese books edition. Zheng lei ben cao published by Huiming Xuan (Huiming Sanctum) in the Jin and Yuan dynasties, which is the earliest extant edition of Zhenghe version system of Zheng lei ben cao and has important literature value. Thirty carving workers were involved in its printing process. On the whole, these workers had a relatively high technique and completed a remarkably fine work. In addition to lettering, 28 persons of them also made a total of 536 pages with 900 exquisite engraving illustrations on Chinese materia medica included in this book. Because of the high levels on carving, this precious book has been the representative of Pingshui edition, which has a great reputation but has very few works now. PMID:23363847

  12. Die Rolle dialogtypischer Wortverbindungen und Wendungen bei der Vervollkommnung sprachlichen Koennens auf dem Gebiet des dialogischen Sprechens (The Role of Dialogue-Typical Word Combinations and Idioms in Perfecting Speaking Ability in the Area of Dialogue)

    ERIC Educational Resources Information Center

    Petzschler, Hermann; Zoch, Irene

    1974-01-01

    Describes exercises using typical expressions used in conversation, including idioms, partial or complete clauses, syntactic structures, etc. Refers to Herder Institute's (1971) five steps in language learning, of which Step Five includes 4000 lexical units to be mastered for active use, plus 3000 for passive recognition. Gives examples and…

  13. Quantitative Analyse von Korallengemeinschaften des Sanganeb-Atolls (mittleres Rotes Meer). II. Vergleich mit einem Riffareal bei Aqaba (nördliches Rotes Meer) am Nordrande des indopazifischen Riffgürtels

    NASA Astrophysics Data System (ADS)

    Schuhmacher, H.; Mergner, H.

    1985-12-01

    Quantitative studies of coral communities in the central and northern Red Sea were designed for comparison of the community structure in both areas. The central Red Sea provides reef-building Scleractinia and reef-inhabiting Alcyonaria with optimal temperature conditions, whereas the north tip of the Gulf of Aqaba (29°30' N) represents the northernmost outpost of coral reefs in the Indian Ocean. It is generally assumed that coral diversity decreases towards the margins of the global reef-belt. In the Red Sea, generic diversity of hermatypic Scleractinia slightly decreases from the central to the northern part (51 : 48 genera); but cnidarian species abundance (species number per 25 m2 area) was found to increase from 62 to 98 species and the Shannon-Wiener diversity index increased from 2.58 to 3.67 with regard to colony number. The mean colony size was 189 cm2 at Sanganeb-Atoll, but only 52 cm2 at Aqaba. The mean numbers of colonies were inversely related: 662 per 25 m2 at Sanganeb-Atoll and 2028 at Aqaba. Uninhabited parts of the studied areas amounted to 47 % at Sanganeb-Atoll and to 56 % at Aqaba. The community structure of the studied areas indicates that occasional perturbations prevent the progress of the community towards a low-diversity equilibrium state. Since severe hydrodynamic damage is extremely rare in 10 m depth, major disturbances may occur by sedimentation, by the interference of grazers (e. g. Diadema setosum) and due to overgrowth by space-competitors (mainly soft corals). These events are to be regarded as throwbacks in the process of monopolization of the area by well adapted species. Recovery from such perturbations (i.e. recolonization of dead areas) obviously takes place at different velocities in the northern and central Red Sea, for the mean water temperature at Aqaba is 5 °C lower than in the central Red Sea. Hence the process of taking over a given space by a few species proceeds further in the central Red Sea than at its northern end. The increase in diversity per area towards high latitudes is comparable to that with depth. It is concluded from the great number of species at Aqaba that these reefs mark the northernmost outpost of the Indian Ocean only geographically but not ecophysiologically; they would occur at even higher latitudes, if the Gulf of Aqaba extended farther north.

  14. Gottfried Kirch's (1639-1710) concept of an astronomical society - an investigation also based on his correspondence and calendars. (German Title: Der Societätsgedanke bei Gottfried Kirch (1639-1710), untersucht unter Einbeziehung seiner Korrespondenz und Kalender)

    NASA Astrophysics Data System (ADS)

    Herbst, Klaus-Dieter

    At the end of the 17th century, Gottfried Kirch was not only one of the most widely read authors of calendars, but, following the death of Hevelius in 1687, the most distinguished astronomer of the German countries. Since 1675, the idea of establishing an ``astronomical society in Germany'' emerges in his papers, and he placed himself consciously into the tradition of society foundings in the 17th century. In spite of the fact that the establishment of a purely astronomical society did not materialize, Kirch was involved in projects of other societies, e.g. in the plans of the ``Collegium Artis Consultorum'', promoted by Weigel, and finally he found himself the first astronomer of the Brandenburg society of sciences, whose establishment had been initiated by Leibniz. The evaluation of the written sources suggests that his religious attitude that converged on pietism, inspired him to establish a scientific society. The reasons for the failure of his attempt are manifold. It is important to point out that Kirch was, on one hand, very much dependent on earning his living by his calendar work, since he had no support for his astronomical profession from a potentate. On the other hand, he could publish his (and others') astronomical observations in the scientific journal ``Acta Eruditorum'', which had appeared in Leipzig since 1682, thus fulfilling an essential task of such an astronomical society.

  15. The effect of hydroxylation on CNT to form Chitosan-CNT composites: A DFT study

    NASA Astrophysics Data System (ADS)

    Yu, Rui; Ran, Maofei; Wen, Jie; Sun, Wenjing; Chu, Wei; Jiang, Chengfa; He, Zhiwei

    2015-12-01

    The effect of types of CNTs (pristine and hydroxylated) on the synthesis of Chitosan-CNT (CS-CNT) composites was investigated theoretically. The adsorption energy (Eads) of CS on the pristine CNT and hydroxylated CNTs (CNT-OHn, n = 1-6) as well as the structural and electronic properties of said composites have been investigated. Results show that the adsorption of CS on CNT and CNT-OHn is thermodynamically favored. The Eads of CS on CNTs was calculated to be -20.387 kcal/mol from electrostatic interactions. For CS adsorbed into CNT-OHn, Eads ranges from -20.612 to -37.567 kcal/mol. Hydroxyl groups on CNT are the main adsorption sites for CS loading onto CNT-OHn via hydrogen-bond interactions. The CS-CNT-OH3 is the most sable composite among tested complexes. The energy gap (ΔEgap) of CS-CNT-OH3 was calculated less than pristine CNT and CNT-OH3, indicative of the composites being more reactive than that of pristine CNTs and CNT-OH3. It was proved that CS can transfer electron to the hydroxylated CNTs, thus overcoming the drawbacks of CNTs being chemically inert.

  16. Nationale Roadmap Embedded Systems

    NASA Astrophysics Data System (ADS)

    Damm, Werner; Achatz, Reinhold; Beetz, Klaus; Broy, Manfred; Daembkes, Heinrich; Grimm, Klaus; Liggesmeyer, Peter

    Eingebettete Systeme" sind in ihrem Softwareanteil nicht sichtbar und doch hoch relevant für den Wirtschaftsstandort Deutschland. Ihre Bedeutung fasst die vorliegende Nationale Roadmap Embedded Systems in den folgenden 10 Thesen zusammen: These 1 Die zentralen ökonomischen und gesellschaftlichen Herausforderungen in Deutschland lassen sich ohne die Querschnittstechnologie Embedded Systems nicht lösen1.

  17. Blind Childrens Center Annual Report, 2008-2009

    ERIC Educational Resources Information Center

    Blind Childrens Center, 2009

    2009-01-01

    When entering the Blind Childrens Center (BCC), what a person might not realize is that four of the five visually impaired children in a classroom share the same diagnosis of Optic Nerve Hypoplasia (OHN). ONH is the leading cause of blindness and visual impairment in young children. It is important that these children participate in an inclusive…

  18. The effect of SST emissions on the earth's ozone layer

    NASA Technical Reports Server (NTRS)

    Whitten, R. C.; Turco, R. P.

    1974-01-01

    The work presented here is directed toward assessment of environmental effects of the supersonic transport (SST). The model used for the purpose includes vertical eddy transport and the photochemistry of the O-H-N system. It is found that the flight altitude has a pronounced effect on ozone depletion. The largest ozone reduction occurs for NO deposition above an altitude of 20 km.

  19. Is mammary reconstruction with the anatomical Becker expander a simple procedure? Complications and hidden problems leading to secondary surgical procedures: a follow-up study.

    PubMed

    Farace, Francesco; Faenza, Mario; Bulla, Antonio; Rubino, Corrado; Campus, Gian Vittorio

    2013-06-01

    Debate over the role of Becker expander implants (BEIs) in breast reconstruction is still ongoing. There are no clear indications for BEI use. The main indications for BEI use are one-stage breast reconstruction procedure and congenital breast deformities correction, due to the postoperative ability to vary BEI volume. Recent studies showed that BEIs were removed 5 years after mammary reconstruction in 68% of operated patients. This entails a further surgical procedure. BEIs should not, therefore, be regarded as one-stage prostheses. We performed a case-series study of breast reconstructions with anatomically shaped Becker-35™ implants, in order to highlight complications and to flag unseen problems, which might entail a second surgical procedure. A total of 229 patients, reconstructed from 2005 to 2010, were enrolled in this study. Data relating to implant type, volume, mean operative time and complications were recorded. All the patients underwent the same surgical procedure. The minimum follow-up period was 18 months. During a 5-year follow-up, 99 patients required secondary surgery to correct their complications or sequelae; 46 of them underwent BEI removal within 2 years of implantation, 56 within 3 years, 65 within 4 years and 74 within 5 years. Our findings show that two different sorts of complications can arise with these devices, leading to premature implant removal, one common to any breast implant and one peculiar to BEIs. The Becker implant is a permanent expander. Surgeons must, therefore, be aware that, once positioned, the Becker expander cannot be adjusted at a later date, as in two-stage expander/prosthesis reconstructions for instance. Surgeons must have a clear understanding of possible BEI complications in order to be able to discuss these with their patients. Therefore, only surgeons experienced in breast reconstruction should use BEIs. PMID:23478009

  20. (E)-2-[(2-Bromophenylimino)methyl]-5-methoxyphenol: X-ray and DFT-calculated structures

    SciTech Connect

    Kosar, B. Albayrak, C.; Odabasoglu, M.; Bueyuekguengoer, O.

    2010-12-15

    The crystal structure of (E)-2-[(2-Bromophenylimino)methyl]-5-methoxyphenol is determined by using X-ray diffraction and then the molecular structure is investigated with density functional theory (DFT). X-Ray study shows that the title compound has a strong intramolecular O-H-N hydrogen bond and three dimensional crystal structure is primarily determined by C-H-{pi} and weak van der Waals interactions. The strong O-H-N bond is an evidence of the preference for the phenol-imine tautomeric form in the solid state. Optimized molecular geometry is calculated with DFT at the B3LYP/6-31G(d,p) level. The IR spectra of compound were recorded experimentally and calculated to compare with each other. The results from both experiment and theoretical calculations are compared in this study.

  1. Quantification of 21 metabolites of methylnaphthalenes and polycyclic aromatic hydrocarbons in human urine.

    PubMed

    Li, Zheng; Romanoff, Lovisa C; Trinidad, Debra A; Pittman, Erin N; Hilton, Donald; Hubbard, Kendra; Carmichael, Hasan; Parker, Jonathan; Calafat, Antonia M; Sjödin, Andreas

    2014-05-01

    Polycyclic aromatic hydrocarbons (PAHs) and their alkylated derivatives, such as methylnaphthalenes (MeNs), are harmful pollutants ubiquitously present in the environment. Exposure to PAHs has been linked to a variety of adverse health effects and outcomes, including cancer. Alkyl PAHs have been proposed as petrogenic source indicators because of their relatively high abundance in unburned petroleum products. We report a method to quantify 11 urinary methylnaphthols (Me-OHNs), metabolites of 1- and 2-methylnaphthalenes, and 10 monohydroxy PAH metabolites (OH-PAHs), using automated liquid-liquid extraction and isotope dilution gas chromatography tandem mass spectrometry (GC-MS/MS). After spiking urine (1 mL) with (13)C-labeled internal standards, the conjugated target analytes were hydrolyzed enzymatically in the presence of ascorbic acid. Then, their free species were preconcentrated into 20 % toluene in pentane, derivatized and quantified by GC-MS/MS. The 11 Me-OHNs eluted as 6 distinct chromatographic peaks, each representing 1 - 3 isomers. Method detection limits were 1.0- 41 pg/mL and the coefficients of variation in quality control materials were 4.7 - 19 %. The method was used to analyze two National Institute of Standards and Technology's Standard Reference Materials® and samples from 30 smokers and 30 non-smokers. Geometric mean concentrations were on average 37 (Me-OHNs) and 9.0 (OH-PAHs) fold higher in smokers than in non-smokers. These findings support the usefulness of Me-OHNs as potential biomarkers of non-occupational exposure to MeNs and sources containing MeNs. PMID:24714969

  2. Quantification of Twenty-one Metabolites of Methylnaphthalenes and Polycyclic Aromatic Hydrocarbons in Human Urine

    PubMed Central

    Li, Zheng; Romanoff, Lovisa C.; Trinidad, Debra A.; Pittman, Erin N.; Hilton, Donald; Hubbard, Kendra; Carmichael, Hasan; Parker, Jonathan; Calafat, Antonia M.; Sjödin, Andreas

    2015-01-01

    Polycyclic aromatic hydrocarbons (PAHs) and their alkylated derivatives, such as methylnaphthalenes (MeNs), are harmful pollutants ubiquitously present in the environment. Exposure to PAHs has been linked to a variety of adverse health effects and outcomes, including cancer. Alkyl PAHs have been proposed as petrogenic source indicators because of their relatively high abundance in unburned petroleum products. We report a method to quantify 11 urinary methyl naphthols (Me-OHNs), metabolites of 1- and 2-methylnaphthalenes, and 10 monohydroxy PAH metabolites (OH-PAHs), using automated liquid-liquid extraction and isotope dilution gas chromatography tandem mass spectrometry (GC-MS/MS). After spiking urine (1 mL) with 13C-labeled internal standards, the conjugated target analytes were hydrolyzed enzymatically in the presence of ascorbic acid. Then, their free species were preconcentrated into 20% toluene in pentane, derivatized and quantified by GC-MS/MS. The 11 Me-OHNs eluted as 6 distinct chromatographic peaks, each representing 1–3 isomers. Method detection limits were 1.0–41 pg/mL and the coefficients of variance in quality control materials were 4.7–19%. The method was used to analyze two National Institute of Standards and Technology’s Standard Reference Materials and samples from 30 smokers and 30 non-smokers. Geometric mean concentrations were on average 37 (Me-OHNs) and 9.0 (OH-PAHs) fold higher in smokers than in non-smokers. These findings support the usefulness of Me-OHNs as potential biomarkers of non-occupational exposure to MeNs and sources containing MeNs. PMID:24714969

  3. 2-Aminopyrimidine-3,3,3-triphenylpropanoic acid (1/1).

    PubMed

    Serafin, Mateusz F; Wheeler, Kraig A

    2007-11-01

    The title bimolecular compound, C(4)H(5)N(3).C(21)H(18)O(2), constructed from 2-aminopyrimidine and 3,3,3-triphenylpropanoic acid, forms a tetramolecular hydrogen-bonded motif via O-H...N, N-H...O and N-H...N contacts. This aggregate organizes to give crystal-packing motifs with hydrophilic and hydrophobic regions. PMID:17989479

  4. Adsorption of Cu(II) on Oxidized Multi-Walled Carbon Nanotubes in the Presence of Hydroxylated and Carboxylated Fullerenes

    PubMed Central

    Wang, Jing; Li, Zhan; Li, Shicheng; Qi, Wei; Liu, Peng; Liu, Fuqiang; Ye, Yuanlv; Wu, Liansheng; Wang, Lei; Wu, Wangsuo

    2013-01-01

    The adsorption of Cu(II) on oxidized multi-walled carbon nanotubes (oMWCNTs) as a function of contact time, pH, ionic strength, temperature, and hydroxylated fullerene (C60(OH)n) and carboxylated fullerene (C60(C(COOH)2)n) were studied under ambient conditions using batch techniques. The results showed that the adsorption of Cu(II) had rapidly reached equilibrium and the kinetic process was well described by a pseudo-second-order rate model. Cu(II) adsorption on oMWCNTs was dependent on pH but independent of ionic strength. Compared with the Freundlich model, the Langmuir model was more suitable for analyzing the adsorption isotherms. The thermodynamic parameters calculated from temperature-dependent adsorption isotherms suggested that Cu(II) adsorption on oMWCNTs was spontaneous and endothermic. The effect of C60(OH)n on Cu(II) adsorption of oMWCNTs was not significant at low C60(OH)n concentration, whereas a negative effect was observed at higher concentration. The adsorption of Cu(II) on oMWCNTs was enhanced with increasing pH values at pH < 5, but decreased at pH ≥ 5. The presence of C60(C(COOH)2)n inhibited the adsorption of Cu(II) onto oMWCNTs at pH 4–6. The double sorption site model was applied to simulate the adsorption isotherms of Cu(II) in the presence of C60(OH)n and fitted the experimental data well. PMID:24009683

  5. Thermal-hydraulic interfacing code modules for CANDU reactors

    SciTech Connect

    Liu, W.S.; Gold, M.; Sills, H.

    1997-07-01

    The approach for CANDU reactor safety analysis in Ontario Hydro Nuclear (OHN) and Atomic Energy of Canada Limited (AECL) is presented. Reflecting the unique characteristics of CANDU reactors, the procedure of coupling the thermal-hydraulics, reactor physics and fuel channel/element codes in the safety analysis is described. The experience generated in the Canadian nuclear industry may be useful to other types of reactors in the areas of reactor safety analysis.

  6. Photoinduced ionization and dissociation of aniline-(methanol)n clusters

    NASA Astrophysics Data System (ADS)

    Park, Hye Sun; Nam, Sang Hwan; Song, Jae Kyu; Park, Seung Min

    2007-04-01

    A linear tandem-type time-of-flight mass spectrometer was employed to study unimolecular dissociation of metastable aniline+-(methanol)n (An+-(CH3OH)n, n = 2-9) cluster cations formed by two-photon ionization of neutral clusters. The dominant dissociation channel was to liberate a single methanol molecule, namely, An+-(CH3OH)n --> An+-(CH3OH)n-1 + CH3OH. The decay time constant of the ions ranged from 65 to 460 [mu]s and turned out to be highly dependent on the cluster size. Also, hydrogen transfer mechanism in the formation of An+-(CH3OH)nH was examined by analyzing experimental results from isotopomers, such as deuterated An-d7+-(CH3OD) and An-d7+-(CD3OD) cluster ions. Density functional theory calculations were carried out to obtain optimized structures for neutral and ionic clusters and to support mechanisms related to the hydrogen transfer and unimolecular dissociation reaction.

  7. Chirurgie angeborener Herzfehler

    NASA Astrophysics Data System (ADS)

    Schreiber, Christian; Libera, Paul; Lange, Rüdiger

    Störungen der embryonalen Entwicklung in der frühen Phase der Schwangerschaft können zu Fehlbildungen am Herz- und Gefäßsystem führen. Die Häufigkeit liegt bei 0.8-1 % aller lebend geborenen Kinder. In Deutschland werden jedes Jahr etwa 6.000 Kinder mit einem Herzfehler geboren (Quelle: http://www.kompetenznetzahf.de). Das Spektrum reicht von einfachen Fehlern, die das Herz-Kreislauf-System wenig beeinträchtigen, bis zu sehr schweren Herzerkrankungen, die unbehandelt zum Tode führen. Fortschritte der Kinderkardiologie, Herzchirurgie und Anästhesie ermöglichen heute ein Überleben bei über 90 % der Patienten. Auch die spezialisierte Pränataldiagnostik (vorgeburtliche Diagnostik) ermöglicht schon die frühe Weichenstellung für mögliche Therapieoptionen. Bei der chirurgischen Therapie ist jedoch festzuhalten, dass ein Herzfehler entweder korrigierend behandelt wird oder nur "palliiert“ werden kann. Bei letzterer Therapie wird bei einem Patienten eine medizinische Maßnahme durchgeführt, die nicht die Herstellung normaler Körperfunktionen zum Ziel hat, sondern in Anpassung an die physiologischen Besonderheiten des Patienten dessen Zustand lediglich stabilisiert und optimiert. Dies kann beispielsweise bei einer nicht korrigierbaren angeborenen Fehlbildung notwendig sein, bei der lediglich eine funktionelle Herzkammer vorhanden ist (z. B. hypoplastisches Linksherz). Hierbei muss eine prothetische Verbindung zur Lungenstrombahn in der Folgezeit entfernt werden.

  8. Precise orbit determination of Beidou Satellites at GFZ

    NASA Astrophysics Data System (ADS)

    Deng, Zhiguo; Ge, Maorong; Uhlemann, Maik; Zhao, Qile

    2014-05-01

    In December 2012 the Signal-In-Space Interface Control Document (ICD) of the BeiDou Navigation Satellite System (BeiDou system) was published. Currently the initial BeiDou regional navigation satellite system consisting of 14 satellites was completed, and provides observation data of five Geostationary-Earth-Orbit (GEO)satellites, five Inclined-GeoSynchronous-Orbit (IGSO) satellites and four Medium-Earth-Orbit (MEO) satellites. The Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences (GFZ) contributes as one of the analysis centers to the International GNSS Service (IGS) since many years. In 2012 the IGS began the "Multi GNSS EXperiment" (MGEX), which supports the new GNSS, such as Galileo, Compass, and QZSS. Based on tracking data of BeiDou-capable receivers from the MGEX and chinese BeiDou networks up to 45 global distributed stations are selected to estimate orbit and clock parameters of the GPS/BeiDou satellites. Some selected results from the combined GPS/BeiDou data processing with 10 weeks of data from 2013 are shown. The quality of the orbit and clock products are assessed by means of orbit overlap statistics, clock stabilities as well as an independent validation with SLR measurements. At the end an outlook about GFZ AC's future Multi-GNSS activities will be given.

  9. Multicentric Benign Epithelial Inclusions in a Free-ranging Risso's Dolphin (Grampus griseus).

    PubMed

    Diaz-Delgado, J; Quesada-Canales, O; Arbelo, M; Sierra, E; Edwards, J F; Suarez-Bonnet, A; Santana-Suarez, C; Espinosa de Los Monteros, A; Fernandez, A

    2016-01-01

    This report describes the histological and immunohistochemical features of multicentric, benign, epithelial inclusions (BEIs) in a free-ranging, adult, female Risso's dolphin (Grampus griseus). The differential diagnoses included ectopic hamartomatous epithelial inclusions, non-Müllerian choristoma, Müllerian choristoma and low-grade metastatic carcinoma/mesothelioma. The most likely diagnosis of such BEIs was multicentric, embolic, reactive mesothelium, as suggested by cytomorphological and immunophenotypical features of the BEIs, the occurrence of focal pleural rupture and the immunophenotype of the pleural mesothelium. The former represents a pathological condition not previously reported in a marine mammal species, rarely described in animals, and relatively infrequently recognized in man. PMID:27392421

  10. Crystal engineering using bisphenols and trisphenols. Complexes with 1,10-phenanthroline: hydrogen-bonded chains in adducts with 4,4'-biphenol (1/1) and 4,4'-sulfonyldiphenol (2/3), pi-pi stacked chains in the (1/2) adduct with 4,4'-thiodiphenol, and pairwise-interwoven nets in 1,1,1-tris(4-hydroxyphenyl)ethane-1,10-phenanthroline-methanol (1/1/1).

    PubMed

    Ferguson; Glidewell; Lavender

    1999-08-01

    In 4,4'-biphenol-1,10-phenanthroline (1/1) [systematic name: 4,4'-biphenyldiol-1,10-phenanthroline (1/1)] the diphenol molecules lie across centres of inversion and the phenanthroline molecules lie across twofold rotation axes; the phenanthroline molecules act as chain-building units and the molecular components are linked into steeply zigzag C(16) chains parallel to [101] by means of O-H.N hydrogen bonds. In the structure of 4,4'-thiodiphenol-1,10-phenanthroline (1/2) the phenanthroline molecules act as chain-terminating units; the supramolecular aggregation is finite, with the bisphenol linked to each phenanthroline molecule by means of a single O-H.N hydrogen bond. pi-pi stacking interactions between the phenanthroline molecules in neighbouring hydrogen-bonded aggregates serve to link these aggregates into a continuous two-dimensional array. The phenanthroline molecules in 4,4'-sulfonyldiphenol-1,10-phenanthroline (2/3) play two roles: molecules in general positions act as chain-terminating units and are linked to the sulfonyldiphenol molecules by means of three-centre O-H.(N)(2) hydrogen bonds, while those lying across twofold rotation axes act as chain builders and are linked to two different sulfonyldiphenol molecules by means of a two-centre O-H.N hydrogen bond in each case; the resulting U-shaped five-component aggregates are further linked by C-H.O=S hydrogen bonds into a C(3)(3)(17)[R(2)(2)(12)] 'chain of rings' along [001]. In 1,1,1-tris(4-hydroxyphenyl)ethane-1,10-phenanthroline-methanol (1/1/1) [systematic name: 4,4',4"-ethylidynetriphenol-1,10-phenanthroline-methanol (1/1/1)] the phenanthroline molecules again act as chain-terminating units: the trisphenol molecules and the methanol molecules are linked by O-H.O hydrogen bonds into two-dimensional nets built from R(6)(6)(42) rings, and pairs of these nets are interwoven. The formation of each net utilizes two hydroxyl groups per trisphenol molecule as hydrogen-bond donors and the remaining hydroxyl

  11. Sustainability Indicators and Metrics

    EPA Science Inventory

    Sustainability is about preserving human existence. Indicators and metrics are absolutely necessary to provide at least a semi-quantitative assessment of progress towards or away from sustainability. Otherwise, it becomes impossible to objectively assess whether progress is bei...

  12. Mikrokristallbildung und intermolekulare Triplett-Triplett-Energieiibertragung in festen transparenten Glasern bei 77 K. Das System N-Methylcarbazol/Naphthalin / Microcrystal Formation and Intermolecular Triplet-Triplet Energy Transfer in Rigid Transparent Glasses at 77 K. The System N-Methyl-earbazole / Naphthalene

    NASA Astrophysics Data System (ADS)

    Zander, M.

    1984-05-01

    The efficient intermolecular triplet-triplet energy transfer between N-methylcarbazole (donor) and naphthalene (acceptor) observed at 10-2 ᴍ concentration of donor and acceptor in a rigid transparent methylcyclohexane/n-pentane glass at 77 K is shown to occur in microcrystals of the donor containing small amounts of the acceptor

  13. Combined therapy of septicemia with ofloxacin and/or synthetic trehalose dicorynomycolate (S-TDCM) in irradiated and wounded mice (kombinierte therapie der septikaemie mit ofloxacin und/oder synthetischem trehalose-dicorynomycolat (s-tdcm) bei bestrahlten und verwundeten maeusen)

    SciTech Connect

    Madonna, G.S.; Moore, M.M.; Ledney, G.D.; Elliot, T.B.; Brook, I.

    1989-01-01

    Following lethal irradiation, mice usually succumb to sepsis as a result of translocation of intestinal bacteria and impairment of the host defense system. Additional trauma in these immunocompromised mice further increases susceptibility to bacterial infection from either endogenous or exogenous origin. Treatment with ofloxacin or synthetic trehalose dicorynemycolate (S-TDCM) was evaluated in mice, which were lethally irradiated and wounded, and which died with sepsis within six days. Wounding was performed on C3H/HeN mice anesthetized by inhalation of methoxyfurane. Dorsal skin and muscle equal to 30% total body surface was removed 1 h after 8.0 Gy gamma radiation. S-TDCM, which augments nonspecific resistance to infection in irradiated mice, was given once i.p. immediately after wounding. Oxfloxacin was injected s.c. daily from day 0 to day 10. Staphylococcus aureus, Streptococcus faecium, and Escherichia coli were isolated from both the livers and wound sites of moribund, untreated mice 4 and 5 days postirradiation.

  14. On the size of the ptolemaic system of the world - a study based on two figures by Johannes Kepler. (German Title: Über die Gröszlig;e des ptolemäischen Weltsystems - Eine Studie, veranlasst durch zwei Bilder bei Johannes Kepler)

    NASA Astrophysics Data System (ADS)

    Oberschelp, Arnold

    It is well known that the geocentric system according to Ptolemy is almost twice as large as the heliocentric planetary system of Copernicus. There are, however, two pictures, given by Kepler in his «Mysterium Cosmographicum» of 1596 which - at first glance - seem to contradict this. The first picture of the heliocentric system is drawn to scale. The second picture shows a geocentric system, which seems to be too small. The puzzle about the size is solved rather trivially by the fact - which is not mentioned by Kepler and which may be overlooked - that the geocentric picture is not drawn to scale and that the angles do not correspond to the degrees noted at them. In order to get a geocentric picture drawn to scale - taking Kepler's degrees for granted - it is necessary to discuss some details of the ptolemaic system. The result is, however, a geocentric system which is too big. The solution of this new puzzle is not obvious. It turns out that one of Keplers degrees (for Mars) does not correspond to the parameters of Ptolemy. Actually, in his book of 1596, Kepler's topic is not the ptolemaic system nor the copernican distances, but his heliocentric model with the five regular polyhedra. While it is interesting to note all these facts, Kepler's pictures and degrees, for the size of the ptolemaic system, lead to a dead end. Using the parameters from the «Almagest» and the principle of nested spheres from the «Planetary Hypotheses» a distance scale (Tab. 10) for the geocentric system is derived. This distance scale, however, is somewhat different from the well known ptolemaic distance scale (Tab. 1). This puzzle is not resolved, but due to the fact that different sources («Almagest» and «Planetary Hypotheses») of Ptolemy are involved. The distances of Tab. 10 correspond better to the ptolemaic system, since the relative thickness of the spheres is computed from the rather precise parameters (eccentricities and epicycle radii) of the «Almagest». The distances of Tab. I, given in the «Planetary Hypotheses», use values for the relative thicknesses of the spheres which are rounded off. Since the pictures of Kepler, when viewed together, are misleading, two new pictures of the copernican and ptolemaic planetary systems are given drawn to the same scale. A final remark is about the radius of the «tychonic system».

  15. Die Lösungsmittelabhängigkeit der Elektronenspektren und die Änderung der Dipoleigenschaften N-substituierter Acridone bei elektronischer Anregung / The Solvent Dependence of the Electronic Spectra and the Change of the Dipole Properties of N-Substituted Acridones at Electronic Excitation

    NASA Astrophysics Data System (ADS)

    Siegmund, M.; Bendig, J.

    1980-10-01

    The absorption and fluorescence spectra of acridone, N-methylacridone and N-phenylacridone are measured at 298 K for 35 solvents of different polarity. For the long wave 1La-transition, which shows a distinct positive solvatochromism, the oscillator strenght and the natural fluorescence lifetime are calculated. The change of the dipole moment (pd), determined from the Stokes' shift as a function of solvent polarity, is nearly parallel to that of the ground state (pg). The absolute values and directions of pg and pe confirm the increasing polar character of the S1-state within the sequence N-phenylacridone, acridone and N-methylacridone. These values are used for an interpretation of the charge distribution and solvatation of the S0- and S1-states. By consideration of the solvent relaxation and the activation energy of the temperature dependent S1-T2 intersystem crossing process it is shown that in addition to the decrease of the S1-energy with increasing solvent polarity the T2-energy increases relative to S0, especially in the case of protic solvents.

  16. An open, self-controlled study on the efficacy of topical indoxacarb for eliminating fleas and clinical signs of flea-allergy dermatitis in client-owned dogs in Queensland, Australia

    PubMed Central

    Fisara, Petr; Sargent, Roger M; Shipstone, Michael; von Berky, Andrew; von Berky, Janet

    2014-01-01

    basierend auf klinischer Symptomatik, positiven Intradermaltests und positiver Serologie auf Flohallergen diagnostiziert worden waren. Methoden Eine offene, nicht kontrollierte Studie, in der alle Hunde mit topischem Indoxacarb in 4 wöchigen Intervallen, drei Mal über einen Zeitraum von 12 Wochen behandelt wurden. Ergebnisse Vierundzwanzig Hunde beendeten die Studie. Eine gänzliche Abheilung der klinischen Anzeichen von FAD wurde in 21 Fällen beobachtet (87,5%), bei nahezu völligem Verschwinden oder einer deutlichen Verbesserung in den restlichen drei Fällen. Die durchschnittlichen klinischen Werte (Canine Atopic Dermatitis Extent and Severity Index-03) waren in der zwölften Woche um 93,3% reduziert. Die durchschnittlichen, von den BesitzerInnen beurteilten, Juckreizwerte waren in der zwölften Woche um 88% reduziert. Die durchschnittliche Anzahl an Flöhen war in den Wochen 8 und 12 um 97,7 bzw 100% reduziert. Schlussfolgerungen und klinische Bedeutung Indoxacarb, welches topisch alle 4 Wochen 12 Wochen lang ohne begleitende juckreizstillende Behandlung oder einer Behandlung von Ektoparasiten verabreicht wurde, milderte die Flohinfestationen bei allen Hunden und die mit FAD auftretenden klinischen Symptome in einer großen Proportion dieser Hundepopulation, die in einer schwierigen Umgebung mit hohem Flohvorkommen, lebten. PMID:24797425

  17. Biogenic emission measurement and inventories determination of biogenic emissions in the eastern United States and Texas and comparison with biogenic emission inventories

    NASA Astrophysics Data System (ADS)

    Warneke, C.; de Gouw, J. A.; Del Negro, L.; Brioude, J.; McKeen, S.; Stark, H.; Kuster, W. C.; Goldan, P. D.; Trainer, M.; Fehsenfeld, F. C.; Wiedinmyer, C.; Guenther, A. B.; Hansel, A.; Wisthaler, A.; Atlas, E.; Holloway, J. S.; Ryerson, T. B.; Peischl, J.; Huey, L. G.; Hanks, A. T. Case

    2010-04-01

    During the NOAA Southern Oxidant Study 1999 (SOS1999), Texas Air Quality Study 2000 (TexAQS2000), International Consortium for Atmospheric Research on Transport and Transformation (ICARTT2004), and Texas Air Quality Study 2006 (TexAQS2006) campaigns, airborne measurements of isoprene and monoterpenes were made in the eastern United States and in Texas, and the results are used to evaluate the biogenic emission inventories BEIS3.12, BEIS3.13, MEGAN2, and WM2001. Two methods are used for the evaluation. First, the emissions are directly estimated from the ambient isoprene and monoterpene measurements assuming a well-mixed boundary layer and are compared with the emissions from the inventories extracted along the flight tracks. Second, BEIS3.12 is incorporated into the detailed transport model FLEXPART, which allows the isoprene and monoterpene mixing ratios to be calculated and compared to the measurements. The overall agreement for all inventories is within a factor of 2 and the two methods give consistent results. MEGAN2 is in most cases higher, and BEIS3.12 and BEIS3.13 lower than the emissions determined from the measurements. Regions with clear discrepancies are identified. For example, an isoprene hot spot to the northwest of Houston, Texas, was expected from BEIS3 but not observed in the measurements. Interannual differences in emissions of about a factor of 2 were observed in Texas between 2000 and 2006.

  18. Hydrogen bonding and pi-pi interactions in a laminar structure: benzene-1,3-dicarboxylic acid-4-methylpyridine (1/2).

    PubMed

    Jin, Zhi-Min; Feng, Hai; Tu, Bing; Li, Mei-Chao; Hu, Mao-Lin

    2005-10-01

    The title complex, C8H6O4.2C6H7N, consists of two crystallographically independent 1:2 clusters of benzene-1,3-dicarboxylic acid and 4-methylpyridine. Each cluster, the components of which are linked by O-H...N hydrogen bonds, is almost planar by alignment of C-H...O hydrogen bonds. Herring-bone ribbons of clusters are formed by other C-H...O hydrogen bonds, and these ribbons are further packed to form a laminar structure by pi-pi interactions. PMID:16210766

  19. Reversible proton transfer phenomenon in the 2,4-dichlorophenol-triethylamine hydrogen-bonded complex studied by low-temperature 1H NMR spectroscopy

    NASA Astrophysics Data System (ADS)

    Ilczyszyn, Marek; Ratajczak, Henryk; Ladd, John A.

    1988-12-01

    Low-temperature 1H NMR studies of the bridging OHN signal in the hydrogen-bonded complex formed between 2,4-dichlorophenol and triethylamine in C 2H 5Cl solution have demonstrated for the first time that separate signals for the molecular and ion-pair forms of this type of system can be observed. The temperature dependence of these signals leads to thermodynamic and kinetic quantities which suggest that the potential energy profile of the hydrogen bond is roughly symmetric with a double minimum.

  20. Kanban - der Weg ist das Ziel

    NASA Astrophysics Data System (ADS)

    Aull, Florian; Berlak, Joachim; Dickmann, Eva; Dickmann, Philipp; Fischäder, Holm; Gerlach, Joachim; Henneberg, Jens; Kapalla, Klaus; Kress, Oliver; Kuttler, Robert; Schneider, Herfried M.; Schürle, Philipp; Stellpflug, Franz-Josef; Wannenwetsch, Ralph; Wulz, Johannes; Zäh, Michael F.

    Wenn man aktuell Produktionsbereiche in Deutschland und Europa besucht, fallen im Zusammenhang mit modernen Produktionsmethoden immer öfter die Begriffe Kanban (jap. Karte, Signal) und Pull-Produktion, und dies nicht ohne Stolz, da diese mit dem schillernden Vorbild des Toyota Produktionssystems in Zusammenhang stehen. Tatsächlich ist Kanban ein integraler Bestandteil moderner Produktionssysteme. Blickt man aber im Rahmen von Prozessanalysen hinter die Fassaden", d. h. in die tägliche Praxis der Arbeitsprozesse, wird man schnell desillusioniert - die viel gepriesenen klassischen Kanban-Regeln werden im Tagesgeschäft nicht eingehalten.

  1. Das Märchen vom Zauberer im weißen Kittel: Mythen um berühmte Experimente und Experimentatoren

    NASA Astrophysics Data System (ADS)

    Hentschel, Klaus

    2003-09-01

    Um berühmte Experimentatoren und Experimente ranken sich ebenso Mythen wie um geniale Theoretiker. Sie sind in populärwissenschaftlichen Büchern, Lehrbüchern und sogar in wissenschaftshistorischen Texten verbreitet. Die durch die Aufklärung etablierte Kultur des eleganten Schauexperiments vermittelt ein schiefes Bild vom mühsamen Weg vieler Experimentatoren zum dargestellten Ergebnis. Auch der Mythos des einsamen, genialen Experimentators ohne Helfer widerspricht dem historischen Befund. Gleiches gilt für das experimentum crucis, das eine Theorie als entscheidendes Experiment belegen soll. Die historische Forschung zeigt, dass es eine lange, eigenständige Tradition der experimentellen und instrumentellen Arbeit gibt.

  2. Preliminary Analyses of Beidou Signal-In Anomaly Since 2013

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Ren, J.; Liu, W.

    2016-06-01

    As BeiDou navigation system has been operational since December 2012. There is an increasing desire to use multiple constellation to improve positioning performance. The signal-in-space (SIS) anomaly caused by the ground control and the space vehicle is one of the major threats to affect the integrity. For a young Global Navigation Satellite System, knowledge about SIS anomalies in history is very important for not only assessing the SIS integrity performance of a constellation but also providing the assumption for ARAIM (Advanced Receiver Autonomous Integrity Monitoring). In this paper, the broadcast ephemerides and the precise ones are pre-processed for avoiding the false anomaly identification. The SIS errors over the period of Mar. 2013-Feb. 2016 are computed by comparing the broadcast ephemerides with the precise ones. The time offsets between GPST (GPS time) and BDT (BeiDou time) are estimated and removed by an improved estimation algorithm. SIS worst-UREs are computed and a RMS criteria are investigated to identify the SIS anomalies. The results show that the probability of BeiDou SIS anomalies is in 10-3 level in last three years. Even though BeiDou SIS integrity performance currently cannot match the GPS integrity performances, the result indicates that BeiDou has a tendency to improve its integrity performance.

  3. Renaturierung von Ökosystemen in urban-industriellen Landschaften

    NASA Astrophysics Data System (ADS)

    Rebele, Franz

    Die Urbanisierung ist ein weltweit stattfindender Prozess mit weitreichenden Auswirkungen auf Mensch und Natur. In Mitteleuropa leben heute etwa 80% aller Bewohner in Städten. Urban-industrielle Landschaften gehören deshalb zur unmittelbaren Lebensumwelt der meisten Menschen. Allein in Deutschland wird heute täglich eine Fläche von 120 ha neu für Siedlungs- und Verkehrszwecke in Anspruch genommen. Zu den Siedlungs- und Verkehrsflächen zählen Gebäude-und gebäudebezogene Freiflächen, Verkehrsflächen, Erholungsflächen und Friedhöfe sowie Betriebsflächen für Industrie und Gewerbe. Nicht enthalten sind Tagebauflächen zum Abbau von Bodenschätzen (Kapitel 13). In Deutschland liegt der Anteil der Siedlungs- und Verkehrsflächen an der Gesamtfläche derzeit bei ca. 13%, in Österreich bei 5 % und in der Schweiz bei knapp 7 %. Charakteristisch für die heutige Entwicklung in Mitteleuropa ist, dass die Prozesse der Urbanisierung und der Flächeninanspruchnahme für Siedlung und Verkehr nicht ursächlich mit einem Bevölkerungswachstum verbunden sind, d. h. dass Freiflächen auch bei stagnierender oder in manchen Regionen sogar bei sinkender Einwohnerzahl bebaut werden.

  4. Coherent Detector for Near-Angle Scattering and Polarization Characterization of Telescope Mirror Coatings

    NASA Technical Reports Server (NTRS)

    Macenka, Steven A.; Chipman, Russell A.; Daugherty, Brian J.; McClain, Stephen C.

    2012-01-01

    A report discusses the difficulty of measuring scattering properties of coated mirrors extremely close to the specular reflection peak. A prototype Optical Hetero dyne Near-angle Scatterometer (OHNS) was developed. Light from a long-coherence-length (>150 m) 532-nm laser is split into two arms. Acousto-optic modulators frequency shift the sample and reference beams, establishing a fixed beat frequency between the beams. The sample beam is directed at very high f/# onto a mirror sample, and the point spread function (PSF) formed after the mirror sample is scanned with a pinhole. This light is recombined by a non-polarizing beam splitter and measured through heterodyne detection with a spectrum analyzer. Polarizers control the illuminated and analyzed polarization states, allowing the polarization dependent scatter to be measured. The bidirectional reflective or scattering distribution function is normally measured through use of a scattering goniometer instrument. The instrumental beam width (collection angle span) over which the scatterometer responds is typically many degrees. The OHNS enables measurement at angles as small as the first Airy disk diameter.

  5. Four 1-D metal-organic polymers self-assembled from semi-flexible benzimidazole-based ligand: Syntheses, structures and fluorescent properties

    NASA Astrophysics Data System (ADS)

    Zhou, Chun-lin; Wang, Shi-min; Liu, Sai-nan; Yu, Tian-tian; Li, Rui-ying; Xu, Hong; Liu, Zhong-yi; Sun, Huan; Cheng, Jia-jia; Li, Jin-peng; Hou, Hong-wei; Chang, Jun-biao

    2016-08-01

    Four one-dimensional (1-D) metal-organic polymers based on methylene-bis(1,1‧-benzimidazole)(mbbz), namely, {[Hg(mbbz)(SCN)2]·1/3H2O}n (1), [Co(mbbz)(Cl)2]n (2), {[Co(mbbz)(SO4)]·CH3OH}n (3) and {[Zn(mbbz)(SO4)]·CH3OH}n (4) have been successfully synthesized and structurally characterized. Single-crystal X-ray diffraction reveals that polymers 1 and 2 exhibit interesting 1-D double helical chain structures, while polymers 3 and 4 are 1-D double chain structures due to the bridging effect of mbbz ligands and sulfate anions. These polymers containing the mbbz-based ligand have a high degree of dependence on the corresponding counter anions. Furthermore, the fluorescence properties of the four polymers were also investigated in the solid state, showing the fluorescence signal changes in comparing with that of free ligand mbbz.

  6. Does occupational health nursing exist in India?

    PubMed Central

    Tiwari, Rajnarayan R.; Sharma, Anjali; Zodpey, Sanjay P.; Khandare, Shobha M.

    2014-01-01

    Background: Occupational health services are important to develop healthy and productive work forces, which should be delivered through occupational health team. Occupational health nurse (OHN) is an important member of this team and is required to apply nursing principles in conserving the health of workers in occupational settings. Purpose: This article attempts to map the occupational health nursing courses in India and design competencies and curriculum for such a course. Materials and Methods: Information through the Internet, printed journals, and perspectives of the key stakeholders were the principal sources of data. Discussion: In India, there is a need to initiate a course on occupational health nursing to provide occupational health services for the organized and unorganized sector workforce. A certificate course for occupational health nursing for 3–4 months duration offered through contact session mode can be an opportune beginning. However, to cater employed nurses an online course can be another effective alternative. The theoretical part should essentially include modules on occupational diseases, industrial hygiene, and occupational health legislation, whereas the modules on practical aspects can include visits to industries. Taking into account the existing norms of Indian Factories Act for hazardous units of organized sector an estimated 1,34,640 OHNs are required. Conclusion: There is a need–supply gap in the number of occupational health nursing manpower in India, which can be attributed to the absence of any course to train such manpower. PMID:25598615

  7. Influence of pseudohalide anions on the structural assembly of Cd(II) coordination polymers with 3,4-bis(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole

    NASA Astrophysics Data System (ADS)

    Chen, Jing; Li, Ming-Ze; Sun, Nan; Guo, Jian-Hua

    2016-02-01

    Four CdII coordination polymers, namely {[Cd(L334)(Cl)2](CH3OH)}n (1), [Cd(L334)(Cl)(dca)]n (2), {[Cd(L334)(Cl)1.33(N3)0.67](H2O)}n (3), and {[Cd(L334)(SCN)2(H2O)](H2O)1.5(CH3OH)}n (4), have been synthesized by the conventional reactions of CdCl2 and 3,4-bis(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (L334) or in the presence of different pseudohalides dicyanamide (dca), azide (N3), and thiocyanate (SCN), respectively as auxiliary ligands. Complexes 1-3 exhibit the isostructural 2D layered network structures, whereas complex 4 shows a distinct 2D network with dimeric CdII subunits. The structural discrepancy in 1-4 indicates the significant influence of pseudohalide anions on the structural assembly of CdII coordination polymers with 3,4-bis(3-pyridyl)-5-(4-pyridyl)-1,2,4-triazole. In addition, thermogravimetric and fluorescent properties for all complexes and the ligand have also been investigated.

  8. Informationsqualität - Definitionen, Dimensionen und Begriffe

    NASA Astrophysics Data System (ADS)

    Rohweder, Jan Philipp; Kasten, Gerhard; Malzahn, Dirk; Piro, Andrea; Schmid, Joachim

    Die Verbesserung und Sicherstellung der Informationsqualität wird in immer mehr Unternehmen als eigenständige Managementaufgabe von großer Wichtigkeit begriffen. IQ-Management ist ein elementarer Baustein in Systemintegrationsprojekten. Aber auch in bestehenden Prozessen mit heterogenen Datenquellen und Informationsnutzern ist eine hohe Informationsqualität die Grundvoraussetzung für funktionierende betriebliche Abläufe. Voraussetzung für ein effektives IQ-Management ist die Bewertung der Informationsqualität [Lee et al. 2006, S. 13 und S. 27]. In vielen Unternehmen ist Informationsqualität nur ein gefühlter Wert. Die meisten Anwender bringen ein gewisses Misstrauen den Daten gegenüber zum Ausdruck, dies jedoch ohne genaue Angabe der Fehlerart und -häufigkeit. Nicht selten werden kostspielige Projekte angestoßen, um die Informationsqualität zu verbessern, ohne sich vor einer IQ-Maßnahme durch eine Analyse ein genaues Bild über die tatsächlichen Probleme zu verschaffen. Nur auf der Basis einer umfassenden Bewertung der Informationsqualität können die notwendigen Ressourcenentscheidungen herbeigeführt, Ziele gesetzt und der Erfolg des IQ-Management beurteilt werden.

  9. Photodissociation investigation of doubly charged ethanol clusters induced by inner-shell electron ionization.

    PubMed

    Tamenori, Y; Okada, K; Tabayashi, K; Hiraya, A; Gejo, T; Honma, K

    2011-05-28

    Fragmentation of doubly charged ethanol clusters [(C(2)H(5)OH)(n)] following the O 1s ionization has been investigated by means of the photoelectron-photoion-photoion coincidence (PEPIPICO) method. The dominant fission channel of (C(2)H(5)OH)(n)(2+) was the formation of protonated cluster ion pairs [H(C(2)H(5)OH)(l)(+)/H(C(2)H(5)OH)(m)(+)]. The fragmentation mechanisms of these ion pairs were discussed based on the analysis of the PEPIPICO contour shape. It was clarified that the prominent fragmentation channel was a secondary decay mechanism, where neutral evaporation occurs after charge separation. On the other hand, the formation of small fragment ions was suppressed, excluding the formation of certain specific fragments (H(3)O(+), C(2)H(5)(+)/COH(+), and C(2)H(4)OH(+)). The formation of small fragment ions was suppressed due to the cooling effect caused by the neutral evaporation and the decrease in the electrostatic repulsive force caused by charge separation. PMID:21639435

  10. The Moral Career of 'Outmates': Towards a History of Manufactured Mental Disorders in Post-Socialist China.

    PubMed

    Wu, Harry Yi-Jui

    2016-01-01

    This study focuses on 'manufactured mentally ill' (bei jingshenbing, [symbol in text]) individuals in post-socialist China. In Chinese society, bei jingshenbing is a neologistic catchphrase that refers to someone who has been misidentified as exhibiting symptoms of mental illness and has been admitted to a mental hospital. Specifically, it refers to those individuals who were subjected to unnecessary psychiatric treatment during the first decade of the twenty-first century. Based on archival analysis and ethnographic fieldwork, this study addresses the ways in which the voices of bei jingshenbing victims and those who support them reveal China's experiences with psychiatric modernity. It also discusses the active role of these individuals in knowledge production, medical policymaking, and the implications for reforming the psychiatric and mental health systems in post-socialist China. PMID:26651190

  11. Regenerative Energieträger im Aufwind: Entwicklung der erneuerbaren Energien

    NASA Astrophysics Data System (ADS)

    Kohl, Harald

    2006-05-01

    2005 kam 4,6 % des deutschen Primär-Energieverbrauchs aus erneuerbaren Energiequellen, bei der Stromproduktion lag ihr Anteil bei 10,2 %. Wesentliche Ursache ist der Boom bei der Windkraft, die vor allem durch Offshore-Windparks auf See weiter ausbaubar ist. Die Wasserkraft lieferte in Deutschland traditionell einen großen Beitrag zur Stromerzeugung, doch ihr Ausbaupotenzial ist gering. Die Photovoltaik, die solar- und die geothermische Stromerzeugung spielen derzeit noch eine kleine Rolle. Den deutschen Bedarf an Wärmeenergie deckten 2004 die erneuerbaren Energien zu 5,4 %, vor allem aus Biomasse. Die solarthermische Wärmeerzeugung hat sich gegenüber 2000 mehr als verdoppelt. Im Straßenverkehr spielen biogene Kraftstoffe mit 5,4 % noch eine untergeordnete Rolle. Bis 2050 könnte in Deutschland der Anteil regenerativer Energien am Primär-Energieverbrauch die Fünfzigprozentmarke überschreiten.

  12. The Moral Career of ‘Outmates’: Towards a History of Manufactured Mental Disorders in Post-Socialist China

    PubMed Central

    Wu, Harry Yi-Jui

    2016-01-01

    This study focuses on ‘manufactured mentally ill’ (bei jingshenbing, 被精神病) individuals in post-socialist China. In Chinese society, bei jingshenbing is a neologistic catchphrase that refers to someone who has been misidentified as exhibiting symptoms of mental illness and has been admitted to a mental hospital. Specifically, it refers to those individuals who were subjected to unnecessary psychiatric treatment during the first decade of the twenty-first century. Based on archival analysis and ethnographic fieldwork, this study addresses the ways in which the voices of bei jingshenbing victims and those who support them reveal China’s experiences with psychiatric modernity. It also discusses the active role of these individuals in knowledge production, medical policymaking, and the implications for reforming the psychiatric and mental health systems in post-socialist China. PMID:26651190

  13. Differentiation of the properties of the branching isozymes from maize (Zea mays)

    SciTech Connect

    Guan, H.P.; Preiss, J. )

    1993-08-01

    The multiple forms of branching enzyme (BE) from developing maize (Zea mays) endosperm were purified by modification of previous procedures such that amylase activity could be eliminated completely from the BE preparation. Three distinct assays for BE activity (phosphorylase a stimulation assay, BE linkage assay, and iodine stain assay) were used to characterize and differentiate that properties of the BE isoforms. This study present s the first evidence that the BE isoforms differ in their action on amylopectin. BEI has the highest activity in branching amylose, but its rate of branching amylopectin was less than 5% of that of branching amylose. Conversely, BEII isoforms had lower rates in branching amylose (about 9--12% of that of BEI) and had higher rates of branching amylopectin (about 6-fold) than BEI. The implication of these findings to the mechanism of amylopectin synthesis in vivo are discussed. 21 refs., 1 figs., 5 tabs.

  14. Implementierungstechniken

    NASA Astrophysics Data System (ADS)

    Lippe, Wolfram-Manfred

    Die klassische Technik zur Implementierung funktionaler und applikativer Sprachen ist die des Interpretierens. Stammvater aller Interpretierer ist der in Kapitel 3.2.2.12 vorgestellte Interpretierer von McCarthy. Das Hauptproblem aller Implementierungstechniken, die Bindung von Werten an Namen, wird bei ihm durch das Konzept der Assoziationsliste (A-Liste) realisiert. Die Elemente dieser Liste sind Paare, deren 1. Komponente aus einem Namen und deren 2. Komponenete aus einem Wert besteht. Anschaulich kann man sich die A-Liste als einen Keller vorstellen, in den bei jeder Bindung eines Wertes an einen Namen, z.B. bei einer Funktions-Deklaration (Label-Deklaration) oder einer Funktionsapplikation, das entsprechende Paar gespeichert wird.

  15. Urinary metabolite levels and symptoms in Filipino workers using organic solvents.

    PubMed

    Cucueco, M T; Espinosa, N C; Villanueva, M B; Castro, F T; Sison, S Y; Ortega, V S; Hisanaga, N

    1993-01-01

    To compare symptoms with urinary metabolite levels, 900 workers from 7 organic solvent-using industries were studied. Urinary metabolites were determined using a high performance liquid chromatograph. Urinary hippuric acid concentrations exceeding the reference value (2.5 g/g creatinine) were found in 78 (8.7%) workers. However, only 3 (0.3%) and 1 (0.1%) of the participants exceeded the reference value for mandelic (0.8 g/g creatinine) and total methylhippuric acid (1.5 g/g creatinine), respectively. The sum of the values of the ratio of measured urinary metabolite concentration to the corresponding ACGIH's biological exposure indices (BEI) [(HA/BEI of HA + MHA/BEI of MHA + MA/BEI of MA)] exceeded 1.0 in 166 (18.4%) workers. Majority of them were from the footwear manufacturing industry (63/129 or 49.2%). Questionnaire interviews were also administered to determine the prevalence of symptoms while at work (acute symptoms) or within the past 6 months (chronic symptoms). Urinary metabolite levels of individual and mixed solvents were compared with the symptoms of all workers. Analysis using Spearman's rank correlation showed in workers whose urinary hippuric acid exceeded 3.75 g/g creatine (1.5 x BEI), significant correlation between their hippuric acid levels and subjective complaints. Workers whose sum of the values of the ratio of measured urinary metabolite concentration to corresponding BEI exceeded 1.5 were selected and comparing this level with their symptoms, significant correlation was also noted in some complaints. PMID:8406919

  16. Abgasnachbehandlung

    NASA Astrophysics Data System (ADS)

    Wirth, Ralf; Raatz, Thorsten

    Bisher wurde die Emissionsminderung beim Dieselmotor vorwiegend durch inner motorische Maßnahmen bewirkt. Bei vielen Diesel-Fahrzeugen werden die vom Motor freigesetzten Emissionen (Rohemissionen) jedoch die zukünftig in Europa, den USA und Japan geltenden Emissionsgrenzwerte überschreiten. Die erforderlichen hohen Minderungsraten lassen sich voraussichtlich nur durch eine effiziente Kombination von innermotorischen und nachmotorischen Maßnahmen erreichen. Analog zur bewährten Vorgehensweise bei Benzinfahrzeugen werden deshalb auch für Dieselfahrzeuge verstärkt Systeme zur Abgas - nachbehandlung (nachmotorische Emis sions minderung) entwickelt.

  17. A study on the immune response of sheep to foot and mouth disease virus vaccine type 'O' prepared with different inactivants and adjuvants.

    PubMed

    Nair, S P; Sen, A K

    1992-10-01

    Foot and mouth disease virus (FMDV) type 'O' was inactivated either with formaldehyde or binaryethyleneimine (BEI). Vaccines were prepared with inactivated virus incorporating aluminum hydroxide gel or mineral oil as an adjuvant. The antibody response in sheep was monitored by serum neutralization and ELISA test for a period of six months. Significant difference in antibody response was not observed between vaccines inactivated with formaldehyde or BEI. On the other hand significant difference in the antibody response was noticed between alhydrogel and oil vaccines. The high titer of antibodies stimulated by oil adjuvant vaccines persisted longer than those of alhydrogel vaccines within the period of study. PMID:1364024

  18. Vom magnetischen Bakterium zur Brieftaube: Geo-Biomagnetismus

    NASA Astrophysics Data System (ADS)

    Winklhofer, Michael

    2004-05-01

    Die Fähigkeit, das Erdmagnetfeld wahrzunehmen und sich an ihm zu orientieren, ist im Tierreich weit verbreitet. Durch welche physikalischen Mechanismen magnetische Sinnesreize in Nervensignale umgesetzt werden, ist jedoch weitgehend ungeklärt. Bei magnetotaktischen Bakterien üben zum Beispiel biogene ferrimagnetische Kristalle als mikroskopische Kompassnadeln ein Drehmoment auf die Zelle aus. Magnetit findet sich im Gewebe zahlreicher Tiere. Doch erst bei zwei Arten, der Brieftaube und der Regenbogenforelle, konnten auch entsprechende Sinneszellen gefunden werden. Diese unterscheiden sich allerdings in ihren magnetischen Eigenschaften fundamental voneinander. Die Identifizierung der physikalischen Mechanismen des Geo-Biomagnetismus bleibt eine Herausforderung für Biophysik und Sinnesphysiologie.

  19. Von Donuts und Zucker: Mit Neutronen biologische Makromoleküle erforschen

    NASA Astrophysics Data System (ADS)

    May, Roland P.

    2003-05-01

    Für die Erforschung von Biomolekülen bieten Neutronen einzigartige Eigenschaften. Vor allem ihre unterschiedliche Wechselwirkung mit dem natürlichen Wasserstoff und seinem schweren Isotop Deuterium ermöglicht tiefe Einblicke in Struktur, Funktion und Dynamik von Proteinen, Nukleinsäuren und Biomembranen. Bei vielen Fragestellungen zur Strukturaufklärung gibt es kaum oder keine Alternative zum Neutron. Das Institut Laue-Langevin trägt Bahnbrechendes zum Erfolg der Neutronen-Methoden in der Biologie bei.

  20. EFFECTS OF A EUROPEAN STYLE ELECTRICAL STIMULATOR FOR POULTRY PROCESSING ON SHEAR VALUES AND COOK YIELD OF BROILER BREASTS PROCESSED

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interest is growing in the U. S. and Europe on the application of pulsed electric current (PEC) to improve poultry meat quality and yield, but European processing and stimulation procedures differ from those used in the U. S. In Europe, carcasses are stimulated after defeathering, contact points bei...

  1. Constraints on mountain building in the northeastern Tibet: Detrital zircon records from synorogenic deposits in the Yumen Basin

    NASA Astrophysics Data System (ADS)

    Wang, Weitao; Zhang, Peizhen; Yu, Jingxing; Wang, Yizhou; Zheng, Dewen; Zheng, Wenjun; Zhang, Huiping; Pang, Jianzhang

    2016-06-01

    The Cenozoic basins and ranges form the high topography of the northeastern Tibet that resulted from the India-Eurasia collision. Sedimentary rocks in the basins provide direct insight into the exhumation history of the ranges and the tectonic processes that led to the northeastward growth of the Tibetan Plateau. In this study, we analyzed and compared detrital zircon U-Pb ages from sands of modern rivers draining the Bei Shan, and North Qilian Shan and sandstones from the Yumen Basin. The zircon age distributions indicate that the strata dated to 24.2-16.7 Ma in the basin were derived from the Bei Shan, and the basin provenance changed rapidly to the North Qilian Shan terrane at ~16 Ma. These results suggest that an early stage of deformation along the Bei Shan at ~24 Ma was replaced by the growth of the North Qilian Shan at ~16 Ma. We conclude that the far-field effect associated with the Indo-Asian collision may result from Oligocene deformation in the Bei Shan, but the emergence of the North Qilian Shan at ~16 Ma could reflect the most recent outward growth of the Tibetan Plateau that may have been caused by the removal of some lithospheric mantle beneath central Tibet.

  2. "In Mathe war ich immer schlecht"

    NASA Astrophysics Data System (ADS)

    Beutelspacher, Albrecht

    Genauso wie bei vielen anderen Er scheinungsformen des Lebens (Philosophie, Musik, Liebe) kann Mathematik nicht eindeutig definiert werden. Jede Definition wäre entweder nichtssagend oder zu einengend. Man kann aber versuchen, Mathematik von verschiedenen Seiten zu beleuchten. Dabei offenbaren sich überraschende und tiefe Einblicke in das Wesen der Mathematik.

  3. Development and Validation of Evaluation Indicators for Teaching Competency in STEAM Education in Korea

    ERIC Educational Resources Information Center

    Kim, Bang-Hee; Kim, Jinsoo

    2016-01-01

    The purpose of this study is to develop and validate the evaluation indicators of teaching competency in STEAM education. The teaching competencies in STEAM education were drawn up utilizing both behavioral event interview (BEI) and a literature review. The initial evaluation indicators were then reviewed by 15 experts and two pilot tests were…

  4. Plasmids containing small subunit ribosomal RNA gene fragments from Babesia bovis and Babesia bigemina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BEI Resources was developed by NIAID as a centralized biological resource center for research reagents to the scientific community (http://www.beiresources.org/). They have a considerable amount of reagents and isolates for parasitologists working with Entamoeba histolytica, Giardia, Toxoplasma, and...

  5. Fazit

    NASA Astrophysics Data System (ADS)

    Murrenhoff, Hubertus

    Die im Rahmen des Sonderforschungsbereiches 442 (SFB 442) erarbeiteten Ergebnisse zeigen die Leistungsfähigkeit tribologischer Systeme bei Verwendung nativer Ester in Kombination mit PVD-Werkstoffverbundschichten. Gegenstand der Untersuchungen waren die tribologischen Systeme einer Werkzeugmaschine, wie z. B. Zahnräder, Wälz- und Spindellager, Kolben einer hydraulischen Pumpe sowie Werkzeuge mit geometrisch bestimmter Schneide und Tiefziehwerkzeuge.

  6. Protothecosis successfully treated with amikacin combined with tetracyclines.

    PubMed

    Zhao, J; Liu, W; Lv, G; Shen, Y; Wu, S

    2004-04-01

    Summary We report a case of protothecosis in an 18-year-old female student caused by Prototheca zopfii successfully treated with amikacin combined with tetracyclines. Zusammenfassung Es wird über eine Protothecose, verursacht durch Prototheca zopfii, bei einer 18-jährigen Studentin berichtet, die erfolgreich mit Amikacin in Kombination mit Tetracyclinen behandelt wurde. PMID:15078433

  7. ENVIRONMENTAL HEALTH

    EPA Science Inventory

    Are you healthy? Is your environment healthy for you? What does it mean to be healthy? Does it mean you're not achy, or that you are not visibly sick? The World Health Organization defines health broadly as a state of physical, mental, and social well-being. This means that bei...

  8. Meeting ESL Needs at Home and at Work.

    ERIC Educational Resources Information Center

    Archer, Carol M.

    This paper presents several aspects of the English-as-a-Second-Language (ESL) program for refugees as it was developed at the Bilingual Educational Institute (BEI), an organization that provides refugee and ESL services in the Houston, Texas area. Background information is provided on the development of the current RSS and ESL classes and the…

  9. TRANSFER OF PESTICIDES FROM SURFACES TO FOODS FOR THE ESTIMATION OF DIETARY EXPOSURE OF CHILDREN

    EPA Science Inventory

    Since small children spend much of their time in contact with contaminated surfaces, residues of pesticides found on floors and other surfaces contribute to their aggregate exposures. Any dislodgeable pesticide residues on hands and surfaces may be transferred to foods while bei...

  10. The immune evasion function of J and Beilong virus V proteins is distinct from that of other paramyxoviruses, consistent with their inclusion in the proposed genus Jeilongvirus.

    PubMed

    Audsley, Michelle D; Marsh, Glenn A; Lieu, Kim G; Tachedjian, Mary; Joubert, D Albert; Wang, Lin-Fa; Jans, David A; Moseley, Gregory W

    2016-03-01

    IFN-antagonist function is a major determinant of pathogenicity and cross-species infection by viruses, but remains poorly defined for many potentially zoonotic viruses resident in animal species. The paramyxovirus family contains several zoonotic viruses, including highly pathogenic viruses such as Nipah virus and Hendra virus, and an increasing number of largely uncharacterized animal viruses. Here, we report the characterization of IFN antagonism by the rodent viruses J virus (JPV) and Beilong virus (BeiPV) of the proposed genus Jeilongvirus of the paramyxoviruses. Infection of cells by JPV and BeiPV was found to inhibit IFN-activated nuclear translocation of signal transducer and activator of transcription 1 (STAT1). However, in contrast to most other paramyxoviruses, the JPV and BeiPV V proteins did not interact with or inhibit signalling by STAT1 or STAT2, suggesting that JPV/BeiPV use an atypical V protein-independent strategy to target STATs, consistent with their inclusion in a separate genus. Nevertheless, the V proteins of both viruses interacted with melanoma differentiation-associated protein 5 (MDA5) and robustly inhibited MDA5-dependent activation of the IFN-β promoter. This supports a growing body of evidence that MDA5 is a universal target of paramyxovirus V proteins, such that the V-MDA5 interaction represents a potential target for broad-spectrum antiviral approaches. PMID:26703878

  11. Accounting for windbreak's climate change contributions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Regional climate change (CC) scenarios call for increased frequency and intensity of drought and storm events. For the North American Great Plains Region this means producers will be even more at the whim of shifting weather patterns and other stressors that may be exacerbated by CC. Options are bei...

  12. Physiknobelei Kann man die Lichtausbreitung sehen?

    NASA Astrophysics Data System (ADS)

    Schlichting, H.-Joachim

    2003-07-01

    Des Menschen Sinne sind trügerisch. Das wussten schon die Philosophen der Antike, denen physikalische Zusammenhänge noch fremd waren. Doch auch in der heutigen aufgeklärten Zeit ereignen sich noch Dinge, bei denen man seinen Augen nicht traut.

  13. IFLA General Conference, 1987. Division of Special Libraries. Science and Technology Libraries Section. Papers.

    ERIC Educational Resources Information Center

    International Federation of Library Associations, The Hague (Netherlands).

    The six papers in this collection focus on science and technology libraries: (1) "Human Aspects of Electronically-Stored Information: The Library User" (A. J. Meadows, United Kingdom); (2) "Untersuchung Menschlicher Aspekte bei den Elektronisch Gespeicherten Informationen: Ansichten des Leiters eines Bibliothekskollektives = Human Aspects of…

  14. Means of Production

    ERIC Educational Resources Information Center

    Raths, David

    2012-01-01

    No one who's worked in higher education will ever confuse the experience with working in the corporate sector. Colleges and universities are simply not geared for the business of manufacturing or marketing products. The focus--as it should be--is on teaching and research. Given the wealth of talent among IT staff and faculty, however, higher ed…

  15. Use of NTRIP for Optimizing the Decoding Algorithm for Real-Time Data Streams

    PubMed Central

    He, Zhanke; Tang, Wenda; Yang, Xuhai; Wang, Liming; Liu, Jihua

    2014-01-01

    As a network transmission protocol, Networked Transport of RTCM via Internet Protocol (NTRIP) is widely used in GPS and Global Orbiting Navigational Satellite System (GLONASS) Augmentation systems, such as Continuous Operational Reference System (CORS), Wide Area Augmentation System (WAAS) and Satellite Based Augmentation Systems (SBAS). With the deployment of BeiDou Navigation Satellite system (BDS) to serve the Asia-Pacific region, there are increasing needs for ground monitoring of the BeiDou Navigation Satellite system and the development of the high-precision real-time BeiDou products. This paper aims to optimize the decoding algorithm of NTRIP Client data streams and the user authentication strategies of the NTRIP Caster based on NTRIP. The proposed method greatly enhances the handling efficiency and significantly reduces the data transmission delay compared with the Federal Agency for Cartography and Geodesy (BKG) NTRIP. Meanwhile, a transcoding method is proposed to facilitate the data transformation from the BINary EXchange (BINEX) format to the RTCM format. The transformation scheme thus solves the problem of handing real-time data streams from Trimble receivers in the BeiDou Navigation Satellite System indigenously developed by China. PMID:25310474

  16. Use of NTRIP for optimizing the decoding algorithm for real-time data streams.

    PubMed

    He, Zhanke; Tang, Wenda; Yang, Xuhai; Wang, Liming; Liu, Jihua

    2014-01-01

    As a network transmission protocol, Networked Transport of RTCM via Internet Protocol (NTRIP) is widely used in GPS and Global Orbiting Navigational Satellite System (GLONASS) Augmentation systems, such as Continuous Operational Reference System (CORS), Wide Area Augmentation System (WAAS) and Satellite Based Augmentation Systems (SBAS). With the deployment of BeiDou Navigation Satellite system(BDS) to serve the Asia-Pacific region, there are increasing needs for ground monitoring of the BeiDou Navigation Satellite system and the development of the high-precision real-time BeiDou products. This paper aims to optimize the decoding algorithm of NTRIP Client data streams and the user authentication strategies of the NTRIP Caster based on NTRIP. The proposed method greatly enhances the handling efficiency and significantly reduces the data transmission delay compared with the Federal Agency for Cartography and Geodesy (BKG) NTRIP. Meanwhile, a transcoding method is proposed to facilitate the data transformation from the BINary EXchange (BINEX) format to the RTCM format. The transformation scheme thus solves the problem of handing real-time data streams from Trimble receivers in the BeiDou Navigation Satellite System indigenously developed by China. PMID:25310474

  17. First-limiting amino acids in soybean-based diets for white seabass Atractoscion nobilis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study aims to identify the limiting amino acids in low fish meal, soy-based diets in juvenile white seabass. Two 8-week trials were conducted. The first trial evaluated three diets containing 36, 18 and 9% fish meal in the diet (FM36, FM18, FM9, respectively), with the last two diets bei...

  18. Constraints on mountain building in the northeastern Tibet: Detrital zircon records from synorogenic deposits in the Yumen Basin.

    PubMed

    Wang, Weitao; Zhang, Peizhen; Yu, Jingxing; Wang, Yizhou; Zheng, Dewen; Zheng, Wenjun; Zhang, Huiping; Pang, Jianzhang

    2016-01-01

    The Cenozoic basins and ranges form the high topography of the northeastern Tibet that resulted from the India-Eurasia collision. Sedimentary rocks in the basins provide direct insight into the exhumation history of the ranges and the tectonic processes that led to the northeastward growth of the Tibetan Plateau. In this study, we analyzed and compared detrital zircon U-Pb ages from sands of modern rivers draining the Bei Shan, and North Qilian Shan and sandstones from the Yumen Basin. The zircon age distributions indicate that the strata dated to 24.2-16.7 Ma in the basin were derived from the Bei Shan, and the basin provenance changed rapidly to the North Qilian Shan terrane at ~16 Ma. These results suggest that an early stage of deformation along the Bei Shan at ~24 Ma was replaced by the growth of the North Qilian Shan at ~16 Ma. We conclude that the far-field effect associated with the Indo-Asian collision may result from Oligocene deformation in the Bei Shan, but the emergence of the North Qilian Shan at ~16 Ma could reflect the most recent outward growth of the Tibetan Plateau that may have been caused by the removal of some lithospheric mantle beneath central Tibet. PMID:27277834

  19. Constraints on mountain building in the northeastern Tibet: Detrital zircon records from synorogenic deposits in the Yumen Basin

    PubMed Central

    Wang, Weitao; Zhang, Peizhen; Yu, Jingxing; Wang, Yizhou; Zheng, Dewen; Zheng, Wenjun; Zhang, Huiping; Pang, Jianzhang

    2016-01-01

    The Cenozoic basins and ranges form the high topography of the northeastern Tibet that resulted from the India-Eurasia collision. Sedimentary rocks in the basins provide direct insight into the exhumation history of the ranges and the tectonic processes that led to the northeastward growth of the Tibetan Plateau. In this study, we analyzed and compared detrital zircon U-Pb ages from sands of modern rivers draining the Bei Shan, and North Qilian Shan and sandstones from the Yumen Basin. The zircon age distributions indicate that the strata dated to 24.2-16.7 Ma in the basin were derived from the Bei Shan, and the basin provenance changed rapidly to the North Qilian Shan terrane at ~16 Ma. These results suggest that an early stage of deformation along the Bei Shan at ~24 Ma was replaced by the growth of the North Qilian Shan at ~16 Ma. We conclude that the far-field effect associated with the Indo-Asian collision may result from Oligocene deformation in the Bei Shan, but the emergence of the North Qilian Shan at ~16 Ma could reflect the most recent outward growth of the Tibetan Plateau that may have been caused by the removal of some lithospheric mantle beneath central Tibet. PMID:27277834

  20. A Comprehensive Cultural Orientation Program for Refugees.

    ERIC Educational Resources Information Center

    Archer, Carol M.

    This paper presents the various components of the cultural orientation program as it has developed at the Bilingual Educational Institute (BEI), the organization that is currently awarded the grant for RSS in the Houston area by the state of Texas. This cultural orientation program's topics include the following: employment; healthcare; community…

  1. Spreading culm locus discovered while dissecting a sheath blight resistance QTL within a set of TeQing-into-Lemont introgression lines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new gene-mapping population comprised of 123 TeQing-into-Lemont backcross introgression lines (TILs) was developed for the purpose of providing a uniquely efficient avenue for verifying, molecularly tagging, and incorporating desired TeQing QTL into improved U.S. rice varieties. The TILs were bei...

  2. Evaluating Theobroma grandiflorum for comparative genomic studies with Theobroma cacao

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The seeds of Theobroma cacao (cacao) are the source of cocoa, the raw material for the multi-billion dollar chocolate industry. Cacao’s two most important traits are its unique seed storage triglyceride (cocoa butter) and the flavor of its fermented beans (chocolate). The genome of T. cacao is bei...

  3. Investigation of Moisture Interaction with Cellulose Using Solid-State NMR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The interaction of water with cellulose and its influence on the nuclear spin dynamics in Gossypium barbadense (Pima) cotton were investigated by 1H and 13C solid-state NMR techniques. 1H spin diffusion results indicate that water is present in multiple layers within the cotton fiber, each layer bei...

  4. Analytik von Lebensmittelallergenen

    NASA Astrophysics Data System (ADS)

    Demmel, Anja; Hahn, Alexandra

    Ansonsten harmlose Lebensmittel oder deren Bestandteile können bei von Lebensmittelallergien betroffenen Personen Überempfindlichkeitsreaktionen auslösen. Hierbei kann es sich um immunvermittelte Lebensmittelallergien oder um Intoleranzen gegenüber bestimmten Lebensmittelbestandteilen handeln. Ein Beispiel für Letzteres ist die Laktoseintoleranz, welche durch einen Enzymdefekt hervorgerufen wird [1]. Im Gegensatz hierzu handelt es sich bei Lebensmittelallergien um Sofortreaktionen, die durch IgE-Antikörper gegen Antigene aus den Lebensmitteln hervorgerufen werden und zu verschiedenen körperlichen Beschwerden führen können. Bei den Antigenen, welche von den von Allergikern produzierten IgE-Antikörpern erkannt werden, handelt es sich vor allem um Proteine [2]. Symptome IgE-vermittelter Reaktionen können zum Beispiel Hautausschlag, eine Schwellung der Schleimhäute oder das sogenannte orale Allergiesyndrom mit allergischen Reaktionen an der Mundschleimhaut und im Magen-Darm-Trakt sein [3]. Die hierbei auftretenden Beschwerden reichen von einem Brennen im Mund und einer Schwellung der Lippen und der Zunge bis zu Atemnot verursachenden Schwellungen im Kehlkopfbereich. In besonders schlimmen Fällen können allergische Reaktionen zu einem anaphylaktischen Schock und zum Tod durch Kreislaufversagen führen [4]. Während klassische Nahrungsallergene häufig komplexe Reaktionen zur Folge haben, ist bei Pollen-assoziierten Nahrungsmittelallergien das orale Allergiesyndrom vorherrschend.

  5. Professional Relevance in a Multilingual World

    ERIC Educational Resources Information Center

    Silver, Rita

    2009-01-01

    In renewing her TESOL membership for 2008, the author noted that the membership letter stated that TESOL is a "global professional organization for English language educators." This was of particular interest as she prepared for TESOL's Bilingual Education Interest Section (BEIS) 2008 session titled "Imagining Multilingual TESOL," because on a…

  6. Industry-Oriented Competency Requirements for Mechatronics Technology in Taiwan

    ERIC Educational Resources Information Center

    Shyr, Wen-Jye

    2012-01-01

    This study employed a three-phase empirical method to identify competency indicators for mechatronics technology according to industry-oriented criteria. In Phase I, a list of required competencies was compiled using Behavioral Event Interviews (BEI) with three engineers specializing in the field of mechatronics technology. In Phase II, the Delphi…

  7. Oberflächenphysik Heiße Elektronen

    NASA Astrophysics Data System (ADS)

    Nienhaus, Hermann

    2002-03-01

    Auf welchem Wege wird Energie, die bei exothermen, chemischen Reaktionen an Metalloberflächen frei wird, in Wärme umgewandelt? Ein deutsch-amerikanisches Wissenschaftlerteam gab auf diese Frage eine erste Antwort. Ihm gelang unter Verwendung von einfachen, elektronischen Bauelementen der direkte Nachweis von heißen Ladungsträgern, die durch chemische Reaktionen angeregt werden.

  8. Magnus Strandqvist: 50th anniversary of his doctoral thesis.

    PubMed

    Kajanti, M J

    1994-01-01

    This article is dedicated to Magnus Strandqvist's famous doctoral thesis "Studien über die kumulative Wirkung der Röntgenstrahlen bei Fraktionierung. Erfahrungen aus dem Radiumhemmet an 280 Haut- und Lippenkarzinomen" published in Acta Radiologica in 1944. After a short biography of Strandqvist some central points of his work and their influence on future development of modern radiotherapy are presented. PMID:7993639

  9. Anti-Inflammatory Activity of N-Butanol Extract from Ipomoea stolonifera In Vivo and In Vitro

    PubMed Central

    Zhong, Shuping; Ji, Bin; Wang, Jinzhi; Bai, Xueting; Shi, Ganggang

    2014-01-01

    Ipomoea stolonifera (I. stolonifera) has been used for the treatment of inflammatory diseases including rheumatism and rheumatoid arthritis in Chinese traditional medicine. However, the anti-inflammatory activity of I. stolonifera has not been elucidated. For this reason, the anti-inflammatory activity of n-butanol extract of I. stolonifera (BE-IS) was evaluated in vivo by using acute models (croton oil-induced mouse ear edema, carrageenan-induced rat paw edema, and carrageenan-induced rat pleurisy) and chronic models (cotton pellet-induced rat granuloma, and complete Freund’s adjuvant (CFA)-induced rat arthritis). Results indicated that oral administration of BE-IS significantly attenuated croton oil-induced ear edema, decreased carrageenan-induced paw edema, reduced carrageenan-induced exudates and cellular migration, inhibited cotton pellet-induced granuloma formation and improved CFA-induced arthritis. Preliminary mechanism studies demonstrated that BE-IS decreased the levels of myeloperoxidase (MPO) and malondialdehyde (MDA), increased the activity of anti-oxidant enzyme superoxide dismutase (SOD) in vivo, and reduced the production of nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6 in lipopolysaccharide-activated RAW264.7 macrophages in vitro. Results obtained in vivo and in vitro demonstrate that BE-IS has considerable anti-inflammatory potential, which provided experimental evidences for the traditional application of Ipomoea stolonifera in inflammatory diseases. PMID:24752203

  10. Preliminary study of children's exposure to PAHs and its association with 8-hydroxy-2'-deoxyguanosine in Guangzhou, China.

    PubMed

    Fan, Ruifang; Wang, Dongli; Mao, Chuanwei; Ou, Shangkang; Lian, Zhixia; Huang, Shaoling; Lin, Qiongshan; Ding, Runhao; She, Jianwen

    2012-07-01

    Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous air pollutants generated mainly from incomplete combustion such as automobile exhaust and cigarette smoke. Oxidative stress is believed to be involved in carcinogenesis, and urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) was used as the biomarker to assess such DNA damage. The children's urinary PAH metabolite (OH-PAHs) level were explored in Guangzhou and their associations with 8-OHdG. Two groups of subjects were selected: (1) one group (n=39, 6-7 years old) from an elementary school situated near a heavy traffic road (polluted area) and (2) another group (n=35, 4-6 years old) from a kindergarten situated in a corner of the main campus of a big university (non-polluted area). Urinary 8-OHdG and nine urinary monohydroxylated PAH metabolites were measured, including 2-hydroxynaphthalene (2-OHN), 2-hydroxyfluorene (2-OHF), 2-, 3-, 4-, 9-hydroxyphenanthrene (2-, 3-, 4-, 9-OHPhe), 1-hydroxypyrene (1-OHP), 6-hydroxychrysene (6-OHChr) and 3-hydroxybenzo(a)pyrene (3-OHBaP). All other PAH metabolites were detected in urine samples from both children groups except for 6-OHChr and 3-OHBaP. Levels of 2-OHN, 2-OHF, 3-OHPhe, 9-OHPhe and 1-OHP were significantly different between two groups (P<0.05, T-test). The elementary school children from the polluted area had higher urinary levels of 2-OHN, 2-OHF, 2-, 3-, 4-OHPhe and 1-OHP ((9.10±7.39, 3.72±2.91, 0.32±0.50, 0.37±0.28, 0.23±0.29 and 0.64±0.07 μmol/mol creatinine, respectively) than those from the control group. The results suggested that heavy traffic pollution led to higher PAH body burden. There existed no significant difference for urinary 8-OHdG concentration between two groups (p>0.05, T-test), and no strong correlations between the individual OH-PAHs and 8-OHdG. However, the urinary 8-OHdG concentration in the elementary school children from the traffic polluted area was slightly higher than those in the non-polluted area (20.87±14.42 μmol/mol creatinine

  11. Competition of hydrogen bonds and halogen bonds in complexes of hypohalous acids with nitrogenated bases.

    PubMed

    Alkorta, Ibon; Blanco, Fernando; Solimannejad, Mohammad; Elguero, Jose

    2008-10-30

    A theoretical study of the complexes formed by hypohalous acids (HOX, X = F, Cl, Br, I, and At) with three nitrogenated bases (NH 3, N 2, and NCH) has been carried out by means of ab initio methods, up to MP2/aug-cc-pVTZ computational method. In general, two minima complexes are found, one with an OH...N hydrogen bond and the other one with a X...N halogen bond. While the first one is more stable for the smallest halogen derivatives, the two complexes present similar stabilities for the iodine case and the halogen-bonded structure is the most stable one for the hypoastatous acid complexes. PMID:18837495

  12. Vorausschauend Planen, Gezielt Handeln — Über Die Regelung Und Steuerung Technischer Prozesse

    NASA Astrophysics Data System (ADS)

    Grüne, Lars; Sager, Sebastian; Allgöwer, Frank; Bock, Hans Georg; Diehl, Moritz

    Seit Beginn der industriellen Revolution nimmt die Steuerungs- und Regelungstechnik eine Schlüsselstellung in vielen technischen Bereichen ein. James Watts Fliehkraftregler für Dampfmaschinen ist eines der frühen Beispiele eines extrem erfolgreichen Reglerkonzepts, von dem Ende der 1860er Jahre geschätzte 75000 Exemplare allein in England im Einsatz waren [2, S. 24]. Etwa um diese Zeit begannen Ingenieure, motiviert durch die immer höhere Komplexität der zu regelnden Maschinen, sich systematisch mit theoretischen Grundlagen der Regelung zu beschäftigen. Dies führte unausweichlich zu der Einsicht, dass das dynamische Verhalten der geregelten Systeme nur mit Hilfe der Mathematikverstanden und weiterentwickelt werden konnte, oder wie Werner von Siemens, ein weiterer technischer Pionier in diesem Bereich es formulierte: "Ohne Mathematik tappt man doch immer im Dunkeln.“

  13. Spectroscopic properties of pharmacologically active phenols

    NASA Astrophysics Data System (ADS)

    Tolstorozhev, G. B.; Skornyakov, I. V.; Bel'kov, M. V.; Shadyro, O. I.; Polozov, G. I.; Sorokin, V. L.; Ksendzova, G. A.

    2012-05-01

    The IR Fourier-transform spectra of pharmacologically active phenol molecules in solutions in CCl4 and in the crystalline state have been studied. Phenol derivatives with different directivities and different levels of pharmacological efficiency have been examined. Based on analysis of the IR spectra of screened phenols, the antimicrobial activity of phenols with free hydroxyl groups has been shown to be highest. The high antimicrobial activity of aminophenols is related to the formation of intramolecular hydrogen bonds. For aminophenols that are active against herpesviruses, O-H...N hydrogen bonds are formed in molecules. The main characteristic of the high antiviral activity against A-type influenza is predominance of intramolecular hydrogen bonds of the O-H...O=C type in molecules. Sulfur-containing aminophenols, which manifest activity against HIV infection, are characterized by the occurrence of hydrogen bonds that involve the participation of the OH, NH, and SO2 groups.

  14. Characterization of wine with PTR-MS

    NASA Astrophysics Data System (ADS)

    Boscaini, Elena; Mikoviny, Tomas; Wisthaler, Armin; Hartungen, Eugen Von; Märk, Tilmann D.

    2004-12-01

    A new method for measuring volatile profiles of alcoholic beverages (or other ethanol-containing analytes such as perfumes or herbs) has been developed. The method is based on proton transfer reaction mass spectrometry (PTR-MS). However, instead of hydronium ions (H3O+) protonated ethanol clusters (C2H5OH2+(C2H5OH)n = 1,2) are used as chemical ionization reagent ions. A stable reagent ion distribution is obtained by a 10-fold dilution of analyte headspace into ethanol-saturated nitrogen. Samples with different ethanol content can thus be directly compared. Characteristic mass spectral fingerprints have been obtained for four wine varieties. Principal component analysis discriminates between different wine varieties and shows specific correlations between wine variety and selected ions.

  15. Poly[(μ-1,3-thio-cyanato-κN,S)(iso-nicotin-ato-κN,O)(ethanol-κO)cadmium(II)].

    PubMed

    Neumann, Tristan; Werner, Julia; Jess, Inke; Näther, Christian

    2012-11-01

    In the crystal structure of the title compound, [Cd(NCS)(C(6)H(4)NO(2))(C(2)H(5)OH)](n), the Cd(2+) cation is coordinated by one N and two O atoms of two symmetry-related isonicotinate anions, one ethanol mol-ecule and two μ-1,3-bridging thio-cyanate anions in a distorted octa-hedral N(2)O(3)S geometry. The metal cations are μ-1,3-bridged via thio-cyanate anions into chains that are further connected into layers parallel to the ab plane by bridging isonicotinate anions. The layers are stacked along the c axis. The crystal structure is stabilized by O-H⋯O hydrogen bonds. PMID:23284329

  16. Poly[(μ-1,3-thio­cyanato-κN,S)(iso­nicotin­ato-κN,O)(ethanol-κO)cadmium(II)

    PubMed Central

    Neumann, Tristan; Werner, Julia; Jess, Inke; Näther, Christian

    2012-01-01

    In the crystal structure of the title compound, [Cd(NCS)(C6H4NO2)(C2H5OH)]n, the Cd2+ cation is coordinated by one N and two O atoms of two symmetry-related isonicotinate anions, one ethanol mol­ecule and two μ-1,3-bridging thio­cyanate anions in a distorted octa­hedral N2O3S geometry. The metal cations are μ-1,3-bridged via thio­cyanate anions into chains that are further connected into layers parallel to the ab plane by bridging isonicotinate anions. The layers are stacked along the c axis. The crystal structure is stabilized by O—H⋯O hydrogen bonds. PMID:23284329

  17. Ein mobiler und offener Kernspintomograph: Kernspintomographie für Medizin und Materialforschung

    NASA Astrophysics Data System (ADS)

    Blümich, Bernhard; Kölker, Christian; Casanova, Federico; Perlo, Juan; Felder, Jörg

    2005-09-01

    An der RWTH Aachen wurde der erste offene und mobile Kernspintomograph entwickelt. Anders als die normalerweise riesigen und unbeweglichen Geräte besitzt er keine enge Magnetröhre. So kann er auch in große Untersuchungsobjekte hinein schauen, ohne dass diese zerstört werden müssen. Wie eine Lupe erfasst er dabei ein begrenztes Volumen um den Aufsatzpunkt herum. Neben der Medizin ermöglicht der offene Tomograph viele neue Anwendungsgebiete, vor allem in der Materialprüfung und Qualitätskontrolle. Der Aachener Prototyp kann auch das Fließprofil und die Geschwindigkeitsverteilung strömender Flüssigkeiten sichtbar machen. Sein offenes Prinzip erforderte neue technische Komponenten und modifizierte bildgebende Verfahren. Die Messzeit pro Bild kann heute schon unter einer Viertelstunde liegen.

  18. Das mechatronische Fahrwerk der Zukunft

    NASA Astrophysics Data System (ADS)

    Rieth, Peter

    Technologiesprünge gab es immer wieder in der Geschichte der Automobiltechnologie, so auch in der Kraftfahrzeugbremse, die seit ihren Anfängen eine stete Weiterentwicklung erfahren hat (Bild 40-1). So erlangten schon mechanische Bremsen durchaus ein hohes Niveau, ehe die Hydraulik Mitte der zwanziger Jahre für Komfort und Sicherheit vollkommen neue Perspektiven eröffnete, welche durch Einführung der Hilfskraft(servo)bremsanlagen Mitte des letzten Jahrhunderts noch erweitert wurden. Den wichtigsten Technologiesprung, den der Kunde als Fortschritt erkennt und dementsprechend honoriert, ermöglichte die Elektronik Mitte der siebziger Jahre. ABS, ASR, EBV und nicht zuletzt ESC wären ohne sie nicht vorstellbar.

  19. catena-Poly[[lead(II)-μ-(2-oxidobenz­aldehyde isonicotinoylhydrazonato)] methanol monosolvate

    PubMed Central

    Shahverdizadeh, Gholam Hossein; Ng, Seik Weng; Tiekink, Edward R. T.; Mirtamizdoust, Babak

    2011-01-01

    The Pb atom in the polymeric title compound, {[Pb(C13H9N3O2)]·CH3OH}n, is five-coordinated within an N2O2 donor set and a lone pair of electrons, as the N-isonicotinamido­salicylaldiminate ligand coordinates the PbII atom via the O,N,O′-donors and simultaneously bridges a neighbouring Pb atom via the pyridine N atom; the coordination geometry is based on a trigonal bipyramid with the O atoms in axial positions. The resulting supra­molecular chain is a 31 helix along the c axis. These chains are linked via inter­molecular Pb⋯O,N inter­actions, as well as O—H⋯O hydrogen bonds. PMID:22219816

  20. Infrared photodissociation of size-selected methanol clusters

    NASA Astrophysics Data System (ADS)

    Buck, U.; Gu, X. J.; Lauenstein, Ch.; Rudolph, A.

    1990-05-01

    Size-selective IR photodissociation spectra of (CH3OH)n clusters from n = 2 to n = 9 near the absorption band of the C-O stretching mode of the monomer at 1033.5/cm were measured using an experimental apparatus with a CW CO2 laser collinear to the size-selected cluster beam. The observed spectral features vary from dimer to octamer, with a special transition from the pentamer to the hexamer. An intermolecular model potential is used to derive a correlation between the observed spectra and the cluster configuration of minimum energy. The results show that only internally excited dimers and trimers can be dissociated with one or two CO2 laser photons, respectively.

  1. Employing linear tetranuclear [Zn4(COO)4(OH)2] clusters as building subunits to construct a new Zn(II) coordination polymer with tunable luminescent properties

    NASA Astrophysics Data System (ADS)

    Li, Wu-Wu; Zhang, Zun-Ting

    2016-02-01

    A new Zn(II) coordination polymer, [Zn2(btc) (biimpy) (OH)]n (1 H3btc = 1,3,5-benzenetricarboxylic acid, biimpy = 2,6-bis(1-imdazoly)pyridine) has been successfully synthesized and characterized by elemental analysis, powder single crystal X-ray diffraction analyses. Compound 1 features a 3D framework employing linear tetranuclear [Zn4(COO)4(OH)2] cluster as building subunits. Topological analysis reveals it represents a (3,10)-connected structural topology by viewing btc3-, linear tetranuclear clusters and biimpy as 3-connected nodes, 10-connected nodes, linear linkers, respectively. Moreover, the thermal stability and luminescent property of compound 1 have been well investigated.

  2. Deep-reasoning fault diagnosis - An aid and a model

    NASA Technical Reports Server (NTRS)

    Yoon, Wan Chul; Hammer, John M.

    1988-01-01

    The design and evaluation are presented for the knowledge-based assistance of a human operator who must diagnose a novel fault in a dynamic, physical system. A computer aid based on a qualitative model of the system was built to help the operators overcome some of their cognitive limitations. This aid differs from most expert systems in that it operates at several levels of interaction that are believed to be more suitable for deep reasoning. Four aiding approaches, each of which provided unique information to the operator, were evaluated. The aiding features were designed to help the human's casual reasoning about the system in predicting normal system behavior (N aiding), integrating observations into actual system behavior (O aiding), finding discrepancies between the two (O-N aiding), or finding discrepancies between observed behavior and hypothetical behavior (O-HN aiding). Human diagnostic performance was found to improve by almost a factor of two with O aiding and O-N aiding.

  3. Investigation of original preasphaltene and asphaltene in coal

    SciTech Connect

    Gao, J.; Yan, Y.; Chen, C.; Li, W.

    1997-12-31

    The preasphaltene (PA) and asphaltene (A) from untreated coal show a direct relationship of PA/A (w/w) to the carbon content of coal. Their thermal stability was investigated by in-situ pyrolysis FTIR, and the results show that PA is more stable than A. Five types of hydrogen bonds formed by hydroxyl were observed by means of vacuum FTIR, and their thermal stability was found to be OH{pi} < self-associated OH < OH-ether {le} tightly bonded cyclic OH {approx_equal} OHN. The insolubility of PA in benzene and A in hexane was determined by the hydrogen bonding associated strength of acid/base components in them, but not their structure parameters and molecular weight. The acid/base associated strength of preasphaltene and asphaltene is estimated in the following ranges, asphaltene, < 5.15kJ/mol; preasphaltene, 5.15--30.9kJ/mol.

  4. Analysis of an Online Match Discussion Board: Improving the Otolaryngology—Head and Neck Surgery Match

    PubMed Central

    Kozin, Elliott D.; Sethi, Rosh; Lehmann, Ashton; Remenschneider, Aaron K.; Golub, Justin S.; Reyes, Samuel A.; Emerick, Kevin; Lee, Daniel J.; Gray, Stacey T.

    2015-01-01

    Introduction “The Match” has become the accepted selection process for graduate medical education. Otomatch.com has provided an online forum for Otolaryngology-Head and Neck Surgery (OHNS) Match-related questions for over a decade. Herein, we aim to 1) delineate the types of posts on Otomatch to better understand the perspective of medical students applying for residency and 2) provide recommendations to potentially improve the Match process. Methods Discussion forum posts on Otomatch between December 2001 and April 2014 were reviewed. The title of each thread and total number of views were recorded for quantitative analysis. Each thread was organized into one of six major categories and one of eighteen subcategories, based on chronology within the application cycle and topic. National Resident Matching Program (NRMP) data were utilized for comparison. Results We identified 1,921 threads corresponding to over 2 million page views. Over 40% of threads related to questions about specific programs, and 27% were discussions about interviews. Views, a surrogate measure for popularity, reflected different trends. The majority of individuals viewed posts on interviews (42%), program specific questions (20%) and how to rank programs (11%). Increase in viewership tracked with a rise in applicant numbers based on NRMP data. Conclusions Our study provides an in depth analysis of a popular discussion forum for medical students interested in the OHNS Match. The most viewed posts are about interview dates and questions regarding specific programs. We provide suggestions to address unmet needs for medical students and potentially improve the Match process. PMID:25550223

  5. Biological applications of hydrophilic C60 derivatives (hC60s)- a structural perspective.

    PubMed

    Zhu, Xiaolei; Sollogoub, Matthieu; Zhang, Yongmin

    2016-06-10

    Reactive oxygen species (ROS) generation and radical scavenging are dual properties of hydrophilic C60 derivatives (hC60s). hC60s eliminate radicals in dark, while they produce reactive oxygen species (ROS) in the presence of irradiation and oxygen. Compared to the pristine C60 suspension, the aqueous solution of hC60s is easier to handle in vivo. hC60s are diverse and could be placed into two general categories: covalently modified C60 derivatives and pristine C60 solubilized non-covalently by macromolecules. In order to present in detail, the above categories are broken down into 8 parts: C60(OH)n, C60 with carboxylic acid, C60 with quaternary ammonium salts, C60 with peptide, C60 containing sugar, C60 modified covalently or non-covalently solubilized by cyclodextrins (CDs), pristine C60 delivered by liposomes, functionalized C60-polymer and pristine C60 solubilized by polymer. Each hC60 shows the propensity to be ROS producer or radical scavenger. This preference is dependent on hC60s structures. For example, major application of C60(OH)n is radical scavenger, while pristine C60/γ-CD complex usually serves as ROS producer. In addition, the electron acceptability and innate hydrophobic surface confer hC60s with O2 uptake inhibition, HIV inhibition and membrane permeability. In this review, we summarize the preparation methods and biological applications of hC60s according to the structures. PMID:27049677

  6. Precise Point Positioning Using Triple GNSS Constellations in Various Modes.

    PubMed

    Afifi, Akram; El-Rabbany, Ahmed

    2016-01-01

    This paper introduces a new dual-frequency precise point positioning (PPP) model, which combines the observations from three different global navigation satellite system (GNSS) constellations, namely GPS, Galileo, and BeiDou. Combining measurements from different GNSS systems introduces additional biases, including inter-system bias and hardware delays, which require rigorous modelling. Our model is based on the un-differenced and between-satellite single-difference (BSSD) linear combinations. BSSD linear combination cancels out some receiver-related biases, including receiver clock error and non-zero initial phase bias of the receiver oscillator. Forming the BSSD linear combination requires a reference satellite, which can be selected from any of the GPS, Galileo, and BeiDou systems. In this paper three BSSD scenarios are tested; each considers a reference satellite from a different GNSS constellation. Natural Resources Canada's GPSPace PPP software is modified to enable a combined GPS, Galileo, and BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets collected at four different IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the International GNSS Service Multi-GNSS Experiment (IGS-MGEX) network are used to correct the GPS, Galileo, and BeiDou measurements in the post-processing PPP mode. A real-time PPP solution is also obtained, which is referred to as RT-PPP in the sequel, through the use of the IGS real-time service (RTS) for satellite orbit and clock corrections. However, only GPS and Galileo observations are used for the RT-PPP solution, as the RTS-IGS satellite products are not presently available for BeiDou system. All post-processed and real-time PPP solutions are compared with the traditional un-differenced GPS-only counterparts. It is shown that combining the GPS, Galileo, and BeiDou observations in the post-processing mode improves the PPP convergence

  7. Precise Point Positioning Using Triple GNSS Constellations in Various Modes

    PubMed Central

    Afifi, Akram; El-Rabbany, Ahmed

    2016-01-01

    This paper introduces a new dual-frequency precise point positioning (PPP) model, which combines the observations from three different global navigation satellite system (GNSS) constellations, namely GPS, Galileo, and BeiDou. Combining measurements from different GNSS systems introduces additional biases, including inter-system bias and hardware delays, which require rigorous modelling. Our model is based on the un-differenced and between-satellite single-difference (BSSD) linear combinations. BSSD linear combination cancels out some receiver-related biases, including receiver clock error and non-zero initial phase bias of the receiver oscillator. Forming the BSSD linear combination requires a reference satellite, which can be selected from any of the GPS, Galileo, and BeiDou systems. In this paper three BSSD scenarios are tested; each considers a reference satellite from a different GNSS constellation. Natural Resources Canada’s GPSPace PPP software is modified to enable a combined GPS, Galileo, and BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets collected at four different IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the International GNSS Service Multi-GNSS Experiment (IGS-MGEX) network are used to correct the GPS, Galileo, and BeiDou measurements in the post-processing PPP mode. A real-time PPP solution is also obtained, which is referred to as RT-PPP in the sequel, through the use of the IGS real-time service (RTS) for satellite orbit and clock corrections. However, only GPS and Galileo observations are used for the RT-PPP solution, as the RTS-IGS satellite products are not presently available for BeiDou system. All post-processed and real-time PPP solutions are compared with the traditional un-differenced GPS-only counterparts. It is shown that combining the GPS, Galileo, and BeiDou observations in the post-processing mode improves the PPP convergence

  8. Effects of Three Types of Inactivation Agents on the Antibody Response and Immune Protection of Inactivated IHNV Vaccine in Rainbow Trout.

    PubMed

    Tang, Lijie; Kang, Haiyan; Duan, Kexin; Guo, Mengting; Lian, Gaihong; Wu, Yang; Li, Yijing; Gao, Shuai; Jiang, Yanping; Yin, Jiyuan; Liu, Min

    2016-09-01

    Infectious hematopoietic necrosis virus (IHNV) infects salmonid fish, resulting in high mortality and serious economic losses to salmonid aquaculture. Therefore, an effective IHNV vaccine is urgently needed. To select an inactivation agent for the preparation of an effective IHNV vaccine, rainbow trout were immunized with mineral oil emulsions of IHNV vaccines inactivated by formaldehyde, binary ethylenimine (BEI), or β-propiolactone (BPL). The fish were challenged 8 weeks after vaccination, and their IgM antibody response and relative percent survival (RPS) were evaluated. The results show that formaldehyde, BEI, and BPL abolished IHNV HLJ-09 infectivity within 24, 48, and 24 h at final concentrations of 0.2%, 0.02%, and 0.01%, respectively. The mean levels of specific IgM, both in serum and mucus (collected from the skin surface and gills), for the three immunized groups (from high to low) ranked as follows: the BPL group, BEI group, and formaldehyde group. From weeks 5 to 9, the mean log2 serum titers of IgM in the BPL group were significantly higher compared with those of the other groups (p < 0.05) during the 9 weeks of observation after vaccination (immunized at weeks 0 and6). Mucus OD490 values of the BPL group were significantly higher compared with those of the other groups (p < 0.05) when reaching their peak at weeks 5 and 8, but the difference between the formaldehyde and BEI groups was not significant (p > 0.05). The BPL-inactivated whole-virus vaccine had the greatest protective effect on the rainbow trout after challenge by an intraperitoneal injection of live IHNV, with an RPS rate of 91.67%, which was significantly higher compared with the BEI (83.33%) and formaldehyde (79.17%) groups. These results indicate that the BPL-inactivated IHNV oil-adjuvant vaccine was more effective than the formaldehyde- or BEI-inactivated vaccines. The results of this study provide an important foundation for further studies on inactivated IHNV vaccines

  9. Ejnar Hertzsprung

    NASA Astrophysics Data System (ADS)

    Herrmann, Dieter B.

    Mit diesem Werk von D.B. Herrmann, dem bekannten Astronomiehistoriker und Direktor der Archenhold-Sternwarte und des Zeiss-Großplanetariums in Berlin, liegt zum ersten Mal eine umfassende Biographie des großen Astronomen Ejnar Hertzsprung vor. Ejnar Hertzsprung (1873-1967) verdanken wir die Entdeckung der Riesen- und Zwergsterne, Grundlage für das sog. Hertzsprung-Russel-Diagramm, das eine zentrale Rolle bei der Erforschung der Sternentwicklung spielt. Er bearbeitete erfolgreich Doppelsterne und Veränderliche Sterne und trug Entscheidendes zur modernen Astrophysik bei. Wenig bekannt ist sein Leben, das hier unter Benutzung von Arbeitsmaterial, Interviews mit Zeitgenossen, des Familienarchivs und von Sekundärliteratur von einem kundigen Fachmann beschrieben wird. In D.B. Herrmanns Buch wird nicht nur Persönlichkeit und Werk von Hertzsprung lebendig, sondern auch die astronomische Forschung seiner Zeit. Dieser wertvolle Beitrag zur Wissenschaftsgeschichte wendet sich auch an eine breite allgemeine Leserschaft.

  10. Bewegungsapparat: Postcraniales Skelett und Muskulatur

    NASA Astrophysics Data System (ADS)

    Fischer, Martin S.

    Der Bewegungsapparat bestimmt die Form des Wirbeltierkörpers. So lässt sich z. B. aus der Gestalt eines Fisches auf seine bevorzugt e Schwimmweise schließen (S. 61). Bei den aquatisch en Schädeltieren dominiert die Fortbewegung mit axialem Antrieb; bei den meisten Tetrapoda findet sich eine Kombination aus axialem Antrieb und Bewegung durch Gliedmaßen. Selbst beim höchst spezialisierten Gang, der bipeden Bewegung des Menschen, sind Torsionsbewegungen des Rumpfes noch maßgeblich und bestimmen auch die Grundform des menschlichen Körpers (z. B. die Taille). Obwohl die verschiedenen Antriebsmechanismen eine funktionelle Einheit bilden, werden im Folgenden das Axialskelett sowie der Schulter- und Beckengürtel mit den zugehörigen Extremitäten getrennt besprochen.

  11. Automatische Montagemaschinen

    NASA Astrophysics Data System (ADS)

    Hesse, Stefan

    Seit den 1950er Jahren werden Produkte in größerem Ausmaß automatisch montiert. Besonders bei ausgesprochenen Massenprodukten wurde inzwischen ein hoher technischer Stand erreicht. Die dazu benutzten Montageautomaten sind Sondermaschinen, die fur ein Produkt individuell angepasst sind. Typisch sind mittlerweile ein modularer Aufbau and die Kombination von erprobten Baukastenkomponenten zu einer Anlage. Es gibt verschiedene Bauformen, von denen sich jede in Verbindung mit bestimmten Erzeugnissen and Bedingungen bewährt hat. In manchen Anwendungen mit kleinen Stückzahlen, zahlreichen Varianten oder bei einzelnen diffizilen Arbeitsschritten können Handarbeitsplätze erforderlich sein, was zu sog. hybriden Montagesystemen als Kombination von Hand- und Maschinenarbeitsplätzen führt.

  12. Methodik und Qualität statistischer Erhebungen

    NASA Astrophysics Data System (ADS)

    Krug, Walter; Schmidt, Jürgen; Wiegert, Rolf

    Kapitel 8 wirft einen Blick hinter die Kulissen statistischer Arbeit und ihrer Methoden, insbesondere auch hinter die der amtlichen Statistik: Wie kommen die Myriaden von Zahlen zustande, die heute aus statistischen Quellenwerken aller Art und aus Datenbanken abgerufen werden können? Dabei wird deutlich, welche Schwierigkeiten bei Erhebungen, insbesondere bei Stichprobenerhebungen, zu überwinden sind, wie man Antwortverweigerer kooperativer stimmt, wie sich auch aus kleinen Stichproben auf intelligente Weise verlässliche Ergebnisse erzielen lassen und wie Großstichproben auf europäischer Ebene harmonisiert werden. Am Beispiel des Zensus 2011 wird gezeigt, wie sich eine Kombination von Stichproben und Registerauswertungen als Ersatz für eine Volkszählung nutzen lässt. Mitglieder der Deutschen Statistischen Gesellschaft waren daran kooperativ beteiligt.

  13. Experimentalphysik 4

    NASA Astrophysics Data System (ADS)

    Demtröder, W.

    Kern-, Teilchen- und Astrophysik ist der vierte Band des auf vier Bände angelegten Lehrbuchs zur Experimentalphysik von Professor Demtröder. Die Lehrinhalte des vierten Semesters Physik werden nach dem Konzept der drei ersten Bände leicht verständlich und dabei möglichst quantitativ präsentiert. Wichtige Definitionen und Formeln sowie alle Abbildungen und Tabellen wurden zweifarbig gestaltet, um das Wesentliche deutlicher herauszustellen. Durchgerechnete Beispiele im Text sowie Übungsaufgaben nach den Kapiteln mit ausführlichen Lösungen am Ende des Buchs helfen dabei, den Stoff zu bewältigen, und regen zu eigener Mitarbeit an. Viele Illustrationen sowie einige Farbtafeln zu ausgesuchten Themen tragen zur Motivation bei und bringen Spaß bei der Arbeit mit diesem Buch.

  14. Campus Single Sign-On und hochschulübergreifendes Identity Management

    NASA Astrophysics Data System (ADS)

    Hommel, Wolfgang

    Das im Rahmen von IntegraTUM für die TUM geschaffene Identity & Access Management System setzt das Paradigma unified login um, d. h. ein Benutzer kann alle für ihn relevanten Dienste innerhalb der Hochschule mit derselben Loginname-/Passwortkombination nutzen. Dieser Artikel zeigt, wie auf Basis der Software Shibboleth und der deutschlandweiten Hochschulföderation DFN-AAI als weitere Mehrwerte das campusweite web single sign-on und die nahtlose Nutzung zahlreicher externer Web-Anwendungen erreicht werden. Als Beispiel für die Abläufe bei der Erschließung neuer Dienste für die hochschulübergreifende Nutzung wird die Anbindung von Learning Management Systemen auf Basis des DFN-AAI E-Learning-Profils diskutiert. Den umfassenden Vorteilen werden schließlich die aktuellen technischen Grenzen bei der Umsetzung des hochschulübergreifenden Identity Management gegenübergestellt.

  15. Die Amtliche Sammlung von Untersuchungsverfahren nach § 64 LFGB, § 35 Vorläufiges Tabakgesetz und § 28b Gentechnikgesetz - ein Instrument der amtlichen Lebensmittelüberwachung

    NASA Astrophysics Data System (ADS)

    Renger, Silke; Stachel, Carolin

    Immer wieder werden Skandale in Zusammenhang mit Lebensmitteln bekannt. Schlagworte wie BSE, Gammelfleisch, Acrylamid, Cumarin oder auch Melamin, Dioxin sind den Verbrauchern geläufig und erschüttern das Vertrauen in ein gesundes und ernährungsphysiologisch wertvolles Lebensmittel. Das Bewusstsein des Verbrauchers hinsichtlich der Ernährung und der Auswahl beim Kauf der Lebensmittel hat sich in den vergangenen Jahren deutlich verändert. Bei der Auswahl seiner Lebensmittel liegt sein Augenmerk verstärkt auf gesunden, qualitativ hochwertigen und vor allem sicheren Lebensmitteln. Dies wurde insbesondere bei dem verhaltenen Kauf von Fleisch und Fleischerzeugnissen während der BSE-Krise oder auch dem kürzlich aufgetretenen Gammelfleischskandal deutlich.

  16. Refined estimates of biogenic hydrocarbon emissions for Atlanta. Interim report, January 1992-November 1993

    SciTech Connect

    Pierce, T.E.; Coventry, D.H.; Van Meter, A.R.; Geron, C.D.

    1993-11-01

    Biogenic emissions of volatile organic compounds (VOCs) reportedly play an important role in ozone non-attainment for Atlanta. To better understand this problem, the Southern Oxidant Study participated in an intensive field experiment around Atlanta during the summer of 1992. This paper compares estimates from three different inventories. The first inventory uses the existing Biogenic Emissions Inventory System (BEIS) in the Urban Airshed Model (UAM). UAM-BEIS relies on county-aggregated land use patterns and emission factors dating back to the 1970's. A second inventory incorporates recent (circa 1990) satellite data. Information from the U.S. Forest Service (USFS) is used to increase the coverage of trees in urban areas from 20% to 30%. The third inventory uses USFS forest inventory statistics to compute leaf biomass and tree species composition for about 1 acre forest survey plots, which are extrapolated to about 2000 hectares forest areas as delineated by aerial photography.

  17. Stein-Schere-Papier

    NASA Astrophysics Data System (ADS)

    Springborn, Boris

    Wie gewinnt man im Spiel? Die Analyse von Strategien bei Gesellschaftsspielen ist ein Thema der mathematischen Spieltheorie. Mit ihren Methoden kann man aber nicht nur Spiele wie Schach oder Skat untersuchen, sondern auch verschiedenste Konfliktsituationen, bei denen das Schicksal jedes einzelnen Akteurs nicht nur vom eigenen Verhalten abhängt, sondern auch vom Verhalten der anderen, die ebenso wie er versuchen, ein für sie selbst möglichst positives Ergebnis herauszuschlagen. Die Spieltheorie hat großen Einfluss in den Wirtschaftswissenschaften. Auch in der Psychologie, Soziologie, Biologie und der Militärwissenschaft findet sie Anwendung. In der folgenden Aufgabe geht es aber tatsächlich um ein Spiel, und zwar um ein sehr einfaches, das jeder kennt. Trotzdem ist die Lösung nicht ganz einfach, und wer sie findet, hat schon die eine oder andere grundlegende Idee der Spieltheorie verstanden.

  18. Finanzierung des Studiums

    NASA Astrophysics Data System (ADS)

    Domnick, Ivonne

    "Das liebe Geld“ - ein Thema, das Sie durch das ganze Studium begleitet und auch in der Examensphase und bei der späteren Berufswahl eine entscheidende Rolle spielen wird. Naturwissenschaftler und Ingenieure haben auf dem Arbeitsmarkt sicher derzeit die Nase vorn und brauchen sich über ihre berufliche Zukunft nicht so große Gedanken machen. Doch vor der Karriere muss zunächst einmal eine sichere Studienfinanzierung auf die Beine gestellt werden.

  19. Historisches Rätsel Liebe, Revolution und Mathematik

    NASA Astrophysics Data System (ADS)

    Loos, Andreas

    2002-07-01

    In Jahr 1800 wies William Herschel bei der Untersuchung des Sonnenlichts erstmals Strahlung außerhalb des sichtbaren Spektrums nach. Sein Sohn Frederick entwickelte ein Gerät zur Vermessung der Sonnenintensität, das Aktinometer. Dieses Gerät wurde in einigen Messkampagnen verwendet, setzte sich aber letztlich nicht durch. Heute ist die Vermessung der Sonneneinstrahlung ein wesentlicher Bereich, der zur Modellierung solarer Energiegewinnungsanlagen erforderlich ist.

  20. Ultra-high, resolution, modular optical angle encoder for space-based opto-mechanical applications

    NASA Technical Reports Server (NTRS)

    Luther, Holger; Beard, Paul; Mitchell, Donald; Thorburn, William

    1995-01-01

    A 27-bit optical encoder using a novel patent pending technology has been developed by the MicroE Development Center of BEI Sensors & Systems Company and tested by the Sensor Systems Group (SSG) Inc., in a positioning and stabilization mirror assembly (PSMA) designed and constructed under a grant from the Marshall Space Flight Center. Test results verified performance within the specifications of the PSMA.

  1. Kamera-basierte Erkennung von Geschwindigkeitsbeschränkungen auf deutschen Straen

    NASA Astrophysics Data System (ADS)

    Nienhüser, Dennis; Ziegenmeyer, Marco; Gumpp, Thomas; Scholl, Kay-Ulrich; Zöllner, J. Marius; Dillmann, Rüdiger

    An Fahrerassistenzsysteme im industriellen Einsatz werden hohe Anforderungen bezüglich Zuverlässigkeit und Robustheit gestellt. In dieser Arbeit wird die Kombination robuster Verfahren wie der Hough-Transformation und Support-Vektor-Maschinen zu einem Gesamtsystem zur Erkennung von Geschwindigkeitsbeschränkungen beschrieben. Es setzt eine Farbvideokamera als Sensorik ein. Die Evaluation auf Testdaten bestätigt durch die ermittelte hohe Korrektklassifikationsrate bei gleichzeitig geringer Zahl Fehlalarme die Zuverlässigkeit des Systems.

  2. Elektronenmikroskopie an Alzheimer-Fibrillen

    PubMed Central

    Sachse, Carsten; Grigorieff, Nikolaus; Fändrich, Marcus

    2009-01-01

    Zusammenfassung Amyloidfibrillen sind fadenförmige Eiweißablagerungen, die im Gehirn von Alzheimerpatienten auftreten. Durch Verwendung verbesserter, computergestützter Verfahren zur Bearbeitung elektronenmikroskopischer Aufnahmen gelang es nun erstmals, bei Alzheimer-Amyloidfibrillen strukturelle Details mit einer Auflösung von unter 1 nm darzustellen. Langfristig könnten diese Methoden auch zu neuen medikamentösen Strategien führen. PMID:20126429

  3. Wasserkraftwerke

    NASA Astrophysics Data System (ADS)

    Zahoransky, Richard; Allelein, Hans-Josef; Bollin, Elmar; Oehler, Helmut; Schelling, Udo

    Die Wasserkraft ist global die bedeutendste erneuerbare Energiequelle. Sie hat in Deutschland einen stagnierenden Anteil von ca. 5 % der gesamten Stromerzeugung (Bild 1.2). In Deutschland wurde die Wasserkraft allerdings bei der Stromerzeugung durch die Windkraft und vor kurzem sogar von der Biomassevergasung überholt. Die Wasserkraft ist andererseits eine gut berechenbare Energiequelle und unterliegt nicht den nur kurzfristig vorhersehbaren Schwankungen der Wind- und Solarenergien.

  4. Physik gestern und heute Von der Metallstange zum Hochenergielaser

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2002-05-01

    Im Mai 1752 wurde in Marly bei Paris auf Anregung des amerikanischen Forschers und Politikers Benjamin Franklin erstmals die elektrische Natur des Blitzes nachgewiesen. Damals beschrieb Franklin auch eine technische Vorrichtung, die als Schutz von Gebäuden vor Blitzschlägen dienen sollte: den Blitzableiter. Diese aus heutiger Sicht scheinbar triviale Vorrichtung wurde aber keineswegs unmittelbar akzeptiert. Und bis heute ist die Forschung zum Schutz von Einrichtungen vor Blitzschlägen nicht abgeschlossen.

  5. The X-ray view of EROs

    NASA Astrophysics Data System (ADS)

    Brusa, M.; Comastri, A.; Daddi, E.; Cimatti, A.; Vignali, C.

    (1) Dip. Astronomia Bologna University, via Ranzani 1, I-40127 Bologna ITALY (2) INAF - Osservatorio Astronomico di Bologna, via Ranzani 1, I-40127 Bologna ITALY (3) ESO - European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei Muenchen Germany (4) INAF - Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-55025 Firenze, Italy (5) Dept. of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802, USA

  6. Der II. Hauptsatz der Wärmelehre

    NASA Astrophysics Data System (ADS)

    Heintze, Joachim

    Wir haben in (4.44) den II. Hauptsatz als empirische Tatsache folgendermaßen formuliert: (i) Wärmeenergie geht von selbst nur von einem wärmeren Körper auf einen kälteren über, niemals in der umgekehrten Richtung. Nun werden wir beweisen, dass sich aus diesem Prinzip folgende äquivalente Formulierungen für den II. Hauptsatz ableiten lassen: (ii) Es ist unmöglich, ein Perpetuum mobile zweiter Art zu bauen, d. h. eine Maschine, die fortlaufend Wärmeenergie vollständig in mechanische Arbeit umsetzen kann. Eine Wärmekraftmaschine, die einen Kreisprozess mit der höchsten Temperatur Tw und der niedrigsten Temperatur Tk durchläuft, hat höchstens den Carnotschen Wirkungsgrad c = (Tw - Tk)/Tw. Wenn in der Maschine nur reversible Prozesse ablaufen, die gesamte Wärmezufuhr bei der Temperatur Tw erfolgt und ausschließlich bei der Temperatur Tw gekühlt wird, ist ihr Wirkungsgrad = C. Es gibt keine Wärmekraftmaschine, die eine bessere Ausnutzung der Wärmeenergie ermöglicht. (iv) In jedem thermodynamischen System existiert die Zustandsgröße Entropie, definiert durch ihr Differential dS = (dQrev)/T . Entropie kann erzeugt, aber nicht vernichtet werden. Bei Zustandsänderungen, die in einem abgeschlossenen System ablaufen, nimmt die Entropie entweder zu (irreversible Prozesse), oder sie bleibt konstant (reversible Prozesse). Im Anschluss an (iii) werden wir zur Definition der thermodynamischen Temperatur und bei der Diskussion von (iv) zu einem tieferen Verständnis der Entropie gelangen. Es zeigt sich, dass die Entropie das eigentliche Bindeglied zwischen Mechanik und Wärmelehre darstellt. Am Ende des Kapitels werden wir einige Anwendungen des II. Hauptsatzes betrachten.

  7. Ist da jemand? Wie Außerirdische uns entdecken können

    NASA Astrophysics Data System (ADS)

    Heller, R.

    2016-06-01

    Astronomen schlagen vor, sich bei der Suche nach Signalen außerirdischer Zivilisationen auf einen schmalen Bereich am Himmel zu konzentrieren. Von Planeten um Sterne, die in diesem Streifen liegen, würde sich die Erde vergleichsweise leicht entdecken lassen. Sollte es dort intelligentes Leben geben, könnte uns dieses schon längst aufgespürt und eine Botschaft Richtung Erde geschickt haben.

  8. Stationäre Motorvermessung mit verschiedenen Methoden und Modellen

    NASA Astrophysics Data System (ADS)

    Kötter, Hinrich; Sequenz, Heiko

    Die kontinuierliche Verschärfung der gesetzlichen Vorgaben bezüglich Emissionen stellt die Motorenentwickler vor neue Herausforderungen (Bild 6-1, [1, 2]). Gleichzeitig ist zu erwarten, dass sich der langfristige Trend der letzten Jahren bei den Kraftstoffpreisen [3] trotz kurzzeitiger Schwankungen fortsetzen wird (Bild 6-1 rechts, Jahresmittelwerte). Auf die steigenden Kraftstoffpreise sowie die Verpflichtungen bezüglich der CO2- Emissionswerte kann dauerhaft nur mit Kraftstoff sparenden Motoren reagiert werden.

  9. A Sodium-Containing Quasicrystal: Using Gold To Enhance Sodium's Covalency in Intermetallic Compounds

    SciTech Connect

    Smetana, Volodymyr; Lin, Qisheng; Pratt, Daniel K.; Kreyssig, Andreas; Ramazanoglu, Mehmet; Corbett, John D.; Goldman, Alan I.; Miller, Gordon J.

    2013-09-26

    Gold macht stabil: Na13Au12Ga15, ein natriumhaltiges thermodynamisch stabiles quasikristallines Material, wurde bei einer systematischen Studie des polaren Na-Au-Ga-Intermetallsystems entdeckt. Sein Elektron/Atom-Verhältnis von 1.75 ist für Bergman-Ikosaederphasen extrem klein, doch der substanzielle Au-Anteil sorgt für eine Hume-Rothery-Stabilisierung und neuartige polar-kovalente Na-Au-Wechselwirkungen.

  10. Preliminary study on near-infrared spectroscopic measurement of urine hippuric acid for the screening of biological exposure index

    NASA Astrophysics Data System (ADS)

    Ogawa, Mitsuhiro; Yamakoshi, Yasuhiro; Motoi, Kosuke; Yamakoshi, Takehiro; Yamakoshi, Ken-Ichi

    2008-10-01

    Biological Exposure Indices (BEIs) are reference for a chemical or its metabolite in the biological specimen. BEIs give guidelines for the evaluation of potential health hazards or for diagnosis of occupational illnesses. Among them, urine hippuric acid (HA) that is a metabolites of toluene is considered as the BEIs of toluene exposure for human and measured from workers using toluene. In this study, we attempted to develop a brief measurement of urine HA by using near-infrared spectroscopy. As the first step, water solutions of hippuric acid of several concentrations (0-250mg/dl) are measured. Afterward, artificial urines conditioned by adding glucose and urine to HA solutions were measured and analyzed. The solvents are optically measured within near infrared region (750-2500nm) obtaining optical absorption. Then, differential absorbance were calculated by subtraction of analyte absorbance from ion-exchange water absorbance and analyzed. As a result, for HA solutions, a calibration equation from absorbance in two wavelengths can be obtained by using multiple regression (R2=0.935). However, this calibration cannot provide a good estimation for artificial urines. Secondary, another calibration from three wavelengths was obtained and providing a good regression (R2=0.934). This result suggests that a brief urine constituents measurement using near-infrared spectroscopy can be developed.