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Sample records for nierenarterienstenose technische ergebnisse

  1. Einführung in die Technische Chemie

    NASA Astrophysics Data System (ADS)

    Behr, Arno; Agar, David W.; Jörissen, Jakob

    Die "Technische Chemie" ist ein Lehrfach an Universitäten und Hochschulen. Nach dem die Studierenden der Chemie in den ersten Semestern ihres Studiums ausrei chen de theoretische Kenntnisse in Allgemeiner, Anorganischer, Organischer und Physikalischer Chemie erlangt haben, soll die Technische Chemie einen Blick auf die praktische Anwendung dieser Naturwissenschaft in unserer Wirtschaft lenken. Es gibt keine "biologische Industrie", "physikalische Industrie" oder "mathematische Industrie", wohl aber seit über 150 Jahren eine "chemische Industrie", die in dieser lan gen Zeit zahlreiche chemische Prozesse entwickelt und dazu vielfältige Methoden erarbeitet hat. Das Lehrfach Technische Chemie gibt einen Überblick über diese Pro zesse und Methoden und erleichtert dadurch den Schritt von der Universität zur be ruflichen Praxis.

  2. Scramjet Research Activities at the Institute of Flight Propulsion of the Technische Universitaet Muenchen

    NASA Astrophysics Data System (ADS)

    Maier, D.; Kirstein, S.; Fuhrmann, T.; Rocci Denis, S.; Hupfer, A.; Kau, H.-P.

    2009-01-01

    At the Institute of Flight Propulsion (LFA) of the Technische Universitaet Muenchen scramjet research has been carried on since the 70's. Based on the experiences gained during the last decades experimental and numerical studies on scramjet engines are currently conducted within a research training group (GRK1095) funded by the German Research Foundation (DFG). The main goal of this program is to design a fixed geometry scramjet engine for a Mach 8 flight at an operating altitude of 30 km. In addition to a historical overview latest research results are presented in this paper.

  3. 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.“

  4. Photogrammetry and Remote Sensing in the MSc Program "ESPACE" at Technische Universitaet Muenchen

    NASA Astrophysics Data System (ADS)

    Stilla, U.; Iwaszczuk, D.; Pail, R.

    2014-04-01

    ESPACE is an interdisciplinary Master's study programme of Technische Universitaet Muenchen (TUM) positioned at the interface between space technology and the engineering and natural science-based use of satellite data. It combines the technical aspects of the satellite and observation systems with scientific and commercial applications. A core topic beside space engineering and satellite applications engineering is satellite and remote sensing data analysis. This paper explains the background and goals of the Masters's study programme, addresses the target groups and qualification profile, and gives an overview about the specialization fields. The special role of Photogrammetry and Remote Sensing is further explained in this context. The structure and embedding of international alliances by a double degree program with Wuhan University is shown.

  5. Optical dimensional metrology at Physikalisch-Technische Bundesanstalt (PTB) on deep sub-wavelength nanostructured surfaces

    NASA Astrophysics Data System (ADS)

    Bodermann, B.; Ehret, G.; Endres, J.; Wurm, M.

    2016-06-01

    The dark-field microscopy method with alternating grazing incidence UV illumination (UV-AGID) developed at Physikalisch-Technische Bundesanstalt offers the possibility of measuring individual isolated line structures with linewidths down to the sub-wavelength regime. In contrast, scatterometry is able and already widely used to measure average dimensional parameters of periodic structures down to the deep sub-wavelength regime. Both methods can be used for dimensional measurements of micro- and nanostructures, in particular the critical dimensions (CDs) on wafers or photomasks in the semiconductor industry, complementing each other favourably. Based on numerical simulations, we have investigated the ultimate limits of these two methods in the deep sub-wavelength regime. It has been shown that AGID microscopy in the DUV spectral range is in principle capable of measuring line structures with CDs down to a few 10 nm, depending on the structure material. For scatterometry, no fundamental limit has been observed. In practice, a technical limit due to the limited signal-to-noise ratio is expected for CDs of a few nm in width.

  6. Comparative study of beta-decay data for eight nuclides measured at the Physikalisch-Technische Bundesanstalt

    NASA Astrophysics Data System (ADS)

    Sturrock, P. A.; Fischbach, E.; Javorsek, D.; Jenkins, J. H.; Lee, R. H.; Nistor, J.; Scargle, J. D.

    2014-07-01

    We present the results of time-series analyses of data, kindly provided by the Physikalisch-Technische Bundesanstalt, concerning the beta-decays of Ag108, Ba133, Cs137, Eu152, Eu154, Kr85, Ra226, and Sr90. From measurements of the detector currents, we find evidence of annual oscillations (especially for Ra226), and for several solar r-mode oscillations. It is notable that the frequencies of these r-mode oscillations correspond to exactly the same sidereal rotation rate (12.08 year-1) that we have previously identified in r-mode oscillations detected in both Mt Wilson solar diameter data and Lomonosov Moscow State University Sr90 beta-decay data. Ba133 is found to be anomalous in that current measurements for this nuclide have a much larger variation (by 4 σ) than those of the other nuclides. It is interesting that analysis of variability measurements in the PTB files yields strong evidence for an oscillation for Ba133 but only weak evidence for Ra226.

  7. The source-sample stage of the new two-dimensional angular correlation of annihilation radiation spectrometer at Technische Universität München

    NASA Astrophysics Data System (ADS)

    Ceeh, Hubert; Weber, Josef Andreas; Leitner, Michael; Böni, Peter; Hugenschmidt, Christoph

    2013-04-01

    Angular correlation of annihilation radiation (ACAR) is a well established technique for the investigation of the electronic structure. A major limitation of ACAR studies is the available positron flux at a small spot on the sample. For this reason, the focus of this work is put on the discussion of a newly developed source-sample stage of the new 2D-ACAR spectrometer at Technische Universität München which uses an optimized static magnetic field configuration to guide the positrons onto the sample. The achieved spot diameter is dFWHM = 5.4 mm, with a high efficiency over the whole energy spectrum of the 22Na positron source. The implications of the performance of the source-sample stage are discussed with regard to 2D-ACAR measurements of single crystalline α-quartz, which serves as a model system for the determination of the total resolution. A value of (1.53 × 1.64) mrad2 FWHM was achieved at room temperature.

  8. The source-sample stage of the new two-dimensional angular correlation of annihilation radiation spectrometer at Technische Universitaet Muenchen

    SciTech Connect

    Ceeh, Hubert; Weber, Josef Andreas; Boeni, Peter; Leitner, Michael; Hugenschmidt, Christoph

    2013-04-15

    Angular correlation of annihilation radiation (ACAR) is a well established technique for the investigation of the electronic structure. A major limitation of ACAR studies is the available positron flux at a small spot on the sample. For this reason, the focus of this work is put on the discussion of a newly developed source-sample stage of the new 2D-ACAR spectrometer at Technische Universitaet Muenchen which uses an optimized static magnetic field configuration to guide the positrons onto the sample. The achieved spot diameter is d{sub FWHM}= 5.4 mm, with a high efficiency over the whole energy spectrum of the {sup 22}Na positron source. The implications of the performance of the source-sample stage are discussed with regard to 2D-ACAR measurements of single crystalline {alpha}-quartz, which serves as a model system for the determination of the total resolution. A value of (1.53 Multiplication-Sign 1.64) mrad{sup 2} FWHM was achieved at room temperature.

  9. Analysis of beta-decay rates for Ag 108, Ba 133, Eu 152, Eu 154, Kr 85, Ra 226, and Sr 90, measured at the Physikalisch-Technische Bundesanstalt from 1990 to 1996

    SciTech Connect

    Sturrock, P. A.; Fischbach, E.; Jenkins, J.

    2014-10-10

    We present the results of an analysis of measurements of the beta-decay rates of Ag 108, Ba 133, Eu 152, Eu 154, Kr 85, Ra 226, and Sr 90 acquired at the Physikalisch-Technische Bundesanstalt from 1990 through 1995. Although the decay rates vary over a range of 165 to 1 and the measured detector current varies over a range of 19 to 1, the detrended and normalized count rate measurements exhibit a sinusoidal annual variation with amplitude in the small range 0.068%-0.088% (mean 0.081%, standard deviation 0.0072%, a rejection of the zero-amplitude hypothesis) and phase-of-maximum in the small range 0.062-0.083 (January 23 to January 30). In comparing these results with those of other related experiments that yield different results, it may be significant that this experiment, at a standards laboratory, seems to be unique in using a 4π detector. These results are compatible with a solar influence, and do not appear to be compatible with an experimental or environmental influence. It is possible that Ba 133 measurements are also subject to a non-solar (possibly cosmic) influence.

  10. Technische Systeme für den Herzersatz und die Herzunterstützung

    NASA Astrophysics Data System (ADS)

    Schöb, Reto; Loree, Howard M.

    Herzkrankheiten verursachen allein in den Vereinigten Staaten jährlich mehr als 700’000 Todesfälle. Ungefähr 3 Millionen Patienten in den U.S.A. leiden gemäss der American Heart Association (AHA) und dem National Heart, Lung and Blood Institute (NHLBI) an kongestivem Herzversagen (Congestive Heart Failure, CHF), welches eine chronische, sehr entkräftende und degenerative Krankheit ist: Das Herz ist dabei unfähig, hinreichend Blut zu den Organen des Körpers zu pumpen. Über 400’000 Fälle von CHF werden jedes Jahr diagnostiziert. Ähnliche Zahlen werden für Europa und Japan zusammen geschätzt. Basierend auf Daten vom AHA und NHLBI beträgt die fünfjährige Überlebensrate für CHF-Patienten lediglich etwa 50% [1]. 70’000-120’000 dieser Patienten könnten von einer Herzverpflanzung profitieren. 1999 wurden in den USA aber nur 2185 Herztransplantationen durchgeführt während die Warteliste über 4000 Patienten beträgt [2]. Ein akuter Mangel an Spenderherzen und die enormen Kosten (250’000-400’000 USD pro Patient) sind die begrenzenden Faktoren für Herztransplantationen [3]. Dies bedeutet, dass eine riesige Anzahl von Patienten durch ein zuverlässiges und verschleissfreies, nichtthrombotisches, total implantierbares, künstliches Herz gerettet werden könnten. Bis heute jedoch kein derartiges Implantat kommerziell verfügbar.

  11. The Technische Universitat Hamburg-Harburg and the Elbe Bay Area.

    ERIC Educational Resources Information Center

    Danielmeyer, H. G.

    1984-01-01

    The establishment of the Technical University of Hamburg-Harburg is unique in that its justification was based less on educational need than on the need to enhance research and technology transfer capacity. The university's structure is also unconventional in Germany, and considerable emphasis is placed on collaboration with industry. (Author/MSE)

  12. Zweiwegintegration durch zweisprachige Bildung? Ergebnisse aus der Staatlichen Europa-Schule Berlin

    NASA Astrophysics Data System (ADS)

    Meier, Gabriela

    2012-06-01

    While there is no simple recipe of how to respond to the multitude of languages present in many European schools, this article presents a promising alternative to monolingual education. The focus is on Staatliche Europa-Schule Berlin (SESB), a two-way immersion (TWI) model that unites children whose mother tongue is German with children whose mother tongue is another locally spoken language in one class and teaches them together in two languages. Thus in this model, offered by 17 primary schools and 13 secondary schools in Berlin, pupils learn in two languages from and with each other. Based on a largely quantitative, quasi-experimental study with 603 students, evidence is provided that there are a number of peace-linguistic benefits that can promote two-way social integration, besides fostering personal and societal multilingualism. This suggests that TWI education as practised in Berlin could serve as an educational model for other multilingual parts of Europe.

  13. Procedures for Computing Transonic Flows for Control of Adaptive Wind Tunnels. Ph.D. Thesis - Technische Univ., Berlin, Mar. 1986

    NASA Technical Reports Server (NTRS)

    Rebstock, Rainer

    1987-01-01

    Numerical methods are developed for control of three dimensional adaptive test sections. The physical properties of the design problem occurring in the external field computation are analyzed, and a design procedure suited for solution of the problem is worked out. To do this, the desired wall shape is determined by stepwise modification of an initial contour. The necessary changes in geometry are determined with the aid of a panel procedure, or, with incident flow near the sonic range, with a transonic small perturbation (TSP) procedure. The designed wall shape, together with the wall deflections set during the tunnel run, are the input to a newly derived one-step formula which immediately yields the adapted wall contour. This is particularly important since the classical iterative adaptation scheme is shown to converge poorly for 3D flows. Experimental results obtained in the adaptive test section with eight flexible walls are presented to demonstrate the potential of the procedure. Finally, a method is described to minimize wall interference in 3D flows by adapting only the top and bottom wind tunnel walls.

  14. Gesellschaft fuer angewandte Mathematik und Mechanik, Scientific Annual Meeting, Technische Universitaet Wien, Vienna, Austria, Apr. 5-9, 1988, Reports

    NASA Astrophysics Data System (ADS)

    Various papers on applied mathematics and mechanics are presented. The general topics considered include: numerical treatment of implicit differential equations and differential algebraic systems; software for scientific calculation; structural analysis and simulation; stochastic methods; biomathematics; interpolation and approximation; quadrature; optimization; methods in operations research; enclosures for linear and nonlinear equations; enclosures for functional equations; ordinary differential equations and dynamical systems; ordinary differential and difference equations; and numerics of stiff differential equations. Also addressed are: waves, analysis, applications, and numerics in partial differential equations; large systems of linear equations; multigrid methods; iterative processes in applied function theory; discrete mathematics and informatics; fundamentals, special methods, and shells in FEM; beams and special applications; fundamentals, solid mechanics, and fluid mechanics in BEM.

  15. Clearance flow-generated transverse forces at the rotors of thermal turbomachines. Ph.D. Thesis - Technische Univ., 1975

    NASA Technical Reports Server (NTRS)

    Urlichs, K.

    1983-01-01

    Self-excited rotor whirl represents a serious hazard in the operation of turbomachines. The reported investigation has, therefore, the objective to measure the lateral forces acting on the rotor and to determine the characteristic pressure distribution in the rotor clearance area. A description is presented of an approach for calculating the leakage flow in the case of an eccentric rotor position on the basis of empirical loss coefficients. The results are reported of an experimental investigation with a turbine stage, taking into account a variation of the clearance characteristics. The pressure data measured are consistent with the theoretical considerations.

  16. Integriertes Informationsmanagement am KIT Was bleibt? Was kommt?

    NASA Astrophysics Data System (ADS)

    Labitzke, Sebastian; Nussbaumer, Martin; Hartenstein, Hannes; Juling, Wilfried

    Der Beitrag beschreibt wesentliche seit dem Jahr 2005 an der Universität Karlsruhe bzw. am Karlsruher Institut für Technologie erzielte Ergebnisse in Bezug auf technische und organisatorische Integration für das Informationsmanagement. Insbesondere stehen die Portaldienste und das Identitätsmanagement im Fokus der technischen Innovation. Daneben werden zwei organisatorische Innovationen vorgestellt, die sich dediziert Fragestellungen zur IT-Governance und IT-Compliance widmen. Abschließend werden erzielte Schlüsselerfahrungen diskutiert, die im Zuge des Aufbaus eines integrierten Informationsmanagements gemacht wurden. Ausblickend wollen wir einen Bezug zu den allgegenwärtigen Problemstellungen und verbundenen Herausforderungen derartiger Vorhaben aufzeigen - Herausforderungen, die waren, sind und bleiben werden.

  17. Gymnasien in Thuringen und Bayern. Ergebnisse einer vergleichenden Untersuchung ("Gymnasien" in Thuringia and in Bavaria: Results of a Comparative Study).

    ERIC Educational Resources Information Center

    Bottcher, Ilona; Weishaupt, Horst

    1999-01-01

    Uses both qualitative and quantitative procedures to study select "Gymnasien" in Thuringia and Bavaria. Explores the influence the Gymnasium has had on individual schools' developments. Examines how "long-term mental formations" determine the transformation process. Examines differences between the school structures of Gymnasien in East and West…

  18. Untersuchung ausgewählter Oberflächen-, Grund- und Bodenwasserproben auf Perchlorat in Deutschland: Erste Ergebnisse

    NASA Astrophysics Data System (ADS)

    Scheytt, Traugott J.; Freywald, Jessika; Ptacek, Carol J.

    2011-03-01

    Perchlorate is a component found in solid rocket fuels, explosives, fireworks, and road flares. In addition, perchlorate is a minor component of natural salt deposits in semiarid and arid regions. Discharge and storage areas as well as accidents are potential sources for perchlorate contamination of aquatic systems. Perchlorate has been detected in surface water and groundwater from several places worldwide. The aim of this study is to evaluate whether perchlorate occurs in surface water, groundwater, or soil leachate at selected sites in Germany. These sites include surface water from a military base in southern Germany, groundwater from a production site, and groundwater and soil leachate from a location where fireworks shows are performed regularly. Results show that perchlorate was detected in all surface water and groundwater samples with values around 1 μg/l. Highest values (up to 15,000 μg/l) were detected in pore waters of the "Maifeld" area in Berlin where soil was sampled immediately after a fireworks show.

  19. Ozeane: Ergebnisse der 7. Sitzung der Kommission für nachhaltige Entwicklung (CSD) der Vereinten Nationen

    NASA Astrophysics Data System (ADS)

    Schlimm, Jutta; Stietzel, Hans-Joachim

    1999-12-01

    The 7th session of the United Nations Commission on Sustainable Development (CSD) was organised from 19 30 April in the UN Headquarters in New York. The Commission on Sustainable Development was established in 1992 with the aim to implement the comprehensive action programme of Agenda 21. The topics on the agenda of this year’s CSD session included: oceans, tourism as well as consumption and production patterms with a special focus on the oceans item. The 7th Session covered two weeks. It began with the so-called “High Level Segment” during the first week when 89 ministers and high-ranking government representatives stated their points of view on various themes-sometimes also in interaction with the chairman. Concerning the topic of oceans CSD 7 focussed on a few main items of special priority for the implementation of the Agenda 21, both during the preparatory “Intersessional Working Group” and in the final document. These main items are: the conservation and integrated as well as sustainable management of fisheries and marine resources, including the ecosystem of the oceans, the prevention of pollution and degradation of the marine environment through land-based and other acticities, the improvement of the scientific knowledge on oceans and the interaction between the oceans and the global climate system. The decisions of CSD 7 adressed detailed and for the major part concrete proposals for action, appeals or requests to the international organisations and the interntional community with regard to these main items. Summarizing the 7th session, it can be said that in the oceans sector CSD 7 was quite successful in fullilling the task to study the implementation of Agenda 21, to set priorities and to address actors and the necessary actions.

  20. Comment on “Comparative study of beta-decay data for eight nuclides measured at the Physikalisch-Technische Bundesanstalt” [Astropart. Phys. 59 (2014) 47-58

    NASA Astrophysics Data System (ADS)

    Nähle, Ole; Kossert, Karsten

    2015-06-01

    We would like to comment on a recent paper by Sturrock et al. (2014) in which the authors analyze decay data acquired by an ionization chamber in our institute. They interpret the variations in the data as solar-driven changes in the decay rates of the radionuclides under study. In brief we would like to discuss and elucidate the properties and the origin of the data used by the authors and explain why these data are not a sound basis for claiming evidence for new physics.

  1. Research on oxidation by air and tempering of Raney nickel electrocatalysts for the H2 anodes of alkali combustion materials cells. Thesis - Braunschweig Technische Univ., 1982

    NASA Technical Reports Server (NTRS)

    Selbach, H. J.

    1984-01-01

    The controlled oxidation in air of Raney nickel electrocatalysts was studied, with special attention paid to the quantitative analysis of nickel hydroxide. The content of the latter was determined through X-ray studies, thermogravimetric measurements, and spectral photometric examinations. The dependence of the content on the drying of activated catalyst is determined. The influence of nickel hydroxide on the electrochemical parameters of the catalyst, such as diffusion polarization, is studied, including a measurement of the exchange current density using the potential drop method. Conservation by oxidation in air with ancillary stabilization of the oxide in an H2 flow at 300 C is explored, including reduction by H2, the influence of tempering time, and structural studies on conserved and stabilized catalyst, long term research on the catalyst, including the influence of aging on the reduced catalyst, and the results of impedance measurements are presented.

  2. Wie grün wünscht sich die Bevölkerung Deutschlands ihre Städte?. Ergebnisse der Naturbewusstseinsstudie 2015

    NASA Astrophysics Data System (ADS)

    Ströher, Helena; Mues, Andreas Wilhelm

    2016-06-01

    Green areas are of high importance for the population in Germany. This is demonstrated by the representative outcomes of the latest Awareness-of-Nature survey for 2015. Most interviewees do not only value urban greens as personally important but also state that they perceive them as crucial for society and environment. The article focuses especially on the perception by people from different age groups and levels of education. It highlights that the strong awareness of the population provides a good fundament for the objectives and strategies of social, environmental and nature conservation policies.

  3. Wie grün wünscht sich die Bevölkerung Deutschlands ihre Städte? - Ergebnisse der Naturbewusstseinsstudie 2015

    NASA Astrophysics Data System (ADS)

    Ströher, Helena; Mues, Andreas Wilhelm

    2016-05-01

    Green areas are of high importance for the population in Germany. This is demonstrated by the representative outcomes of the latest Awareness-of-Nature survey for 2015. Most interviewees do not only value urban greens as personally important but also state that they perceive them as crucial for society and environment. The article focuses especially on the perception by people from different age groups and levels of education. It highlights that the strong awareness of the population provides a good fundament for the objectives and strategies of social, environmental and nature conservation policies.

  4. Transitional Boundary Layers Under the Influence of High Free Stream Turbulence, Intensive Wall Cooling and High Pressure Gradients in Hot Gas Circulation. Ph.D. Thesis - Technische Hochschule, Karlsruhe, 1985

    NASA Technical Reports Server (NTRS)

    Rued, Klaus

    1987-01-01

    The requirements for fundamental experimental studies of the influence of free stream turbulence, pressure gradients and wall cooling are discussed. Under turbine-like free stream conditions, comprehensive tests of transitional boundary layers with laminar, reversing and turbulent flow increments were performed to decouple the effects of the parameters and to determine the effects during mutual interaction.

  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. Ergebnisse einer Lehrerbefragung zum Hintergrund des Englischunterrichts in der Hauptschuloberstufe (Results of a Teacher Questionnaire on the Background of Instruction in English in the Upper Grades of the Hauptschule [9-grade "terminal" school]).

    ERIC Educational Resources Information Center

    Hellwig, Karlheinz

    1980-01-01

    The questionnaire dealt with: earmarks of weaker students, parents' attitude, the teachers' training and working conditions, problems of individual instruction, time-frame, existence of professional associations, evaluation of professional conferences, and the use of media. Some evaluations are appended. (IFS/WGA)

  7. Welche Kompetenzen brauchen betriebliche Weiterbildner in Zukunft? Ergebnisse einer Delphi-Studie in einem Industrieunternehmen (Qualifications Needed by Educational Staff Working in the Field of Further Education in the Industrial Sector--Results of a Delphi-study Carried out in an Industrial Enterprise).

    ERIC Educational Resources Information Center

    Harteis, Christian; Prenzel, Manfred

    1998-01-01

    Attempts to reveal the qualifications that will become important, due to technological change and growing internationalization of competition, for trainers (educational staff) in industrial enterprises. Indicates that the results lead to a view of further education within firms as a service that is subject to competition on the open market. (CMK)

  8. Pumpspeicherbecken im Karstgrundwasserleiter des Weißen Jura der Schwäbischen Alb. Erste Ergebnisse aus der geologischen und hydrogeologischen Erkundung für die Planfeststellung Pumped-storage hydroelectric power plant in the Jurassic karst aquifer of the swabian alb, Germany

    NASA Astrophysics Data System (ADS)

    Neukum, Christoph; Köhler, Hans Joachim; Fernandez-Steeger, Tomas; Hennings, Sibylle; Azzam, Rafig

    2014-06-01

    Extensive geological and hydrogeological investigations have been undertaken for the planned pumped-storage hydroelectric power plant in "Blautal" (Swabian Alb, Germany) in order to characterise the Jurassic karst aquifer in which the lower reservoir will be constructed. The preferred option for the plant setup is to integrate the lower reservoir into the groundwater without sealing. Therefore, in order to reliably predict the impact of the pumped storage plant operations on the surrounding drinking water wells and groundwater dependent ecosystems, a comprehensive database has been developed to assess the hydraulic conditions of the karst aquifer. A large scale geological site investigation was carried out to characterise the rock mass and extensive hydraulic tests were performed in many boreholes. The results of the hydraulic characterisation were then implemented in a three dimensional flow model. In this paper, the first results of the geological and hydrogeological investigations are presented and discussed.

  9. Generation of inflow data for inhomogeneous turbulence

    NASA Astrophysics Data System (ADS)

    Johansson, Peter S.; Andersson, Helge I.

    2004-11-01

    Inflow boundary conditions for turbulent plane channel flow are generated by solving evolution equations only for the most energetic eddies. The dynamical systems are derived by Galerkin projecting the Navier-Stokes equations onto the subspaces spanned by various sets of the most energetic modes from a proper orthogonal decomposition (POD) of the same flow. Low-energy small-scale POD-modes are added randomly in order to impose some energy in the high wave number range. This is found to be crucial in order to more rapidly establish the correct level of dissipation and achieve a more realistic distribution of energy between the velocity components. The method is tested on a DNS of R*=180 and a LES of R*=400. Statistics such as mean velocity, rms-profiles, turbulent shear-stress and energy spectra become close to the fully developed state within 1500 wall units downstream the inlet.

  10. Factors Affecting the Outcomes of Carpal Tunnel Surgery: A Review.

    PubMed

    Zyluk-Gadowska, P; Zyluk, A

    2016-08-01

    Ziel der vorliegenden Arbeit war es, unter Berücksichtigung der in Pubmed und Medline veröffentlichten Ergebnisse nach Eingriffen am Karpalkanal zu ermitteln, inwieweit ausgewählte Faktoren wie das Patientenalter, die Dauer der Symptome, die Ausprägung der klinischen und elektrophysiologischen Befunde, das Vorliegen von Begleiterkrankungen und medikolegale Momente die Ergebnisse beeinflussen. Letztlich konnte für keinen der zahlreichen untersuchten Faktoren ein signifikanter Einfluss auf das Langzeitergebnis nachgewiesen werden. Bestehen die Beschwerden länger, sind die klinischen und elektrophysiologischen Befunde ausgeprägter und liegen Begleiterkrankungen vor, so fallen die Ergebnisse weniger gut aus, was darauf hindeutet, dass die betroffenen Patienten etwas weniger von der Operation profitieren. Nur bei Vorliegen von medikolegalen Faktoren wie Rechtsstreit oder Schadenersatzansprüchen lässt sich definitiv ein schlechtes Ergebnis voraussagen. PMID:27580438

  11. Empowering Indigenous Languages and Cultures: The Impact of German Bilateral Assistance in Latin America

    ERIC Educational Resources Information Center

    Cortina, Regina

    2010-01-01

    Working in Latin America for several decades to address the educational needs of poor and indigenous groups, the GTZ (Gesellschaft fur Technische Zusammenarbeit) has helped to develop the knowledge base of intercultural bilingual education. The goal of this article is to analyze Germany's impact from the mid-1970s to the present as the GTZ has…

  12. Physik gestern und heute: Visualisierung mit der Schlierenmethode

    NASA Astrophysics Data System (ADS)

    Heering, Peter

    2006-07-01

    Der Name des österreichischen Forschers Ernst Mach ist heute noch mit der Schallgeschwindigkeit verbunden. Diese Auszeichnung resultiert aus Machs Untersuchungen, wie sich Projektile mit Überschallgeschwindigkeit durch die Luft bewegen. Gerade in jüngster Zeit hat die Anwendung derartiger Methoden durch technische Modifikationen wieder einen Aufschwung erfahren.

  13. The Technical Information Library: TIB

    NASA Technical Reports Server (NTRS)

    Rosemann, Uwe

    1994-01-01

    The Technische Informationsbibliothek Hannover (TIB) is the German national central library for all areas of technology and related sciences, especially chemistry, computer science, mathematics, and physics. The TIB acquires and makes available a comprehensive collection of conventional and non-conventional literature, especially foreign material, with particular emphasis on specialized new publications which are difficult to obtain or in difficult languages.

  14. A Course on Reconfigurable Processors

    ERIC Educational Resources Information Center

    Shoufan, Abdulhadi; Huss, Sorin A.

    2010-01-01

    Reconfigurable computing is an established field in computer science. Teaching this field to computer science students demands special attention due to limited student experience in electronics and digital system design. This article presents a compact course on reconfigurable processors, which was offered at the Technische Universitat Darmstadt,…

  15. Completion of the Polo model coil

    SciTech Connect

    Bourquard, A.; Plat, X.; Bonnet, P.; Semal, D.; Personeni, G.; Bernaudat, M.; Hacquard, A.; Salvador, R.; Dombrowski, D.

    1996-07-01

    A superconducting poloidal field model coil as needed for tokamaks has been constructed by GEC Alsthom within the Polo project in effective collaboration with Forschungszentrum Karlsruhe, Institut fuer Technische Physik, Germany. The manufacturing procedures for the coil and its terminals are described.

  16. Educating Educators in a Volatile Climate--The Challenge of Modernising Higher Business Schools in Serbia and Montenegro

    ERIC Educational Resources Information Center

    Hollinshead, Graham

    2006-01-01

    This study is set in the rapidly changing higher educational environment that has ensued in Serbia and Montenegro in the post Milosevic era. Its primary focus is a "Training Trainers" initiative, mounted by the GTZ (Deutsche Gesellschaft fur Technische Zusammenarbeit/Society for Technical Co-operation), designed to upgrade the teaching capacity of…

  17. Science and Technology Libraries Section. Special Libraries Division. Papers.

    ERIC Educational Resources Information Center

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

    Papers on science and technology library and information services presented at the 1982 International Federation of Library Associations (IFLA) conference include: (1) "The Central Subject Libraries of the Federal Republic of Germany--For Example: The Technische Informationsbibliothek Hannover" by Gerhard Schlitt and Jobst Tehnzen; (2) "The…

  18. Die Gasultrazentrifuge als mediale Projektion des Kalten Krieges

    NASA Astrophysics Data System (ADS)

    Helmbold, Bernd

    Studien der letzten Dekaden nach der Wiedervereinigung von BRD und DDR erweitern die Perspektive der Wissenschaftsgeschichte vom Fokus des Big Science und der technisch-militärisch-industriellen Auseinandersetzung zwischen den zwei Blöcken zu einer globalen Transformation im Konflikt der Supermächte geprägt durch lokale und auch interne Ausformungen.

  19. Ferrofluide - ihre Grundlagen und Anwendungen: Magnetische Flüssigkeiten kontrollieren

    NASA Astrophysics Data System (ADS)

    Odenbach, Stefan

    Strömung und Eigenschaften von Suspensionen kleiner magnetischer Teilchen, so genannten Ferrofluiden, lassen sich durch laborübliche Magnetfelder wesentlich beeinflussen. Dies ergibt neue Möglichkeiten in der Grundlagenforschung und erlaubt die Entwicklung interessanter technischer Anwendungen. So werden Ferrofluide beispielsweise im Dämpfungs- und Dichtungsbereich, in jüngerer Zeit auch im biomedizinischen Bereich eingesetzt.

  20. "Crafts and Technology" and "Technical Education" in Austria

    ERIC Educational Resources Information Center

    Seiter, Josef

    2009-01-01

    In Austria, the syllabus for "Technisches Werken/Crafts and Technology" for all types of school in general education was issued more than 30 years ago. The authors believed that it might lay the foundations for technical literacy. The paper is about how the situation of the subject and, with it, technical education has developed since then in…

  1. Anforderungskatalog fur Einen Graphikfahigen Mikrocomputer fur Online-Recherchen. Report UBTUW-84-007 (Requirements for a Microcomputer with Graphic Capabilities for Online Searching).

    ERIC Educational Resources Information Center

    Stebegg, K.; Oberhauser, O.

    This paper is primarily an annotated listing of criteria for selection of a microcomputer to be used for online information retrieval. The paper was used by the University Library of the Technische Universitat Wien (Vienna, Austria) while preparing to contact computer dealers and to inform them about the library's needs in this specialized area of…

  2. 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.

  3. “&ldots;how the right technique emerged at the right time” Zur Geschichte der fotografischen Methode im Kalten Krieg

    NASA Astrophysics Data System (ADS)

    Fengler, Silke

    Die Frühgeschichte der fotografischen Methode, die als Nachweisinstrument kernphysikalischer und kosmischer Strahlung in den 1950er Jahren zur Blüte kam, hat das Interesse vieler Wissenschaftshistoriker gefunden. Peter Galison hat gezeigt, wie fragil das Experimentalsystem lange Zeit war, das sich um die Methode bildete, und wie prekär die mit ihr aufgezeichneten Ergebnisse.

  4. VDI-Richtlinien - mit Technischen Regeln Wirtschaftlichkeit erhöhen und Standards setzen

    NASA Astrophysics Data System (ADS)

    Mandelartz, Johannes

    Der Verein Deutscher Ingenieure e.V. (VDI) ist ein gemeinnütziger, wirtschaftlich und politisch unabhängiger, technisch-wissenschaftlicher Verein von Ingenieuren und Naturwissenschaftlern. Mit über 137 000 persönlich zugeordneten Mitgliedern ist er eine der größten Ingenieur-Vereinigungen Europas und gilt in Deutschland als führender Sprecher der Technik und der Ingenieure. 1856 gegründet, hat er viele für die Technik wesentliche Entwicklungen in Gang gesetzt, so im Bereich der technischen Überwachung, der technischen Regelsetzung und Normung, der Arbeitsstudien, im gewerblichen Rechtsschutz und im Patentwesen. Seit seiner Gründung sieht es der VDI als seine Aufgabe, "das Zusammenwirken aller geistiger Kräfte der Technik im Bewusstsein ethischer Verantwortung zu fördern“ und die Lebensmöglichkeiten aller Menschen durch Entwicklung und sinnvoller Anwendung technischer Mittel zu verbessern.

  5. 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.

  6. Von Humboldt bis Einstein. Berlin als Weltzentrum der exakten Wissenschaften.

    NASA Astrophysics Data System (ADS)

    Meschkowski, H.

    Contents: 1. Die Anfänge. 2. Die Ära Dirichlet-Jacobi. 3. Der Ausbau der experimentellen Naturwissenschaften. 4. Alexander von Humboldt. 5. Berlin wird "Weltzentrum" der Mathematik. 6. Die Ära Helmholtz. 7. Neue Arbeitsweisen der Astronomie. 8. Chemie: Forschung und Industrie. 9. Max Planck. 10. Ins technische Zeitalter. 11. Zur Mathematik der zwanziger Jahre. 12. Albert Einstein. 13. Fortschritte der Grundlagenforschung. 14. Erwin Schrödinger: Physiker, Philosoph und Poet. 15. Zum Schluß.

  7. Bauteiluntersuchungen

    NASA Astrophysics Data System (ADS)

    Murrenhoff, Hubertus

    Die Untersuchung der Beeinflussung der Zahnflankentragfähigkeit durch den Einsatz von PVD-Hartstoffschichten in Kombination mit Esterölen ist eine zentrale Aufgabe im SFB 442. Im Laufe des Projekts werden hierfür verschiedene Analogieversuche sowie standardisierte Testverfahren eingesetzt, mit denen eine Vielzahl von Untersuchungen durchgeführt wird. In diesem Kapitel werden zunächst die verwendeten Prüfverfahren erläutert und im Anschluss die erzielten Ergebnisse zusammenfassend dargestellt.

  8. First 2D-ACAR Measurements on Cu with the new Spectrometer at TUM

    NASA Astrophysics Data System (ADS)

    Weber, J. A.; Böni, P.; Ceeh, H.; Leitner, M.; Hugenschmidt, Ch

    2013-06-01

    The two-dimensional measurement of the angular correlation of the positron annihilation radiation (2D-ACAR) is a powerful tool to investigate the electronic structure of materials. Here we report on the first results obtained with the new 2D-ACAR spectrometer at the Technische Universitat München (TUM). To get experience in processing and interpreting 2D-ACAR data, first measurements were made on copper. The obtained data are treated with standard procedures and compared to theoretical calculations. It is shown that the measurements are in good agreement with the calculations and that the Fermi surface can be entirely reconstructed using three projections only.

  9. The performance of primary Cs beam clocks using quadrupole and hexapole deflection systems. Consequences for time keeping

    NASA Technical Reports Server (NTRS)

    Becker, G.

    1979-01-01

    Since 1978 the time-and-frequency standard CS1 of the Physikalisch-Technische Bundesanstalt (PTB) has operated continuously as a 'primary clock'. Its uncertainty (7.1 to the negative 15th power) is considerably smaller than that of the other existing primary standards. The CS1 is equipped with a combination of quadrupole and hexapole magnets and uses a longitudinal C-field. Consequences of utilizing primary clocks of this quality for the generation of the International Atomic Time Scale TAI are discussed.

  10. Optical-Fiber Power Meter Comparison Between NIST and PTB

    PubMed Central

    Vayshenker, I.; Haars, H.; Li, X.; Lehman, J. H.; Livigni, D. J.

    2003-01-01

    We describe the results of a comparison of reference standards between the National Institute of Standards and Technology (NIST-USA) and Physikalisch-Technische Bundesanstalt (PTB-Germany) at nominal wavelengths of 1300 nm and 1550 nm using an optical-fiber cable. Both laboratories used thermal detectors as reference standards. A novel temperature-controlled, optical-trap detector was used as a transfer standard to compare two reference standards. Measurement results showed differences of less than 1.5 × 10−3, which is within the combined uncertainty for both laboratories.

  11. European dosimetry activities for the ISS.

    PubMed

    Reitz, G

    2001-01-01

    In cooperation with the University of Kiel, the University GH of Siegen, the Physikalisch-Technische Bundesanstalt in Braunschweig, the Atomic Energy Research Institute in Budapest and the Institute for Biomedical Problems in Moscow, DLR performed measurements of the radiation environment inside and outside spacecrafts on numerous missions with the main objective to determine as precise as possible the radiation exposure of the astronauts. This report comprises some selected results of recent manned missions and indicates where improvements should be achieved and closes with the description of future measurements planned onboard the International Space Station (ISS). PMID:11780620

  12. LSWAVE 2000: Lasers and short-wavelength applications

    NASA Astrophysics Data System (ADS)

    Sandner, W.

    2001-07-01

    LSWAVE 2000 was organized as a Satellite Workshop to the Seventh International Conference on Synchrotron Radiation Instrumentation SRI 2000. It was held on Saturday, August 26, 2000, at the Technische Universität Berlin, and was jointly organized by the Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy (MBI) and the Technical University Berlin (TUB). The organizing committee consisted of Wilhelm Raith (chairman), Wolfgang Sandner, Ingolf Hertel, Manfred Wick, Bernd Winter, Tatjana Gießel, Holger Stiel, Ingo Will, Ursula Bayr (secretary) and Silvia Szlapka (secretary). Continuing information on the Workshop and its proceedings may be found under http://www.mbi-berlin.de/lswave2000/.

  13. Traceable terahertz power measurement by using optical methods

    NASA Astrophysics Data System (ADS)

    Steiger, Andreas; Gutschwager, Berndt; Meindl, Peter; Monte, Christian; Müller, Ralf; Werner, Lutz; Hollandt, Jörg

    2009-09-01

    In order to exploit new possibilities of THz sensing and imaging, it is not only necessary to generate and detect THz radiation but also to measure the radiant power of the THz sources and the responsivity of the detecting systems traceable to the international system of units (SI). This has been missing in the THz range up to now. The Physikalisch- Technische Bundesanstalt (PTB) has focused on this challenging task by using two complementary optical approaches: source- and detector-based THz radiometry. Both methods have been successfully prototyped, and a pyroelectric THz detector with known aperture was used to verify the consistency of the two independent calibration methods.

  14. Calorimetric support of directional-hemispherical reflection measurements in the infrared spectral range.

    PubMed

    Richter, W; Sarge, S M; Kämmer, F

    1994-03-01

    Measurements of the directional-hemispherical reflectance ρ with the Physikalisch-Technische Bundesanstalt IR sphere reflectometer have been confirmed by calorimetric determination of the absorptance α in the same geometrical conditions (irradiation at 10°, hemispherical reflection). The good agreement of ρ with (1 - α) on both highly reflecting and low-reflecting surfaces indicates that in the mid-IR spectral range the integrating sphere reflectometer is capable of essentially correct reflectance measurements of diffusely reflecting surfaces, with an estimated uncertainty of 0.01 after correction for a small systematic deviation. This capability opens up the possibility of developing IR reflectance standards. PMID:20862150

  15. UV and VUV calibration capabilities at the Metrology Light Source for solar and atmospheric research

    NASA Astrophysics Data System (ADS)

    Klein, R.; Gottwald, A.; Kolbe, M.; Richter, M.; Scholze, F.; Thornagel, R.; Ulm, G.

    2013-05-01

    The Physikalisch-Technische Bundesanstalt (PTB), Germany's national metrology institute, is responsible for the realization and dissemination of the legal units in Germany. Within this mission, PTB has been using synchrotron radiation for the realization of the radiometric units in the spectral range from the UV to the X-ray region for more than 25 years. Prominent examples for calibration work using synchrotron radiation performed by PTB within the framework of solar or atmospheric research refer, e.g., to the SUMER and CDS spectrometers of the SOHO mission, the LYRA mission, or the SOL-ACES and the SOLSPEC instruments on ISS.

  16. Das menschliche Gehör und Grundlagen der Psychoakustik

    NASA Astrophysics Data System (ADS)

    Genuit, Klaus; Sottek, Roland

    Das menschliche Gehör ist ein äußerst komplexes Empfangs- und Signalverarbeitungssystem. Es ist als Schallanalysator in Leistungsfähigkeit und Vielseitigkeit von technisch-analytischen Verfahren nach wie vor unerreicht. Die Signalverarbeitung läuft auf Grundlage komplexer Prozesse ab, die in ihrer Gesamtheit bislang nicht vollständig erfasst sind. Verschiedene Modelle zur gehörgerechten Zeit- und Frequenzanalyse ahmen jene komplexen Prozesse und Verarbeitungsmechanismen nach, die im menschlichen Gehör vollzogen werden.

  17. Supraleitung und Interkontinentalraketen „On-line computing“ zwischen Militär, Industrie und Wissenschaft

    NASA Astrophysics Data System (ADS)

    Knolle, Johannes; Joas, Christian

    Der zweite Weltkrieg und der Kalte Krieg veränderten nicht nur das Verhältnis zwischen Militär, Industrie und Wissenschaft, sondern auch die wissenschaftliche Praxis von Physikern und anderen Wissenschaftlern. In den 1950er Jahren stellte die Entwicklung von Interkontinentalraketen die Auftragnehmer des Militärs in der Industrie vor komplexe Fragestellungen, zu deren Lösung sie auf die Expertise von Wissenschaftlern angewiesen waren. Industrieunternehmen gründeten eigene Forschungseinheiten zur Lösung technischer und wissenschaftlicher Probleme.

  18. Fahrerverhaltensmodelle

    NASA Astrophysics Data System (ADS)

    Donges, Edmund

    Die aktive Teilnahme am Straßenverkehr als Fahrer eines Kraftfahrzeugs ist eine komplexe Überwachungs- und Regelungsaufgabe, für deren Gelingen der Fahrer bei heutiger Rechtslage und heutigem Stand der Technik voll verantwortlich ist. Um ihm für diese Aufgabenstellung die bestmöglichen Arbeitsbedingungen zu verschaffen, muss die Auslegung der technisch gestaltbaren Komponenten des Straßenverkehrssystems die Anpassung an die besondere Leistungsfähigkeit des Menschen, aber auch an seine inhärenten Leistungsgrenzen zum Ziel haben. Dies gilt in vollem Umfang auch für Fahrerassistenzsysteme.

  19. Is there an influence of the surrounding material on the response of the alanine dosimetry system?

    NASA Astrophysics Data System (ADS)

    Anton, Mathias; Kapsch, Ralf-Peter; Hackel, Thomas

    2009-04-01

    In a combined experimental and Monte Carlo study the possible influence of the surrounding material on the response of the alanine dosimetry system was investigated. The aim of this work was to estimate the uncertainties induced by the surroundings with respect to quality assurance measurements for radiotherapy, for example in humanoid phantoms. Six different materials were tested. The electron density range covered comprises the range present in human tissue. No significant influence of the surrounding material could be found for irradiations in the 60Co reference field of the Physikalisch-Technische Bundesanstalt (PTB).

  20. Keller oder Dach zuerst?

    NASA Astrophysics Data System (ADS)

    Megow, Nicole

    Komplexe Planungsaufgaben entstehen in vielen Bereichen wie z. B. in der Produktion und Logistik, der Bauplanung oder allgemein im Projektmanagement. Typischerweise werden umfangreiche Projekte in viele einzelne Teilaufgaben zerlegt, die dann zeitlich geplant werden. Das heißt, es wird genau bestimmt wann bzw. in welcher Reihenfolge Aufgaben mit welchen Ressourcen durchgeführt warden sollen. Bei der Planung müssen verschiedenste Reihenfolgeabhängigkeiten zwischen den Vorgängen berücksichtigt werden. Diese Abhängigkeiten können technischer Natur sein oder werden aus sicherheitsrelevanten oder wirtschaftlichen Gründen festgelegt.

  1. Spectral radiance calibrations between 165-300 nm - An interlaboratory comparison

    NASA Technical Reports Server (NTRS)

    Bridges, J. M.; Ott, W. R.; Pitz, E.; Schulz, A.; Einfeld, D.; Stuck, D.

    1977-01-01

    The spectral radiance of deuterium lamps calibrated by the Max-Planck-Institut fuer Astronomie (MPI), by the U.S. National Bureau of Standards (NBS), and by the Physikalisch-Technische Bundesanstalt (PTB) are compared to check the agreement of UV radiometric scales. The NBS group used the optically thin continuum radiation from a wall-stabilized hydrogen arc as its fundamental radiometric standard, while the MPI and PTB groups used the synchrotron radiation facility in DESY. It is found that the spectral radiance scales based upon the DESY synchrotron and the NBS hydrogen arc are consistent, at least for one wavelength relative to another.

  2. Einblicke in die Dynamik von Quantensystemen: Elektrostatische Speicherringe

    NASA Astrophysics Data System (ADS)

    Welsch, Carsten P.

    2005-03-01

    Elektrostatische Speicherringe kombinieren die Vorteile elektrostatischer Fallen und klassischer magnetischer Speicherringe. Kompaktheit, gute Zugänglichkeit sämtlicher Elemente, hohe Flexibilität in der Wahl möglicher Experimente und die Eigenschaft, alle Teilchen unabhängig von ihrer Masse über einen weiten Geschwindigkeitsbereich zu speichern, bieten Zugang zu einem weiten experimentellen Spektrum. Insbesondere das Potenzial, das in neuartigen, energievariablen Maschinen in Kombination mit Elektronenkühlung, internen Targets und hochauflösenden Reaktionsmikroskopen steckt, verspricht hochinteressante Ergebnisse mit den unterschiedlichsten Teilchen - von exotischen Antiprotonen oder schweren radioaktiven Ionen bis hin zu einfachen und komplexen Molekülen oder Biosystemen.

  3. Echtzeitfähigkeit von Satellitenkompassen in der Binnenschifffahrt

    NASA Astrophysics Data System (ADS)

    Haberkamp, G.; Zöbel, D.

    In der maritimen Schifffahrt finden Satellitenkompasse schon seit längerem Verwendung. Nachdem diese Geräte immer erschwinglicher werden, stellt sich die Frage, ob sie auch als Multisensoren für Telematikanwendungen in der Binnenschifffahrt geeignet sind. Im Rahmen einer umfassenden Untersuchung wurde auch die Fragestellung untersucht, wie zeitnah die Sensorinformationen verfügbar werden. Es wurde ein Versuchsaufbau entwickelt, der es ermöglicht, Satellitenkompasse auf ihre Echtzeitfähigkeit hin zu überprüfen. Das vorliegende Papier beschreibt den entwickelten Versuchsaufbau, dokumentiert die Ergebnisse und gibt einen Ausblick auf Verbesserungspotenziale.

  4. Characteristics of natural wind simulations in the TUM boundary layer wind tunnel

    NASA Astrophysics Data System (ADS)

    Kozmar, Hrvoje

    2011-11-01

    The boundary layer wind tunnel at the Technische Universität München was tested for atmospheric boundary layer (ABL) simulations. The ABLs developing above rural, suburban, and urban terrains were reproduced using the Counihan method, i.e., castellated barrier wall, vortex generators, and a fetch of surface roughness elements. A series of flow-characteristic evaluations was performed to investigate the flow development and uniformity. Experimental results presented as mean velocity, turbulence intensity, integral length scale of turbulence, Reynolds stress, and power spectral density of velocity fluctuations were compared with the ESDU data and/or theoretical models. Generated ABL wind-tunnel simulations compare well with the rural, suburban, and urban ABLs. In the test section area used for experiments on structural models, the ABL simulation is developed and uniform. Results of this study indicate the boundary layer wind tunnel at the Technische Universität München can be successfully employed in a broad spectrum of engineering, environmental, and micrometeorological studies, where it is required to accurately reproduce ABL characteristics.

  5. Patentierung und Patentlage

    NASA Astrophysics Data System (ADS)

    Herrmann, Uwe

    Gewerbliche Schutzrechte nehmen in der nationalen Rechts- und Wirtschaftsordnung sowie auch auf internationaler Ebene stetig an Bedeutung zu. Sie dienen dem Schutz geistigen Eigentums und sind für jeden Gewerbetreibenden nicht nur im Hinblick darauf von Bedeutung, eigene Rechte zu sichern, sondern auch insofern von Relevanz, dass ein Verstoß gegen Rechte Dritter zu vermeiden ist. Zu den gewerblichen Schutzrechten gehören unter anderem Kennzeichenrechte, Geschmacksmusterrechte sowie die sogenannten technischen Schutzrechte in Form des Patents sowie des Gebrauchsmusters. Die folgenden Ausführungen befassen sich ausschließlich mit den technischen Schutzrechten und geben eine kurze Einführung in die Voraussetzungen, das Entstehen und den Wegfall sowie in die Wirkungen technischer Schutzrechte. Beleuchtet wird die Situation im Wesentlichen im Hinblick auf nationale technische Schutzrechte, d. h. auf Deutsche Patente und Gebrauchsmuster sowie auf Europäische Patente, die Schutz in Deutschland entfalten. Die Möglichkeit der Erlangung von Schutzrechten im außereuropäischen Ausland wird nur am Rande gestreift.

  6. The interaction between sediment, hydraulics and mussels in a river

    NASA Astrophysics Data System (ADS)

    Schwarzwälder, Kordula

    2015-04-01

    Sarah Scholtissek Technische Universität München, Hydraulic and Water Resources Engineering, München, Germany Peter Rutschmann Technische Universität München, Hydraulic and Water Resources Engineering, München, Germany Bottom structures in rivers are not only depending on the current profile, turbulence in the flow and other hydraulic conditions, but also on the biota living in the river like e.g. mussels. There is also some influence of the sediment on the biota and their decision where they settle and so on. The interaction between the current, the mussels and the sediment is actually not very well known, especially in fresh waters. Therefore experiments were cunducted in a flume in the lab in Obernach to gain more information about these interactions. The mussels used for these experiments are painters mussels (Unio Pictorum). These mussels are widely spreaded in European fresh waters, but their behaviour is also comparable to mussels which are more sensitive and therefore rare like the pearl mussel (Margaritifera Margaritifera). In the experiments 15 individuals are monitored how they move and spread in the flume. Then the hydraulic conditions and the sediment around the mussels are measured with laser scanning and PIV (particle image velocimetry). with the help of these measurement techniques it is possible to do contactless measurements even of the small eddies around and caused by the mussels which exist only for a very short time but have an enormous effect on the sediment.

  7. [Evidenzbasierte Leitlinien, Anspruch und Wirklichkeit].

    PubMed

    Gutsch, Johannes; Reif, Marcus; Müller-Hübenthal, Boris; Matthiessen, Peter F

    2016-01-01

    Mit der Konzeption der «Evidenzbasierten Medizin» und den «Evidenzbasierten Leitlinien» soll mithilfe von Formalisierungsprozeduren die ärztliche Irrtumsanfälligkeit kalkulierbar gemacht werden. Quantifizierte objektive Aussagen über die therapeutische Wirksamkeit einer Behandlung sollen die individuelle ärztliche Beurteilung der therapeutischen Wirksamkeit überflüssig machen. Damit kommt der Befolgung von formalen Regeln die entscheidende Rolle bei der Beantwortung der Frage nach dem Wahrheitsgehalt und dem Wirklichkeitsbezug zu. Im Rahmen evidenzbasierter Leitlinien werden vorrangig die Ergebnisse randomisierter kontrollierter Studien (RCT) oder Meta-Analysen solcher Studien herangezogen. Am Beispiel der S3-Leitlinie «Malignes Melanom» wird hier eine evidenzbasierte Urteilsbildung zur Wirksamkeit einer unkonventionellen Therapie - hier mit einem Mistelpräparat - analytisch nachvollzogen. Die für die Beurteilung dieser unkonventionellen Therapie herangezogene randomisierte Studie wird genauer methodisch analysiert. Obwohl sie keine statistisch basierte Aussage zulässt, wurde eine Leitlinienempfehlung auf Basis dieser Studie abgeleitet. Es wird gezeigt, dass 1) allein die Existenz einer einzigen RCT mit hoher Evidenz gleichgesetzt wird, 2) die Ergebnisse trotz beträchtlicher Fehlinterpretationen in eine S3-Leitlinie einfließen und 3) Meinungen anstelle kritischer wissenschaftlicher Analysen verarbeitet werden. Unsere Untersuchung zeigt, dass noch so ausgefeilte epistemologische und methodologische Formalien den Arzt nicht von der Pflicht entbinden, auf Basis seiner ärztlichen Erfahrung und professionellen Kompetenz den Realitätswert der ihm zur Verfügung stehenden Information zu beurteilen. PMID:27161555

  8. [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

  9. Homogeneous reprocessing of GPS, GLONASS and SLR observations

    NASA Astrophysics Data System (ADS)

    Fritsche, Mathias; Sośnica, Krzysztof; Rodríguez-Solano, Carlos Javier; Steigenberger, Peter; Wang, Kan; Dietrich, Reinhard; Dach, Rolf; Hugentobler, Urs; Rothacher, Markus

    2014-07-01

    The International GNSS Service (IGS) provides operational products for the GPS and GLONASS constellation. Homogeneously processed time series of parameters from the IGS are only available for GPS. Reprocessed GLONASS series are provided only by individual Analysis Centers (i. e. CODE and ESA), making it difficult to fully include the GLONASS system into a rigorous GNSS analysis. In view of the increasing number of active GLONASS satellites and a steadily growing number of GPS+GLONASS-tracking stations available over the past few years, Technische Universität Dresden, Technische Universität München, Universität Bern and Eidgenössische Technische Hochschule Zürich performed a combined reprocessing of GPS and GLONASS observations. Also, SLR observations to GPS and GLONASS are included in this reprocessing effort. Here, we show only SLR results from a GNSS orbit validation. In total, 18 years of data (1994-2011) have been processed from altogether 340 GNSS and 70 SLR stations. The use of GLONASS observations in addition to GPS has no impact on the estimated linear terrestrial reference frame parameters. However, daily station positions show an RMS reduction of 0.3 mm on average for the height component when additional GLONASS observations can be used for the time series determination. Analyzing satellite orbit overlaps, the rigorous combination of GPS and GLONASS neither improves nor degrades the GPS orbit precision. For GLONASS, however, the quality of the microwave-derived GLONASS orbits improves due to the combination. These findings are confirmed using independent SLR observations for a GNSS orbit validation. In comparison to previous studies, mean SLR biases for satellites GPS-35 and GPS-36 could be reduced in magnitude from and mm to and mm, respectively. Our results show that remaining SLR biases depend on the satellite type and the use of coated or uncoated retro-reflectors. For Earth rotation parameters, the increasing number of GLONASS satellites and

  10. Galileo, Cassini, Giotto. Raumsonden erforschen unser Planetensystem

    NASA Astrophysics Data System (ADS)

    Engelhardt, Wolfgang

    Großartige Bilder und andere wichtige Informationen von den Planeten Merkur bis Neptun sowie von Asteroiden und Kometen haben zahlreiche amerikanische und russische, europäische und japanische Raumsonden seit 1960 zur Erde gefunkt. Die interplanetare Raumfahrt bewährt sich als verlängertes Teleskop der Astronomen, und die Ergebnisse sind nicht nur für Wissenschaftler interessant, sie erweitern auch den menschlichen Erkenntnishorizont insgesamt. Die Raketentechnik und moderne Elektronik bzw. Sensorik haben sich zu einem fantastischen Instrument der Astronomie und Planetenforschung verbunden. Allgemeinverständlich werden in diesem Buch die historische, erdgebundene Entwicklung der Planetenforschung und die Ergebnisse der seit 45 Jahren startenden automatischen Raumsonden, die natürlich viel näher an die fernen Himmelskörper herankommen, vor dem Leser ausgebreitet. So wissen wir heute sehr gut über das Aussehen und die Beschaffenheit der meisten kleinen und großen Planeten, ihrer Oberflächen und Atmosphären, die verschiedenartigen Monde und Ringsysteme, Magnetfelder und Strahlengürtel Bescheid. Den zweiten Schwerpunkt des Buches bildet die Beschreibung der vielen Raumsonden und ihrer oft jahrelangen, aufregenden Missionen zur Erforschung von Sonne, Merkur, Venus, Erde und Mond, Mars, Jupiter, Saturn, Uranus und Neptun sowie diverser Kometen und Asteroiden. Dabei wird die Konstruktion der Elektronikroboter mit allen Anlagen zur Energieversorgung, Temperaturkontrolle, Funkverbindung und Lagekontrolle ebenso erläutert wie die Multispektralinstrumente und die Beobachtungsstrategien beim Erreichen der fernen Reiseziele. Unvergessen sind die fantastischen Ergebnisse der amerikanischen Mariner- und Viking-Sonden von Mars die großartigen Bilder und Messungen der Voyager-Späher von den großen äußeren Gasplaneten. Auch die neuesten Resultate der Galileo-Sonde von Jupiter und seinen vier großen Monden sowie des Cassini-Orbiters von Saturn und seinem

  11. New prospects in solar cooking

    SciTech Connect

    Grupp, M.; Klingshirn, A.

    1992-12-31

    Two studies have been completed recently for Gesellschaft fur Technische Zusammenarbeit and German Appropriate Technology Exchange. The first of these studies contains the following: a classification scheme for solar cookers according to collector type, heat transfer mechanism, and type of use; an assessment of the potential interest of different cooker concepts; a catalogue of 160 different solar cookers that have been tested and/or used in the field. The second study highlights the potential advantages of multi-energy (solar plus back-up) cooking and analyzes its particular boundary conditions. A choice of possible concepts for use in institutions is presented. Particular attention is paid to the problem of efficient heat transfer into removable cooking vessels. Social and cultural factors concerning the acceptance of new technologies are also discussed.

  12. Response function stability of single crystal diamond detectors to 14 MeV neutrons

    SciTech Connect

    Zbořil, Miroslav Zimbal, Andreas

    2014-11-15

    Detectors based on single crystal synthetic diamond show promise as neutron spectrometers for the ITER project. In this work, the stability of the response function of two diamond detectors was tested at the Physikalisch-Technische Bundesanstalt (PTB) accelerator using a 14 MeV neutron field and a method of time-resolved fluence monitoring. In addition, measurements at the PTB ion-microbeam were made to investigate the charge collection properties of the detectors in more detail. The {sup 12}C(n,α){sup 9}Be peak response of one of the detectors was found to be stable within 1% after irradiation with a neutron fluence of 8 × 10{sup 9} cm{sup −2}. The absolute value of the peak response of this detector was determined as 8.65(26) × 10{sup −5} cm{sup 2}.

  13. Demonstration of the two-chamber approach for high-voltage measurements using collinear laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Will, Elisa; Ullmann, Johannes; Frömmgen, Nadja; Geppert, Christopher; Gorges, Christian; Hammen, Michael; Kaufmann, Simon; Krieger, Andreas; Nörtershäuser, Wilfried

    2014-06-01

    An electronic measurement of high-voltages of several ten kV with accuracy as required for precision experiments is currently only feasible using highly sophisticated voltage dividers. Collinear laser spectroscopy can provide a direct and precise measurement of high-voltages using the Doppler shift of accelerated ions. Although proposed already in 1982, a measurement with relative accuracy better than 10-4 was not reported so far. To improve this accuracy, a dedicated new setup for high-voltage measurements will be installed at the Technische Universität Darmstadt. A two-chamber approach will be used to remove uncertainties due to the insufficiently known starting potential inside the ion source. Here we present a demonstration of the pump-and-probe technique performed in preparatory studies at the TRIGA-LASER experiment in Mainz.

  14. An in-flight blackbody calibration source for the GLORIA interferometer onboard an airborne research platform

    NASA Astrophysics Data System (ADS)

    Koppmann, R.; Olschewski, F.; Steffens, P.; Rolf, C.; Preusse, P.; Ebersoldt, A.; Friedl-Vallon, F.; Kleinert, A.; Piesch, C.; Hollandt, J.; Gutschwager, B.; Monte, C.

    2013-05-01

    The Gimballed Limb Observer for Radiance Imaging of the Atmosphere (GLORIA) deployed on board different research aircraft provides detailed pictures of the Upper Troposphere/Lower Stratosphere (UTLS) region. GLORIA uses a two-dimensional detector array for infrared limb observations. GLORIA's in-flight calibration sources are two identical large-area high-precision blackbodies, which are independently controlled at two different temperatures. Thermo-Electric Coolers (TECs) are used to control the temperature of the calibration sources. The calibration sources have been comprehensively characterized for their spatially and spectrally resolved radiation properties in terms of radiation temperature traceable to the International Temperature Scale (ITS-90) at the Physikalisch-Technische Bundesanstalt (PTB), the national metrology institute of Germany.

  15. Traceable calibration of a fibre-coupled superconducting nano-wire single photon detector using characterized synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Müller, Ingmar; Klein, Roman M.; Werner, Lutz

    2014-12-01

    Radiometric calibrations of fibre-coupled single photon detectors are experiencing growing demand, especially at the telecommunication wavelengths. In this paper, the radiometric calibration of a fibre-coupled superconducting nano-wire single photon detector at the telecom wavelength 1.55 µm by means of well-characterized synchrotron radiation is described. This substitution method is based on the unique properties of synchrotron radiation and the Metrology Light Source, the dedicated electron storage ring of the Physikalisch-Technische Bundesanstalt, and is suitable for fibre-coupled single photon detectors. The Metrology Light Source is used as a light source with a high dynamic range of the radiant power to bridge the radiometric gap occurring in the transition from radiant power measurements and the counting of photons with single photon detectors. Very low uncertainties below 2% have been achieved in the measurement of the detection efficiency of a fibre-coupled superconducting nano-wire single photon detector.

  16. 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.

  17. Response function stability of single crystal diamond detectors to 14 MeV neutrons.

    PubMed

    Zbořil, Miroslav; Zimbal, Andreas

    2014-11-01

    Detectors based on single crystal synthetic diamond show promise as neutron spectrometers for the ITER project. In this work, the stability of the response function of two diamond detectors was tested at the Physikalisch-Technische Bundesanstalt (PTB) accelerator using a 14 MeV neutron field and a method of time-resolved fluence monitoring. In addition, measurements at the PTB ion-microbeam were made to investigate the charge collection properties of the detectors in more detail. The (12)C(n,α)(9)Be peak response of one of the detectors was found to be stable within 1% after irradiation with a neutron fluence of 8 × 10(9) cm(-2). The absolute value of the peak response of this detector was determined as 8.65(26) × 10(-5) cm(2). PMID:25430252

  18. Development of forced flow cooled current leads for fusion magnets

    NASA Astrophysics Data System (ADS)

    Heller, R.; Fink, S.; Friesinger, G.; Kienzler, A.; Lingor, A.; Schleinkofer, G.; Süßer, M.; Ulbricht, A.; Wüchner, F.; Zahn, G.

    2001-03-01

    During the past 15 years, the Institut für Technische Physik of the Forschungszentrum Karlsruhe, Germany, has developed current leads cooled by forced-flow supercritical helium in the current range from 20 to 80 kA. The design is based on a separation of the current carrying part and the heat exchanger part as well as the presence of the so-called superconductor inserts made of Nb 3Sn wires inside the conductor in the heat exchanger area which allows the operation of the current lead at minimum helium mass flow in a wide current range. The paper describes the design and construction of the current leads as well as operation results obtained during various tests performed in the coil test facility TOSKA at the Forschungszentrum Karlsruhe.

  19. A new method for determining allowable medium temperature during transient operation of thick-walled elements in a supercritical power plant

    NASA Astrophysics Data System (ADS)

    Duda, Piotr; Rząsa, Dariusz

    2010-09-01

    Construction elements of supercritical power plants are subjected to high working pressures and high temperatures while operating. Under these conditions high stresses in the construction are created. In order to operate safely, it is important to monitor stresses, especially during start-up and shut-down processes. The maximum stresses in the construction elements should not exceed the allowable stress limit. The goal is to find optimum operating parameters that can assure safe heating and cooling processes [1-5]. The optimum parameters should guarantee that the allowable stresses are not exceeded and the entire process is conducted in the shortest time. In this work new numerical method for determining optimum working parameters is presented. Based on these parameters heating operations were conducted. Stresses were monitored during the entire processes. The results obtained were compared with the German boiler regulations - Technische Regeln für Dampfkessel 301.

  20. Diagnostic analysis of the Lake Uluabat in Turkey.

    PubMed

    Degirminci, Hasan; Alp, Ahmet; Buyukcangaz, Hakan

    2006-05-01

    Diagnostic analysis of wetlands is an ordered/structured method of examining wetland systems to identify their values and constraints for the solution of the environmental problems. This study focuses on the diagnostic analysis of Lake Uluabat on the feasibility of "Objective Oriented Project Planning (OOPP)" approach, created by the United States Agency for International Development (USAID) and further improved by the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ). Negative changes both in water quality and quantity were determined as the core problems. The main results were summarized as the water pollution and fluctuation in the water level caused by the urban and agricultural waste disposals, sedimentation, and overfishing. These negative effects cause loss of biodiversity and damage to crops. Disposal control, training, adequate regulations, and a centralized control and monitoring authority have been proposed to cope with the determined problems. PMID:17436539

  1. Fully automated hybrid diode laser assembly using high precision active alignment

    NASA Astrophysics Data System (ADS)

    Böttger, Gunnar; Weber, Daniel; Scholz, Friedemann; Schröder, Henning; Schneider-Ramelow, Martin; Lang, Klaus-Dieter

    2016-03-01

    Fraunhofer IZM, Technische Universität Berlin and eagleyard Photonics present various implementations of current micro-optical assemblies for high quality free space laser beam forming and efficient fiber coupling. The laser modules shown are optimized for fast and automated assembly in small form factor packages via state-of-the-art active alignment machinery, using alignment and joining processes that have been developed and established in various industrial research projects. Operational wavelengths and optical powers ranging from 600 to 1600 nm and from 1 mW to several W respectively are addressed, for application in high-resolution laser spectroscopy, telecom and optical sensors, up to the optical powers needed in industrial and medical laser treatment.

  2. Reinraumtechnik für die Medizintechnik

    NASA Astrophysics Data System (ADS)

    Petek, Max; Jungbluth, Martin; Krampe, Erhard

    Die Reinraumtechnik ist heute ein unverzichtbarer Bestandteil bei der Fertigung von Produkten der Life Sciences, den Bereichen Pharma, Lebensmittel, Kosmetik und Medizintechnik. In Anbetracht der langen Historie der Medizintechnik ist sie jedoch eine sehr junge Disziplin. Die Bedeutung von Keimen und die richtige Einschätzung ihrer Größe wurden zwar sehr früh bereits durch Paracelsus erkannt, jedoch wurden daraus noch keine speziellen oder kontinuierlich umgesetzten Hygienevorschriften abgeleitet. Die erste bekannte technische Umsetzung von Hygieneempfehlungen geht auf den Franzosen François Nicolas Appert zurück, der eine aseptische Abfüllmethode für Lebensmittel entwickelte und diese 1810 veröffentlichte [1]. Die erste dokumentierte medizinische Umsetzung stellten Hygienevorschriften für Ärzte dar, die Ignaz Philipp Semmelweis nach 1847 in der Wiener Klinik für Geburtshilfe einführte [2].

  3. Measurement of the electron energy and energy spread at the electron storage ring BESSY I.

    PubMed

    Klein, R; Mayer, T; Kuske, P; Thornagel, R; Ulm, G

    1998-05-01

    Knowledge of the electron energy with a small uncertainty is necessary for the Physikalisch-Technische Bundesanstalt (PTB) to operate the electron storage ring BESSY I, and the future BESSY II, as a primary radiation source standard of calculable synchrotron radiation. At BESSY I the electron energy can now be measured either by the long-established method of resonant spin depolarization or by the newly set up method of Compton backscattering (CBS) of laser photons (CO(2) laser, lambda = 10.6 micro m). Results obtained at different electron energies by these two independent methods are presented. They agree within a relative uncertainty of better than 10(-4). The advantages and disadvantages of these two complementary techniques are described and applications of CBS for the measurement of other storage-ring parameters, e.g. the electron energy spread, are given. PMID:15263521

  4. Postirradiation effects in alanine dosimeter probes of two different suppliers.

    PubMed

    Anton, Mathias

    2008-03-01

    The measurand relevant for the dosimetry for radiation therapy is the absorbed dose to water, DW. The Physikalisch-Technische Bundesanstalt (PTB) is establishing a secondary standard for DW for high-energy photon and electron radiation based on electron spin resonance (ESR) of the amino acid alanine. For practical applications, like, for example, intercomparison measurements using the ESR/alanine dosimetry system, the temporal evolution of the ESR signal of irradiated probes is an important issue. This postirradiation behaviour is investigated for alanine pellets of two different suppliers for different storage conditions. The influence of the storage conditions on the temporal evolution may be dependent on the type of probes used. The measurement and analysis method developed at the PTB is able to circumvent the apparent difficulties in the case of alanine/paraffin probes. Care has to be taken in case this method cannot be applied. PMID:18296760

  5. Gernot Renger (1937-2013): his life, Max-Volmer Laboratory, and photosynthesis research.

    PubMed

    Siggel, Ulrich; Schmitt, Franz-Josef; Messinger, Johannes

    2016-08-01

    Gernot Renger (October 23, 1937-January 12, 2013), one of the leading biophysicists in the field of photosynthesis research, studied and worked at the Max-Volmer-Institute (MVI) of the Technische Universität Berlin, Germany, for more than 50 years, and thus witnessed the rise and decline of photosynthesis research at this institute, which at its prime was one of the leading centers in this field. We present a tribute to Gernot Renger's work and life in the context of the history of photosynthesis research of that period, with special focus on the MVI. Gernot will be remembered for his thought-provoking questions and his boundless enthusiasm for science. PMID:27312337

  6. Measuring and interpreting X-ray fluorescence from planetary surfaces.

    PubMed

    Owens, Alan; Beckhoff, Burkhard; Fraser, George; Kolbe, Michael; Krumrey, Michael; Mantero, Alfonso; Mantler, Michael; Peacock, Anthony; Pia, Maria-Grazia; Pullan, Derek; Schneider, Uwe G; Ulm, Gerhard

    2008-11-15

    As part of a comprehensive study of X-ray emission from planetary surfaces and in particular the planet Mercury, we have measured fluorescent radiation from a number of planetary analog rock samples using monochromatized synchrotron radiation provided by the BESSY II electron storage ring. The experiments were carried out using a purpose built X-ray fluorescence (XRF) spectrometer chamber developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute. The XRF instrumentation is absolutely calibrated and allows for reference-free quantitation of rock sample composition, taking into account secondary photon- and electron-induced enhancement effects. The fluorescence data, in turn, have been used to validate a planetary fluorescence simulation tool based on the GEANT4 transport code. This simulation can be used as a mission analysis tool to predict the time-dependent orbital XRF spectral distributions from planetary surfaces throughout the mapping phase. PMID:18855420

  7. Determining orbital particle parameters of impacts into germanium using morphology analysis and calibration data from hypervelocity impact experiments in the laboratory

    NASA Technical Reports Server (NTRS)

    Paul, Klaus G.

    1995-01-01

    This paper describes the work that is done at the Lehrstuhl fur Raumfahrttechnik (lrt) at the Technische Universitat Munchen to examine particle impacts into germanium surfaces which were flown on board the LDEF satellite. Besides the description of the processing of the samples, a brief overview of the particle launchers at our institute is given together with descriptions of impact morphology of high- and hypervelocity particles into germanium. Since germanium is a brittle, almost glass-like material, the impact morphology may also be interesting for anyone dealing with materials such as optics and solar cells. The main focus of our investigations is to learn about the impacting particle's properties, for example mass, velocity and direction. This is done by examining the morphology, various geometry parameters, crater obliqueness and crater volume.

  8. Gebändigtes Knallgas: Brennstoffzellen im mobilen und stationären Einsatz

    NASA Astrophysics Data System (ADS)

    Waidhas, Manfred; Landes, Harald

    2001-07-01

    Die Brennstoffzelle hat aus technischer Sicht einen hohen Stand erreicht. Die PEMFC konnte ihre Zuverlässigkeit in einer Reihe von Nischenanwendungen, aber auch in Form erster mobiler und dezentraler Prototypen beweisen. Die SOFC und die MCFC konnten bereits in Anlagen von 100 kW und mehr in Erprobung gehen. Um jedoch wirtschaftlich konkur-renzfähig zu den etablierten Technologien der mobilen und dezentralen Energiewandlung zu werden, muss noch eine drastische Kostenreduktion sowohl beim Brennstoffzellen-Stack als auch bei den zu seinem Betrieb notwendigen Hilfsaggregaten erreicht werden. Für Fahrzeugantriebe muss außerdem eine Antwort auf die noch offene Treibstofffrage (Infrastruktur, H2-Erzeugung und H2-Speicherung) gefunden werden.

  9. Investigation of Calibrating Force Transducer Using Sinusoidal Force

    SciTech Connect

    Zhang Li; Wang Yu; Zhang Lizhe

    2010-05-28

    Sinusoidal force calibration method was studied several years before at Physikalisch-Technische Bundesanstalt (PTB). A similar dynamic force calibration system is developed at Changcheng Institute of Metrology and Measurement (CIMM). It uses electro-dynamic shakers to generate dynamic force in the range from 1 N to 20 kN, and heterodyne laser interferometers are used for acceleration measurement. The force transducer to be calibrated is mounted on the shaker, and a mass block is screwed on the top of force transducer, the sinusoidal forces realized by accelerated load masses are traceable to acceleration and mass according to the force definition. The methods of determining Spatial-dependent acceleration on mass block and measuring the end mass of force transducer in dynamic force calibration are discussed in this paper.

  10. 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.

  11. Theoretical and experimental determination of L -shell decay rates, line widths, and fluorescence yields in Ge

    NASA Astrophysics Data System (ADS)

    Guerra, M.; Sampaio, J. M.; Madeira, T. I.; Parente, F.; Indelicato, P.; Marques, J. P.; Santos, J. P.; Hoszowska, J.; Dousse, J.-Cl.; Loperetti, L.; Zeeshan, F.; Müller, M.; Unterumsberger, R.; Beckhoff, B.

    2015-08-01

    Fluorescence yields (FYs) for the Ge L shell were determined by a theoretical and two experimental groups within the framework of the International Initiative on X-Ray Fundamental Parameters Collaboration. Calculations were performed using the Dirac-Fock method, including relativistic and QED corrections. The experimental value of the L3FY ωL 3 was determined at the Physikalisch-Technische Bundesanstalt undulator beamline of the synchrotron radiation facility BESSY II in Berlin, Germany, and the L α1 ,2 and L β1 line widths were measured at the Swiss Light Source, Paul Scherrer Institute, Switzerland, using monochromatized synchrotron radiation and a von Hamos x-ray crystal spectrometer. The measured fluorescence yields and line widths are compared to the corresponding calculated values.

  12. High-frame rate imaging of two-phase flow in a thin rectangular channel using fast neutrons.

    PubMed

    Zboray, R; Mor, I; Dangendorf, V; Stark, M; Tittelmeier, K; Cortesi, M; Adams, R

    2014-08-01

    We have demonstrated the feasibility of performing high-frame-rate, fast neutron radiography of air-water two-phase flows in a thin channel with rectangular cross section. The experiments have been carried out at the accelerator facility of the Physikalisch-Technische Bundesanstalt. A polychromatic, high-intensity fast neutron beam with average energy of 6 MeV was produced by 11.5 MeV deuterons hitting a thick Be target. Image sequences down to 10 ms exposure times were obtained using a fast-neutron imaging detector developed in the context of fast-neutron resonance imaging. Different two-phase flow regimes such as bubbly slug and churn flows have been examined. Two phase flow parameters like the volumetric gas fraction, bubble size and mean bubble velocities have been measured. The first results are promising, improvements for future experiments are also discussed. PMID:24709611

  13. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the PTB and the BIPM

    NASA Astrophysics Data System (ADS)

    Kessler, C.; Allisy-Roberts, P. J.; Selbach, H. J.

    2015-01-01

    An indirect comparison of the standards for reference air kerma rate (RAKR) for 192Ir high dose rate (HDR) brachytherapy sources of the Physikalisch-Technische Bundesanstalt (PTB), Germany, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the PTB in September 2011. The comparison result, based on the calibration coefficients for a transfer standard and expressed as a ratio of the PTB and the BIPM standards for reference air kerma rate, is 1.0003 with a combined standard uncertainty of 0.0099. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  14. Umsetzung von CE-Prozessen durch neue Methoden und interaktive 3-D-Modelle

    NASA Astrophysics Data System (ADS)

    Lange, Andrea; Schulz, Torsten; Szymanski, Hans

    Innerhalb der EU gelten einheitliche Anforderungen an die Gestaltung von Maschinen, die in Form von grundlegenden Sicherheits- und Gesundheitsschutzanforderungen in der Maschinenrichtlinie (MaschRL) formuliert sind. Ihre Einhaltung dokumentiert der Hersteller mit der Konformitätserklärung und der Vergabe des CE-Zeichens. Die Maschinenrichtlinie ist ein Element des 1985 von der Europäischen Gemeinschaft (EG) beschriebenen "New Approach“ Rechtsetzungsmodells, das technologische Innovation ermöglicht und die Wettbewerbsfähigkeit der europäischen Industrie regelt. Es wurde erschaffen, um technische Handelshemmnisse im europäischen Binnenmarkt zu beseitigen und ein einheitliches Niveau hinsichtlich der Sicherheit der Produkte und dem Gesundheits- bzw. Verbraucherschutz zu gewährleisten. Alle Produkt-Richtlinien der EG, die später auf Grundlage des New Approach entstanden sind, weisen eine einheitliche Vorgehensweise auf, mit der diese Ziele erreicht werden sollen (VDI Verlag 11/2008).

  15. Analysis of the product gas from biomass gasification by means of laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Karellas, S.; Karl, J.

    2007-09-01

    The use of biomass and waste for decentralised combined heat and power production (CHP) requires highly efficient gasification processes. In the Technische Universität München (TUM), an innovative gasification technology has been developed. This allothermal gasifier is producing a hydrogen- rich, high-calorific gas, that can be further used in a microturbine or a fuel cell producing energy. For the operation of such a system, the online analysis of the composition of the product gas is of high importance, since the efficient working of the machines is linked with the gas quality. For this purpose an optical measurement system based on laser spectroscopy has been applied. This system can measure not only the basic components of the product gas (H 2, CH 4, CO, CO 2, H 2O), but it also gives information concerning the content of high hydrocarbons, the so-called tars, in the product gas.

  16. PREFACE: 15th International Conference on the Strength of Materials (ICSMA-15)

    NASA Astrophysics Data System (ADS)

    Skrotzki, Werner; Oertel, Carl-Georg; Biermann, Horst; Heilmaier, Martin

    2010-04-01

    . This is a very good ratio showing that we could attract the young generation. There have been 272 oral and 135 poster presentations. It is our pleasure to thank the members of the International ICSMA Committee for their valuable help, especially for proposing and choosing the 18 plenary speakers. 187 papers were submitted for publication in the proceedings, 167 were accepted after reviewing. We would like to express our thanks to all referees for their efficient and prompt efforts. We acknowledge particularly support from the German Research Society (DFG), the Saxon Ministry for Science and Art and the City of Dresden. We are also grateful for industrial support from PLANSEE Metall GmbH, Goodfellow GmbH, MTS Systems GMB, Nagoya University and IOP Publishing. Finally we thank all members of the Local Organizing Committee, Intercom Dresden and Conwerk / Laboratory Ten for the excellent organization of ICSMA 15 and the very pleasant collaboration. During the conference the International ICSMA Committee decided to convene the next conference in Bangalore, India, in 2012. We wish the organizers of ICSMA 16 great success and look forward to meeting you in Bangalore. Werner Skrotzki (Technische Universität Dresden) Carl-Georg Oertel (Technische Universität Dresden) Horst Biermann (Bergakademie Technische Universität Freiberg) Martin Heilmaier (Technische Universität Darmstadt) Guest Editors Dresden, June 23, 2009 (* Corresponding author; e-mail address: werner.skrotzki@physik.tu-dresden.de)

  17. Nuclear physics experiments for the astrophysical p process

    NASA Astrophysics Data System (ADS)

    Sauerwein, A.; Elvers, M.; Endres, J.; Hasper, J.; Hennig, A.; Netterdon, L.; Zilges, A.

    2011-04-01

    We studied the two astrophysically interesting reactions 141PrPm and 92MoTc with the activation method and with the in-beam method, respectively. The 141PrPm experiment was performed at the cyclotron of the ‘Physikalisch Technische Bundesanstalt (PTB)’ in Braunschweig, Germany, and the reaction was studied within and just above the so-called Gamow window. In this proceedings, we present the experimental details of this measurement. The proton-capture reaction on the neutron-magic nucleus 92Mo was studied at energies relevant for the astrophysical p process. The reaction was investigated by the in-beam technique using the γ-ray detector array HORUS (High efficient Observatory for γ-Ray Unique Spectroscopy) at the TANDEM ion accelerator at the University of Cologne. The preliminary experimental results are compared to data stemming from other measurements.

  18. Calibration of far-IR and sub-mm detectors traceable to the international system of units

    NASA Astrophysics Data System (ADS)

    Müller, Ralf; Gutschwager, Berndt; Monte, Christian; Steiger, Andreas; Hollandt, Jörg

    2010-09-01

    Precision power measurement of electromagnetic radiation is required to establish metrological applications, e.g. remote sensing. The Physikalisch-Technische Bundesanstalt (PTB), as the national metrology institute of Germany, has started to determine the spectral responsivity of detectors for THz radiation. In this work, the THz spectral range denotes the wavelength range from 60 μm to 300 μm, corresponding to 5 THz to 1 THz, which is traditionally the overlap between far-IR and the sub-mm range. Traceability of power measurement to the international system of units (SI) has been missing in the THz region in the past. The PTB establishes this traceability by using two complementary optical approaches, source- and detector-based radiometry. Both methods have been successfully prototyped. These primary investigations led to the design of a new measurement facility for the determination of THz radiant power and the responsivity calibration of THz detectors traceable to the SI.

  19. Internet discussion forums as part of a student-centred teaching concept of pharmacology

    PubMed Central

    Sucha, Michael; Engelhardt, Stefan; Sarikas, Antonio

    2013-01-01

    Introduction: The world wide web opens up new opportunities to interconnect electronic and classroom teaching and to promote active student participation. In this project article we describe the use of internet discussion forums as part of a student-centred teaching concept of pharmacology and discuss its advantages and disadvantages based on evaluation data and current literature. Methods and Results: Final year medical students at the Technische Universität München (Munich, Germany) with the elective pharmacology moderated an internet forum that allowed all students to discuss pharmacology-related questions. Evaluation results of forum participants and elective students demonstrated a learning benefit of internet forums in pharmacology teaching. Conclusion: Internet discussion forums offer an easy-to-implement and effective way to actively engage students and increase the learning benefit of electronic and classroom teaching in pharmacology. PMID:23467549

  20. Aerodynamic analysis of a helicopter fuselage with rotating rotor head

    NASA Astrophysics Data System (ADS)

    Reß, R.; Grawunder, M.; Breitsamter, Ch.

    2015-06-01

    The present paper describes results of wind tunnel experiments obtained during a research programme aimed at drag reduction of the fuselage of a twin engine light helicopter configuration. A 1 : 5 scale model of a helicopter fuselage including a rotating rotor head and landing gear was investigated in the low-speed wind tunnel A of Technische Universität a München (TUM). The modelled parts of the helicopter induce approxiu mately 80% of the total parasite drag thus forming a major potential for shape optimizations. The present paper compares results of force and moment measurements of a baseline configuration and modified variants with an emphasis on the aerodynamic drag, lift, and yawing moment coefficients.

  1. Nova reaction rates and experiments

    NASA Astrophysics Data System (ADS)

    Bishop, S.; Herlitzius, C.; Fiehl, J.

    2011-04-01

    Oxygen-neon novae form a subset of classical novae events known to freshly synthesize nuclei up to mass number A≲40. Because several gamma-ray emitters lie in this mass range, these novae are also interesting candidates for gamma-ray astronomy. The properties of excited states within those nuclei in this mass region play a critical role in determining the resonant (p,γ) reaction rates, themselves, largely unknown for the unstable nuclei. We describe herein a new Doppler shift lifetime facility at the Maier-Leibnitz tandem laboratory, Technische Universität München, with which we will map out important resonant (p,γ) nova reaction rates.

  2. Molar-mass measurement of a 28Si-enriched silicon crystal for determination of the Avogadro constant

    NASA Astrophysics Data System (ADS)

    Narukawa, Tomohiro; Hioki, Akiharu; Kuramoto, Naoki; Fujii, Kenichi

    2014-06-01

    The molar mass of a 28Si-enriched crystal was measured at the National Metrology Institute of Japan to determine the Avogadro constant by the x-ray crystal density method as part of the International Avogadro Coordination project. The molar mass was determined by isotope ratio measurements using a multicollector inductively coupled plasma mass spectrometer combined with an isotope dilution technique. The 28Si-enriched crystal was dissolved in tetramethylammonium hydroxide and three different blended solutions were used to correct for mass bias in the measurement. The molar mass of the 28Si-enriched crystal was determined to be 27.976 970 09 g mol-1 with a standard uncertainty of 0.000 000 14 g mol-1. This corresponds to a relative standard uncertainty of 5.2 × 10-9. This result is consistent with measurements reported by the Physikalisch-Technische Bundesanstalt, Germany.

  3. Cross sections for ionization of tetrahydrofuran by protons at energies between 300 and 3000 keV

    NASA Astrophysics Data System (ADS)

    Wang, Mingjie; Rudek, Benedikt; Bennett, Daniel; de Vera, Pablo; Bug, Marion; Buhr, Ticia; Baek, Woon Yong; Hilgers, Gerhard; Rabus, Hans

    2016-05-01

    Double-differential cross sections for ionization of tetrahydrofuran by protons with energies from 300 to 3000 keV were measured at the Physikalisch-Technische Bundesanstalt ion accelerator facility. The electrons emitted at angles between 15∘ and 150∘ relative to the ion-beam direction were detected with an electrostatic hemispherical electron spectrometer. Single-differential and total ionization cross sections have been derived by integration. The experimental results are compared to the semiempirical Hansen-Kocbach-Stolterfoht model as well as to the recently reported method based on the dielectric formalism. The comparison to the latter showed good agreement with experimental data in a broad range of emission angles and energies of secondary electrons. The scaling property of ionization cross sections for tetrahydrofuran was also investigated. Compared to molecules of different size, the ionization cross sections of tetrahydrofuran were found to scale with the number of valence electrons at large impact parameters.

  4. Two highly accurate methods for pitch calibration

    NASA Astrophysics Data System (ADS)

    Kniel, K.; Härtig, F.; Osawa, S.; Sato, O.

    2009-11-01

    Among profiles, helix and tooth thickness pitch is one of the most important parameters of an involute gear measurement evaluation. In principle, coordinate measuring machines (CMM) and CNC-controlled gear measuring machines as a variant of a CMM are suited for these kinds of gear measurements. Now the Japan National Institute of Advanced Industrial Science and Technology (NMIJ/AIST) and the German national metrology institute the Physikalisch-Technische Bundesanstalt (PTB) have each developed independently highly accurate pitch calibration methods applicable to CMM or gear measuring machines. Both calibration methods are based on the so-called closure technique which allows the separation of the systematic errors of the measurement device and the errors of the gear. For the verification of both calibration methods, NMIJ/AIST and PTB performed measurements on a specially designed pitch artifact. The comparison of the results shows that both methods can be used for highly accurate calibrations of pitch standards.

  5. A new facility for the synchrotron radiation-based calibration of transfer radiation sources in the ultraviolet and vacuum ultraviolet spectral range

    NASA Astrophysics Data System (ADS)

    Thornagel, Reiner; Fliegauf, Rolf; Klein, Roman; Kroth, Simone; Paustian, Wolfgang; Richter, Mathias

    2015-01-01

    The Physikalisch-Technische Bundesanstalt (PTB) has a long tradition in the calibration of radiation sources in the ultraviolet and vacuum ultraviolet spectral range, with traceability to calculable synchrotron radiation. Within this context, new instrumentation in the PTB laboratory at the Metrology Light Source (MLS) has been put into operation that opens up extended and improved calibration possibilities. A new facility for radiation source calibrations has been set up in the spectral range from 7 nm to 400 nm based on a combined normal incidence-grazing incidence monochromator. The facility can be used for the calibration of transfer sources in terms of spectral radiant intensity or mean spectral radiance, with traceability to the MLS primary source standard. We describe the design and performance of the experimental station and give examples of some commissioning results.

  6. elecTUM: Umsetzung der eLearning-Strategie der Technischen Universität München

    NASA Astrophysics Data System (ADS)

    Rathmayer, Sabine; Gergintchev, Ivan

    An der TUM wurde ein umfassendes und integriertes eLearning-Konzept umgesetzt, welches Präsenzstudium und eLearning in allen Leistungsbereichen der Universität miteinander verzahnt. Ein besonderer Schwerpunkt lag dabei in der Schaffung einer effizienten und wettbewerbsfähigen integrierten eLearning Infrastruktur in Hinblick auf die noch weiter steigenden Studienanfängerzahlen ab dem Jahr 2011 sowie die Umsetzung von eBologna. Die Etablierung einer hochschulweiten Lernplattform stellte eine wesentliche Basis für die Umsetzung der eLearning-Strategie dar. Die wissenschaftliche und wirtschaftliche Anschlussfähigkeit im Hinblick auf eine Verwertung der Projektergebnisse wurde durch die aktive Beteiligung an einer Vielzahl hochschulübergreifender Arbeitskreise, Fachtagungen und Kooperationen, vor allem über Organisations- und Dienstleistungsmodelle sowie innovative technische Entwicklungen, sichergestellt.

  7. Absolute measurement of F2-laser power at 157 nm

    SciTech Connect

    Kueck, Stefan; Brandt, Friedhelm; Kremling, Hans-Albert; Gottwald, Alexander; Hoehl, Arne; Richter, Mathias

    2006-05-10

    We report a comparison of laser power measurements at the F2-laser wavelength oaf nm made at two facilities of the Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute. At the PTB laboratory at the electron storage ring BESSY II in Berlin, the scale for laser power was directly traced to a cryogenic radiometer operating at 157 nm, whereas at the PTB laser radiometry facility in Braunschweig the calibration of transfer detectors was performed with a newly developed standard for laser power at 157 nm, which is traceable in several steps to a cryogenic radiometer operating at 633 nm. The comparison was performed under vacuum conditions with laser pulse energies of?10 {mu}J, however with different average powers because different primary standard radiometers were used. The relative deviation for the responsivity of the transfer detector was 4.8% and thus within the combined standard uncertainty.

  8. SMARD-REXUS-18: Development and Verification of an SMA Based CubeSat Solar Panel Deployment Mechanism

    NASA Astrophysics Data System (ADS)

    Grulich, M.; Koop, A.; Ludewig, P.; Gutsmiedl, J.; Kugele, J.; Ruck, T.; Mayer, I.; Schmid, A.; Dietmann, K.

    2015-09-01

    SMARD (Shape Memory Alloy Reusable Deployment Mechanism) is an experiment for a sounding rocket developed by students at Technische Universität MUnchen (TUM). It was launched in March 2015 on REXUS 18 (Rocket Experiments for University Students). The goal of SMARD was to develop a solar panel holddown and release mechanism (HDRM) for a CubeSat using shape memory alloys (SMA) for repeatable actuation and the ability to be quickly resettable. This paper describes the technical approach as well as the technological development and design of the experiment platform, which is capable of proving the functionality of the deployment mechanism. Furthermore, the realization of the experiment as well as the results of the flight campaign are presented. Finally, the future applications of the developed HDRM and its possible further developments are discussed.

  9. Jahre Entwicklung der Instandhaltung - von der ausfallorientierten Instandhaltung zum gemeinsamen TPM und RCM

    NASA Astrophysics Data System (ADS)

    Iske, Friedhelm

    Zur Einleitung meines Beitrages möchte ich von einem Gespräch mit einem Mitarbeiter berichten, das ich als junger Vorgesetzter einer Instandhaltungsgruppe 1988 führte. Der engagierte Mitarbeiter feierte damals sein vierzigjähriges Dienstjubiläum und war stolz auf das von ihm Geleistete sowie auf den besonderen Einsatz seiner Altersgruppe, die nach dem Zweiten Weltkrieg das Werk wieder aufgebaut hatte. Auf meine Frage, was denn damals die erste Aufgabe in der Firma war, bekam ich kurz und knapp und mit einer Selbstverständlichkeit die selbstbewusste Antwort: "Unser Pferd füttern und mit dem Pferd die innerbetrieblichen Transporte erledigen“. Als junger, technisch orientierter Vorgesetzter war ich über diese Antwort sehr überrascht. Gedanklich weit entfernt war die Vorstellung, dass in der Vergangenheit Transporte mit einem Pferd erledigt wurden.

  10. Ginger: Measuring Gravitomagnetic Effects by Means of Light

    NASA Astrophysics Data System (ADS)

    Tartaglia, Angelo

    2015-01-01

    GINGER is a proposal for a new experiment aimed to the detection of the gravito-magnetic Lense-Thirring effect at the surface of the Earth. A three-dimensional set of ring lasers will be mounted on a rigid "monument". In a ring laser a light beam traveling counterclockwise is superposed to another beam traveling in the opposite sense. The anisotropy in the propagation leads to standing waves with slightly different frequencies in the two directions; the resulting beat frequency is proportional to the absolute rotation rate in space, including the gravito-magnetic drag. The experiment is planned to be built in the Gran Sasso National Laboratories in Italy and is based on an international collaboration among four Italian groups, the Technische Universität München and the University of Canterbury in Christchurch (NZ).

  11. A new facility for the synchrotron radiation-based calibration of transfer radiation sources in the ultraviolet and vacuum ultraviolet spectral range

    SciTech Connect

    Thornagel, Reiner; Fliegauf, Rolf; Klein, Roman Kroth, Simone; Paustian, Wolfgang; Richter, Mathias

    2015-01-15

    The Physikalisch-Technische Bundesanstalt (PTB) has a long tradition in the calibration of radiation sources in the ultraviolet and vacuum ultraviolet spectral range, with traceability to calculable synchrotron radiation. Within this context, new instrumentation in the PTB laboratory at the Metrology Light Source (MLS) has been put into operation that opens up extended and improved calibration possibilities. A new facility for radiation source calibrations has been set up in the spectral range from 7 nm to 400 nm based on a combined normal incidence-grazing incidence monochromator. The facility can be used for the calibration of transfer sources in terms of spectral radiant intensity or mean spectral radiance, with traceability to the MLS primary source standard. We describe the design and performance of the experimental station and give examples of some commissioning results.

  12. Reduction of the uncertainty of the PTB vacuum pressure scale by a new large area non-rotating piston gauge

    NASA Astrophysics Data System (ADS)

    Bock, Th; Ahrendt, H.; Jousten, K.

    2009-10-01

    This paper describes the metrological characterization of a new large area piston gauge (FRS5, Furness Rosenberg Standard) installed at the vacuum metrology laboratory of the Physikalisch-Technische Bundesanstalt (PTB). The operational procedure and the uncertainty budget for pressures between 30 Pa and 11 kPa are given. Comparisons between the FRS5 and a mercury manometer, a rotary piston gauge and a force-balanced piston gauge are described. We show that the reproducibility of the calibration values of capacitance diaphragm gauges is enhanced by a factor of 6 compared with a static expansion primary standard (SE2). Improvements of the SE2 performance by reducing the number of expansions and smaller uncertainties of expansion ratios are discussed.

  13. Ground Testing Of Hypervelocity Impact Effects Of Micrometeoroids And Space Debris On Solar Arrays

    NASA Astrophysics Data System (ADS)

    Schimmerohn, Martin; Rott, Martin; Gerhard, Andreas; Osterholz, Jens; Schafer, Frank; D'Accolti, Gianfelice

    2011-10-01

    Solar arrays are the satellite component most exposed to micrometeoroid and space debris (MM/SD) impacts. The damage potential of hypervelocity impacts (HVI) is characterized by considerable energy released at the impact interface leading to mechanical damage and the generation of plasma. Impact experiments performed in the past indicate that the impact plasma can induce arcing, which consequently may lead to permanent power losses as known from electrostatic discharges. An ESA study is currently ongoing, the objective of which is to study and test the susceptibility of state-of-the art solar arrays to HVI. This paper describes potential failure modes, a ground testing approach to simulate them and its implementation for the test campaign, which will be performed at Fraunhofer EMI using a light gas gun and at Technische Universität München using a plasma-dynamic accelerator. Solar array simulation equipment and comprehensive plasma diagnostics are to be applied for ground testing.

  14. Nanopositioning and nanomeasuring machine NPMM-200—a new powerful tool for large-range micro- and nanotechnology

    NASA Astrophysics Data System (ADS)

    Jäger, G.; Manske, E.; Hausotte, T.; Müller, A.; Balzer, F.

    2016-09-01

    High-precision metrology has emerged as an enabling technology for modern key technologies. Therefore, at the Technische Universität Ilmenau, a new nanopositioning and nanomeasuring machine NPMM-200 with a measuring range of 200 mm × 200 mm × 25 mm, and a resolution of 0.02 nm was developed. The machine represents the great improvement of the extended three-dimensional Abbe comparator principle to achieve nanometre accuracy. All six degrees of freedom of the mirror plate with the measuring object are measured by fibre-coupled laser interferometers, the signals of which are then used together with the probe system signals for a high-precision position and orientation control and surface and coordinate measurements. This paper presents the metrological concept, the realized design as well as the metrological parameters.

  15. Integration of a silicon-based microprobe into a gear measuring instrument for accurate measurement of micro gears

    NASA Astrophysics Data System (ADS)

    Ferreira, N.; Krah, T.; Jeong, D. C.; Metz, D.; Kniel, K.; Dietzel, A.; Büttgenbach, S.; Härtig, F.

    2014-06-01

    The integration of silicon micro probing systems into conventional gear measuring instruments (GMIs) allows fully automated measurements of external involute micro spur gears of normal modules smaller than 1 mm. This system, based on a silicon microprobe, has been developed and manufactured at the Institute for Microtechnology of the Technische Universität Braunschweig. The microprobe consists of a silicon sensor element and a stylus which is oriented perpendicularly to the sensor. The sensor is fabricated by means of silicon bulk micromachining. Its small dimensions of 6.5 mm × 6.5 mm allow compact mounting in a cartridge to facilitate the integration into a GMI. In this way, tactile measurements of 3D microstructures can be realized. To enable three-dimensional measurements with marginal forces, four Wheatstone bridges are built with diffused piezoresistors on the membrane of the sensor. On the reverse of the membrane, the stylus is glued perpendicularly to the sensor on a boss to transmit the probing forces to the sensor element during measurements. Sphere diameters smaller than 300 µm and shaft lengths of 5 mm as well as measurement forces from 10 µN enable the measurements of 3D microstructures. Such micro probing systems can be integrated into universal coordinate measuring machines and also into GMIs to extend their field of application. Practical measurements were carried out at the Physikalisch-Technische Bundesanstalt by qualifying the microprobes on a calibrated reference sphere to determine their sensitivity and their physical dimensions in volume. Following that, profile and helix measurements were carried out on a gear measurement standard with a module of 1 mm. The comparison of the measurements shows good agreement between the measurement values and the calibrated values. This result is a promising basis for the realization of smaller probe diameters for the tactile measurement of micro gears with smaller modules.

  16. A comparison between the bottom-track data of an ADCP and Laserscanning Data

    NASA Astrophysics Data System (ADS)

    Schwarzwälder, Kordula

    2015-04-01

    Simon Lutz Technische Universität München, Hydraulic and Water Resources Engineering, München, Germany Peter Rutschmann Technische Universität München, Hydraulic and Water Resources Engineering, München, Germany A standard Acoustic Doppler Current Profiler (ADCP) is constructed, as the name suggests, to gain data about the flow velocity and discharge of e.g. a river. The device is in fact similar to a sonar and uses the Doppler effect to detect the velocity of particles in the water column below the transducers. Beside that standard function it also can track the bottom of a river or sea. The pulses are scattered by the bottom and the shift in the detected velocities between bottom and bulk phase can be used to identify the surface. However this data set depends on the quality of the signal and can be influenced inter alia when the river-bed is moving. Under in situ conditions it is almost not possible to evaluate the quality of this bottom track data. On the other hand e.g. a minimum water depth is needed to get proper results with the ADCP which causes problems in a lab flume. Therefore a reservoir was used for the comparison measurement which could be drained and set nearby dry so the scanning with a RIEGL terrestrial laser scanner became feasible. Within the reservoir due to sedimentation of silt and fine sand fractions a nature-like bottom structure has developed including a talweg, steeper and more shallow areas. This is a perfect structure for the comparison of the results of these two measurement devices. With the Laser-scanning data a 3D model is generated. The bottom track cross sections of the ADCP can be implemented in this model and compared.

  17. Der neue Kosmos. Einführung in die Astronomie und Astrophysik

    NASA Astrophysics Data System (ADS)

    Unsöld, Albrecht; Baschek, Bodo

    Der neue Kosmos bietet in überschaubarem Umfang eine zusammenhängende Einführung in das Gesamtgebiet der Astronomie und Astrophysik. Aus den Bereichen: Klassische Astronomie und Planetensystem, Instrumente und Beobachtungsverfahren, Sonne und Sterne, Milchstraße und Galaxien, Kosmologie, Entstehung des Planetensystems, Entwicklung der Erde und des Lebens werden die Beobachtungsmethoden und die Ergebnisse astronomischer Forschung sowie deren theoretische Grundlagen und wechselseitigen Zusammenhänge vermittelt. Die aktualisierte 7. Auflage berücksichtigt den raschen Fortschritt astronomischer Forschung der letzten drei Jahre von unserem Planetensystem und den Entdeckungen zahlreicher Planeten bei anderen Sternen, über die fernsten Galaxien und Quasare bis zur Entwicklung der modernen Kosmologie.

  18. 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.

  19. 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.

  20. Physik des erdnahen Weltraums. Eine Einführung

    NASA Astrophysics Data System (ADS)

    Pröss, Gerd W.

    Dieses Buch, das in die Gebiete, Methoden und Ergebnisse der Extraterrestrischen Physik einführen möchte, wendet sich an ein relativ breites Publikum. Vorausgesetzt werden lediglich Grundkenntnisse der Mathematik und Physik, wie sie in den ersten Semestern eines natur- oder ingenieurwissenschaftlichen Studiums erworben werden. Spezielleres Wissen wird im Zusammenhang mit dem jeweils betrachteten Phänomen abgeleitet. Es eignet sich daher sowohl zum Selbststudium für Quereinsteiger als auch vorlesungsbegleitend für alle Studenten der Fachrichtungen Physik, Geophysik, Meteorologie und Astronomie. Contents: 1. Einleitung. 2. Neutrale Hochatmosphäre. 3. Absorption und Dissipation von Sonnenstrahlungsenergie. 4. Ionosphäre. 5. Magnetosphäre. 6. Interplanetares Medium. 7. Absorption und Dissipation von Sonnenwindenergie. 8. Geosphärenstürme.

  1. 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.

  2. Evaluation der zentralen TUM-Lernplattform

    NASA Astrophysics Data System (ADS)

    Schulze, Elvira; Baume, Matthias; Graf, Stephan; Gergintchev, Ivan

    Die Notwendigkeit der Qualitätssicherung und -kontrolle für innovative universitäre Lehr-/Lernszenarien ist in der Praxis unbestritten. Die Wirksamkeit der Einführung der zentralen Lernplattform CLIX Campus der imc AG an der TUM wurde mittels quantitativer und qualitativer Evaluation überprüft. Als statistische Bewertungsgrundlage wurde der Erreichungsgrad bestimmter Projektziele herangezogen. Aufbauend auf den theoretischen Grundlagen der Evaluation von Bildungsangeboten gibt diese Studie Aufschluss über die Ergebnisse der Datenerhebungen sowie die Einschätzung der Plattform aus Nutzersicht und belegt die wesentliche Bedeutung der durchgängigen IT-Infrastruktur und speziell der einheitlichen Verfügbarkeit der eLearning Angebote.

  3. Diagnose und Therapie einer Depression im höheren Lebensalter – Einflüsse von Patienten- und Arztmerkmalen

    PubMed Central

    von dem Knesebeck, Olaf; Bönte, Markus; Siegrist, Johannes; Marceau, Lisa; Link, Carol; McKinlay, John

    2013-01-01

    Zusammenfassung Studienergebnissee aus dem englischsprachigen Raum zeigen, dass diagnostische und therapeutische Entscheidungen von Hausärzten bei der Versorgung von depressiven Patienten systematischen Einflüssen unterliegen, und dass sowohl Merkmale des Arztes als auch des Patienten unabhängig vom Krankheitsbild Einfluss auf diese Entscheidungen haben. In der vorliegenden Arbeit werden Ergebnisse einer deutschen Studie präsentiert, in der die Einflüsse von Patienten- und Arztmerkmalen auf diagnostische und therapeutische ärztliche Entscheidungen bei einer Depression untersucht wurden. Unter Anwendung eines faktoriellen Experimentaldesigns spielten professionelle Schauspieler in Videofilmen die Rolle von Patienten, die Symptome für eine depressive Erkrankung äußern. In den Videofilmen, die alle auf einem identischen Skript basieren, wurden systematisch die Patientenmerkmale Alter (55 vs. 75 Jahre), Geschlecht und sozialer Status (Hausmeister vs. Lehrer) variiert. Die randomisierte Ärztestichprobe wurde nach dem Arztgeschlecht und professioneller Erfahrung (< 5 vs. > 15 Jahre) geschichtet. Der Videofilm wurde insgesamt 128 niedergelassenen Ärzten für Allgemeinmedizin und hausärztlich tätigen Internisten in ihrer Praxis vorgespielt. Danach wurden die Ärzte zu unterschiedlichen Aspekten von Diagnose und Therapie befragt. Es wurde erhoben, ob der Arzt dem Patienten über das gezeigte Gespräch hinausgehende Fragen stellen würde, welche Diagnosen er für wahrscheinlich hält, wie sicher er sich mit seiner Diagnose ist, welche diagnostischen Tests er anordnen würde, ob er den Patienten überweisen würde oder ob er Medikamente verordnen oder ihm Empfehlungen zur Änderung seines Lebensstils geben würde. Die Ergebnisse weisen darauf hin, dass sowohl die Diagnose als auch die Therapie einer Depression durch niedergelassene Hausärzte in Deutschland nur geringfügig durch die untersuchten Merkmale der Patienten und der behandelnden Ärzte beeinflusst wird

  4. Bewehrte Betonbauteile unter Betriebsbedingungen: Forschungsbericht

    NASA Astrophysics Data System (ADS)

    Eligehausen, Rolf; Kordina, Karl; Schießl, Peter

    2000-09-01

    Vorwort. Teil I: Rißbreiten (Gert König) 1 Ein mechanisches Modell zur Erhöhung der Vorhersagegenauigkeit über die Rißbreiten unter Betriebsbedingungen (Gert König und Michael Fischer). 1.1 Einleitung und Zielsetzung. 1.2 Versuchsprogramm. 1.3 Meßtechnik. 1.4 Belastung und Versuchsdurchführung. 1.5 Literatur. 2 Rißbreiten und Verformungszunahme vorgespannter Bauteile unter wiederholter Last - und Zwangbeanspruchung (Gert König und Michael Fischer). 2.1 Einleitung und Zielsetzung. 2.2 Versuchsprogramm. 2.3 Auswertung. 2.4 Ausblick. 2.5 Literatur. 3 Rißverhalten von Beton bei plötzlicher Abkühlung (Viktor Mechtcherine und Harald S. Müller). 3.1 Einleitung. 3.2 Experimentelle Untersuchungen. 3.3 Formulierung eines Stoffgesetzes für thermisch beanspruchten Beton. 3.4 Riß entwicklung in einer Betonplatte unter Temperaturschock. 3.5 Zusammenfassung. 3.6 Literatur. 4 Stahlfaserbeton unter Betriebsbedingungen bei Dauerbeanspruchung (Bo Soon Kang, Bernd Schnütgen und Friedhelm Stangenberg). 4.1 Einleitung. 4.2 Wirkung von Stahlfasern im Beton. 4.3 Versuchsprogramm. 4.4 Untersuchungen zum Verbundverhalten. 4.5 Untersuchungen zum Verhalten unter Biegebeanspruchung. 4.6 Theoretische Untersuchungen. 4.7 Literatur. 5 Experimentelle Untersuchungen an Stahlbeton-Zugkörpern unter wiederholter Belastung zur Ermittlung des versteifenden Einflusses der Mitwirkung des Betons zwischen den Rissen (Petra Seibel und Gerhard Mehlhorn). 5.1 Einleitung. 5.2 Ansatz zur Bestimmung der Mitwirkung des Betons zwischen den Rissen nach Eurocode 2, Model Code 90 und Günther. 5.3 Experimentelle Untersuchungen. 5.4 Ergebnisse. 5.5 Zusammenfassung. 5.6 Literatur. 6 Riß- und Verformungsverhalten von vorgefertigten Spannbetonträgern unter Betriebsbedingungen bei besonderer Berücksichtigung des Betonalters (Monika Maske, Heinz Meichsner und Lothar Schubert). 6.1 Einleitung. 6.2 Beschreibung der Fertigteilträger. 6.3 Belastungsversuche. 6.4 Ergebnisse. 6.5 Zusammenfassung. 6

  5. Immunotoxicity and genotoxicity testing for in-flight experiments under microgravity

    NASA Astrophysics Data System (ADS)

    Hansen, Peter-Diedrich; Hansen, Peter-Diedrich; Unruh, Eckehardt

    Life Sciences as Related to Space (F) Influence of Spaceflight Environment on Biological Systems (F44) Immunotoxicity and genotoxicity testing for In-flight experiments under microgravity Sensing approaches for ecosystem and human health Author: Peter D. Hansen Technische Universit¨t Berlin, Faculty VI - Planen, Bauen, Umwelt, a Institute for Ecological Research and Technology, Department for Ecotoxicology, Berlin, Germany Peter-diedrich.hansen@tu-berlin.de Eckehardt Unruh Technische Universit¨t Berlin, Faculty VI - Planen, Bauen, Umwelt, Institute a for Ecological Research and Technology, Department for Ecotoxicology, Berlin, Germany An immune response by mussel hemocytes is the selective reaction to particles which are identified as foreign by its immune system shown by phagocytosis. Phagocytotic activity is based on the chemotaxis and adhesion, ingestion and phagosome formation. The attachment at the surface of the hemocytes and consequently the uptake of the particles or bacteria can be directly quantified in the format of a fluorescent assay. Another relevant endpoint of phagocytosis is oxidative burst measured by luminescence. Phagocytosis-related production of ROS will be stimulated with opsonised zymosan. The hemocytes will be stored frozen at -80oC and reconstituted in-flight for the experiment. The assay system of the TRIPLELUX-B Experiment has been performed with a well-defined quantification and evaluation of the immune function phagocytosis. The indicator cells are the hemocytes of blue mussels (Mytilus edulis). The signals of the immuno cellular responses are translated into luminescence as a rapid optical reporter system. The results expected will determine whether the observed responses are caused by microgravity and/or radiation (change in permeability, endpoints in genotoxicity: DNA unwinding). The samples for genotoxicity will be processed after returning to earth. The immune system of invertebrates has not been studied so far in space. The

  6. Sonification of acoustic emission data

    NASA Astrophysics Data System (ADS)

    Raith, Manuel; Große, Christian

    2014-05-01

    purposes (students, co-workers). On goal is to establish a real-time frequency transformation into the audio range to avoid time consuming visual data processing during the experiments. It is also the intention to analyze the signals using psycho-acoustic methods with the help of specialists from electrical engineering. Reference: Raith, Manuel (2013). "Schallemissionsanalyse bei Pulloutexperimenten an Verbunddübeln" Masterarbeit. Technische Universität München, Lehrstuhl für Zerstörungsfreie Prüfung. Malm, Fabian (2012). "Schallemissionsanalyse am humanen Femur" Masterarbeit. Technische Universität München, Lehrstuhl für Zerstörungsfreie Prüfung. Richter R. (2009): Einsatz der Schallemissionsanalyse zur Detektion des Riss und Abplatzungsverhaltens von Beton unter Brandeinwirkung. Diplomarbeit. Materialprüfungsanstalt Universität Stuttgart Keywords: Acoustic emission, bonded anchors, femur, pullout test, fire-spalling

  7. ESPACE - a geodetic Master's program for the education of Satellite Application Engineers

    NASA Astrophysics Data System (ADS)

    Hedman, K.; Kirschner, S.; Seitz, F.

    2012-04-01

    In the last decades there has been a rapid development of new geodetic and other Earth observation satellites. Applications of these satellites such as car navigation systems, weather predictions, and, digital maps (such as Google Earth or Google Maps) play a more and more important role in our daily life. For geosciences, satellite applications such as remote sensing and precise positioning/navigation have turned out to be extremely useful and are meanwhile indispensable. Today, researchers within geodesy, climatology, oceanography, meteorology as well as within Earth system science are all dependent on up-to-date satellite data. Design, development and handling of these missions require experts with knowledge not only in space engineering, but also in the specific applications. That gives rise to a new kind of engineers - satellite application engineers. The study program for these engineers combines parts of different classical disciplines such as geodesy, aerospace engineering or electronic engineering. The satellite application engineering program Earth Oriented Space Science and Technology (ESPACE) was founded in 2005 at the Technische Universität München, mainly from institutions involved in geodesy and aerospace engineering. It is an international, interdisciplinary Master's program, and is open to students with a BSc in both Science (e.g. Geodesy, Mathematics, Informatics, Geophysics) and Engineering (e.g. Aerospace, Electronical and Mechanical Engineering). The program is completely conducted in English. ESPACE benefits from and utilizes its location in Munich with its unique concentration of expertise related to space science and technology. Teaching staff from 3 universities (Technische Universität München, Ludwig-Maximilian University, University of the Federal Armed Forces), research institutions (such as the German Aerospace Center, DLR and the German Geodetic Research Institute, DGFI) and space industry (such as EADS or Kayser-Threde) are

  8. Extreme-ultraviolet collector mirror measurement using large reflectometer at NewSUBARU synchrotron facility

    NASA Astrophysics Data System (ADS)

    Iguchi, Haruki; Hashimoto, Hiraku; Kuki, Masaki; Harada, Tetsuo; Kinoshita, Hiroo; Watanabe, Takeo; Platonov, Yuriy Y.; Kriese, Michael D.; Rodriguez, Jim R.

    2016-06-01

    In extreme-ultraviolet (EUV) lithography, the development of high-power EUV sources is one of the critical issues. The EUV output power directly depends on the collector mirror performance. Furthermore, mirrors with large diameters are necessary to achieve high collecting performance and take sufficient distance to prevent heat and debris from a radiation point of the source. Thus collector mirror development with accurate reflectometer is important. We have developed a large reflectometer at BL-10 beamline of the NewSUBARU synchrotron facility that can be used for mirrors with diameters, thicknesses, and weights of up to 800 mm, 250 mm, and 50 kg, respectively. This reflectometer can measure reflectivity with fully s-polarized EUV light. In this study, we measured the reflectance of a 412-mm-diameter EUV collector mirror using a maximum incident angle of 36°. We obtained the peak reflectance, center wavelength and reflection bandwidth results and compared our results with Physikalisch-Technische Bundesanstalt results.

  9. Time-resolved fast-neutron radiography of air-water two-phase flows in a rectangular channel by an improved detection system

    NASA Astrophysics Data System (ADS)

    Zboray, Robert; Dangendorf, Volker; Mor, Ilan; Bromberger, Benjamin; Tittelmeier, Kai

    2015-07-01

    In a previous work, we have demonstrated the feasibility of high-frame-rate, fast-neutron radiography of generic air-water two-phase flows in a 1.5 cm thick, rectangular flow channel. The experiments have been carried out at the high-intensity, white-beam facility of the Physikalisch-Technische Bundesanstalt, Germany, using an multi-frame, time-resolved detector developed for fast neutron resonance radiography. The results were however not fully optimal and therefore we have decided to modify the detector and optimize it for the given application, which is described in the present work. Furthermore, we managed to improve the image post-processing methodology and the noise suppression. Using the tailored detector and the improved post-processing, significant increase in the image quality and an order of magnitude lower exposure times, down to 3.33 ms, have been achieved with minimized motion artifacts. Similar to the previous study, different two-phase flow regimes such as bubbly slug and churn flows have been examined. The enhanced imaging quality enables an improved prediction of two-phase flow parameters like the instantaneous volumetric gas fraction, bubble size, and bubble velocities. Instantaneous velocity fields around the gas enclosures can also be more robustly predicted using optical flow methods as previously.

  10. Time-resolved fast-neutron radiography of air-water two-phase flows in a rectangular channel by an improved detection system.

    PubMed

    Zboray, Robert; Dangendorf, Volker; Mor, Ilan; Bromberger, Benjamin; Tittelmeier, Kai

    2015-07-01

    In a previous work, we have demonstrated the feasibility of high-frame-rate, fast-neutron radiography of generic air-water two-phase flows in a 1.5 cm thick, rectangular flow channel. The experiments have been carried out at the high-intensity, white-beam facility of the Physikalisch-Technische Bundesanstalt, Germany, using an multi-frame, time-resolved detector developed for fast neutron resonance radiography. The results were however not fully optimal and therefore we have decided to modify the detector and optimize it for the given application, which is described in the present work. Furthermore, we managed to improve the image post-processing methodology and the noise suppression. Using the tailored detector and the improved post-processing, significant increase in the image quality and an order of magnitude lower exposure times, down to 3.33 ms, have been achieved with minimized motion artifacts. Similar to the previous study, different two-phase flow regimes such as bubbly slug and churn flows have been examined. The enhanced imaging quality enables an improved prediction of two-phase flow parameters like the instantaneous volumetric gas fraction, bubble size, and bubble velocities. Instantaneous velocity fields around the gas enclosures can also be more robustly predicted using optical flow methods as previously. PMID:26233413

  11. Time-resolved Fast Neutron Radiography of Air-water Two-phase Flows

    NASA Astrophysics Data System (ADS)

    Zboray, Robert; Dangendorf, Volker; Mor, Ilan; Tittelmeier, Kai; Bromberger, Benjamin; Prasser, Horst-Michael

    Neutron imaging, in general, is a useful technique for visualizing low-Z materials (such as water or plastics) obscured by high-Z materials. However, when significant amounts of both materials are present and full-bodied samples have to be examined, cold and thermal neutrons rapidly reach their applicability limit as the samples become opaque. In such cases one can benefit from the high penetrating power of fast neutrons. In this work we demonstrate the feasibility of time-resolved, fast neutron radiography of generic air-water two-phase flows in a 1.5 cm thick flow channel with Aluminum walls and rectangular cross section. The experiments have been carried out at the high-intensity, white-beam facility of the Physikalisch-Technische Bundesanstalt, Germany. Exposure times down to 3.33 ms have been achieved at reasonable image quality and acceptable motion artifacts. Different two-phase flow regimes such as bubbly slug and churn flows have been examined. Two-phase flow parameters like the volumetric gas fraction, bubble size and bubble velocities have been measured.

  12. Concepts for VLBI Station Control as Part of NEXPReS

    NASA Astrophysics Data System (ADS)

    Ettl, M.; Neidhardt, A.; Schönberger, M.; Alef, W.; Himwich, E.; Beaudoin, C.; Plötz, C.; Lovell, J.; Hase, H.

    2012-12-01

    In the Novel EXploration Pushing Robust e-VLBI Services-project (NEXPReS) the Technische Universität München (TUM) realizes concepts for continuous quality monitoring and station remote control in cooperation with the Max-Planck-Institute for Radio Astronomy, Bonn. NEXPReS is a three-year project, funded within the European Seventh Framework program. It is aimed to develop e-VLBI services for the European VLBI Network (EVN), which can also support the IVS observations (VLBI2010). Within this project, the TUM focuses on developments of an operational remote control system (e-RemoteCtrl) with authentication and authorization. It includes an appropriate role management with different remote access states for future observation strategies. To allow a flexible control of different systems in parallel, sophisticated graphical user interfaces are designed and realized. The software is currently under test in the new AuScope network, Australia/New Zealand. Additional system parameters and information are collected with a new system monitoring (SysMon) for a higher degree of automation, which is currently under preparation for standardization within the IVS Monitoring and Control Infrastructure (MCI) Collaboration Group. The whole system for monitoring and control is fully compatible with the NASA Field System and extends it.

  13. Calorimetric determination of kQ factors for NE 2561 and NE 2571 ionization chambers in 5 cm × 5 cm and 10 cm × 10 cm radiotherapy beams of 8 MV and 16 MV photons

    NASA Astrophysics Data System (ADS)

    Krauss, Achim; Kapsch, Ralf-Peter

    2007-10-01

    The relative uncertainty of the ionometric determination of the absorbed dose to water, Dw, in the reference dosimetry of high-energy photon beams is in the order of 1.5% and is dominated by the uncertainty of the calculated chamber- and energy-dependent correction factors kQ. In the present investigation, kQ values were determined experimentally in 5 cm × 5 cm and 10 cm × 10 cm radiotherapy beams of 8 MV and 16 MV bremsstrahlung by means of a water calorimeter operated at 4 °C. Ionization chambers of the types NE 2561 and NE 2571 were calibrated directly in the water phantom of the calorimeter. The measurements were carried out at the linear accelerator of the Physikalisch-Technische Bundesanstalt. It is shown that the kQ factor of a single ionization chamber can be measured with a standard uncertainty of less than 0.3%. No significant variations of kQ were found for the different lateral sizes of the radiation fields used in this investigation.

  14. Concepts for continuous quality monitoring and station remote control

    NASA Astrophysics Data System (ADS)

    Ettl, M.; Neidhardt, A.; Rottmann, H.; Mühlbauer, M.; Plötz, C.; Himwich, E.; Beaudoin, C.; Szomoru, A.

    2011-07-01

    In the newly funded "Novel EXploration Pushing Robuste-VLBI Services", - project (NEXPReS) the Technische Universitaet Muenchen realize concepts for continuous quality monitoring and station remote control in cooperation with the Max-Planck-Institute for Radioastronomy, Bonn. NEXPReS is a three-year project aimed at further developing e-VLBI services of the European VLBI Network (EVN), with the goal of incorporating e-VLBI into every astronomical observation conducted by the EVN. This project focus on developments of an operational e-control system with authentication and authorization. It includes an appropriate role management with different remote access states for future observation strategies. To allow a flexible control of different systems in parallel sophisticated graphical user interfaces are designed and realized. It requires also a session oriented data management. Because of the higher degree of automation additional system parameters and information is collected with a new system monitoring. The whole system for monitoring and control is fully compatible to the NASA field system as extension. The concept will be proofed with regular tests between Wettzell and Effelsberg.

  15. Environment Characterisation by Using Innovative Debris Detector

    NASA Astrophysics Data System (ADS)

    Bauer, W.; Barschke, M.; Romberg, O.

    The knowledge about small (> 100 µm) but abundant objects in space is low. To analyze the quantity of space debris and micrometeoroids in space, an innovative in-situ impact detection method has been developed at the German Aerospace Center (DLR) in Bremen, Germany. The Solar generator based Impact Detector, SOLID, uses solar panels for impact detection. Since solar panels provide large detection areas, this method allows the collection of large amounts of data. Such data enhances space debris and micrometeoroid population datasets and permits for related model validation. A ground verification of the detection method has been performed by Hypervelocity Impact (HVI) tests at Fraunhofeŕs Ernst-Mach-Institut (EMI), Freiburg, Germany. The objective of this investigation was to test the applicability of the developed method concerning in-situ detection of space debris and micrometeoroids. The achieved test results are in agreement with ESA developed damage equations and the functionality of the detector has clearly been demonstrated. This paper presents the already manufactured hardware planned for on orbit test on the Technische Universität Berlin's TechnoSat mission in early 2016. The expected impact frequencies at corresponding probabilities and uncertainties regarding object size estimation are also outlined.

  16. The Second Mössbauer Effect

    NASA Astrophysics Data System (ADS)

    Kienle, Paul

    "The Second Mössbauer Effect" was the headline of the "Spiegel" (a German weekly journal like the "Times") from May 13, 1964 for announcing the foundation of the "Physik-Department" at the Technische Hochschule München (THM), as it was still called at this time. Maier-Leibnitz was irritated by this headline because the article did not mention at all his contribution to the consolidation of the structure of the three physics institutes (Experimental, Technical, and Theoretical Physics) in the beginning of the sixties. Already in the late fifties ML's Institute for Technical Physics was overloaded with students working on their diploma or doctoral theses, because research in the new field of applied nuclear physics was very attractive and ML had for each student who applied an interesting research project. In the average, ML had to supervise between 150-200 diploma students, an impossible task. So, young postdoctoral students had to help him out by taking over the duties of professors. In a letter to the Bavarian Ministry of Education and Arts in 1957 he complained: "The directors of the institutes are hopelessly surcharged and the institutes are overcrowded, the resources for research projects are totally insufficient and lots of time and energy is wasted for finding additional resources."

  17. Low-cost approach of a 3D display for general aviation aircraft

    NASA Astrophysics Data System (ADS)

    Sachs, Gottfried; Sperl, Roman; Karl, Wunibald

    2001-08-01

    A low cost 3D-display and navigation system is described which presents guidance information in a 3-dimensional format to the pilot. For achieving the low cost goal, Commercial-off-the-Shelf components are used. The visual information provided by the 3D-display includes a presentation of the future flight path and other guidance elements as well as an image of the outside world. For generating the displayed information, a PC will be used. An appropriate computer software is available to generate the displayed information in real-time with an adequately high update rate. Precision navigation data which is required for accurately adjusting the displayed guidance information are provided by an integrated low cost navigation system. This navigation system consists of a differential global positioning system and an inertial measurement unit. Data from the navigation system is fed into an onboard-computer, using terrain elevation and feature analysis data to generate a synthetic image of the outside world. The system is intended to contribute to the safety of General Aviation aircraft, providing an affordable guidance and navigation aid for this type of aircraft. The low cost 3D display and navigation system will be installed in a two-seat Grob 109B aircraft which is operated by the Institute of Flight Mechanics and Flight Control of the Technische Universitchen as a research vehicle.

  18. First set of gated x-ray imaging diagnostics for the Laser Megajoule facility

    NASA Astrophysics Data System (ADS)

    Rosch, R.; Trosseille, C.; Caillaud, T.; Allouche, V.; Bourgade, J. L.; Briat, M.; Brunel, P.; Burillo, M.; Casner, A.; Depierreux, S.; Gontier, D.; Jadaud, J. P.; Le Breton, J. P.; Llavador, P.; Loupias, B.; Miquel, J. L.; Oudot, G.; Perez, S.; Raimbourg, J.; Rousseau, A.; Rousseaux, C.; Rubbelynck, C.; Stemmler, P.; Troussel, P.; Ulmer, J. L.; Wrobel, R.; Beauvais, P.; Pallet, M.; Prevot, V.

    2016-03-01

    The Laser Megajoule (LMJ) facility located at CEA/CESTA started to operate in the early 2014 with two quadruplets (20 kJ at 351 nm) focused on target for the first experimental campaign. We present here the first set of gated x-ray imaging (GXI) diagnostics implemented on LMJ since mid-2014. This set consists of two imaging diagnostics with spatial, temporal, and broadband spectral resolution. These diagnostics will give basic measurements, during the entire life of the facility, such as position, structure, and balance of beams, but they will also be used to characterize gas filled target implosion symmetry and timing, to study x-ray radiography and hydrodynamic instabilities. The design requires a vulnerability approach, because components will operate in a harsh environment induced by neutron fluxes, gamma rays, debris, and shrapnel. Grazing incidence x-ray microscopes are fielded as far as possible away from the target to minimize potential damage and signal noise due to these sources. These imaging diagnostics incorporate microscopes with large source-to-optic distance and large size gated microchannel plate detectors. Microscopes include optics with grazing incidence mirrors, pinholes, and refractive lenses. Spatial, temporal, and spectral performances have been measured on x-ray tubes and UV lasers at CEA-DIF and at Physikalisch-Technische Bundesanstalt BESSY II synchrotron prior to be set on LMJ. GXI-1 and GXI-2 designs, metrology, and first experiments on LMJ are presented here.

  19. Electromagnetic DM technology meets future AO demands

    NASA Astrophysics Data System (ADS)

    Hamelinck, Roger; Rosielle, Nick; Steinbuch, Maarten; Doelman, Niek

    New deformable mirror technology is developed by the Technische Universiteit Eindhoven, Delft University of Technology and TNO Science and Industry. Several prototype adaptive deformable mirrors are realized mirrors, up to 427 actuators and ∅150mm diameter, with characteristics suitable for future AO systems. The prototypes consist of a 100µm thick, continuous facesheet on which low voltage, electromagnetic, push-pull actuators impose out-of-plane displacements. The variable reluctance actuators with ±10µm stroke and nanometer resolution are located in a standard actuator module. Each module with 61 actuators connects to a single PCB with dedicated, 16 bit, PWM based, drivers. A LVDS multi-drop cable connects up to 32 actuator modules. With the actuator module, accompanying PCB and multi-drop system the deformable mirror technology is made modular in its mechanics and electronics. An Ethernet-LVDS bridge enables any commercial PC to control the mirror using the UDP standard. Latest results of the deformable mirror technology development are presented.

  20. Time-resolved fast-neutron radiography of air-water two-phase flows in a rectangular channel by an improved detection system

    SciTech Connect

    Zboray, Robert; Dangendorf, Volker; Bromberger, Benjamin; Tittelmeier, Kai; Mor, Ilan

    2015-07-15

    In a previous work, we have demonstrated the feasibility of high-frame-rate, fast-neutron radiography of generic air-water two-phase flows in a 1.5 cm thick, rectangular flow channel. The experiments have been carried out at the high-intensity, white-beam facility of the Physikalisch-Technische Bundesanstalt, Germany, using an multi-frame, time-resolved detector developed for fast neutron resonance radiography. The results were however not fully optimal and therefore we have decided to modify the detector and optimize it for the given application, which is described in the present work. Furthermore, we managed to improve the image post-processing methodology and the noise suppression. Using the tailored detector and the improved post-processing, significant increase in the image quality and an order of magnitude lower exposure times, down to 3.33 ms, have been achieved with minimized motion artifacts. Similar to the previous study, different two-phase flow regimes such as bubbly slug and churn flows have been examined. The enhanced imaging quality enables an improved prediction of two-phase flow parameters like the instantaneous volumetric gas fraction, bubble size, and bubble velocities. Instantaneous velocity fields around the gas enclosures can also be more robustly predicted using optical flow methods as previously.

  1. Analysis of terrain data based on satellite imagery for aviation purposes

    NASA Astrophysics Data System (ADS)

    Eilmus, B.; Heidelmeyer, G.; Klingauf, U.

    2007-10-01

    Due to the regulation of the ICAO (International Civil Aviation Organization), which requires the provision of electronic terrain data with a certain quality by each contracting state for its territory, the demand for terrain data for aviation purposes increases. This regulation poses a problem particularly for developing and newly industrialising countries, which have not the financial resources for the generation of terrain data meeting the required specifications. Studies performed at the Institute of Flight Systems and Automatic Control at the Technische Universitaet Darmstadt show that a promising and cost-effective method to encounter this challenge is the use of high resolution optical satellite imagery with a stereoscopic coverage. This method can be performed without the acquisition of ground control points and leads by this to cost reductions. To validate this method, the accuracy of terrain data generated from satellite imagery is analysed. Due to the various available very high resolution satellites, the accuracy is not limited by the spatial resolution of the imagery, but principally by the accuracy of the geolocation. This is why furthermore methods are proposed that may help to increase the accuracy, to eliminate blunders as well as systematic errors and thus to enhance the reliability of the acquired terrain information in order to achieve applicability in aviation.

  2. Die zwei Kulturen

    NASA Astrophysics Data System (ADS)

    Ankolekar, Anupriya; Krötzsch, Markus; Tran, Than; Vrandecic, Denny

    Oft werden zwei mögliche Entwicklungen des Webs diskutiert - das Web 2.0 und das Semantic Web. Wenn wir diese zwei Visionen für das zukünftige Web unter die Lupe nehmen, dann lässt sich feststellen, dass sich die Ideen in ihrem Kern und ihren Technologien gegenseitig ergänzen. Dementsprechend können und sollen beide Visionen von den Erfahrungen und Stärken der anderen profitieren. Wir glauben daran, dass zukünftige Webanwendungen den Web 2.0-Fokus auf Community und Benutzerfreundlichkeit beibehalten und, darüber hinaus, auch von Technologien des Semantic Web zur Vereinfachung der mashupähnlichen Datenintegration profitieren werden. Auf Basis eines Semantic Blog-Szenarios werden wir hier die Vorteile einer möglichen Kombination von Semantic Web und Web 2.0 illustrieren, die zeitnah realisiert werden kann. Wir werden auch auf technische Probleme eingehen, die bei der Erweiterung dieses Szenarios entstehen. Wir stellen dar, wie aktuelle Entwicklungen in der Semantic Web Forschung diese Probleme angehen können, und setzen zugleich auch Schwerpunkte für die zukünftige Forschung, die in diesem Zusammenhang relevant sind.

  3. 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].

  4. Safe and secure remote control for the Twin Radio Telescope Wettzell

    NASA Astrophysics Data System (ADS)

    Neidhardt, A.; Ettl, M.; Mühlbauer, M.; Kronschnabl, G.; Alef, W.; Himwich, E.; Beaudoin, C.; Plötz, C.; Lovell, J.

    2013-08-01

    More VLBI stations, more experiments, more data and a faster analysis for a real-time monitoring of earth parameters and reference frames are the goals of the future VLBI2010 network. One key technology is e-VLBI. But also the control might follow to adapt and to manage these new challenges. Therefore the Technische Universität München (TUM), Germany realizes concepts for continuous quality monitoring and station remote control in cooperation with the Max Planck Institute for Radio Astronomy, Germany. The development is funded by the European Seventh Framework program in the three year project “Novel EXploration Pushing Robust e-VLBI Services (NEXPReS)” of the European VLBI Network (EVN). Within this project, the TUM focuses on developments for a safe, secure and reliable remote control (e-RemoteCtrl) of the NASA Field System with authentication, authorization and user roles to operate and automate radio telescopes, like the new Twin Radio Telescope Wettzell (TTW) at the Geodetic Observatory Wettzell, Germany. One of these telescopes will become operative this year, so that this is a first real-life test for the new control software and realizations.

  5. KEY COMPARISON: Final report for CCQM-K17: pH determination on a phthalate buffer by Harned cell measurements

    NASA Astrophysics Data System (ADS)

    Spitzer, Petra; Hongyu, Xiu; Dazhou, Chen; Famnin, Men; Bjame Kristensen, Hans; Hjelmer, Bettina; Nakamura, Susumu; Hwang, Euijin; Lee, Hwashim; Castro, Esther; Monroy Mendoza, Marcela; Kozlowski, Wladyslaw; Wyszynska, Joanna; Mateuszuk, A.; Pawlina, Monika; Karpov, Oleg V.; Zdorikov, Nicolaj; Seyku, Elena; Maximov, Igor; Vyskocil, Leos; Máriássy, Michal; Pratt, Kenneth W.; Vospelova, Alena; Giera, Janine; Eberhard, Ralf

    2003-01-01

    The second key comparison for the quantity pH, CCQM-K17, was carried out to assess the degree of equivalence of the national primary measurement procedures used to determine the pH of primary standard buffer solutions. The CCQM-K17 comparison allows estimations of the capability of ten national metrology institutes (NMIs) to determine the pH of a phthalate buffer of unknown concentration at different temperatures. The key comparison was co-ordinated by the CCQM Working Group on Electrochemical Analysis and piloted by the Physikalisch-Technische Bundesanstalt (PTB) with assistance from the National Institute of Standards and Technology (NIST) and the Slovak Institute of Metrology (SMU). The measurement results of the NMIs agreed not at the same level as for the first key comparison on pH CCQM-K9. The results obtained by seven of the eleven participants agree very well within the uncertainty stated by the participants. Four participants obtained results somewhat lower. The two groups of results are most obviously evident at a measurement temperature of 37 °C. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the Mutual Recognition Arrangement (MRA).

  6. A novel instrument for quantitative nanoanalytics involving complementary X-ray methodologies

    SciTech Connect

    Lubeck, J.; Beckhoff, B.; Fliegauf, R.; Holfelder, I.; Hoenicke, P.; Mueller, M.; Pollakowski, B.; Reinhardt, F.; Weser, J.

    2013-04-15

    A novel ultra-high vacuum instrument for X-ray reflectometry and spectrometry-related techniques for nanoanalytics by means of synchrotron radiation has been constructed and commissioned. This versatile instrument was developed by the Physikalisch-Technische Bundesanstalt, Germany's national metrology institute, and includes a 9-axis manipulator that allows for an independent alignment of the samples with respect to all degrees of freedom. In addition, a rotational and translational movement of several photodiodes as well as a translational movement of an aperture system in and out of the beam is provided. Thus, the new instrument enables various analytical techniques based on energy dispersive X-ray detectors such as reference-free X-ray fluorescence analysis (XRF), total-reflection XRF, grazing-incidence XRF in addition to optional X-ray reflectometry measurements or polarization-dependent X-ray absorption fine structure analyses. With this instrument samples having a size of up to 100 mm Multiplication-Sign 100 mm can be analyzed with respect to their mass deposition, elemental or spatial composition, or the species in order to probe surface contamination, layer composition and thickness, the depth profile of matrix elements or implants, the species of nanolayers, nanoparticles or buried interfaces as well as the molecular orientation of bonds. Selected applications of this advanced ultra-high vacuum instrument demonstrate both its flexibility and capability.

  7. Surviving the Glut: The Management of Event Streams in Cyberphysical Systems

    NASA Astrophysics Data System (ADS)

    Buchmann, Alejandro

    Alejandro Buchmann is Professor in the Department of Computer Science, Technische Universität Darmstadt, where he heads the Databases and Distributed Systems Group. He received his MS (1977) and PhD (1980) from the University of Texas at Austin. He was an Assistant/Associate Professor at the Institute for Applied Mathematics and Systems IIMAS/UNAM in Mexico, doing research on databases for CAD, geographic information systems, and objectoriented databases. At Computer Corporation of America (later Xerox Advanced Information Systems) in Cambridge, Mass., he worked in the areas of active databases and real-time databases, and at GTE Laboratories, Waltham, in the areas of distributed object systems and the integration of heterogeneous legacy systems. 1991 he returned to academia and joined T.U. Darmstadt. His current research interests are at the intersection of middleware, databases, eventbased distributed systems, ubiquitous computing, and very large distributed systems (P2P, WSN). Much of the current research is concerned with guaranteeing quality of service and reliability properties in these systems, for example, scalability, performance, transactional behaviour, consistency, and end-to-end security. Many research projects imply collaboration with industry and cover a broad spectrum of application domains. Further information can be found at http://www.dvs.tu-darmstadt.de

  8. Radiometric calibration of the in-flight blackbody calibration system of the GLORIA interferometer

    NASA Astrophysics Data System (ADS)

    Monte, C.; Gutschwager, B.; Adibekyan, A.; Kehrt, M.; Ebersoldt, A.; Olschewski, F.; Hollandt, J.

    2014-01-01

    GLORIA (Gimballed Limb Observer for Radiance Imaging of the Atmosphere) is an airborne, imaging, infrared Fourier transform spectrometer that applies the limb-imaging technique to perform trace gas and temperature measurements in the Earth's atmosphere with three-dimensional resolution. To ensure the traceability of these measurements to the International Temperature Scale and thereby to an absolute radiance scale, GLORIA carries an on-board calibration system. Basically, it consists of two identical large-area and high-emissivity infrared radiators, which can be continuously and independently operated at two adjustable temperatures in a range from -50 °C to 0 °C during flight. Here we describe the radiometric and thermometric characterization and calibration of the in-flight calibration system at the Reduced Background Calibration Facility of the Physikalisch-Technische Bundesanstalt. This was performed with a standard uncertainty of less than 110 mK. Extensive investigations of the system concerning its absolute radiation temperature and spectral radiance, its temperature homogeneity and its short- and long-term stability are discussed. The traceability chain of these measurements is presented.

  9. Slănic-Prahova low background calibration facility.

    PubMed

    Celarel, Aurelia; Duliu, O G; Bercea, S; Cenusa, C

    2016-03-01

    The reduced background of 2 nSv h(-1) of the Slănic-Prahova Low Background Radiation Laboratory allowed installing a calibration stand for low-dose-rates dosimetry. The stand is provided with (60)Co, (137)Cs and (241)Am low activity sources. A Physikalisch-Technische Bundesanstalt-calibrated AUTOMESS 6150 AD-6 dose rate meter with a 6150 AD-b/H external probe was used to check to what extent this stand could serve as a low background calibration facility. A detailed analysis of possible uncertainties in measuring dose rates evidenced an extended uncertainty related to the certified calibration as well as instrument readings of about 3 % for a confidence level of 95 %. In these conditions, the experimentally determined dose rates for all three gamma ray sources and for source-to-probe distances varying between 0.3 and 2.0 m confirmed a good correlation between the calculated and measured dose rates. At the same time, dose rates perfectly obey to an inverse squared distances law. PMID:26001826

  10. List of Participants

    NASA Astrophysics Data System (ADS)

    2008-11-01

    Mohab Abou ZeidInstitut des Hautes Études Scientifiques, Bures-sur-Yvette Ido AdamMax-Planck-Institut für Gravitationsphysik (AEI), Potsdam Henrik AdorfLeibniz Universität Hannover Mohammad Ali-AkbariIPM, Tehran Antonio Amariti Università di Milano-Bicocca Nicola Ambrosetti Université de Neuchâtel Martin Ammon Max-Planck-Institut für Physik, München Christopher AndreyÉcole Polytechnique Fédérale de Lausanne (EPFL) Laura AndrianopoliPolitecnico di Torino David AndriotLPTHE, Université UPMC Paris VI Carlo Angelantonj Università di Torino Pantelis ApostolopoulosUniversitat de les Illes Balears, Palma Gleb ArutyunovInstitute for Theoretical Physics, Utrecht University Davide AstolfiUniversità di Perugia Spyros AvramisUniversité de Neuchâtel Mirela BabalicChalmers University, Göteborg Foday BahDigicom Ioannis Bakas University of Patras Igor BandosUniversidad de Valencia Jose L F BarbonIFTE UAM/CSIC Madrid Till BargheerMax-Planck-Institut für Gravitationsphysik (AEI), Potsdam Marco Baumgartl Eidgenössische Technische Hochschule (ETH), Zürich James BedfordImperial College London Raphael BenichouLaboratoire de Physique Théorique, École Normale Supérieure, Paris Francesco Benini SISSA, Trieste Eric Bergshoeff Centre for Theoretical Physics, University of Groningen Alice BernamontiVrije Universiteit, Brussel Julia BernardLaboratoire de Physique Théorique, École Normale Supérieure, Paris Adel Bilal Laboratoire de Physique Théorique, École Normale Supérieure, Paris Marco Billo' Università di Torino Matthias Blau Université de Neuchâtel Guillaume BossardAlbert-Einstein-Institut, Golm Leonardo BriziÉcole Polytechnique Fédérale de Lausanne (EPFL) Johannes BroedelLeibniz Universität Hannover (AEI) Tom BrownQueen Mary, University of London Ilka BrunnerEidgenössische Technische Hochschule (ETH), Zürich Erling BrynjolfssonUniversity of Iceland Dmitri BykovSteklov Institute, Moscow and Trinity College, Dublin Joan CampsUniversitat de Barcelona

  11. Comparison of the NIST and PTB Air-Kerma Standards for Low-Energy X-Rays

    PubMed Central

    O’Brien, Michelle; Bueermann, Ludwig

    2009-01-01

    A comparison has been made of the air-kerma standards for low-energy x rays at the National Institute of Standards and Technology (NIST) and the Physikalisch-Technische Bundesanstalt (PTB). The comparison involved a series of measurements at the PTB and the NIST using the air-kerma standards and two NIST reference-class transfer ionization chamber standards. Results are presented for the reference radiation beam qualities in the range from 25 kV to 50 kV for low energy x rays, including the techniques used for mammography dose traceability. The tungsten generated reference radiation qualities, between 25 kV and 50 kV used for this comparison, are new to NIST; therefore this comparison will serve as the preliminary comparison for NIST and a verification of the primary standard correction factors. The mammography comparison will repeat two previously unpublished comparisons between PTB and NIST. The results show the standards to be in reasonable agreement within the standard uncertainty of the comparison of about 0.4 %.

  12. Numerical method for determining the allowable medium temperature during transient operation of a thick-walled boiler element in power plant

    NASA Astrophysics Data System (ADS)

    Rząsa, Dariusz; Duda, Piotr

    2011-12-01

    Secure and cost-effective power generation has become very important nowdays. Care must be taken while designing and operating modern steam power plants. There are regulations such as German boiler regulations (Technische Regeln für Dampfkessel 301) or European Standards that guide the user how to operate the steam power plants. However, those regulations are based on the quasi-steady state assumption and one dimensional temperature distribution in the entire element. This simplifications may not guarantee that the heating and cooling operations are conducted in the most efficient way. Thus, it was important to find an improved method that can allow to establish optimum parameters for heating and cooling operations. The optimum parameters should guarantee that the maximum total stresses in the construction element are in the allowable limits and the entire process is conducted in the shortest time. This paper summarizes mathematical descriptions how to optimize shut down process of power block devices. The optimization formulation is based on the assumption that the maximum total stresses in the whole construction element should be kept within allowable limits during cooling operation. Additionally, the operation should be processed in the shortest time possible.

  13. Determination of allowable fluid temperature during start-up operation of outlet header under the assumption of constant and temperature-dependent material properties

    NASA Astrophysics Data System (ADS)

    Rząsa, Dariusz; Duda, Piotr

    2013-09-01

    Modern supercritical power plants operate at very high temperatures and pressures. Thus the construction elements are subjected to both high thermal and mechanical loads. As a result high stresses in those components are created. In order to operate safely, it is important to monitor stresses, especially during start-up and shut-down processes. The maximum stresses in the construction elements should not exceed the allowable stresses that are defined according to boiler regulations. It is important to find optimum operating parameters, that can assure safe heating and cooling processes. The optimum parameters define temperature and pressure histories that can keep the highest stresses within allowable limit and reduce operation time as much as possible. In this paper a new numerical method for determining optimum working fluid parameters is presented. In this method, properties of steel can be assumed as constant or temperature dependent. The constant value is taken usually at the average temperature of the operation cycle. For both cases optimal parameters are determined. Based on these parameters start-up operations for both cases are conducted. During entire processes stresses in the heated element are monitored. The results obtained are compared with German boiler regulations - Technische Regeln fur Dampfkessel 301.

  14. SI-traceable determination of the spring constant of a soft cantilever using the nanonewton force facility based on electrostatic methods

    NASA Astrophysics Data System (ADS)

    Nesterov, V.; Belai, O.; Nies, D.; Buetefisch, S.; Mueller, M.; Ahbe, T.; Naparty, D.; Popadic, R.; Wolff, H.

    2016-08-01

    The PTB’s (Physikalisch-Technische Bundesanstalt, Germany) nanonewton force facility, first presented in work by Nesterov (2007 Meas. Sci. Technol. 18 360–6), Nesterov (2009 Meas. Sci. Technol. 20 084012) and Nesterov et al (2009 Metrologia 46 277–82), has been significantly improved and used to measure the stiffness of a cantilever. The facility is based on a disc pendulum with electrostatic reduction of its deflection and stiffness. In this paper, we will demonstrate that the facility is able to measure horizontal forces in the range below 1 μN with a resolution below 5 pN and an uncertainty below 2.7% for a measured force of 1 nN at a measurement duration of about 20 s. We will demonstrate the possibility of using this facility as a calibration device that can accurately determine spring constants of soft cantilevers (K ≲ 0.1 N m‑1) with traceability to the SI units. The method and the results of measuring the spring constant of a soft cantilever (K  =  0.125 N m‑1) in air, in a medium vacuum, in a high vacuum and in nitrogen are presented. We will show that a relative standard uncertainty of the spring constant calibration of better than 0.3% (measurement in a medium vacuum) and a repeatability of better than 0.04% are achieved.

  15. High-energy response of the PRESCILA and WENDI-II neutron rem meters.

    PubMed

    Olsher, Richard H; McLean, Thomas D

    2008-01-01

    WENDI-II was designed at the Los Alamos National Laboratory (LANL) specifically as a wide-range rem meter, suitable for applications at particle accelerators, with response extension to 5 GeV. PRESCILA was also designed at LANL, mainly as a lightweight alternative to traditional rem meters, but has shown excellent response characteristics above 20 MeV. This Note summarises measurements performed over a span of 4 y to characterise the high-energy neutron response (>20 MeV) of these meters to several hundred million electron volts. High-energy quasi-monoenergetic beams utilised as part of this study were produced by the cyclotron facilities at the Université Catholique de Louvain (33 and 60 MeV) and the T. Svedberg Laboratory ( 46, 95, 143 and 173 MeV). In addition, measurements were also conducted at the Los Alamos Neutron Science Center, 800 MeV spallation neutron source, in broad energy fields with an average energy of 345 MeV. For the sake of completeness, data collected between 2.5 and 19 MeV in monoenergetic neutron fields at the German Physikalisch-Technische Bundesanstalt (PTB) facility are also included in this study. PMID:18381335

  16. Remote atomic clock synchronization via satellites and optical fibers

    NASA Astrophysics Data System (ADS)

    Piester, D.; Rost, M.; Fujieda, M.; Feldmann, T.; Bauch, A.

    2011-07-01

    In the global network of institutions engaged with the realization of International Atomic Time (TAI), atomic clocks and time scales are compared by means of the Global Positioning System (GPS) and by employing telecommunication satellites for two-way satellite time and frequency transfer (TWSTFT). The frequencies of the state-of-the-art primary caesium fountain clocks can be compared at the level of 10-15 (relative, 1 day averaging) and time scales can be synchronized with an uncertainty of one nanosecond. Future improvements of worldwide clock comparisons will require also an improvement of the local signal distribution systems. For example, the future ACES (atomic clock ensemble in space) mission shall demonstrate remote time scale comparisons at the uncertainty level of 100 ps. To ensure that the ACES ground instrument will be synchronized to the local time scale at the Physikalisch-Technische Bundesanstalt (PTB) without a significant uncertainty contribution, we have developed a means for calibrated clock comparisons through optical fibers. An uncertainty below 40 ps over a distance of 2 km has been demonstrated on the campus of PTB. This technology is thus in general a promising candidate for synchronization of enhanced time transfer equipment with the local realizations of Coordinated Universal Time UTC. Based on these experiments we estimate the uncertainty level for calibrated time transfer through optical fibers over longer distances. These findings are compared with the current status and developments of satellite based time transfer systems, with a focus on the calibration techniques for operational systems.

  17. Standard conforming involute gear metrology using an articulated arm coordinate measuring system

    NASA Astrophysics Data System (ADS)

    Härtig, Frank; Lin, Hu; Kniel, Karin; Shi, Zhaoyao

    2012-10-01

    Standard conforming involute gear measurements were taken by a manually operating articulated arm system and the respective task-specific measurement uncertainties were estimated. User-friendly templates were developed to provide almost unambiguous and repeatable measurement results. They allow the metrologist to easily detect and gather the single measurement points according to existing guidelines and standards commonly used in gear metrology. The research activities were carried out at the Physikalisch-Technische Bundesanstalt (PTB), Germany in the Department of Coordinate Metrology. Measurements were taken on a robust and highly accurate large gear measurement standard of PTB, in the following called the gear standard. This gear standard materializes a left-hand and a right-hand gear as well as a spur gear. The 1 m outside diameter of the gear standard is similar to the gears used in wind power plants. A commercial articulated arm coordinate measuring system was used for the measurements. A high temperature stability of ±0.2 °C was provided to minimize thermal influences. The results of profile and helix measurements will be presented. This worldwide first investigation, on the basis of a calibrated involute gear standard, gives users of the articulating arm system quantitative information on a task-specific performance of a representative gear measurement.

  18. Supplementary comparison EURAMET.L-S24 on involute gear standards

    NASA Astrophysics Data System (ADS)

    Kniel, K.; Chanthawong, N.; Eastman, N.; Frazer, R.; Kupko, V.; Osawa, S.; Xue, Z.

    2014-01-01

    At its meeting in 2007, the EURAMET TC-Length decided to run an intercomparison of involute gear standards as a regional comparison with non-European involvement. The Physikalisch-Technische Bundesanstalt, Braunschweig und Berlin, Germany (PTB) was identified as the pilot laboratory, responsible for planning, organizing and analyzing the comparison. In all, seven participants from China, Germany, Japan, Thailand, Ukraine, United Kingdom and USA were asked to measure three different gear standards specialized for profile, helix and pitch measurements. The measurements started mid 2008 and were finished at the end of 2010. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The comparison was registered as the supplementary comparison EURAMET.L-S24. The final report has been peer-reviewed and approved for publication by the CCL WG-MRA, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  19. Organizational responses to a changing aid environment: the German Agency for Technical Cooperation (GTZ).

    PubMed

    Hill, Peter S

    2002-01-01

    As a major European donor, German government development assistance faces a series of challenges. Recent political changes have raised expectations for demonstrable health outcomes as a result of German development assistance; there has been a deepened commitment to collaboration with other bilateral and multilateral donors; and partner countries are increasingly open to new approaches to development. German development assistance also reflects a new ethos of partnership and the shift to programmatic and sector based development approaches. At the same time, its particular organizational structure and administrative framework highlight the extent of structural and systems reforms required of donors by changing development relationships, and the tensions created in responding to these. This paper examines organizational changes within the German Agency for Technical Cooperation (Deutsche Gesellschaft für Technische, Zusammenarbeit) (GTZ), aimed at increasing its Regional, Sectoral, Managerial and Process competence as they affect health and related sectors. These include the decentralization of GTZ, the trend to integration of projects, the increasing focus on policy and health systems reform, increased inter-sectoral collaboration, changes in recruitment and training, new perspectives in planning and evaluation and the introduction of a quality management programme. PMID:12298144

  20. Study of glass hydrometer calibration by hydrostatic weighting

    NASA Astrophysics Data System (ADS)

    Chen, Chaoyun; Wang, Jintao; Li, Zhihao; Zhang, Peiman

    2016-01-01

    Glass hydrometers are simple but effective instruments for measuring the density of liquids. Glass hydrometers calibration based on the Archimedes law, using silicon ring as a reference standard solid density, n-tridecane with density stability and low surface tension as the standard working liquid, based on hydrostatic weighing method designs a glass hydrometer calibration system. Glass hydrometer calibration system uses CCD image measurement system to align the scale of hydrometer and liquid surface, with positioning accuracy of 0.01 mm. Surface tension of the working liquid is measured by Whihemy plate. According to twice glass hydrometer weighing in the air and liquid can calculate the correction value of the current scale. In order to verify the validity of the principle of the hydrostatic weighing method of glass hydrometer calibration system, for measuring the density range of (770-790) kg/m3, with a resolution of 0.2 kg/m3 of hydrometer. The results of measurement compare with the Physikalisch-Technische Bundesanstalt(PTB) ,verifying the validity of the calibration system.

  1. CONCERNING THE PHASES OF THE ANNUAL VARIATIONS OF NUCLEAR DECAY RATES

    SciTech Connect

    Sturrock, P. A.; Buncher, J. B.; Fischbach, E.; Jenkins, J. H.; Mattes, J. J.; Javorsek, D. II

    2011-08-20

    Recent analyses of data sets acquired at the Brookhaven National Laboratory and at the Physikalisch-Technische Bundesanstalt both show evidence of pronounced annual variations, suggestive of a solar influence. However, the phases of decay-rate maxima do not correspond precisely to the phase of minimum Sun-Earth distance, as might then be expected. We here examine the hypothesis that decay rates are influenced by an unknown solar radiation, but that the intensity of the radiation is influenced not only by the variation in Sun-Earth distance, but also by a possible north-south asymmetry in the solar emission mechanism. We find that this can lead to phases of decay-rate maxima in the range 0-0.183 or 0.683-1 (September 6 to March 8) but that, according to this hypothesis, phases in the range of 0.183-0.683 (March 8 to September 6) are 'forbidden'. We find that phases of the three data sets analyzed here fall in the allowed range.

  2. Neutron laminography—a novel approach to three-dimensional imaging of flat objects with neutrons

    NASA Astrophysics Data System (ADS)

    Helfen, L.; Xu, F.; Schillinger, B.; Calzada, E.; Zanette, I.; Weitkamp, T.; Baumbach, T.

    2011-09-01

    Computed tomography (CT) is a three-dimensional (3D) imaging method which, for compact or prolate (i.e. rather isotropically extended around the rotation axis) specimens, can yield artefact-free reconstructed cross-sections. Laterally extended specimens like plate-like objects, however, are much less amenable to CT since reliable projection data cannot be acquired from angles where the plate is oriented parallel to the irradiation direction. To overcome this drawback, computed laminography (CL) was introduced recently to imaging set-ups at synchrotron storage rings. Here, we report on the first implementation of computed laminography with neutron radiation, showing measurements that were performed at the ANTARES neutron imaging facility at the FRM II research reactor of Technische Universität München. In general, neutrons are highly interesting probes for imaging since they provide a sensitivity to chemical elements very different from X-rays, yielding complementary information about the specimens investigated. Like for X-ray laminography, we avoid the projection directions where the beam is parallel to the long extensions of the specimen. We accomplish this by tilting of the rotation axis with respect to the transmitted-beam to an angle smaller than 90° (which would be the limiting case of CT) and roughly aligning the specimen's surface normal parallel to this rotation axis. The principles of neutron laminography are introduced and first test experiments are described.

  3. Self-triggering readout system for the neutron lifetime experiment PENeLOPE

    NASA Astrophysics Data System (ADS)

    Gaisbauer, D.; Bai, Y.; Konorov, I.; Paul, S.; Steffen, D.

    2016-02-01

    PENeLOPE is a neutron lifetime measurement developed at the Technische Universität München and located at the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) aiming to achieve a precision of 0.1 seconds. The detector for PENeLOPE consists of about 1250 Avalanche Photodiodes (APDs) with a total active area of 1225 cm2. The decay proton detector and electronics will be operated at a high electrostatic potential of -30 kV and a magnetic field of 0.6 T. This includes shaper, preamplifier, ADC and FPGA cards. In addition, the APDs will be cooled to 77 K. The 1250 APDs are divided into 14 groups of 96 channels, including spares. A 12-bit ADC digitizes the detector signals with 1 MSps. A firmware was developed for the detector including a self-triggering readout with continuous pedestal calculation and configurable signal detection. The data transmission and configuration is done via the Switched Enabling Protocol (SEP). It is a time-division multiplexing low layer protocol which provides determined latency for time critical messages, IPBus, and JTAG interfaces. The network has a n:1 topology, reducing the number of optical links.

  4. Novel control scheme for a high-speed metrological scanning probe microscope

    NASA Astrophysics Data System (ADS)

    Vorbringer-Dorozhovets, N.; Hausotte, T.; Manske, E.; Shen, J. C.; Jäger, G.

    2011-09-01

    Some time ago, an interferometer-based metrological scanning probe microscope (SPM) was developed at the Institute of Process Measurement and Sensor Technology of the Ilmenau University of Technology, Germany. The specialty of this SPM is the combined deflection detection system that comprises an interferometer and a beam deflection. Due to this system it is possible to simultaneously measure the displacement, bending and torsion of the probe (cantilever). The SPM is integrated into a nanopositioning and nanomeasuring machine (NPM machine) and allows measurements with a resolution of 0.1 nm over a range of 25 mm × 25 mm × 5 mm. Excellent results were achieved for measurements of calibrated step height and lateral standards and these results are comparable to the calibration values from the Physikalisch-Technische Bundesanstalt (PTB) (Dorozhovets N et al 2007 Proc. SPIE 6616 661624-1-7). The disadvantage was a low attainable scanning speed and accordingly large expenditure of time. Control dynamics and scanning speed are limited because of the high masses of the stage and corner mirror of the machine. For the vertical axis an additional high-speed piezoelectric drive is integrated in the SPM in order to increase the measuring dynamics. The movement of the piezoelectric drive is controlled and traceable measured by the interferometer. Hence, nonlinearity and hysteresis in the actuator do not affect the measurement. The outcome of this is an improvement of the bending control of the cantilever and much higher scan speeds of up to 200 µm s-1.

  5. Dynamic system simulation of small satellite projects

    NASA Astrophysics Data System (ADS)

    Raif, Matthias; Walter, Ulrich; Bouwmeester, Jasper

    2010-11-01

    A prerequisite to accomplish a system simulation is to have a system model holding all necessary project information in a centralized repository that can be accessed and edited by all parties involved. At the Institute of Astronautics of the Technische Universitaet Muenchen a modular approach for modeling and dynamic simulation of satellite systems has been developed called dynamic system simulation (DySyS). DySyS is based on the platform independent description language SysML to model a small satellite project with respect to the system composition and dynamic behavior. A library of specific building blocks and possible relations between these blocks have been developed. From this library a system model of the satellite of interest can be created. A mapping into a C++ simulation allows the creation of an executable system model with which simulations are performed to observe the dynamic behavior of the satellite. In this paper DySyS is used to model and simulate the dynamic behavior of small satellites, because small satellite projects can act as a precursor to demonstrate the feasibility of a system model since they are less complex compared to a large scale satellite project.

  6. Calibration of the GLAST Burst Monitor detectors

    SciTech Connect

    Kienlin, Andreas von; Bissaldi, Elisabetta; Lichti, Giselher G.; Steinle, Helmut; Diehl, Roland; Greiner, Jochen; Krumrey, Michael; Gerlach, Martin; Fishman, Gerald J.; Meegan, Charles; Kouveliotou, Chryssa; Wilson-Hodge, Colleen; Bhat, Narayana; Briggs, Michael S.; Connaughton, Valerie; Paciesas, William; Preece, Robert; Kippen, R. Marc

    2007-07-12

    The GLAST Burst Monitor (GBM) will augment the capabilities of GLAST for the detection of cosmic gamma-ray bursts by extending the energy range (20 MeV to > 300 GeV) of the Large Area Telescope (LAT) towards lower energies by 2 BGO-detectors (150 keV to 30 MeV) and 12 NaI(Tl) detectors (10 keV to 1 MeV). The physical detector response of the GBM instrument for GRBs is determined with the help of Monte Carlo simulations, which are supported and verified by on-ground calibration measurements, performed extensively with the individual detectors at the MPE in 2005. All flight and spare detectors were irradiated with calibrated radioactive sources in the laboratory (from 14 keV to 4.43 MeV). The energy/channel-relations, the dependences of energy resolution and effective areas on the energy and the angular responses were measured. Due to the low number of emission lines of radioactive sources below 100 keV, calibration measurements in the energy range from 10 keV to 60 keV were performed with the X-ray radiometry working group of the Physikalisch-Technische Bundesanstalt (PTB) at the BESSY synchrotron radiation facility, Berlin.

  7. Validation of short-pulse-laser-based measurement setup for absolute spectral irradiance responsivity calibration.

    PubMed

    Schuster, Michaela; Nevas, Saulius; Sperling, Armin

    2014-05-01

    This paper describes the validation process of mode-locked lasers in the "tunable lasers in photometry" (TULIP) setup at Physikalisch-Technische Bundesanstalt (PTB) regarding spectral irradiance responsivity calibrations. Validation has been carried out in the visible spectral range, 400-700 nm, with two different photometer heads and in the long wavelength range, 690-780 nm, with a filtered radiometer. A comparison of the results against those from two different validated measurement setups has been carried out for validation. For the visible spectral range, the comparison is conducted against the data obtained from a lamp-based monochromator setup for spectral irradiance responsivity calibrations and against the photometric values (integral quantity) measured at the photometric bench setup of PTB. For the long wavelength range, comparisons against results from two different lamp-based monochromator measurement setups were made. Additionally, the effect of different radiation bandwidths on interference oscillations has been determined for a filter radiometer without a diffuser. A procedure for the determination of the optimum bandwidth of the setup for the respective measurement device is presented. PMID:24921865

  8. World record in high speed laser surface microstructuring of polymer and steel using direct laser interference patterning

    NASA Astrophysics Data System (ADS)

    Lang, Valentin; Roch, Teja; Lasagni, Andrés. F.

    2016-03-01

    Periodic surfaces structures with micrometer or submicrometer resolution produced on the surface of components can be used to improve their mechanical, biological or optical properties. In particular, these surfaces can control the tribological performance of parts, for instance in the automotive industry. In the last years, substantial efforts have been made to develop new technologies capable to produce functionalized surfaces. One of these technologies is the Direct Laser Interference Patterning (DLIP) technology, which permits to combine high fabrication speed with high resolution even in the sub-micrometer range. In DLIP, a laser beam is split into two or more coherent beams which are guided to interfere on the work piece surface. This causes modulated laser intensities over the component's surface, enabling the direct fabrication of a periodic pattern based on selective laser ablation or melting. Depending on the angle between the laser beams and the wavelength of the laser, the pattern's spatial period can be perfectly controlled. In this study, we introduce new modular DLIP optical heads, developed at the Fraunhofer IWS and the Technische Universität Dresden for high-speed surface laser patterning of polymers and metals. For the first time it is shown that effective patterning speeds of up to 0.90 m2/min and 0.36 m2/min are possible on polymer and metals, respectively. Line- and dot-like surface architectures with spatial periods between 7 μm and 22 μm are shown.

  9. REVIEW ARTICLE: From single photons to milliwatt radiant power—electron storage rings as radiation sources with a high dynamic range

    NASA Astrophysics Data System (ADS)

    Klein, Roman; Thornagel, Reiner; Ulm, Gerhard

    2010-10-01

    The spectral radiant intensity of synchrotron radiation from electron storage rings can be calculated from basic electrodynamic relations (Schwinger equation) and it is directly proportional to the stored electron beam current, i.e. the number of stored electrons. With the necessary equipment installed to measure and control the electron beam current over a wide dynamic range, the radiant intensity of the synchrotron radiation can be adjusted accordingly without changing the spectrum. This is done, e.g., at the Metrology Light Source (MLS), the dedicated electron storage ring of the Physikalisch-Technische Bundesanstalt. The MLS is operated as a primary radiation source standard from the near IR up to the soft x-ray region and its operational parameters can be adjusted and accurately measured in a wide range: the electron beam current can be varied from 1 pA (one stored electron) up to 200 mA and thus the radiant intensity can be changed by more than 11 decades. The photon flux or radiant power for typical angular acceptances can thus be varied from single photons to milliwatts. This is a very powerful tool, e.g., for the characterization of the linearity of the response of radiation detectors or for the calibration of photon counting detectors. In this article we present an overview of past, current and possible future activities exploiting this feature.

  10. Status of the Metrology Light Source

    SciTech Connect

    Klein, R.; Ulm, G.; Feikes, J.; Hartrott, M. von; Wuestefeld, G.

    2010-06-23

    The Physikalisch-Technische Bundesanstalt (PTB), the German national metrology institute, has set up the low-energy electron storage ring Metrology Light Source (MLS) in close cooperation with the Helmholtz-Zentrum Berlin (HZB, formerly BESSY). This new storage ring has been in regular user operation since April 2008 and is dedicated to synchrotron-radiation-based metrology and technological developments in the far-IR/THz, IR, UV, VUV and EUV spectral range. The MLS has a double-bend-achromate lattice structure, injection is from a 105 MeV racetrack microtron. The electron energy can be ramped to any value from 105 MeV up to 630 MeV and the electron beam current covers the range from one stored electron (1 pA) up to 200 mA. The MLS is the first electron storage ring optimized for the generation of coherent synchrotron radiation, based on an electron bunch shortening mode. In this mode, MLS delivers coherent radiation in the far-IR/THz spectral range with enhanced intensity as compared to the normal mode of operation. Several beamlines are in operation or in construction, including one undulator beamline, bending magnet beamlines for the calibration of radiation sources and detectors and for reflectometry, an EUV metrology beamline and three IR/THz beamlines.

  11. Elektrotechnik

    NASA Astrophysics Data System (ADS)

    Schulze, A.; Schulz, P.; Lau, H.; Claußnitzer, W.; Schusterius, C.

    Die elektrische Leitfähigkeit von Metallen im Zustande höchster Reinheit und ihre Abhängigkeit von der Stromrichtung bei nicht regulären Kristallen ist ausführlich in Bd. II behandelt. Die folgende Tabelle enthält nur die technisch wichtigsten Metalle. Da Verunreinigungen, mechanische Bearbeitung und alle Störungen der kristallinen Struktur die Leitfähigkeit herabsetzen, sind die Werte der Leitfähigkeit der reinen Metalle als obere Grenzwerte anzusehen, die von technischen Metallen nicht erreicht werden. Außer der Leitfähigkeit ϰ in Ω-1cm-1 und dem spezifischen Widerstand ϱ in Ω cm oder in Ω mm2/m = 10-4Ω cm ist auch der Temperaturkoeffizient des Widerstandes zwischen 0 °C und 100 °C {α _0}^circ ;100^circ = 1/{100} bullet {β 100^circ - {β _0}^circ }/{{β _0^circ }} angegeben. Der Temperaturkoeffizient wächst mit steigender Reinheit des Metalles. Schon geringe fremde Beimengungen drücken ihn stark herab, Härtung durch mechanische Bearbeitung verkleinert ihn in geringem Maße; dagegen wird er durch Ausglühen vergrößert.

  12. High-accuracy X-ray detector calibration based on cryogenic radiometry

    NASA Astrophysics Data System (ADS)

    Krumrey, M.; Cibik, L.; Müller, P.

    2010-06-01

    Cryogenic electrical substitution radiometers (ESRs) are absolute thermal detectors, based on the equivalence of electrical power and radiant power. Their core piece is a cavity absorber, which is typically made of copper to achieve a short response time. At higher photon energies, the use of copper prevents the operation of ESRs due to increasing transmittance. A new absorber design for hard X-rays has been developed at the laboratory of the Physikalisch-Technische Bundesanstalt (PTB) at the electron storage ring BESSY II. The Monte Carlo simulation code Geant4 was applied to optimize its absorptance for photon energies of up to 60 keV. The measurement of the radiant power of monochromatized synchrotron radiation was achieved with relative standard uncertainties of less than 0.2 %, covering the entire photon energy range of three beamlines from 50 eV to 60 keV. Monochromatized synchrotron radiation of high spectral purity is used to calibrate silicon photodiodes against the ESR for photon energies up to 60 keV with relative standard uncertainties below 0.3 %. For some silicon photodiodes, the photocurrent is not linear with the incident radiant power.

  13. Non-invasive experimental determination of a CT source model.

    PubMed

    Alikhani, Babak; Büermann, Ludwig

    2016-01-01

    Non-invasive methods to determine equivalent X-ray source models of a CT scanner are presented. A high-precision technique called TRIC ("Time Resolved Integrated Charge") was developed and used to characterize the bow tie filters (BT) of the CT scanner installed at Physikalisch-Technische Bundesanstalt (PTB). Aluminum (Al) and polymethyl methacrylate (PMMA) equivalent thicknesses of the BT filters at all tube high voltages were evaluated, assuming that those consist of only one material. Thereby two different dose probes were used, a solid state detector and an ionization chamber, the former characterized by a significant and the latter by an almost negligible energy dependence of the air kerma response. A method was developed to correct for the energy dependence of the solid state dose probe. Next, a two-component material was assumed and equivalent BT filters were evaluated. The latter method was also applied using the known real BT filter materials and compared with the shape of the real BT filters. Finally, the results obtained by the TRIC method were compared with those obtained by using the so-called COBRA method ("Characterization Of Bow tie Relative Attenuation"), the latter being more suitable for measurements in a clinical environment. PMID:26602858

  14. Results for the response function determination of the Compact Neutron Spectrometer

    NASA Astrophysics Data System (ADS)

    Gagnon-Moisan, F.; Reginatto, M.; Zimbal, A.

    2012-03-01

    The Compact Neutron Spectrometer (CNS) is a Joint European Torus (JET) Enhancement Project, designed for fusion diagnostics in different plasma scenarios. The CNS is based on a liquid scintillator (BC501A) which allows good discrimination between neutron and gamma radiation. Neutron spectrometry with a BC501A spectrometer requires the use of a reliable, fully characterized detector. The determination of the response matrix was carried out at the Ion Accelerator Facility (PIAF) of the Physikalisch-Technische Bundesanstalt (PTB). This facility provides several monoenergetic beams (2.5, 8, 10, 12 and 14 MeV) and a white field (Emax ~ 17 MeV), which allows for a full characterization of the spectrometer in the region of interest (from ~ 1.5 MeV to ~ 17 MeV). The energy of the incoming neutrons was determined by the time of flight method (TOF), with time resolution in the order of 1 ns. To check the response matrix, the measured pulse height spectra were unfolded with the code MAXED and the resulting energy distributions were compared with those obtained from TOF. The CNS project required modification of the PTB BC501A spectrometer design, to replace an analog data acquisition system (NIM modules) with a digital system developed by the Ente per le Nuove tecnologie, l'Energia e l'Ambiente (ENEA). Results for the new digital system were evaluated using new software developed specifically for this project.

  15. Research on new dynamic force calibration system

    NASA Astrophysics Data System (ADS)

    Zhang, Li

    2008-06-01

    Sinusoidal force calibration method based on electrodynamic shaker and interferometric system was studied several years before at Physikalisch-Technische Bundesanstalt (PTB). In that system a load mass are screwed on the top of force transducer, the sinusoidal forces realized by accelerated load masses are traceable to acceleration and mass according to the force definition F(t) = ma(t), where m is the total mass acting on the sensing element of the force transducer and a is the time and spatial-dependent acceleration of the mass, which is directly measured by a laser interferometer. This paper will introduce a new dynamic force calibration system developed at Changcheng Institute of Metrology and Measurement (CIMM). It uses electrodynamic shakers to generate dynamic force in the range from 1N to 20kN, and heterodyne laser interferometers are used for acceleration measurement. A new air bearing system is developed to increase the performance of shakers and an active vibration isolator is used to reduce enviromental disturbance to the interferometric system.

  16. Higher-order ionosphere modeling for CODE's next reprocessing activities

    NASA Astrophysics Data System (ADS)

    Lutz, S.; Schaer, S.; Meindl, M.; Dach, R.; Steigenberger, P.

    2009-12-01

    CODE (the Center for Orbit Determination in Europe) is a joint venture between the Astronomical Institute of the University of Bern (AIUB, Bern, Switzerland), the Federal Office of Topography (swisstopo, Wabern, Switzerland), the Federal Agency for Cartography and Geodesy (BKG, Frankfurt am Main, Germany), and the Institut für Astronomische und Phsyikalische Geodäsie of the Technische Universität München (IAPG/TUM, Munich, Germany). It acts as one of the global analysis centers of the International GNSS Service (IGS) and participates in the first IGS reprocessing campaign, a full reanalysis of GPS data collected since 1994. For a future reanalyis of the IGS data it is planned to consider not only first-order but also higher-order ionosphere terms in the space geodetic observations. There are several works (e.g. Fritsche et al. 2005), which showed a significant and systematic influence of these effects on the analysis results. The development version of the Bernese Software used at CODE is expanded by the ability to assign additional (scaling) parameters to each considered higher-order ionosphere term. By this, each correction term can be switched on and off on normal-equation level and, moreover, the significance of each correction term may be verified on observation level for different ionosphere conditions.

  17. Calibration of the GLAST Burst Monitor Detectors

    SciTech Connect

    von Kienlin, Andreas; Bissaldi, Elisabetta; Lichti, Giselher G.; Steinle, Helmut; Krumrey, Michael; Gerlach, Martin; Fishman, Gerald J.; Meegan, Charles; Bhat, Narayana; Briggs, Michael S.; Diehl, Roland; Connaughton, Valerie; Greiner, Jochen; Kippen, R.Marc; Kouveliotou, Chryssa; Paciesas, William; Preece, Robert; Wilson-Hodge, Colleen

    2011-11-29

    The GLAST Burst Monitor (GBM) will augment the capabilities of GLAST for the detection of cosmic gamma-ray bursts by extending the energy range (20 MeV to > 300 GeV) of the Large Area Telescope (LAT) towards lower energies by 2 BGO-detectors (150 keV to 30 MeV) and 12 NaI(Tl) detectors (10 keV to 1 MeV). The physical detector response of the GBM instrument for GRBs is determined with the help of Monte Carlo simulations, which are supported and verified by on-ground calibration measurements, performed extensively with the individual detectors at the MPE in 2005. All flight and spare detectors were irradiated with calibrated radioactive sources in the laboratory (from 14 keV to 4.43 MeV). The energy/channel-relations, the dependences of energy resolution and effective areas on the energy and the angular responses were measured. Due to the low number of emission lines of radioactive sources below 100 keV, calibration measurements in the energy range from 10 keV to 60 keV were performed with the X-ray radiometry working group of the Physikalisch-Technische Bundesanstalt (PTB) at the BESSY synchrotron radiation facility, Berlin.

  18. Fuel Thermo-physical Characterization Project: Evaluation of Models to Calculate Thermal Diffusivity of Layered Composites

    SciTech Connect

    Burkes, Douglas; Casella, Amanda J.; Gardner, Levi D.; Casella, Andrew M.; Huber, Tanja K.; Breitkreutz, Harald

    2015-02-11

    The Office of Material Management and Minimization Fuel Thermo-physical Characterization Project at Pacific Northwest National Laboratory (PNNL) is tasked with using PNNL facilities and processes to receive irradiated low enriched uranium-molybdenum fuel plate samples and perform analyses in support of the Office of Material Management and Minimization Reactor Conversion Program. This work is in support of the Fuel Development Pillar that is managed by Idaho National Laboratory. A key portion of the scope associated with this project was to measure the thermal properties of fuel segments harvested from plates that were irradiated in the Advanced Test Reactor. Thermal diffusivity of samples prepared from the fuel segments was measured using laser flash analysis. Two models, one developed by PNNL and the other developed by the Technische Universität München (TUM), were evaluated to extract the thermal diffusivity of the uranium-molybdenum alloy from measurements made on the irradiated, layered composites. The experimental data of the “TC” irradiated fuel segment was evaluated using both models considering a three-layer and five-layer system. Both models are in acceptable agreement with one another and indicate that the zirconium diffusion barrier has a minimal impact on the overall thermal diffusivity of the monolithic U-Mo fuel.

  19. Report of pilot study CCM.P-P1 for international comparison of absolute pressure measurements in gas from 3 × 10-9 Pa to 9 × 10-4 Pa

    NASA Astrophysics Data System (ADS)

    Yoshida, Hajime; Arai, Kenta; Komatsu, Eiichi; Fujii, Kenichi; Bock, Thomas; Jousten, Karl

    2015-01-01

    A bilateral comparison of absolute gas pressure measurements from 3 × 10-9 Pa to 9 × 10-4 Pa was performed between the National Metrology Institute of Japan (NMIJ) and Physikalisch-Technische Bundesanstalt (PTB). It is a pilot study CCM.P-P1 for the next international comparison in this pressure range to test the stability of ultrahigh vacuum gauges (UHV gauges) as transfer standards. Two spinning rotor gauges (SRGs), an axial-symmetric transmission gauge (ATG), and an extractor gauge (EXG) were used as transfer standards. The calibration ratio of one SRG was sufficiently stable, but the other was not. This result indicates that improvements in the transport mechanism for SRG are needed. The two ionization gauges ATG and EXG, on the other hand, were sufficiently stable. Provisional equivalence of the pressures realized by the primary standards at NMIJ and PTB was found. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by CCM-WGS.

  20. Bilateral key comparison CCM.P-K3.1 for absolute pressure measurements from 3 × 10-6 Pa to 9 × 10-4 Pa

    NASA Astrophysics Data System (ADS)

    Fedchak, J. A.; Bock, Th; Jousten, K.

    2014-01-01

    This report describes the bilateral key comparison CCM.P-K3.1 between the National Institute of Standards and Technology (NIST) and Physikalisch-Technische Bundesanstalt (PTB) for absolute pressure in the range from 3 × 10-6 Pa to 9 × 10-4 Pa. This comparison was a follow-up to the comparison CCM.P-K3. Two ionization gauges and two spinning rotor gauges (SRGs) were used as the transfer standards for the comparison. The SRGs were used to compare the standards at a pressure of 9 × 10-4 Pa and to normalize the ionization gauge readings. The two ionization gauges were used to compare the standards in the pressure range of from 3 × 10-6 Pa to 3 × 10-4 Pa. Both laboratories used dynamic expansion chambers as standards in the comparison. The two labs showed excellent agreement with each other and with the CCM.P-K3 key comparison reference value (KCRV) over the entire range. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  1. Final report on bilateral supplementary comparison APMP.M.P-S5 in hydraulic gauge pressure from 1 MPa to 10 MPa

    NASA Astrophysics Data System (ADS)

    Yue, J.; Yang, Y.; Sabuga, W.

    2016-01-01

    This report summarizes the results of the Asia-Pacific Metrology Programme (APMP) supplementary comparison APMP.M.P-S5 for hydraulic gauge pressure in the range of 1 MPa to 10 MPa, which is a bilateral comparison carried out at the National Institute of Metrology, China (NIM) and the Physikalisch-Technische Bundesanstalt, Germany (PTB) during the period June 2014 to June 2015. NIM piloted the comparison and provided the transfer standard, which was a piston-cylinder assembly (PCA) of 1 cm2 nominal effective area built in a hydraulic pressure balance manufactured by Fluke Corporation. The laboratory standards of NIM and PTB are both hydraulic pressure balances equipped with PCAs, of which the nominal effective area is 1 cm2 for NIM and 5 cm2 for PTB. The results of the comparison successfully demonstrated that the hydraulic gauge pressure standards of NIM and PTB in the range of 1 MPa to 10 MPa are equivalent within their claimed uncertainties. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  2. Toward a standard reference database for computer-aided mammography

    NASA Astrophysics Data System (ADS)

    Oliveira, Júlia E. E.; Gueld, Mark O.; de A. Araújo, Arnaldo; Ott, Bastian; Deserno, Thomas M.

    2008-03-01

    Because of the lack of mammography databases with a large amount of codified images and identified characteristics like pathology, type of breast tissue, and abnormality, there is a problem for the development of robust systems for computer-aided diagnosis. Integrated to the Image Retrieval in Medical Applications (IRMA) project, we present an available mammography database developed from the union of: The Mammographic Image Analysis Society Digital Mammogram Database (MIAS), The Digital Database for Screening Mammography (DDSM), the Lawrence Livermore National Laboratory (LLNL), and routine images from the Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen. Using the IRMA code, standardized coding of tissue type, tumor staging, and lesion description was developed according to the American College of Radiology (ACR) tissue codes and the ACR breast imaging reporting and data system (BI-RADS). The import was done automatically using scripts for image download, file format conversion, file name, web page and information file browsing. Disregarding the resolution, this resulted in a total of 10,509 reference images, and 6,767 images are associated with an IRMA contour information feature file. In accordance to the respective license agreements, the database will be made freely available for research purposes, and may be used for image based evaluation campaigns such as the Cross Language Evaluation Forum (CLEF). We have also shown that it can be extended easily with further cases imported from a picture archiving and communication system (PACS).

  3. Diffraction efficiency of radially-profiled off-plane reflection gratings

    NASA Astrophysics Data System (ADS)

    Miles, Drew M.; Tutt, James H.; DeRoo, Casey T.; Marlowe, Hannah; Peterson, Thomas J.; McEntaffer, Randall L.; Menz, Benedikt; Burwitz, Vadim; Hartner, Gisela; Laubis, Christian; Scholze, Frank

    2015-09-01

    Future X-ray missions will require gratings with high throughput and high spectral resolution. Blazed off-plane reflection gratings are capable of meeting these demands. A blazed grating profile optimizes grating efficiency, providing higher throughput to one side of zero-order on the arc of diffraction. This paper presents efficiency measurements made in the 0.3 - 1.5 keV energy band at the Physikalisch-Technische Bundesanstalt (PTB) BESSY II facility for three holographically-ruled gratings, two of which are blazed. Each blazed grating was tested in both the Littrow configuration and anti-Littrow configuration in order to test the alignment sensitivity of these gratings with regard to throughput. This paper outlines the procedure of the grating experiment performed at BESSY II and discuss the resulting efficiency measurements across various energies. Experimental results are generally consistent with theory and demonstrate that the blaze does increase throughput to one side of zero-order. However, the total efficiency of the non-blazed, sinusoidal grating is greater than that of the blazed gratings, which suggests that the method of manufacturing these blazed profiles fails to produce facets with the desired level of precision. Finally, evidence of a successful blaze implementation from first diffraction results of prototype blazed gratings produce via a new fabrication technique at the University of Iowa are presented.

  4. Power spectrum analyses of nuclear decay rates

    NASA Astrophysics Data System (ADS)

    Javorsek, D.; Sturrock, P. A.; Lasenby, R. N.; Lasenby, A. N.; Buncher, J. B.; Fischbach, E.; Gruenwald, J. T.; Hoft, A. W.; Horan, T. J.; Jenkins, J. H.; Kerford, J. L.; Lee, R. H.; Longman, A.; Mattes, J. J.; Morreale, B. L.; Morris, D. B.; Mudry, R. N.; Newport, J. R.; O'Keefe, D.; Petrelli, M. A.; Silver, M. A.; Stewart, C. A.; Terry, B.

    2010-10-01

    We provide the results from a spectral analysis of nuclear decay data displaying annually varying periodic fluctuations. The analyzed data were obtained from three distinct data sets: 32Si and 36Cl decays reported by an experiment performed at the Brookhaven National Laboratory (BNL), 56Mn decay reported by the Children's Nutrition Research Center (CNRC), but also performed at BNL, and 226Ra decay reported by an experiment performed at the Physikalisch-Technische Bundesanstalt (PTB) in Germany. All three data sets exhibit the same primary frequency mode consisting of an annual period. Additional spectral comparisons of the data to local ambient temperature, atmospheric pressure, relative humidity, Earth-Sun distance, and their reciprocals were performed. No common phases were found between the factors investigated and those exhibited by the nuclear decay data. This suggests that either a combination of factors was responsible, or that, if it was a single factor, its effects on the decay rate experiments are not a direct synchronous modulation. We conclude that the annual periodicity in these data sets is a real effect, but that further study involving additional carefully controlled experiments will be needed to establish its origin.

  5. Potential of GPS Common Clock Single-differences for Deformation Monitoring

    NASA Astrophysics Data System (ADS)

    Schön, Steffen; Pham, Hue Kiem; Kersten, Tobias; Leute, Julia; Bauch, Andreas

    2016-03-01

    Global satellite navigation systems (GNSS) are a standard measurement device for deformation monitoring. In many applications, double-differences are used to reduce distance dependent systematic effects, as well as to eliminate the receiver and satellites clock errors. However, due to the navigation principle of one way ranging used in GPS, the geometry of the subsequent adjustment is weakened. As a result, the height component is generally determined three times less precisely than the horizontal coordinates. In addition, large correlations between the height and elevation dependent effects exist such as tropospheric refraction, mismodelled phase center variations, or multipath which restricts the attainable accuracy. However, for a kinematic analysis, i. e. for estimating high rate coordinate time series, the situation can be significantly improved if a common clock is connected to different GNSS receivers in a network or on a baseline. Consequently, between-station single-differences are sufficient to solve for the baseline coordinates. The positioning geometry is significantly improved which is reflected by a reduction of the standard deviation of kinematic heights by about a factor 3 underlining the benefits of this new approach. Real data from baselines at the Physikalisch-Technische Bundesanstalt campus at Braunschweig where receivers are connected over 290 m via an optical fiber link to a common clock was analysed.

  6. Uncertainty of cesium-beam time standards due to beam asymmetry

    NASA Astrophysics Data System (ADS)

    Becker, G.

    1980-12-01

    As a consequence of the spatial phase distribution in the resonators of cesium-beam time and frequency standards, the generated frequency depends on the specific path of the atomic beam. A change of the position of the atomic beam source may result in a beam displacement normal to the beam direction. For a deflection system consisting of a combination of quadrupole and hexapole magnets for two-dimensional beam deflection, the displacement of the center of mass of the beam resulting from a misalignment of the beam source is computed. To this end, the distribution of the beam intensity on the collector is first determined. It is shown that for the cesium-beam time and frequency standard CS1 of the Physikalisch-Technische Bundesanstalt (PTB), the uncertainty of the position of the center of mass of the beam entails a contribution to the uncertainty of the standard of less than 1 x 10 to the -15th. The amount of the displacement of the center of mass of the beam can be determined from the decrease of the beam flux on the collector caused by an adjustment of the beam source.

  7. Learning tumor diagnostics and medical image processing via the WWW--the case-based radiological textbook ODITEB.

    PubMed

    Horsch, A; Balbach, T; Melnitzki, S; Knauth, J

    2000-09-01

    New Internet technologies offer excellent chances to build high-quality on-line learning media for the education in medicine. Especially, the teaching of diagnostics with medical imaging as well as medical image processing can be supported by the excellent visualization and interaction capabilities. In cooperation with three radiological departments at German universities in Munich, Erlangen and Würzburg, the case-based open distributed Internet text book (ODITEB) for tumor diagnosis of the GI-tract, liver, pancreas and thorax has been developed at the Institut für Medizinische Statistik und Epidemiologie (IMSE) of the Technische Universität München. It offers a big collection of clinical tumor cases located on servers at the provider sites Munich, Erlangen and Würzburg, visualization and interaction similar to a real CT or MRI console, original DICOM data, X-rays and endoscopic and endosonographic videos, and expert-guided tours through the cases. In a first evaluation in summer 1998, 32 medical students graded the application with 1.9 ('good') on a scale from 1 ('very good') to 5 ('very bad'). The textbook supports German language, an English version is in preparation. In a second part, it contains lessons in medical image processing for students of medical informatics. An ODITEB release 2 with several improvements will be finished until February 2000. The use of the textbook is free of cost. PMID:10978908

  8. Numerical modeling of thermocapillary two-phase flows with evaporation using a two-scalar approach for heat transfer

    NASA Astrophysics Data System (ADS)

    Ma, C.; Bothe, D.

    2013-01-01

    A one-field model is derived from the sharp interface continuum mechanical balances for two-phase evaporative and thermocapillary flows. Emphasis is put on a clear distinction of the different velocities at the interface which appear due to phase transfer. The one-field model is solved numerically within a Finite Volume scheme and the interface is captured using an extended Volume of Fluid method, where the interface is reconstructed linearly with the PLIC technique. The numerical heat transfer is based on a two-scalar approach where two separate temperature fields are used for the temperature inside the two phases. This results in an accurate treatment of the interfacial heat transfer, specifically the interface temperature which is crucial numerically, both for evaporation and thermocapillarity. The method is validated for two-phase heat conduction, with analytical solution in case of no evaporation and with experimental measurement in case of incorporated evaporation effect. The method is applied to realistic cases dealing with non-uniformly heated thin liquid films, i.e. liquid films on (i) structured heated substrates and (ii) locally heated substrates. The numerical predictions in terms of flow pattern, surface deformation, temperature and velocity are compared with experiments conducted at the Université Libre de Bruxelles for (i) and at the Technische Universität Darmstadt for (ii). Qualitative agreement is achieved and shows the potential of this approach to simulate thermocapillary flows with dynamically deformable interfaces combined with evaporation.

  9. The Rules of Ferrous Metallurgy

    PubMed Central

    2010-01-01

    The ways in which the sciences have been delineated and categorized throughout history provide insights into the formation, stabilization, and establishment of scientific systems of knowledge. The Dresdener school’s approach for explaining and categorizing the genesis of the engineering disciplines is still valid, but needs to be complemented by further-reaching methodological and theoretical reflections. Pierre Bourdieu’s theory of social practice is applied to the question of how individual agents succeed in influencing decisively a discipline’s changing object orientation, institutionalisation and self-reproduction. Through the accumulation of social, cultural and economic capital, they succeed in realising their own organisational ideas and scientific programs. Key concepts for the analysis include the struggle for power and resources, monopolies of interpretation, and the degree of autonomy. A case study from the Aachener Technische Hochschule shows that the consolidation of ferrous metallurgy can be conceived as a symbolical struggle between Fritz Wüst, professor for ferrous metallurgy, and the German Iron and Steel Institute, leading to a construction of a system of differences in which scientists accepted being scientists rather than entrepreneurs, and entrepreneurs accepted becoming entrepreneurs and renounced science.

  10. PREFACE: Electrorheological fluids and magnetorheological suspensions Electrorheological fluids and magnetorheological suspensions

    NASA Astrophysics Data System (ADS)

    Odenbach, Stefan; Borin, Dmitry

    2010-08-01

    The 11th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (ERMR08) was organized between 25-29 August 2008 at the Technische Universität Dresden in Germany. The conference's scientific program focused on the synthesis, characterization and application of fluids which can be controlled by external electric or magnetic fields. Within this framework electrorheological fluids, magnetorheological suspensions, ferrofluids and—for the first time—magnetorheological elastomers, which have attracted great interest in recent years, formed the class of materials discussed during the conference. With more than 180 participants from 24 different countries and 85 oral presentations in non-parallel sessions, including 8 plenary talks and 81 posters, it has been the largest ERMR meeting held during the last decade. This growth is at least partly driven by the synthesis of improved fluids and elastomers, which open new possibilities for applications as well as in basic research characterizing the flow and properties of such materials under the influence of external magnetic and electric fields. The general proceedings of ERMR08 include 116 peer-reviewed papers covering all conference topics. They were published in Journal of Physics: Conference Series volume 149 in 2009. The present special issue of Journal of Physics: Condensed Matter contains six selected papers dealing with basic research problems which will be of general interest to the condensed matter community. We hope that this selection will provide an insight into the fascination of soft matter controlled by external fields.

  11. Establishing an optimized patient-specific verification program for volumetric modulated arc therapy

    SciTech Connect

    Serna, Alfredo; Mata, Fernando; Puchades, Vicente

    2013-10-01

    Quality assurance (QA) of volumetric modulated arc therapy (VMAT) increases the workload significantly. We compared the results from 4 verification methods to establish an efficient VMAT QA. Planning for VMAT treatments was carried out for 40 consecutive patients. Pretreatment verifications were carried out with ion chamber array Physikalish-Technische Werkstätten (PTW729), electronic portal dosimetry (EPID), ion chamber measurements, and independent dose calculation with Diamond program. 2D analyses were made using the gamma analysis (3 mm distance to agreement and 3% dose difference relative to maximum, 10% dose threshold). Average point dose difference calculated by Eclipse relative to ion chamber measurements and Diamond were 0.1%±0.9% and 0.6%±2.2%, respectively. Average pass rate for PTW729 was 99.2%±1.9% and 98.3%±1.3% for EPID. The total required time (linac occupancy time given in parentheses) for each QA method was: PTW729 43.5 minutes (26.5 minutes), EPID 14.5 minutes (2.5 minutes), ion chamber 34.5 minutes (26.5 minutes), and Diamond 12.0 minutes (0 minute). The results were consistent and allowed us to establish an optimized protocol, considering safety and accuracy as well as workload, consisting of 2 verification methods: EPID 2D analysis and independent dose calculation.

  12. Final report on APMP supplementary comparison APMP.L-S3: Calibration of gauge blocks by mechanical comparison

    NASA Astrophysics Data System (ADS)

    Praba Drijarkara, A.

    2012-01-01

    This report summarizes the result of a comparison of length standards conducted between seven members of the Asia-Pacific Metrology Programme (APMP). Two sets of gauge blocks made of steel and tungsten carbide, each with nominal values 1 mm, 5 mm, 10 mm, 50 mm and 100 mm were used as travelling standards. The comparison was coordinated by the Research Centre for Calibration, Instrumentation and Metrology-Indonesian Institute of Sciences (KIM-LIPI) and assisted by the Korea Research Institute of Standards and Science (KRISS), sponsored by the Physikalisch-Technische Bundesanstalt (PTB) through APMP's Developing Economies' Committee (DEC). The comparison was carried out from October 2006 to January 2009. Preparatory and concluding workshops were organized to assist the participants in preparing for the comparison and analyzing it. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by APMP, according to the provisions of the CIPM Mutual Recognition Arrangement (MRA).

  13. Three-element trap filter radiometer based on large active area silicon photodiodes.

    PubMed

    Salim, S G R; Anhalt, K; Taubert, D R; Hollandt, J

    2016-05-20

    This paper shows the opto-mechanical design of a new filter radiometer built at the Physikalisch-Technische Bundesanstalt, Germany, for the accurate determination of the thermodynamic temperature of high-temperature blackbodies. The filter radiometer is based on a three-element reflection-type trap detector that uses three large active area silicon photodiodes. Its spectral coverage and field of view are defined by a detachable narrow-band filter and a diamond-turned precision aperture, respectively. The temperature of the filter radiometer is stabilized using a water-streamed housing and is measured using a thin-film platinum thermometer placed onto the first photodiode element. The trap "mount" has been made as compact as possible, which, together with the large active area of the chosen photodiodes, allows a wide field of view. This work presents the design of the filter radiometer and discusses the criteria that have been considered in order for the filter radiometer to suit the application. PMID:27411121

  14. Development and evaluation of thermal model reduction algorithms for spacecraft

    NASA Astrophysics Data System (ADS)

    Deiml, Michael; Suderland, Martin; Reiss, Philipp; Czupalla, Markus

    2015-05-01

    This paper is concerned with the topic of the reduction of thermal models of spacecraft. The work presented here has been conducted in cooperation with the company OHB AG, formerly Kayser-Threde GmbH, and the Institute of Astronautics at Technische Universität München with the goal to shorten and automatize the time-consuming and manual process of thermal model reduction. The reduction of thermal models can be divided into the simplification of the geometry model for calculation of external heat flows and radiative couplings and into the reduction of the underlying mathematical model. For simplification a method has been developed which approximates the reduced geometry model with the help of an optimization algorithm. Different linear and nonlinear model reduction techniques have been evaluated for their applicability in reduction of the mathematical model. Thereby the compatibility with the thermal analysis tool ESATAN-TMS is of major concern, which restricts the useful application of these methods. Additional model reduction methods have been developed, which account to these constraints. The Matrix Reduction method allows the approximation of the differential equation to reference values exactly expect for numerical errors. The summation method enables a useful, applicable reduction of thermal models that can be used in industry. In this work a framework for model reduction of thermal models has been created, which can be used together with a newly developed graphical user interface for the reduction of thermal models in industry.

  15. Collection of cometary dust

    NASA Astrophysics Data System (ADS)

    Lell, P.; Igenbergs, E.; Kuczera, H.; Pailer, N.

    Rendezvous Missions to Comets lead to low velocities at the nucleus of the comet. The resulting impact velocity of the cometary dust on a target will range between 10 and 400 m/s. The dust particle which impacts on a target can be collected for a subsequent in-situ analysis. The collection efficiency of a target depends in addition to obvious geometrical conditions upon the surface of the target. The surface characteristics can be divided into two groups: ``dirty'' surfaces, covered with silicate or hydrocarbon compounds (for example vacuum grease), ``clean'' surfaces, like gold (with additional sputtering). This paper deals with the experimental and theoretical investigation of the collection efficiency of ``clean'' targets. Laboratory experiments are described which were conducted at the Technische Universität München, Lehrstuhl für Raumfahrttechnik, and the Max-Planck-Institut für Kernphysik, Heidelberg. In both experiments an electromagnetic accelerator is used to accelerate different types of dust in vacuum to velocities between 10 and 400 m/s. The target is then examined under the microscope and a secondary ion mass spectrometer (which is a model of the laboratory carried on board of the spacecraft for ``in situ'' analysis). The adhesion of the dust grains at the target is evaluated experimentally in an ultracentrifuge.

  16. A Primary Dead-Weight Tester for Pressures (0.05–1.0) MPa

    PubMed Central

    Jain, Kamlesh; Bowers, Walt; Schmidt, James W.

    2003-01-01

    Recent advances in technology on two fronts, 1) the fabrication of large-diameter pistons and cylinders with good geometry, and 2) the ability to measure the dimensions of these components with high accuracy, have allowed dead-weight testers at the National Institute of Standards and Technology (NIST) to generate pressures that approach total relative uncertainties previously obtained only by manometers. This paper describes a 35 mm diameter piston/cylinder assembly (known within NIST as PG-39) that serves as a pressure standard in which both the piston and the cylinder have been accurately dimensioned by Physikalisch Technische Bundesanstalt (PTB). Both artifacts (piston and cylinder) appeared to be round within ±30 nm and straight within ±100 nm over a substantial fraction of their heights. Based on the diameters at 20 °C provided by PTB (±15 nm) and on the good geometry of the artifact, the relative uncertainties for the effective area were estimated to be about 2.2 × 10−6 (1σ).

  17. Evaluation of a digital data acquisition system and optimization of n-{gamma} discrimination for a compact neutron spectrometer

    SciTech Connect

    Giacomelli, L.; Zimbal, A.; Reginatto, M.; Tittelmeier, K.

    2011-01-15

    A compact NE213 liquid scintillation neutron spectrometer with a new digital data acquisition (DAQ) system is now in operation at the Physikalisch-Technische Bundesanstalt (PTB). With the DAQ system, developed by ENEA Frascati, neutron spectrometry with high count rates in the order of 5x10{sup 5} s{sup -1} is possible, roughly an order of magnitude higher than with an analog acquisition system. To validate the DAQ system, a new data analysis code was developed and tests were done using measurements with 14-MeV neutrons made at the PTB accelerator. Additional analysis was carried out to optimize the two-gate method used for neutron and gamma (n-{gamma}) discrimination. The best results were obtained with gates of 35 ns and 80 ns. This indicates that the fast and medium decay time components of the NE213 light emission are the ones that are relevant for n-{gamma} discrimination with the digital acquisition system. This differs from what is normally implemented in the analog pulse shape discrimination modules, namely, the fast and long decay emissions of the scintillating light.

  18. Nanoscale Calibration Standards and Methods: Dimensional and Related Measurements in the Micro- and Nanometer Range

    NASA Astrophysics Data System (ADS)

    Wilkening, Günter; Koenders, Ludger

    2005-08-01

    The quantitative determination of the properties of micro- and nanostructures is essential in research and development. It is also a prerequisite in process control and quality assurance in industry. The knowledge of the geometrical dimensions of structures in most cases is the base, to which other physical and chemical properties are linked. Quantitative measurements require reliable and stable instruments, suitable measurement procedures as well as appropriate calibration artefacts and methods. The seminar "NanoScale 2004" (6th Seminar on Quantitative Microscopy and 2nd Seminar on Nanoscale Calibration Standards and Methods) at the National Metrology Institute (Physikalisch-Technische Bundesanstalt PTB), Braunschweig, Germany, continues the series of seminars on Quantitative Microscopy. The series stimulates the exchange of information between manufacturers of relevant hard- and software and the users in science and industry. Topics addressed in these proceedings are a) the application of quantitative measurements and measurement problems in: microelectronics, microsystems technology, nano/quantum/molecular electronics, chemistry, biology, medicine, environmental technology, materials science, surface processing b) calibration & correction methods: calibration methods, calibration standards, calibration procedures, traceable measurements, standardization, uncertainty of measurements c) instrumentation and methods: novel/improved instruments and methods, reproducible probe/sample positioning, position-measuring systems, novel/improved probe/detector systems, linearization methods, image processing

  19. Einleitung

    NASA Astrophysics Data System (ADS)

    Lange, Kurt

    Das Fließpressen zählt neben dem Stauchen und Gleitziehen zu den Kernverfahren des Kaltmassivumformens. In beschränktem Maße wird es auch im halbwarmen Bereich zwischen 600ºC und 800°C werkstoff- oder verfahrensbedingt angewandt. Besondere technisch-wirtschaftliche Bedeutung hat das Kaltfließpressen von Stahl erlangt, nachdem 1934 durch Phosphatieren der Rohteile nach dem Singer-Patent die sichere Umformung von Stahlwerkstoffen in Stahlwerkzeugen ohne Kaltverschweißen möglich geworden war. Die Werkstückmassen liegen beim Kaltfließpressen zwischen wenigen Gramm und einigen Kilogramm, seltener auch darüber. Grenzen sind die Werkzeugbelastung einerseits und die hohen Umformkräfte andererseits. Grundsätzlich lassen sich fast alle knetbaren Metalle durch Fließpressen umformen. Heute ist diese Verfahrensgruppe eine leistungsfähige Technologie, die die Fertigung präziser, geometrisch komplexer, hochbeanspruchbarer Werkstücke aus hochfesten Stählen für weite Einsatzbereiche mit geringstem Werkstoffeinsatz ermöglicht.

  20. (Depth-dose curves of the beta reference fields (147)Pm, (85)Kr and (90)Sr/(90)Y produced by the beta secondary standard BSS2.

    PubMed

    Brunzendorf, Jens

    2012-08-01

    The most common reference fields in beta dosimetry are the ISO 6980 series 1 radiation fields produced by the beta secondary standard BSS2 and its predecessor BSS. These reference fields require sealed beta radiation sources ((147)Pm, (85)Kr or (90)Sr/(90)Y) in combination with a source-specific beam-flattening filter, and are defined only at a given distance from the source. Every radiation sources shipped with the BSS2 is sold with a calibration certificate of the Physikalisch-Technische Bundesanstalt. The calibration workflow also comprises regular depth-dose measurements. This work publishes complete depth-dose curves of the series 1 sources (147)Pm, (85)Kr and (90)Sr/(90)Y in ICRU tissue up to a depth of 11 mm,when all electrons are stopped. For this purpose, the individual depth-dose curves of all BSS2 sources calibrated so far have been determined, i.e. the complete datasets of all BSS2 beta sources have been re-evaluated. It includes 191 depth-dose curves of 116 different sources comprising more than 2200 data points in total. Appropriate analytical representations of the nuclide-specific depth-dose curves are provided for the first time. PMID:22267274

  1. Argan woodlands in South Morocco as an area of conflict between degradation and sustainable land use

    NASA Astrophysics Data System (ADS)

    Kirchhoff, Mario; Kagermeier, Andreas; Ries, Johannes B.

    2016-04-01

    The Argan woodlands are endemic for South Morocco and prone to degradation through expanding and intensifying agriculture and overgrazing. Unvegetated areas extend further due to degradation of soil and vegetation. Here infiltration is less than on vegetated areas, while runoff and soil erosion increase. The sale of the highly valuable oil, gained from the seeds of the argan tree, can be seen as an economic alternative for the region and a chance of survival for the argan woodlands. With the introduction of women's cooperatives for the production and sale of the oil, the Gesellschaft für Technische Zusammenarbeit (GTZ, Association for Technical Cooperation) hoped to halt argan degradation from 1995 to 2002. The effects of this approach shall be studied in a proposed DFG-project. The erosion gradient between soils under canopy cover and intertree areas in varying stages of degradation will be at the center of the analysis. Insight into onsite and offsite degradation shall be gained through the measurement of runoff and erosion rates, which lead to rill and gully erosion downslope. Measurements of soil chemical and physical properties might also help indicate when an argan woodland can be classified as natural. Furthermore to be studied are the effects of the new found value of the Argan woodlands among the local population with focus on regional tourism and a possible reduction of grazing pressure. Sustainable soil management in combination with the needs of the local population is essential for a sustainable land use in the region.

  2. Key comparison BIPM.RI(I)-K4 of the absorbed dose to water standards of the PTB, Germany and the BIPM in 60Co gamma radiation

    NASA Astrophysics Data System (ADS)

    Kessler, C.; Burns, D. T.; Kapsch, R.-P.; Krauss, A.

    2016-01-01

    An indirect comparison has been made of the standards for absorbed dose to water in 60Co radiation of the Physikalisch-Technische Bundesanstalt, (PTB), Germany and of the Bureau International des Poids et Mesures (BIPM). The measurements at the BIPM were carried out in October 2015. The comparison result, based on the calibration coefficients for two transfer standards and evaluated as a ratio of the PTB and the BIPM standards for absorbed dose to water, is 0.9977 with a combined standard uncertainty of 3.8 × 10-3. The results are analysed and presented in terms of degrees of equivalence for entry in the BIPM key comparison database. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  3. Phasenübergänge

    NASA Astrophysics Data System (ADS)

    Heintze, Joachim

    Bisher haben wir nur das thermische Verhalten von Stoffen einheitlicher Konsistenz diskutiert. Eines der auffälligsten Phänomene in der Physik der Wärme ist aber, dass ein Stoff in verschiedenen Aggregatzuständen vorliegen kann: fest, flüssig oder gasförmig, und dass durch Wärmezufuhr und -abfuhr Übergänge zwischen diesen verschiedenen Phasen bewirkt werden. Zunächst werden wir die Phasenübergänge flüssig-gasförmig und fest-gasförmig ausführlich diskutieren. Dann zeigen wir, dass der Phasenübergang fest-flüssig auf ganz ähnliche Weise beschrieben werden kann. Eine zusammenfassende Darstellung der Phasenübergänge ist in der Form von Zustandsdiagrammen möglich. Die Untersuchung solcher Diagramme führt auf das interessante Phänomen des kritischen Punktes. Am Schluss des Kapitels betrachten wir Phasenübergänge in Zweistoffsystemen. Sie weisen einige Eigenschaften auf, die nicht nur merkwürdig und physikalisch interessant, sondern vor allem auch technisch von Bedeutung sind.

  4. > Einleitung

    NASA Astrophysics Data System (ADS)

    Spath, Dieter; Pischetsrieder, Bernd

    Rund 40 Prozent aller Fahrzeuge fahren elektrisch. Ein Zustand, der aus heutiger Sicht noch in weiter Ferne liegt, war vor über 100 Jahren bereits Realität. Um 1900, einige Jahre nach der Erfindung des Automobils, wurden Fahrzeuge durch unterschiedliche Antriebskonzepte angetrieben. Die drei wichtigsten waren Dampfantrieb, Elektroantrieb und der Benzinmotor. Durch die überlegene Energiedichte und eine kostengünstige sowie scheinbar unendliche Verfügbarkeit des Energieträgers Öl entwickelte sich der Verbrennungsmotor zum dominanten Antriebskonzept. Der Einsatz von Elektrofahrzeugen beschränkte sich im Verlauf des 20. Jahrhunderts auf wenige Nischenanwendungen. Der verbrennungsmotorbasierte Antriebsstrang ist dem Elektroantrieb auch heute noch technisch und ökonomisch überlegen. Die Randbedingungen ändern sich jedoch. Die Verknappung des fossilen Brennstoffs Öl und die stetige Verschärfung der CO2-Emissionsziele in Verbindung mit einer starken Zunahme individueller Mobilität im asiatischen Raum und vielen weiteren Regionen der Welt stellen den Verbrennungsmotors als die dominante Antriebstechnologie in Frage. Trotz des Optimierungspotentials, welches auch nach über 120-jähriger Entwicklung noch im Verbrennungsmotor liegt, ist diese Technologie immer mit lokalen Schadstoff- und Lärmemissionen verbunden. Die Notwendigkeit der Reduktion von Treibhausgasen verbunden mit einem steigenden Urbanisierungsgrad wird in Zukunft einen Technologiewechsel vom Verbrennungsmotor zum elektrischen Antrieb attraktiv machen. Dieser Technologiewechsel bedeutet jedoch weit mehr als das Austauschen des Antriebsstranges, Elektromobilität ist ein komplexes Themengebiet mit unterschiedlichen Dimensionen.

  5. Capabilities and limitations of the self-calibration of angle encoders

    NASA Astrophysics Data System (ADS)

    Geckeler, Ralf D.; Link, Alfred; Krause, Michael; Elster, Clemens

    2014-05-01

    At the Physikalisch-Technische Bundesanstalt (PTB), a self-calibration method for the fast and precise in situ calibration of angle encoders without recourse to external reference standards has been developed. It relies on a suitable geometric arrangement of multiple reading heads which read out the radial grating of the angle encoder at different angular positions. Fourier-based algorithms are used to analyse the measurement differences of pairs of heads to recover the graduation error of the grating. A comprehensive overview, both theoretical and experimental, of the capabilities and limitations of the self-calibration method is presented, including experimental data obtained with the high-precision primary angle standard of PTB. The evaluation and, where it is possible, correction of error influences due to lateral shifts of the centre of the encoder's grating during its rotation, including its eccentricity, the reading heads’ angular positions, and their non-uniform response, are discussed in detail, as well as the resulting uncertainty budget.

  6. [Basic concept for the judgement of the results of dustfall measuring in the Alps (author's transl)].

    PubMed

    Kofler, W; Benger, J

    1976-02-01

    At the time extensive measurements are made in the Austrian part of the Alps to find out the elevation of the fundamental load of dustfall according to the methode of BERGERHOFF. Thereby the authors had to solve the fundamental question to find a system for estimation. In Austria the results of measurements of dustfall were classified usually according to the "Technische Anleitung zur Reinhaltung der Luft 1964." It appeared that the introduction did not achieve the problem because of the special geografical, meteorological and economical data of the researched part of the Alps which at that time has about 30 000 km2. Similar applies to the new standards of the TAL 1974 and that recommendations of the "Deutscher Bäderverband" to estimate health resorts, recreation areas and mineral springs. Therefore a special model for estimating was developed which differentiate among the average of a year and the maximum of the average of a month, the general housing-areas, recreation areas and standards for industrial areas. The suggested limits are under the limits which are used today in Germany. The results of measurements of dustfall are discussed. PMID:1274505

  7. Thermographic techniques and adapted algorithms for automatic detection of foreign bodies in food

    NASA Astrophysics Data System (ADS)

    Meinlschmidt, Peter; Maergner, Volker

    2003-04-01

    At the moment foreign substances in food are detected mainly by using mechanical and optical methods as well as ultrasonic technique and than they are removed from the further process. These techniques detect a large portion of the foreign substances due to their different mass (mechanical sieving), their different colour (optical method) and their different surface density (ultrasonic detection). Despite the numerous different methods a considerable portion of the foreign substances remain undetected. In order to recognise materials still undetected, a complementary detection method would be desirable removing the foreign substances not registered by the a.m. methods from the production process. In a project with 13 partner from the food industry, the Fraunhofer - Institut für Holzforschung (WKI) and the Technische Unsiversität are trying to adapt thermography for the detection of foreign bodies in the food industry. After the initial tests turned out to be very promising for the differentiation of food stuffs and foreign substances, more and detailed investigation were carried out to develop suitable algorithms for automatic detection of foreign bodies. In order to achieve -besides the mere visual detection of foreign substances- also an automatic detection under production conditions, numerous experiences in image processing and pattern recognition are exploited. Results for the detection of foreign bodies will be presented at the conference showing the different advantages and disadvantages of using grey - level, statistical and morphological image processing techniques.

  8. Observing of entrainment using small UAS

    NASA Astrophysics Data System (ADS)

    Martin, S.; Bange, J.; Beyrich, F.

    2012-04-01

    Entrainment processes between the atmospheric boundary layer and the free atmosphere are important concerning vertical exchange of momentum, energy, water vapor, trace gases and aerosol. The transition zone between the convectively mixed boundary layer and the stably stratified free atmosphere is called the entrainment zone (EZ). The EZ restrains the domain of turbulence by a temperature inversion and acts as a lid to pollutants. Measurement flights of the mini meteorological aerial vehicle (M2AV) of the Technische Universität Braunschweig were performed in spring 2011 to determine the capability of the unmanned aerial system (UAS) to measure the structure of the EZ. The campaign took place at the Meteorological Observatory Lindenberg / Richard-Aßmann-Observatory of the German Meteorological Service, which is located close to Berlin. Besides the M2AV flights, standard observations were performed by a 12 m and 99 m tower, a sodar, ceilometer and radiosondes. A tethered balloon with measurement units at six different levels was operated especially for this campaign. The measurements of these systems were used to determine the inversion layer and to capture its diurnal cycle. The talk will be focused on vertical profiles of the M2AV up to the free atmosphere, detailed analysis of spatial series of w'θ' at different altitudes and on vertical profiles of normalized variances of the vertical wind component and the potential temperature.

  9. Industry: Power fluidics - the state in Europe

    SciTech Connect

    Whetton, C.

    1996-03-01

    Fluidics is the science of fluid control without moving parts. To many people, fluidics is dead technology, long displaced by electronic logic. In the case of low-power fluidics, this is undoubtedly true except for a few highly specialized cases. Power fluidics, the control of large, industrial-scale flows, is very much alive and well, controlling sewer systems, {open_quotes}deslugging{close_quotes} mixed oil and gas flows, pumping highly corrosive radioactive liquids, and handling various applications in the pharmaceutical industry. The first fluidic device was the vortex diode or vortex throttle, developed in 1936 by Thomas Zobel of the Muenchen Technische Hochschule (Technical University of Munich). This device, the prototype of which still exists in working order, allowed fluid to flow easily in one direction, but offered a high resistance to reverse flow. Typical forward to reverse flow rates were 10:1, with a similar pressure ratio of 100:1. By adding a control port to the vortex diode, a vortex amplifier was achieved so that a large fluid flow could be controlled by a much smaller flow without moving parts. By the mid-1960s, practical vortex amplifiers had been developed and applied to the control of {open_quotes}difficult{close_quotes} fluids. With no moving parts, fluidic devices required minimal maintenance, a definite bonus if the device was located in a hot area. 6 figs.

  10. The Angular Distribution of Neutrons Scattered from Deuterium below 2 MeV

    NASA Astrophysics Data System (ADS)

    Nankov, N.; Plompen, A. J. M.; Kopecky, S.; Kozier, K. S.; Roubtsov, D.; Rao, R.; Beyer, R.; Grosse, E.; Hannaske, R.; Junghans, A. R.; Massarczyk, R.; Schwengner, R.; Yakorev, D.; Wagner, A.; Stanoiu, M.; Canton, L.; Nolte, R.; Röttger, S.; Beyer, J.; Svenne, J.

    2014-05-01

    Neutron elastic scattering measurements were carried out at the nELBE neutron time-of-flight facility at a 6 m flight path. Energies below 2 MeV were studied using a setup consisting of eight 6Li-glass detectors placed at nominal angles of 15∘ and 165∘ with respect to the incident neutron beam. A deuterated polyethylene sample with 99.999% enrichment in deuterium was used. These angles were chosen since an earlier study showed that the ratio of the differential cross section at these angles is the most sensitive to differences in evaluated files and model calculations. Accurate 165∘/15∘ angle ratios were obtained. Above 1 MeV these are somewhat larger than given by ENDF/B-VII. Simultaneously the early day experiments using a proportional counter to infer angular distributions from deuterium recoil pulse height distributions are being studied through a new experiment with such a device at the Physikalisch-Technische Bundesanstalt (PTB). At 500 keV this experiment favors ENDF/B-VII over JENDL-4.0, while at lower energies agreement with the data is similar.

  11. Oral histories in meteoritics and planetary science - XXII: John T. Wasson

    NASA Astrophysics Data System (ADS)

    Sears, Derek W. G.

    2014-04-01

    In this interview, John Wasson (Fig. 1) describes his childhood and undergraduate years in Arkansas and his desire to pursue nuclear chemistry as a graduate student at MIT. Upon graduation, John spent time in Munich (Technische Hochschule), the Air Force Labs in Cambridge, MA, and a sabbatical at the University of Bern where he developed his interests in meteorites. Upon obtaining his faculty position at UCLA, John established a neutron activation laboratory and began a long series of projects on the bulk compositions of iron meteorites and chondrites. He developed the chemical classification scheme for iron meteorites, gathered a huge set of iron meteorite compositional data with resultant insights into their formation, and documented the refractory and moderately volatile element trends that characterize the chondrites and chondrules. He also spent several years studying field relations and compositions of layered tektites from Southeast Asia, proposing an origin by radiant heating from a mega-Tunguska explosion. Recently, John has explored oxygen isotope patterns in meteorites and their constituents believing the oxygen isotope results to be some of the most important discoveries in cosmochemistry. John also describes the role of postdoctoral colleagues and their important work, his efforts in the reorganization and modernization of the Meteoritical Society, his contributions in reshaping the journal Meteoritics, and how, with UCLA colleagues, he organized two meetings of the society. John Wasson earned the Leonard Medal of the Meteoritical Society in 1992 and the J. Lawrence Smith Medal of the National Academy in 2003.

  12. Stray-field-induced quadrupole shift and absolute frequency of the 688-THz {sup 171}Yb{sup +} single-ion optical frequency standard

    SciTech Connect

    Tamm, Chr.; Weyers, S.; Lipphardt, B.; Peik, E.

    2009-10-15

    We report experimental investigations of a single-ion optical frequency standard based on {sup 171}Yb{sup +}. The ion is confined in a cylindrically symmetric radiofrequency Paul trap. The reference transition is the {sup 2}S{sub 1/2}(F=0)-{sup 2}D{sub 3/2}(F{sup '}=2) electric quadrupole transition at 688 THz. Using a differential measurement scheme, we determine the shift of the reference transition frequency that occurs due to the interaction of the electric quadrupole moment of the {sup 2}D{sub 3/2} state with the gradient of the electrostatic stray field in the trap. We determine an upper limit for the instability of the quadrupole shift over times between 100 s to 20 h. We also observe the variations in the shift and in the applied stray-field compensation voltages that result from loading a new ion into the trap and during a subsequent storage period of 74 days. This information is utilized to measure the absolute frequency of the reference transition with an uncertainty that is a factor of 3 smaller than that of the previous measurement. Using a fiber laser based optical frequency comb generator and the cesium fountain clock CSF1 of PTB (Physikalisch-Technische Bundesanstalt), the frequency at 300 K temperature is determined as 688 358 979 309 306.62{+-}0.73 Hz.

  13. ARGon{sup 3}: ''3D appearance robot-based gonioreflectometer'' at PTB

    SciTech Connect

    Hoepe, A.; Atamas, T.; Huenerhoff, D.; Teichert, S.; Hauer, K.-O.

    2012-04-15

    At the Physikalisch-Technische Bundesanstalt, the National Metrology Institute of Germany, a new facility for measuring visual appearance-related quantities has been built up. The acronym ARGon{sup 3} stands for ''3D appearance robot-based gonioreflectometer''. Compared to standard gonioreflectometers, there are two main new features within this setup. First, a photometric luminance camera with a spatial resolution of 28 {mu}m on the device under test (DUT) enables spatially high-resolved measurements of luminance and color coordinates. Second, a line-scan CCD-camera mounted to a spectrometer provides measurements of the radiance factor, respectively the bidirectional reflectance distribution function, in full V({lambda})-range (360 nm-830 nm) with arbitrary angles of irradiation and detection relative to the surface normal, on a time scale of about 2 min. First goniometric measurements of diffuse reflection within 3D-space above the DUT with subsequent colorimetric representation of the obtained data of special effect pigments based on the interference effect are presented.

  14. Radiopurity of CaWO{sub 4} crystals for direct dark matter search with CRESST and EURECA

    SciTech Connect

    Münster, A.; Sivers, M. v.; Erb, A.; Feilitzsch, F. v.; Gütlein, A.; Lanfranchi, J.-C.; Potzel, W.; Angloher, G.; Bento, A.; Hauff, D.; Petricca, F.; Pröbst, F.; Bucci, C.; Canonica, L.; Gorla, P.; Laubenstein, M.; Jochum, J.; Loebell, J.; Kraus, H.; Ortigoza, Y. E-mail: msivers@ph.tum.de; and others

    2014-05-01

    The direct dark matter search experiment CRESST uses scintillating CaWO{sub 4} single crystals as targets for possible WIMP scatterings. An intrinsic radioactive contamination of the crystals as low as possible is crucial for the sensitivity of the detectors. In the past CaWO{sub 4} crystals operated in CRESST were produced by institutes in Russia and the Ukraine. Since 2011 CaWO{sub 4} crystals have also been grown at the crystal laboratory of the Technische Universität München (TUM) to better meet the requirements of CRESST and of the future tonne-scale multi-material experiment EURECA. The radiopurity of the raw materials and of first TUM-grown crystals was measured by ultra-low background γ-spectrometry. Two TUM-grown crystals were also operated as low-temperature detectors at a test setup in the Gran Sasso underground laboratory. These measurements were used to determine the crystals' intrinsic α-activities which were compared to those of crystals produced at other institutes. The total α-activities of TUM-grown crystals as low as 1.23±0.06 mBq/kg were found to be significantly smaller than the activities of crystals grown at other institutes typically ranging between ∼ 15 mBq/kg and ∼ 35 mBq/kg.

  15. Establishing an optimized patient-specific verification program for volumetric modulated arc therapy.

    PubMed

    Serna, Alfredo; Mata, Fernando; Puchades, Vicente

    2013-01-01

    Quality assurance (QA) of volumetric modulated arc therapy (VMAT) increases the workload significantly. We compared the results from 4 verification methods to establish an efficient VMAT QA. Planning for VMAT treatments was carried out for 40 consecutive patients. Pretreatment verifications were carried out with ion chamber array Physikalish-Technische Werkstätten (PTW729), electronic portal dosimetry (EPID), ion chamber measurements, and independent dose calculation with Diamond program. 2D analyses were made using the gamma analysis (3mm distance to agreement and 3% dose difference relative to maximum, 10% dose threshold). Average point dose difference calculated by Eclipse relative to ion chamber measurements and Diamond were 0.1%±0.9% and 0.6%±2.2%, respectively. Average pass rate for PTW729 was 99.2%±1.9% and 98.3%±1.3% for EPID. The total required time (linac occupancy time given in parentheses) for each QA method was: PTW729 43.5 minutes (26.5 minutes), EPID 14.5 minutes (2.5 minutes), ion chamber 34.5 minutes (26.5 minutes), and Diamond 12.0 minutes (0 minute). The results were consistent and allowed us to establish an optimized protocol, considering safety and accuracy as well as workload, consisting of 2 verification methods: EPID 2D analysis and independent dose calculation. PMID:23540493

  16. Low-level measuring techniques for neutrons: High accuracy neutron source strength determination and fluence rate measurement at an underground laboratory

    SciTech Connect

    Zimbal, Andreas; Reginatto, Marcel; Schuhmacher, Helmut; Wiegel, Burkhard; Degering, Detlev; Zuber, Kai

    2013-08-08

    We report on measuring techniques for neutrons that have been developed at the Physikalisch-Technische Bundesanstalt (PTB), the German National Metrology Institute. PTB has characterized radioactive sources used in the BOREXINO and XENON100 experiments. For the BOREXINO experiment, a {sup 228}Th gamma radiation source was required which would not emit more than 10 neutrons per second. The determination of the neutron emission rate of this specially designed {sup 228}Th source was challenging due to the low neutron emission rate and because the ratio of neutron to gamma radiation was expected to be extremely low, of the order of 10{sup −6}. For the XENON100 detector, PTB carried out a high accuracy measurement of the neutron emission rate of an AmBe source. PTB has also done measurements in underground laboratories. A two month measurement campaign with a set of {sup 3}He-filled proportional counters was carried out in PTB's former UDO underground laboratory at the Asse salt mine. The aim of the campaign was to determine the intrinsic background of detectors, which is needed for the analysis of data taken in lowintensity neutron fields. At a later time, PTB did a preliminary measurement of the neutron fluence rate at the underground laboratory Felsenkeller operated by VKTA. By taking into account data from UDO, Felsenkeller, and detector calibrations made at the PTB facility, it was possible to estimate the neutron fluence rate at the Felsenkeller underground laboratory.

  17. Study of the Smith-Purcell effect in the relativistic regime

    SciTech Connect

    Doucas, G.; Dumitru, M.; Korschinck, G.

    1995-12-31

    We propose to investigate the spontaneous emission of radiation arising out of the interaction of a relativistic electron beam with a metallic grating (the Smith-Purcell effect). The work will concentrate, primarily, in the 50-120 {mu}m part of the infrared spectrum and will be an extension of the work begun by the Oxford-Dartmouth-Essex collaboration; one of the early objectives of the project will be to develop a quantitative understanding of the power spectrum of the emitted radiation over a wide range of emission angles. In particular, the limits of relativistic peaking of forward directed emission will be investigated. The electron beam will be produced by laser irradiation of a metallic cathode in the terminal of a small Van de Graff accelerator located in the Technische Universitaet, Muenchen. Beam energies will be in the range of 2 - 4 MeV. Initial tests on photoproduction of electrons have yielded 10 mA pulses with a width of about 20 ns. The electron pulse length is long enough to not only produce easily observed levels of spontaneous emission, but in principle gain due to stimulated emission should also be observable. Observation of gain is a second goal of the project. The manufacture of the grating chamber and the voltage tests on the accelerator will progress in parallel. This is a 3-year project and is supported, in part, by the British-German Academic Research Collaboration (ARC) program.

  18. Excitation energy transfer in intact cells and in the phycobiliprotein antennae of the chlorophyll d containing cyanobacterium Acaryochloris marina.

    PubMed

    Theiss, Christoph; Schmitt, Franz-Josef; Pieper, Jörg; Nganou, Collins; Grehn, Moritz; Vitali, Marco; Olliges, Rachel; Eichler, Hans Joachim; Eckert, Hann-Jörg

    2011-08-15

    The cyanobacterium Acaryochloris marina is unique because it mainly contains Chlorophyll d (Chl d) in the core complexes of PS I and PS II instead of the usually dominant Chl a. Furthermore, its light harvesting system has a structure also different from other cyanobacteria. It has both, a membrane-internal chlorophyll containing antenna and a membrane-external phycobiliprotein (PBP) complex. The first one binds Chl d and is structurally analogous to CP43. The latter one has a rod-like structure consisting of three phycocyanin (PC) homohexamers and one heterohexamer containing PC and allophycocyanin (APC). In this paper, we give an overview on the investigations of excitation energy transfer (EET) in this PBP-light-harvesting system and of charge separation in the photosystem II (PS II) reaction center of A. marina performed at the Technische Universität Berlin. Due to the unique structure of the PBP antenna in A. marina, this EET occurs on a much shorter overall time scale than in other cyanobacteria. We also briefly discuss the question of the pigment composition in the reaction center (RC) of PS II and the nature of the primary donor of the PS II RC. PMID:21396735

  19. SUPPLEMENTARY COMPARISON: Final report on supplementary comparison SADCMET.AUV.V-S1

    NASA Astrophysics Data System (ADS)

    Veldman, Ian; von Martens, Hans-Jürgen

    2004-01-01

    A supplementary comparison (SADC.AUV.V-S1) was organized to compare measurements of sinusoidal linear accelerations in the frequency range from 10 Hz to 10 kHz. In this bilateral comparison between the CSIR National Metrology Laboratory (CSIR-NML), South Africa and the Physikalisch-Technische Bundesanstalt (PTB), Germany both NMIs applied laser interferometry in compliance with method 3 of the international standard ISO 16063-11:1999. The complex charge sensitivity (magnitude and phase) of two different transfer standards (single-ended accelerometers) was measured at 37 frequencies. The results of the SADCMET.AUV.V-S1 are a set of comparison values and their uncertainties, and degrees of equivalence between these and between the two laboratories. From this complete set of results, six matrices of equivalence per accelerometer were selected and are demonstrated graphically. The deviations between the PTB and NML results were smaller than 0.6° and 2° for the phase shift measurements for the Endevco and Brüel & Kjær accelerometers respectively (37 measurement points each). Main text. To reach the main text of this paper, click on Final Report. The final report has been peer-reviewed and approved for publication by SADCMET, according to the provisions of the Mutual Recognition Arrangement (MRA).

  20. Monoenergetic Neutrons for Stellar Applications

    NASA Astrophysics Data System (ADS)

    Mosconi, M.; Heil, M.; Käppeler, F.; Plag, R.; Mengoni, A.; Nolte, R.

    2009-09-01

    With modern techniques, neutron-capture cross sections can be determined with uncertainties of a few percent. However, Maxwellian averaged cross sections calculated from such data require a correction (because low-lying excited states are thermally populated in the hot stellar photon bath) which has to be determined by theoretical calculations. These calculations can be improved with information from indirect measurements, in particular by the inelastic scattering cross section. For low-lying levels, the inelastically scattered neutrons are difficult to separate from the dominant elastic channel. This problem is best solved by means of pulsed, monoenergetic neutron beams. For this reason, a pulsed beam of 30 keV neutrons with an energy spread of 7 to 9 keV FWHM and a width from 10 to 15 ns has been produced at Forschungszentrum Karlsruhe using the 7Li(p, n)7Be reaction directly at the reaction threshold. With this neutron beam the inelastic scattering cross section of the first excited level at 9.75 keV in 187Os was determined with a relative uncertainty of 6%. The use of monoenergetic neutron beams has been further pursued at the Physikalisch-Technische Bundesanstalt in Braunschweig, including the 3H(p, n)3He reaction for producing neutrons with an energy of 64 keV.

  1. Next generation KATRIN high precision voltage divider for voltages up to 65kV

    NASA Astrophysics Data System (ADS)

    Bauer, S.; Berendes, R.; Hochschulz, F.; Ortjohann, H.-W.; Rosendahl, S.; Thümmler, T.; Schmidt, M.; Weinheimer, C.

    2013-10-01

    The KATRIN (KArlsruhe TRItium Neutrino) experiment aims to determine the mass of the electron antineutrino with a sensitivity of 200 meV by precisely measuring the electron spectrum of the tritium beta decay. This will be done by the use of a retarding spectrometer of the MAC-E-Filter type. To achieve the desired sensitivity the stability of the retarding potential of -18.6 kV has to be monitored with a precision of 3 ppm over at least two months. Since this is not feasible with commercial devices, two ppm-class high voltage dividers were developed, following the concept of the standard divider for DC voltages of up to 100 kV of the Physikalisch-Technische Bundesanstalt (PTB). In order to reach such high accuracies different effects have to be considered. The two most important ones are the temperature dependence of resistance and leakage currents, caused by insulators or corona discharges. For the second divider improvements were made concerning the high-precision resistors and the thermal design of the divider. The improved resistors are the result of a cooperation with the manufacturer. The design improvements, the investigation and the selection of the resistors, the built-in ripple probe and the calibrations at PTB will be reported here. The latter demonstrated a stability of about 0.1 ppm/month over a period of two years.

  2. Precision high voltage divider for the KATRIN experiment

    NASA Astrophysics Data System (ADS)

    Thümmler, Th; Marx, R.; Weinheimer, Ch

    2009-10-01

    The Karlsruhe Tritium Neutrino (KATRIN) experiment aims to determine the absolute mass of the electron antineutrino from a precise measurement of the tritium β-spectrum near its endpoint at 18.6 keV with a sensitivity of 0.2 eV c-2. KATRIN uses an electrostatic retardation spectrometer of MAC-E filter type for which it is crucial to monitor high voltages of up to 35 kV with a precision and long-term stability at the ppm level. Since devices capable of this precision are not commercially available, a new high voltage divider for direct voltages of up to 35 kV has been designed, following the new concept of the standard divider for direct voltages of up to 100 kV developed at the Physikalisch-Technische Bundesanstalt (PTB)PTB is the German National Metrology Institute providing scientific and technical services.. The electrical and mechanical design of the divider, the screening procedure for the selection of the precision resistors, and the results of the investigation and calibration at the PTB are reported here. During the latter, uncertainties at the low ppm level have been deduced for the new divider, thus qualifying it for the precision measurements of the KATRIN experiment.

  3. Gas-Monitor Detector for Intense and Pulsed VUV/EUV Free-Electron Laser Radiation

    NASA Astrophysics Data System (ADS)

    Sorokin, A. A.; Bobashev, S. V.; Feldhaus, J.; Gerth, Ch.; Gottwald, A.; Hahn, U.; Kroth, U.; Richter, M.; Shmaenok, L. A.; Steeg, B.; Tiedtke, K.; Treusch, R.

    2004-05-01

    In the framework of current developments of new powerful VUV and EUV radiation sources, like VUV free-electron-lasers or EUV plasma sources for 13-nm lithography, we developed a gas-monitor detector in order to measure the photon flux of highly intense and extremely pulsed VUV and EUV radiation in absolute terms. The device is based on atomic photoionization of a rare gas at low particle density. Therefore, it is free of degradation and almost transparent, which allows the detector to be used as a continuously working beam-intensity monitor. The extended dynamic range of the detector allowed its calibration with relative standard uncertainties of 4% in the Radiometry Laboratory of the Physikalisch-Technische Bundesanstalt at the electron-storage ring BESSY II in Berlin using spectrally dispersed synchrotron radiation at low photon intensities and its utilization for absolute photon flux measurements of high power sources. In the present contribution, we describe the design of the detector and its application for the characterization of VUV free-electron-laser radiation at the TESLA test facility in Hamburg. By first pulse resolved measurements, a peak power of more than 100 MW at a wavelength of 87 nm was detected.

  4. Radiopurity of CaWO4 crystals for direct dark matter search with CRESST and EURECA

    NASA Astrophysics Data System (ADS)

    Münster, A.; Sivers, M. v.; Angloher, G.; Bento, A.; Bucci, C.; Canonica, L.; Erb, A.; Feilitzsch, F. v.; Gorla, P.; Gütlein, A.; Hauff, D.; Jochum, J.; Kraus, H.; Lanfranchi, J.-C.; Laubenstein, M.; Loebell, J.; Ortigoza, Y.; Petricca, F.; Potzel, W.; Pröbst, F.; Puimedon, J.; Reindl, F.; Roth, S.; Rottler, K.; Sailer, C.; Schäffner, K.; Schieck, J.; Scholl, S.; Schönert, S.; Seidel, W.; Stodolsky, L.; Strandhagen, C.; Strauss, R.; Tanzke, A.; Uffinger, M.; Ulrich, A.; Usherov, I.; Wawoczny, S.; Willers, M.; Wüstrich, M.; Zöller, A.

    2014-05-01

    The direct dark matter search experiment CRESST uses scintillating CaWO4 single crystals as targets for possible WIMP scatterings. An intrinsic radioactive contamination of the crystals as low as possible is crucial for the sensitivity of the detectors. In the past CaWO4 crystals operated in CRESST were produced by institutes in Russia and the Ukraine. Since 2011 CaWO4 crystals have also been grown at the crystal laboratory of the Technische Universität München (TUM) to better meet the requirements of CRESST and of the future tonne-scale multi-material experiment EURECA. The radiopurity of the raw materials and of first TUM-grown crystals was measured by ultra-low background γ-spectrometry. Two TUM-grown crystals were also operated as low-temperature detectors at a test setup in the Gran Sasso underground laboratory. These measurements were used to determine the crystals' intrinsic α-activities which were compared to those of crystals produced at other institutes. The total α-activities of TUM-grown crystals as low as 1.23±0.06 mBq/kg were found to be significantly smaller than the activities of crystals grown at other institutes typically ranging between ~ 15 mBq/kg and ~ 35 mBq/kg.

  5. Recent work of decay spectroscopy at RIBF

    NASA Astrophysics Data System (ADS)

    Söderström, Pär-Anders

    2014-09-01

    β- and isomer-decay spectroscopy are sensitive probes of nuclear structure, and are often the only techniques capable of providing data for exotic nuclei that are producted with very low rates. Decay properties of exotic nuclei are also essential to model astrophysical events responible for the evolution of the universe such as the rp- and r-process. The EURICA project (EUROBALL RIKEN Cluster Array) has been launched in 2012 with the goal of performing spectroscopy of very exotic nuclei. Since 2012, four experimental campaigns have been successfully completed using fragmentation of 124Xe beam and in-flight-fission of 238U beam, approaching for example the key nuclei 78Ni, 110Zr, 100Sn, 128Pd, and 138Sn. This contribution highlights the experiments performed, results obtained, and discusses the future perspective of the EURICA project. In collaboration with Shunji Nishimura, Hidetada Baba, RIKEN Nishina Center; Frank Browne, Brighton University; Pieter Doornenbal, RIKEN Nishina Center; Guillaume Gey, Universite Joseph Fourier Grenoble; Tadaaki Isobe and Giuseppe Lorusso, RIKEN Nishina Center; Daniel Lubos, Technische Universitat Munchen; Kevin Mochner, University of Cologne; Zena Patel and Simon Rice, University of Surrey; Hiroyoshi Sakurai, RIKEN Nishina Center; Laura Sinclair, University of York; Toshiyuki Sumikama, Tohoku University; Jan Taprogge, Universidad Autonoma de Madrid; Zsolt Vajta, MTA Atomki; Hiroshi Watanabe, Beihang University; Jin Wu, Peking University; and Zhengyu Xu, University of Tokyo.

  6. First set of gated x-ray imaging diagnostics for the Laser Megajoule facility.

    PubMed

    Rosch, R; Trosseille, C; Caillaud, T; Allouche, V; Bourgade, J L; Briat, M; Brunel, P; Burillo, M; Casner, A; Depierreux, S; Gontier, D; Jadaud, J P; Le Breton, J P; Llavador, P; Loupias, B; Miquel, J L; Oudot, G; Perez, S; Raimbourg, J; Rousseau, A; Rousseaux, C; Rubbelynck, C; Stemmler, P; Troussel, P; Ulmer, J L; Wrobel, R; Beauvais, P; Pallet, M; Prevot, V

    2016-03-01

    The Laser Megajoule (LMJ) facility located at CEA/CESTA started to operate in the early 2014 with two quadruplets (20 kJ at 351 nm) focused on target for the first experimental campaign. We present here the first set of gated x-ray imaging (GXI) diagnostics implemented on LMJ since mid-2014. This set consists of two imaging diagnostics with spatial, temporal, and broadband spectral resolution. These diagnostics will give basic measurements, during the entire life of the facility, such as position, structure, and balance of beams, but they will also be used to characterize gas filled target implosion symmetry and timing, to study x-ray radiography and hydrodynamic instabilities. The design requires a vulnerability approach, because components will operate in a harsh environment induced by neutron fluxes, gamma rays, debris, and shrapnel. Grazing incidence x-ray microscopes are fielded as far as possible away from the target to minimize potential damage and signal noise due to these sources. These imaging diagnostics incorporate microscopes with large source-to-optic distance and large size gated microchannel plate detectors. Microscopes include optics with grazing incidence mirrors, pinholes, and refractive lenses. Spatial, temporal, and spectral performances have been measured on x-ray tubes and UV lasers at CEA-DIF and at Physikalisch-Technische Bundesanstalt BESSY II synchrotron prior to be set on LMJ. GXI-1 and GXI-2 designs, metrology, and first experiments on LMJ are presented here. PMID:27036783

  7. From plane to spatial angles: PTB's spatial angle autocollimator calibrator

    NASA Astrophysics Data System (ADS)

    Kranz, Oliver; Geckeler, Ralf D.; Just, Andreas; Krause, Michael; Osten, Wolfgang

    2015-10-01

    Electronic autocollimators are utilised versatilely for non-contact angle measurements in applications like straightness measurements and profilometry. Yet, no calibration of the angle measurement of an autocollimator has been available when both its measurement axes are engaged. Additionally, autocollimators have been calibrated at fixed distances to the reflector, although its distance may vary during the use of an autocollimator. To extend the calibration capabilities of the Physikalisch-Technische Bundesanstalt (PTB) regarding spatial angles and variable distances, a novel calibration device has been set up: the spatial angle autocollimator calibrator (SAAC). In this paper, its concept and its mechanical realisation will be presented. The focus will be on the system's mathematical modelling and its application in spatial angle calibrations. The model considers the misalignments of the SAAC's components, including the non-orthogonalities of the measurement axes of the autocollimators and of the rotational axes of the tilting unit. It allows us to derive specific measurement procedures to determine the misalignments in situ and, in turn, to correct the measurements of the autocollimators. Finally, the realisation and the results of a traceable spatial angle calibration of an autocollimator will be presented. This is the first calibration of this type worldwide.

  8. Mesoporous silica material TUD-1 as a drug delivery system.

    PubMed

    Heikkilä, T; Salonen, J; Tuura, J; Hamdy, M S; Mul, G; Kumar, N; Salmi, T; Murzin, D Yu; Laitinen, L; Kaukonen, A M; Hirvonen, J; Lehto, V-P

    2007-02-22

    For the first time the feasibility of siliceous mesoporous material TUD-1 (Technische Universiteit Delft) for drug delivery was studied. Model drug, ibuprofen, was adsorbed into TUD-1 mesopores via a soaking procedure. Characterizations with nitrogen adsorption, XRD, TG, HPLC and DSC demonstrated the successful inclusion of ibuprofen into TUD-1 host. The amount of ibuprofen adsorbed into the nanoreservoir of TUD-1 material was higher than reported for other mesoporous silica drug carriers (drug/carrier 49.5 wt.%). Drug release studies in vitro (HBSS buffer pH 5.5) demonstrated a fast and unrestricted liberation of ibuprofen, with 96% released at 210 min of the dissolution assay. The drug dissolution profile of TUD-1 material with the random, foam-like three-dimensional mesopore network and high accessibility to the dissolution medium was found to be much faster (kinetic constant k = 10.7) and more diffusion based (release constant n = 0.64) compared to a mesoporous MCM-41 material with smaller, unidirectional mesopore channels (k = 4.7, n = 0.71). Also, the mesoporous carriers were found to significantly increase the dissolution rate of ibuprofen, when compared to the pure crystalline form of the drug (k = 0.6, n = 0.96). TUD-1 was constituted as a potential drug delivery device with fast release property, with prospective applications in the formulation of poorly soluble drug compounds. PMID:17046183

  9. List of Participants

    NASA Astrophysics Data System (ADS)

    2008-11-01

    Mohab Abou ZeidInstitut des Hautes Études Scientifiques, Bures-sur-Yvette Ido AdamMax-Planck-Institut für Gravitationsphysik (AEI), Potsdam Henrik AdorfLeibniz Universität Hannover Mohammad Ali-AkbariIPM, Tehran Antonio Amariti Università di Milano-Bicocca Nicola Ambrosetti Université de Neuchâtel Martin Ammon Max-Planck-Institut für Physik, München Christopher AndreyÉcole Polytechnique Fédérale de Lausanne (EPFL) Laura AndrianopoliPolitecnico di Torino David AndriotLPTHE, Université UPMC Paris VI Carlo Angelantonj Università di Torino Pantelis ApostolopoulosUniversitat de les Illes Balears, Palma Gleb ArutyunovInstitute for Theoretical Physics, Utrecht University Davide AstolfiUniversità di Perugia Spyros AvramisUniversité de Neuchâtel Mirela BabalicChalmers University, Göteborg Foday BahDigicom Ioannis Bakas University of Patras Igor BandosUniversidad de Valencia Jose L F BarbonIFTE UAM/CSIC Madrid Till BargheerMax-Planck-Institut für Gravitationsphysik (AEI), Potsdam Marco Baumgartl Eidgenössische Technische Hochschule (ETH), Zürich James BedfordImperial College London Raphael BenichouLaboratoire de Physique Théorique, École Normale Supérieure, Paris Francesco Benini SISSA, Trieste Eric Bergshoeff Centre for Theoretical Physics, University of Groningen Alice BernamontiVrije Universiteit, Brussel Julia BernardLaboratoire de Physique Théorique, École Normale Supérieure, Paris Adel Bilal Laboratoire de Physique Théorique, École Normale Supérieure, Paris Marco Billo' Università di Torino Matthias Blau Université de Neuchâtel Guillaume BossardAlbert-Einstein-Institut, Golm Leonardo BriziÉcole Polytechnique Fédérale de Lausanne (EPFL) Johannes BroedelLeibniz Universität Hannover (AEI) Tom BrownQueen Mary, University of London Ilka BrunnerEidgenössische Technische Hochschule (ETH), Zürich Erling BrynjolfssonUniversity of Iceland Dmitri BykovSteklov Institute, Moscow and Trinity College, Dublin Joan CampsUniversitat de Barcelona

  10. [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

  11. Untersuchung der Richtwirkung der Einkopplung von ebenen Wellen in eine Leitung

    NASA Astrophysics Data System (ADS)

    Magdowski, M.; Vick, R.

    2013-07-01

    Elektrische Leitungen und Kabel stellen häufig die Haupteinfallstore für elektromagnetische Felder in die daran angeschlossenen Geräte und Systeme dar. Für die Einkopplung einer ebenen Welle kann der in eine Leitung eingekoppelte Strom unter bestimmten Voraussetzungen mit Hilfe der Leitungstheorie sehr effizient bestimmt werden. Er hängt dabei von den Abmessungen der Leitung, den Leitungsabschlüssen sowie der Amplitude, der Wellenlänge und der Einfallsrichtung der ebenen Welle ab. In dieser Arbeit wird die Abhängigkeit der Einkopplung von der Einfallsrichtung näher untersucht. Dazu werden Richtdiagramme der Einkopplung berechnet, dargestellt und hinsichtlich der mittleren und maximalen Einkopplung über alle Einfallsrichtungen und Polarisationen ausgewertet. Die Ergebnisse werden genutzt, um die maximale Direktivität der Einkopplung in eine Leitung zu bestimmen. Fasst man die Einkopplung externer Felder in eine Leitung als einen Störfestigkeitstest auf, so kann die maximale Direktivität benutzt werden, um einen Vergleich zwischen unterschiedlichen Messumgebungen wie Absorberhallen und Modenverwirbelungskammern herzustellen.

  12. Magnetisches Tracking für die Navigation mit dem da Vinci® Surgical System

    NASA Astrophysics Data System (ADS)

    Nickel, Felix; Wegner, Ingmar; Kenngott, Hannes; Neuhaus, Jochen; Müller-Stich, Beat P.; Meinzer, Hans-Peter; Gutt, Carsten N.

    In dieser Studie wurde untersucht ob in einem typischen OP-Aufbau mit dem da Vinci® Telemanipulator elektromagnetisches Tracking für die Realisation eines Navigationssystems eingesetzt werden kann. Hierfür wurde in einem realen OP-Aufbau untersucht, wie stark metallische und ferromagnetisch wirksame Objekte wie Operationstisch und Telemanipulator das elektromagnetische Feld des Trackingsystems beeinflussen. Die Ergebnisse zeigen, dass der Telemanipulator nur unwesentlich die Störung des Magnetfeldes durch den OP-Tisch verstärkt. Insbesondere die Bewegung der Instrumente im Trackingvolumen verursachte keine zusätzliche relevante Störung des Magnetfeldes. Bei Begrenzung des Trackingvolumens auf eine Länge von 190 mm, Höhe von 200mm und Breite von 400 mm war der maximale Fehler in diesem Bereich an allen Messpunkten kleiner 10 mm. Der Einsatz von elektromagnetischem Tracking für die Navigation mit dem da Vinci® Surgical System ist somit in einem begrenzten Arbeitsvolumen mit hinreichender Genauigkeit möglich.

  13. Ray effects in the discrete-ordinate solution for surface radiation exchange

    NASA Astrophysics Data System (ADS)

    Liou, B.-T.; Wu, C.-Y.

    A study of the application of the discrete-ordinate method (DOM) with remedy for the ray effects to the solution of surface radiation exchange is presented in this paper. The remedy for the ray effects is achieved by dividing the radiative intensity into the attenuated incident and the medium emitting components. To demonstrate the application of the technique, this work considers radiative heat transfer in a two-dimensional cylindrical enclosure filled with a nearly transparent medium. The results obtained by the present DOM are in excellent agreement with those by the radiosity/irradiation method. Zusammenfassung In der Arbeit wird ein Weg aufgezeigt, wie die Störstrahlungseffekte bei Anwendung der Methode der diskreten Ordinaten auf die Berechnung des Energietausches zwischen Oberflächenstrahlern vermieden werden können. Dies läßt sich durch Aufspaltung der Strahlungsintensität in die abgeschwächte einfallende und die vom Medium emittierte Komponente erreichen. Als Beispiel für die Anwendung dieses Verfahrens dient der Wärmeaustausch durch Strahlung in einem zweidimensionalen zylindrischen Behältnis, das mit einem nahezu transparenten Medium befüllt ist. Die mit der modifizierten Methode erhaltenen Ergebnisse stimmen ausgezeichnet mit jenen nach dem klassischen Brutto-Verfahren überein.

  14. PREFACE: 11th International Conference on Electrorheological Fluids and Magnetorheological Suspensions

    NASA Astrophysics Data System (ADS)

    Odenbach, Stefan; Borin, Dmitry

    2009-07-01

    Materials with properties controllable by external fields become more and more important for modern product design. Magnetorheological suspensions, electrorheological fluids and ferrofluids are classical examples for such smart materials exhibiting magnetic or electric field dependent properties. Their development over the past 60 years has shown how complex research and development of fluids with tailored properties can be. The demands of potential applications are the driving force for the synthesis of new fluids. The changes in the synthetic process and the composition of the fluids based on an increasing understanding of the relevant microscopic processes leads to certain macroscopic properties of the material. Only intense cooperation between basic and application oriented research, synthesis, characterisation, theory and application design can finally lead to fluids suitable for the envisaged use. The International Conferences on Electrorheological Fluids and Magnetorheological Suspensions have provided over more than 20 years a platform for interdisciplinary discussions strengthening the scientific progress in the field. Besides being a forum for scientific exchange about recent developments in electro- and magnetorheological fluids. The 11th International Conference on Electrorheological Fluids and Magnetorheological Suspensions (ERMR08) which has been organized by the chair of Magnetofluiddynamics at the Technische Universität Dresden in August 2008 in Dresden has continued this fruitful tradition. With more than 180 participants from 24 different countries it has been the largest ERMR meeting during the last decade - a tendency showing the high potential and promising development of the field of electrically and magnetically controllable fluids. A significant proportion of the participants were PhD students, a fact that also highlights the sustainability of the field. In total 85 oral presentations - including 8 plenary talks - and 81 posters were

  15. PREFACE: The International Conference on Highly Frustrated Magnetism HFM2008

    NASA Astrophysics Data System (ADS)

    Eremin, Ilya; Brenig, Wolfram; Kremer, Reinhard; Litterst, Jochen

    2009-01-01

    The International Conference on Highly Frustrated Magnetism 2008 (HFM2008) took place on 7-12 September 2008 at the Technische Universität Carolo-Wilhelmina zu Braunschweig, Germany. This conference was the fourth event in a series of meetings, which started in Waterloo, Canada (HFM 2000), followed by the second one in Grenoble, France (HFM 2003), and the third meeting in Osaka, Japan (HFM 2006). HFM2008 attracted more than 220 participants from all over the world. The number of participants of the HFM conference series has been increasing steadily, from about 80 participants at HFM 2000, to 120 participants at HFM 2003, and 190 participants at HFM 2006, demonstrating that highly frustrated magnetism remains a rapidly growing area of research in condensed matter physics. At the end of HFM2008 it was decided that the next International Conference on Highly Frustrated Magnetism will be held in Baltimore, USA in 2010. HFM2008 saw four plenary talks by R Moessner, S Nakatsuji, S-W Cheong, and S Sachdev, 18 invited presentations, 30 contributed talks and about 160 poster presentations from all areas of frustrated magnetism. The subjects covered by the conference included: Kagome systems Itinerant frustrated systems Spinels and pyrochlore materials Triangular systems Unconventional order and spin liquids Chain systems Chain systems Novel frustrated systems This volume of Journal of Physics: Conference Series contains the proceedings of HFM2008 with 83 papers that provide a scientific record of the scientific topics covered by the conference. All articles have been refereed by experts in the field. It is our hope that the reader will enjoy and profit from the HFM2008 Proceedings. Ilya Eremin Proceedings Editor Wolfram Brenig, Reinhard Kremer, and Jochen Litterst Co-Editors International Advisory Board L Balents (USA) F Becca (Italy) S Bramwell (UK) P Fulde (Germany) B D Gaulin (Canada) J E Greedan (Canada) A Harrison (France) Z Hiroi (Japan) H Kawamura (Japan) A Keren

  16. Committees

    NASA Astrophysics Data System (ADS)

    2012-11-01

    Leadership Team of the IAHR Committee for Hydraulic Machinery and Systems Eduard EGUSQUIZA, UPC Barcelona, Spain, Chair François AVELLAN, EPFL-LMH, Switzerland, Past Chair Richard K FISHER, Voith Hydro Inc., USA, Past Chair Fidel ARZOLA, Edelca, Venezuela Michel COUSTON, Alstom Hydro, France Niklas DAHLBÄCKCK, Vatenfall, Sweden Normand DESY, Andritz VA TECH Hydro Ltd., Canada Chisachi KATO, University of Tokyo, Japan Andrei LIPEJ, Turboinstitut, Slovenija Torbjørn NIELSEN, NTNU, Norway Romeo SUSAN-RESIGA, 'Politehnica' University Timisoara, Romania Stefan RIEDELBAUCH, Stuggart University, Germany Albert RUPRECHT, Stuttgart University, Germany Qing-Hua SHI, Dong Fang Electrical Machinery Co., China Geraldo TIAGO, Universidade Federal de Itajubá, Brazil International Advisory Committee Shouqi YUAN (principal) Jiangsu University China QingHua SHI (principal) Dong Fang Electrical Machinery Co. China Fidel ARZOLA EDELCA Venezuela Thomas ASCHENBRENNER Voith Hydro GmbH & Co. KG Germany Anton BERGANT Litostroj Power doo Slovenia B C BHAOYAL Research & Technology Centre India Hermod BREKKE NTNU Norway Stuart COULSON Voith Hydro Inc. USA Paul COOPER Fluid Machinery Research Inc USA V A DEMIANOV Power Machines OJSC Russia Bart van ESCH Technische Universiteit Eindhoven Netherland Arno GEHRER Andritz Hydro Graz Austria Akira GOTO Ebara Corporation Japan Adiel GUINZBURG The Boeing Company USA D-H HELLMANN KSB AG Germany Ashvin HOSANGADI Combustion Research and Flow Technology USA Byung-Sun HWANG Korea Institute of Material Science Korea Toshiaki KANEMOTO Kyushu Institute of Technology Japan Mann-Eung KIM Korean Register of Shipping Korea Jiri KOUTNIK Voith Hydro GmbH & Co. KG Germany Jinkook LEE Eaton Corporation USA Young-Ho LEE Korea Maritime University Korea Woo-Seop LIM Hyosung Goodsprings Inc Korea Jun MATSUI Yokohama National University Japan Kazuyoshi Mitsubishi H I Ltd, Japan MIYAGAWA Christophe NICOLET Power Vision Engineering Srl Switzerland Maryse PAGE Hydro

  17. Review of access, licenses and understandability of open datasets used in hydrology research

    NASA Astrophysics Data System (ADS)

    Falkenroth, Esa; Arheimer, Berit; Lagerbäck Adolphi, Emma

    2015-04-01

    The amount of open data available for hydrology research is continually growing. In the EU-funded project SWITCH-ON (Sharing Water-related Information to Tackle Changes in the Hydrosphere - for Operational Needs), we are addressing water concerns by exploring and exploiting the untapped potential of these new open data. This work is enabled by many ongoing efforts to facilitate the use of open data. For instance, a number of portals (such as the GEOSS Portal and the INSPIRE community geoportal) provide the means to search for such open data sets and open spatial data services. However, in general, the systematic use of available open data is still fairly uncommon in hydrology research. Factors that limits (re)usability of a data set include: (1) accessibility, (2) understandability and (3) licences. If you cannot access the data set, you cannot use if for research. If you cannot understand the data set you cannot use it for research. Finally, if you are not permitted to use the data, you cannot use it for research. Early on in the project, we sent out a questionnaire to our research partners (SMHI, Universita di Bologna, University of Bristol, Technische Universiteit Delft and Technische Universitaet Wien) to find out what data sets they were planning to use in their experiments. The result was a comprehensive list of useful open data sets. Later, this list of data sets was extended with additional information on data sets for planned commercial water-information products and services. With the list of 50 common data sets as a starting point, we reviewed issues related to access, understandability and licence conditions. Regarding access to data sets, a majority of data sets were available through direct internet download via some well-known transfer protocol such as ftp or http. However, several data sets were found to be inaccessible due to server downtime, incorrect links or problems with the host database management system. One possible explanation for this

  18. IN MEMORIAM: Hermann Anton Haus, 1925 2003

    NASA Astrophysics Data System (ADS)

    2004-08-01

    Photograph Hermann Anton Haus, an Institute Professor at the Massachusetts Institute of Technology (MIT), was to have been a Keynote Speaker at the Fluctuations and Noise in Photonics and Quantum Optics Conference, from which the papers in this special issue derive. Sadly, on May 21, 2003 - less than two weeks before the conference - Professor Haus succumbed to a heart attack after arriving home in Lexington, Massachusetts, from his regular, 15-mile commute by bicycle from MIT. He was 77. Throughout his lengthy and illustrious career, Professor Haus had repeatedly and very successfully addressed problems of fluctuations and noise, with special focus on the fundamental issues that arise in quantum optics. To honour Professor Haus' legacy to our technical community, this special issue of Journal of Optics B: Quantum and Semiclassical Optics is dedicated to his memory. Professor Haus was born in Ljubljana, Slovenia, in the former Yugoslavia, on 8 August 1925. After attending the Technische Hochschule, Graz, and the Technische Hochschule, Wien, in Austria, he received his Bachelor of Science degree from Union College in Schenectady, New York in 1949. In 1951, he graduated from Rensselaer Polytechnic Institute with a Master of Science in Electrical Engineering, and came to MIT, where he earned his Doctorate of Science and joined the faculty in 1954. He was promoted to Associate Professor in 1958, to Professor in 1962, and to Elihu Thomson Professor in 1973. In 1986, he was conferred the honour of Institute Professor. Professor Haus had a lifelong fascination with noise. While still an undergraduate at Union College, he became aware of Norbert Wiener's theories of statistical phenomena - the new mathematics needed to understand and quantify the random fluctuations we refer to as noise. So it was that noise theory formed the core of Professor Haus' research during the 1950s: noise in electron beams, noise in microwave amplifiers, and noise in amplifier cascades. Two of

  19. Chemical management and control strategies: experiences from the GTZ pilot project on chemical safety in Indonesian small and medium-sized enterprises.

    PubMed

    Tischer, M; Scholaen, S

    2003-10-01

    In 1998 the Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) launched the Convention Project on Chemical Safety in developing countries. The project aims to support developing countries in the implementation of the Rotterdam and Stockholm Conventions, create human resources and institutional capacities and to demonstrate via pilot measures how chemical safety in the partner countries can be improved and sustainably implemented in line with international standards. With this objective the development of a Chemical Management Guide (CM Guide) for small and medium-sized enterprises in developing countries has been initiated. The guide describes a step-by-step approach which is based on identifying 'hot-spots' as a first step, and making a chemical inventory as a second step. The third step is the continuous improvement of chemical management. In total, there are six tools that aim to support the chemical management process: basic concepts for risk assessment; description of control approaches; using material safety data sheets (MSDSs); risk phrases for hazardous substances; safety phrases for hazardous substances; symbols used for labelling hazardous substances. In the course of the test-implementation of the CM Guide in Indonesia, it was found that MSDSs were not available in most of the smaller companies. In contrast, medium-sized and larger companies do have more MSDSs available. It was also found that the way to engage the minds of company owners and managers is with economic arguments related to the loss, waste and expiry of materials, and quality standards expected from importing countries. PMID:14530183

  20. Development of a system for neutron radiography and tomography

    NASA Astrophysics Data System (ADS)

    Mühlbauer, Martin J.; Calzada, Elbio; Schillinger, Burkhard

    2005-04-01

    Neutron radiography and tomography are getting more and more popular. Since they use the white thermal neutron spectrum, they are especially feasible even at small neutron sources, where the flux is too low for efficient scattering experiments requiring monochromatization of the beam. High-end tomography systems require the investment of several ten thousand Euros, with the costs often hindering the initiative for a new tomography setup. Based on the experiences gathered at Technische Universitaet Muenchen, we developed a cheaper system based on standard components that cannot compete with the sensitivity of a high-grade system, but is perfectly capable of doing neutron radiography and tomography. The system is meant as a startup construction kit for initiating tomography programs even at small neutron sources. The system is built from scratch, enabling the user to gain an understanding for the influence of each component on the image results. With the experience thus gained, he should be able to design his next and more advanced system by himself. To keep the whole system simple and cheap (the price should reach only a few percent of a high-end system), standard parts are used whenever possible, and all components are designed in such a way that they can be built without special equipment. Public domain and freeware software is used for data processing. Such a system is being built at FRM2 in Garching within the scope of a master thesis. After completion, a website will be installed with descriptions, diagrams and software for building and operating the system. Both hardware and software are discussed.

  1. Providing radiometric traceability for the calibration home base of DLR by PTB

    SciTech Connect

    Taubert, D. R.; Hollandt, J.; Sperfeld, P.; Pape, S.; Hoepe, A.; Hauer, K.-O.; Gege, P.; Schwarzmaier, T.; Lenhard, K.; Baumgartner, A.

    2013-05-10

    A dedicated calibration technique was applied for the calibration of the spectral radiance transfer standard (RASTA) of the German Aerospace Center (DLR) at the Physikalisch-Technische Bundesanstalt (PTB), consisting of two independent but complementing calibration procedures to provide redundancy and smallest possible calibration uncertainties. Procedure I included two calibration steps: In a first step the optical radiation source of RASTA, an FEL lamp, was calibrated in terms of its spectral irradiance E{sub {lambda}}({lambda}) in the wavelength range from 350 nm to 2400 nm using the PTB Spectral Irradiance Calibration Equipment (SPICE), while in a second step the spectral radiance factor {beta}{sub 0 Degree-Sign :45 Degree-Sign }({lambda}) of the RASTA reflection standard was calibrated in a 0 Degree-Sign :45 Degree-Sign -viewing geometry in the wavelength range from 350 nm to 1700 nm at the robot-based gonioreflectometer facility of PTB. The achieved relative standard uncertainties (k= 1) range from 0.6 % to 3.2 % and 0.1 % to 0.6 % respectively. Procedure II was completely independent from procedure I and allowed to cover the entire spectral range of RASTA from 350 nm to 2500 nm. In the second procedure, the 0 Degree-Sign :45 Degree-Sign -viewing geometry spectral radiance L{sub {lambda},0 Degree-Sign :45 Degree-Sign }({lambda}) of RASTA was directly calibrated at the Spectral Radiance Comparator Facility (SRCF) of PTB. The relative uncertainties for this calibration procedure range from 0.8 % in the visible up to 7.5 % at 2500 nm (k= 1). In the overlapping spectral range of both calibration procedures the calculated spectral radiance L{sub {lambda},0 Degree-Sign :45 Degree-Sign ,calc}({lambda}) from procedure I is in good agreement with the direct measurement of procedure II, i.e. well within the combined expanded uncertainties (k= 2) of both procedures.

  2. Capillary blood islet autoantibody screening for identifying pre-type 1 diabetes in the general population: design and initial results of the Fr1da study

    PubMed Central

    Raab, Jennifer; Haupt, Florian; Scholz, Marlon; Matzke, Claudia; Warncke, Katharina; Lange, Karin; Assfalg, Robin; Weininger, Katharina; Wittich, Susanne; Löbner, Stephanie; Beyerlein, Andreas; Nennstiel-Ratzel, Uta; Lang, Martin; Laub, Otto; Dunstheimer, Desiree; Bonifacio, Ezio; Achenbach, Peter; Winkler, Christiane; Ziegler, Anette-G

    2016-01-01

    Introduction Type 1 diabetes can be diagnosed at an early presymptomatic stage by the detection of islet autoantibodies. The Fr1da study aims to assess whether early staging of type 1 diabetes (1) is feasible at a population-based level, (2) prevents severe metabolic decompensation observed at the clinical manifestation of type 1 diabetes and (3) reduces psychological distress through preventive teaching and care. Methods and analysis Children aged 2–5 years in Bavaria, Germany, will be tested for the presence of multiple islet autoantibodies. Between February 2015 and December 2016, 100 000 children will be screened by primary care paediatricians. Islet autoantibodies are measured in capillary blood samples using a multiplex three-screen ELISA. Samples with ELISA results >97.5th centile are retested using reference radiobinding assays. A venous blood sample is also obtained to confirm the autoantibody status of children with at least two autoantibodies. Children with confirmed multiple islet autoantibodies are diagnosed with pre-type 1 diabetes. These children and their parents are invited to participate in an education and counselling programme at a local diabetes centre. Depression and anxiety, and burden of early diagnosis are also assessed. Results Of the 1027 Bavarian paediatricians, 39.3% are participating in the study. Overall, 26 760 children have been screened between February 2015 and November 2015. Capillary blood collection was sufficient in volume for islet autoantibody detection in 99.46% of the children. The remaining 0.54% had insufficient blood volume collected. Of the 26 760 capillary samples tested, 0.39% were positive for at least two islet autoantibodies. Discussion Staging for early type 1 diabetes within a public health setting appears to be feasible. The study may set new standards for the early diagnosis of type 1 diabetes and education. Ethics dissemination The study was approved by the ethics committee of Technische Universit

  3. Final report on regional comparison EURAMET.PR-K4: luminous flux

    NASA Astrophysics Data System (ADS)

    Lindemann, Matthias; Maass, Robert; Sauter, Georg

    2015-01-01

    This report describes the EURAMET comparison for luminous flux carried out at 12 participating national metrology laboratories (NMIs). More than a decade ago, the CCPR initialised a key comparison for luminous flux denoted as CCPR K4. The reference value CCPR-KCRV for luminous flux is maintained since that time by the participants of that early CCPR comparison. Beside the pilot laboratory, the Physikalisch-Technische Bundesanstalt (PTB), two additional former participants acted as link laboratories for this EURAMET-Key-Comparison. The luminous flux CCPR-KCRV, maintained at the link laboratories and transferred by batches of incandescent lamps, was used to evaluate a reference value (EURAMET-RV) at the pilot laboratory as a weighted luminous flux average for this comparison. Finally, the realized or preserved luminous flux values of all other participants were compared with the EURAMET-RV in a star-type comparison at the pilot with batches of three to six lamps of various types. The DOEs of the values of the participants with respect to the reference value and mutually with all other luminous flux values are evaluated and published in the report together with the associated uncertainties. The deviations from the EURAMET-RV and hence from the CCPR-KCRV are within the declared expanded uncertainties for all participants. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  4. Final report on regional comparison EURAMET.PR-K3.a: Luminous intensity

    NASA Astrophysics Data System (ADS)

    Sperling, A.; Sauter, G.; Lindner, D.; Eltmann, M.

    2014-01-01

    This report describes the EURAMET comparison for luminous intensity carried out at 16 participating national metrology laboratories (NMIs). More than a decade ago, the CCPR initialised a key comparison for luminous intensity denoted as CCPR-K3.a. The reference value CCPR-KCRV for luminous intensity has been maintained since that time by the participants of that early CCPR comparison. Beside the pilot laboratory, the Physikalisch-Technische Bundesanstalt (PTB), two additional former participants acted as link laboratories for this EURAMET Key Comparison. The luminous intensity CCPR-KCRV, maintained at the link laboratories and transferred by batches of incandescent lamps, was used to evaluate a reference value (EURAMET-RV) at the pilot laboratory as a weighted luminous intensity average for this comparison. Finally, the realized or preserved luminous intensity values of all other participants were compared with the EURAMET-RV in a star-type comparison at the pilot with batches of three to eight lamps of various types. The DOEs of the values of the participants with respect to the reference value and mutually with all other luminous intensity values are evaluated and published in the report together with the associated uncertainties. The deviations from the EURAMET-RV and hence from the CCPR-KCRV are within the declared expanded uncertainties for all participants. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCPR, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  5. Broad-band efficiency calibration of ITER bolometer prototypes using Pt absorbers on SiN membranes

    NASA Astrophysics Data System (ADS)

    Meister, H.; Willmeroth, M.; Zhang, D.; Gottwald, A.; Krumrey, M.; Scholze, F.

    2013-12-01

    The energy resolved efficiency of two bolometer detector prototypes for ITER with 4 channels each and absorber thicknesses of 4.5 μm and 12.5 μm, respectively, has been calibrated in a broad spectral range from 1.46 eV up to 25 keV. The calibration in the energy range above 3 eV was performed against previously calibrated silicon photodiodes using monochromatized synchrotron radiation provided by five different beamlines of Physikalische Technische Bundesanstalt at the electron storage rings BESSY II and Metrology Light Source in Berlin. For the measurements in the visible range, a setup was realised using monochromatized halogen lamp radiation and a calibrated laser power meter as reference. The measurements clearly demonstrate that the efficiency of the bolometer prototype detectors in the range from 50 eV up to ≈6 keV is close to unity; at a photon energy of 20 keV the bolometer with the thick absorber detects 80% of the photons, the one with the thin absorber about 50%. This indicates that the detectors will be well capable of measuring the plasma radiation expected from the standard ITER scenario. However, a minimum absorber thickness will be required for the high temperatures in the central plasma. At 11.56 keV, the sharp Pt-L3 absorption edge allowed to cross-check the absorber thickness by fitting the measured efficiency to the theoretically expected absorption of X-rays in a homogeneous Pt-layer. Furthermore, below 50 eV the efficiency first follows the losses due to reflectance expected for Pt, but below 10 eV it is reduced further by a factor of 2 for the thick absorber and a factor of 4 for the thin absorber. Most probably, the different histories in production, storage, and operation led to varying surface conditions and additional loss channels.

  6. TUM Critical Zone Observatory, Germany

    NASA Astrophysics Data System (ADS)

    Völkel, Jörg; Eden, Marie

    2014-05-01

    Founded 2011 the TUM Critical Zone Observatory run by the Technische Universität München and partners abroad is the first CZO within Germany. TUM CZO is both, a scientific as well as an education project. It is a watershed based observatory, but moving behind this focus. In fact, two mountainous areas are integrated: (1) The Ammer Catchment area as an alpine and pre alpine research area in the northern limestone Alps and forelands south of Munich; (2) the Otter Creek Catchment in the Bavarian Forest with a crystalline setting (Granite, Gneiss) as a mid mountainous area near Regensburg; and partly the mountainous Bavarian Forest National Park. The Ammer Catchment is a high energy system as well as a sensitive climate system with past glacial elements. The lithology shows mostly carbonates from Tertiary and Mesozoic times (e.g. Flysch). Source-to-sink processes are characteristic for the Ammer Catchment down to the last glacial Ammer Lake as the regional erosion and deposition base. The consideration of distal depositional environments, the integration of upstream and downstream landscape effects are characteristic for the Ammer Catchment as well. Long term datasets exist in many regards. The Otter Creek catchment area is developed in a granitic environment, rich in saprolites. As a mid mountainous catchment the energy system is facing lower stage. Hence, it is ideal comparing both of them. Both TUM CZO Catchments: The selected catchments capture the depositional environment. Both catchment areas include historical impacts and rapid land use change. Crosscutting themes across both sites are inbuilt. Questions of ability to capture such gradients along climosequence, chronosequence, anthroposequence are essential.

  7. Quantitative comparison between PGNAA measurements and MCNP calculations in view of the characterization of radioactive wastes in Germany and France

    NASA Astrophysics Data System (ADS)

    Mauerhofer, E.; Havenith, A.; Carasco, C.; Payan, E.; Kettler, J.; Ma, J. L.; Perot, B.

    2013-04-01

    The Forschungszentrum Jülich GmbH (FZJ), together with the Aachen University Rheinisch-Westfaelische Technische Hochschule (RWTH) and the French Alternative Energies and Atomic Energy Commission (CEA Cadarache) are involved in a cooperation aiming at characterizing toxic and reactive elements in radioactive waste packages by means of Prompt Gamma Neutron Activation Analysis (PGNAA) [1]. The French and German waste management agencies have indeed defined acceptability limits concerning these elements in view of their projected geological repositories. A first measurement campaign was performed in the new Prompt Gamma Neutron Activation Analysis (PGNAA) facility called MEDINA, at FZJ, to assess the capture gamma-ray signatures of some elements of interest in large samples up to waste drums with a volume of 200 liter. MEDINA is the acronym for Multi Element Detection based on Instrumental Neutron Activation. This paper presents MCNP calculations of the MEDINA facility and quantitative comparison between measurement and simulation. Passive gamma-ray spectra acquired with a high purity germanium detector and calibration sources are used to qualify the numerical model of the crystal. Active PGNAA spectra of a sodium chloride sample measured with MEDINA then allow for qualifying the global numerical model of the measurement cell. Chlorine indeed constitutes a usual reference with reliable capture gamma-ray production data. The goal is to characterize the entire simulation protocol (geometrical model, nuclear data, and postprocessing tools) which will be used for current measurement interpretation, extrapolation of the performances to other types of waste packages or other applications, as well as for the study of future PGNAA facilities.

  8. Status of the nanometer comparator at PTB

    NASA Astrophysics Data System (ADS)

    Fluegge, Jens; Koening, Rainer G.

    2001-10-01

    Due to increasing demands on the photolithography of integrated circuits and the progress of interferometric linear encoders, length measurement systems with a reproducibility under 3 nm are used in industry today, whereas the connection to the unit of length exhibits an uncertainty of about 25 nm. To resolve this problem a new one dimensional length comparator, the nanometer comparator, was developed in a cooperation between the Physikalisch-Technische Bundesanstalt (PTB), the Dr. Johannes Heidenhain GmbH and Werth Me#technik GmbH. The nanometer comparator will be able to perform one dimensional calibrations of photo masks, line-graduation scales, incremental linear encoders and laser interferometers in one axis up to a maximum length of 610 mm. To ensure the highest level of measurement performance, the interferometer is completely located in vacuum using metal bellows, whilst the calibration objects can be mounted under atmospheric conditions. The interferometer set-up compensates the dilatation and the bending of the granite base and minimizes the measurement circle of the comparator. This will minimize the influence of thermal and mechanical distortions. The interferometer design can be used with a heterodyne or a homodyne signal detection electronics. Due to their high power dissipation, the laser is arranged far apart from the comparator and light is fed to the interferometers by means of glass fibers. The light source is a frequency-doubled Nd:YAG laser frequency stabilized by an iodine absorption line. Different measuring systems for the structure localization can be attached to an universal sensor carrier on a solid bridge above the measuring carriage. Incremental reading heads and two photoelectric microscopes are now available for this purpose.

  9. The in-flight blackbody calibration system for the GLORIA interferometer on board an airborne research platform

    NASA Astrophysics Data System (ADS)

    Olschewski, F.; Ebersoldt, A.; Friedl-Vallon, F.; Gutschwager, B.; Hollandt, J.; Kleinert, A.; Monte, C.; Piesch, C.; Preusse, P.; Rolf, C.; Steffens, P.; Koppmann, R.

    2013-06-01

    traceable to the International Temperature Scale (ITS-90) at the Physikalisch-Technische Bundesanstalt (PTB), the national metrology institute of Germany.

  10. The in-flight blackbody calibration system for the GLORIA interferometer on board an airborne research platform

    NASA Astrophysics Data System (ADS)

    Olschewski, F.; Ebersoldt, A.; Friedl-Vallon, F.; Gutschwager, B.; Hollandt, J.; Kleinert, A.; Monte, C.; Piesch, C.; Preusse, P.; Rolf, C.; Steffens, P.; Koppmann, R.

    2013-11-01

    traceable to the International Temperature Scale (ITS-90) at the Physikalisch-Technische Bundesanstalt (PTB), the national metrology institute of Germany.