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  • 1
    Publication Date: 2018-12-01
    Description: Electronic heterodyne moire deflectometry and electronic heterodyne holographic interferometry are compared as methods for the accurate measurement of refractive index and density change distributions of phase objects. Experimental results are presented to show that the two methods have comparable accuracy for measuring the first derivative of the interferometric fringe shift. The phase object for the measurements is a large crystal of KD P, whose refractive index distribution can be changed accurately and repeatably for the comparison. Although the refractive index change causes only about one interferometric fringe shift over the entire crystal, the derivative shows considerable detail for the comparison. As electronic phase measurement methods, both methods are very accurate and are intrinsically compatible with computer controlled readout and data processing. Heterodyne moire is relatively inexpensive and has high variable sensitivity. Heterodyne holographic interferometry is better developed, and can be used with poor quality optical access to the experiment.
    Keywords: INSTRUMENTATION AND PHOTOGRAPHY
    Type: SAE PAPER 851896
    Format: text
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  • 2
    Publication Date: 2013-08-31
    Description: Effects of spherical aberrations of the mirror used in the moire system on the angular resolution of the system are investigated. It is shown that the spherical aberrations may reduce significantly the performance of the conventional moire deflectometer. However, due to the heterodyne procedure, this is not the case with the heterodyne moire system. A moire system with a constant speed moving grating is demonstrated. It is shown that the system readout is linear and the system does not need calibration. In addition, the repeatability of the measurements is improved in this system as compared to the sinusoidally moving grating setup. The problem of the photographic plates alignment is solved by using a mechanical system in which the plate is held firmly throughout the experiment and accurately replaced after removing for photographic processing. The effect of a circular detector's aperture size on readout was tested. It is shown that the spatial phase variations, observed when scanning along a straight moire fringe, may considerably be reduced. At present we may say that both the on-line and the deferred heterodyne moire techniques may reliably be used. The errors of phase readings are 1 deg and 5 deg for the on-line and deferred methods. The total error due to subtraction of two readings at each position is, therefore, 1.4 deg and 7 deg, respectively. Further research for improving the deferred system is suggested.
    Keywords: OPTICS
    Type: NAS 1.26:182982 , NASA-CR-182982
    Format: application/pdf
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  • 3
    Publication Date: 2013-08-31
    Description: Electronic heterodyne moire deflectometry and electronic heterodyne holographic interferometry are compared as methods for the accurate measurement of refractive index and density change distributions of phase objects. Experimental results are presented to show that the two methods have comparable accuracy for measuring the first derivative of the interferometric fringe shift. The phase object for the measurements is a large crystal of KD*P, whose refractive index distribution can be changed accurately and repeatably for the comparison. Although the refractive index change causes only about one interferometric fringe shift over the entire crystal, the derivative shows considerable detail for the comparison. As electronic phase measurement methods, both methods are very accurate and are intrinsically compatible with computer controlled readout and data processing. Heterodyne moire is relatively inexpensive and has high variable sensitivity. Heterodyne holographic interferometry is better developed, and can be used with poor quality optical access to the experiment.
    Keywords: INSTRUMENTATION AND PHOTOGRAPHY
    Type: NASA-TM-87071 , NAS 1.15:87071 , E-2643
    Format: application/pdf
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  • 4
    Publication Date: 2013-08-31
    Description: Effects of diffraction and nonlinear photographic emulsion characteristics on the performance of deferred electronic heterodyne moire deflectometry are investigated. The deferred deflectometry is used for measurements of nonsteady phase objects where it is difficult to complete the analysis of the field in real time. The sensitivity, accuracy and resolution of the system are calculated and it is shown that they are weakly affected by diffraction and by nonlinear recording. The feactures of the system are significantly improved compared with the conventional deferred intensity moire technique, and are comparable with the online heterodyne moire. The system was evaluated experimentally by deferred measurements of the refractive index gradients of a weak phase object consisting of a large KD*P crystal. This was done by photographing the phase object through a Ronchi grating and analyzing the tranparency with the electronic heterodyne readout system. The results are compared with the measurements performed on the same phase object with online heterodyne moire deflectometry and with heterodyne holographic interferometry methods. Some practical considerations for system improvement are discussed.
    Keywords: ELECTRONICS AND ELECTRICAL ENGINEERING
    Type: NASA-CR-181134 , NAS 1.26:181134
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  • 5
    Publication Date: 2013-08-31
    Description: The results are summarized of the computerized (DORCA) analyses of a number of NASA/Non-NASA and DoD payload mission models that have been used in conjunction with studies of the Space Transportation System (STS). The first analysis performed was on the 1971 NASA/Non-NASA and DoD mission models. Subsequent to that, analyses of the June 1972 excursion to the 1971 NASA/Non-NASA mission models were performed. The mission models have two basic versions; i.e., one employing expendable payloads and another employing a best mix of expendable and reusable payloads. Both versions of the models have the same payload deployment schedule. However, in the best mix version, payloads are retrieved from orbit and whenever possible, refurbished payloads are deployed. The analyses were performed to determine the relative merits to different Tug configurations and of Tug combinations employed in several phased development schemes.
    Keywords: SPACE VEHICLES
    Type: NASA-CR-138141 , ATR-74(7336)-2
    Format: application/pdf
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  • 6
    Publication Date: 2017-01-25
    Description: Historically Switzerland is characterized by numerous small towns. During the twentieth century, the image of Swiss cities has changed: the expansion of the city has reached the limits of administrative urban borders, penetrating in peripheral locations. The main reasons concern not only the territorial environment, but also the possibility to support public services and public investments. Currently, urban agglomerations include dozens of municipalities and this is seen as a virtuous strategy to provide basic public services and utilities in peripheral areas. Swiss federalism has fostered the development of a large number of small and medium sized cities. This creates the conditions for polycentric and decentralized settlements. At this stage of the territorial and institutional transformation, the understanding of different municipalities? roles is essential: the ?work? and ?live? functions are spread irregularly throughout the territory. Some core cities are traditionally business locations but the progressive urbanization has enhanced the attractiveness of the belt municipalities, for both residential and business purposes. We try to identify the different functions and relations between 47 agglomerated municipalities in southern Switzerland (Ticino), using a territorial agent based model. The analysis focus on four analytical dimensions: economic competitiveness, attractiveness, openness and social equality. Our research adopts a bottom up approach to urban systems, considering the agglomeration mechanism and effects of different regional and urban policies. Urban residential dynamics are the result of simultaneous household?s choices; thus, no program can be planned, without the ability to understand and predict the individual decisions in the short and long term. Recently, agent based models (ABMs) have been proposed in order to support urban policy makers. Simulating the individual actions of diverse agents on a real city and measuring the resulting system behaviour and outcomes over time, they provide a good test bed for evaluating the impact of different policies Our analysis starts from the micro level at the smallest territorial unit (municipalities). The database is created merging the Swiss official secondary data for one reference year (2011) with Eurostat and OECD Regpat. The model, linking territorial characteristics and agents, simulates the single location choices and formation of urban development patterns, which are influenced by residential and industrial agglomeration forces and policy interventions. The results highlight that the understanding of municipalities? functions on the territory appears to be essential for designing a solid institutional agglomeration (or city). From a methodological point of view, we contribute to improve the application of territorial ABMs. Finally, our results provide a robust base to evaluate in a dynamic way various political interventions, in order to ensure a sustainable development of the agglomeration and the surrounding territories.
    Keywords: C63 ; R12 ; R14 ; ddc:330 ; urban agglomeration ; urban policy evaluation ; Agent Based Models
    Repository Name: EconStor: OA server of the German National Library of Economics - Leibniz Information Centre for Economics
    Language: English
    Type: doc-type:conferenceObject
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  • 7
    Publication Date: 2016-03-11
    Type: NACA-RM-E6K01
    Format: application/pdf
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  • 8
    Publication Date: 2016-04-21
    Description: Die Pisa-Ergebnisse haben Entscheidungen zum Ausbau der frühkindlichen Förderung ausgelöst. Damit verbunden sind höhere Anforderungen an die Kompetenzprofile der Erzieher/innen, der Qualifizierungsbedarf steigt. In Deutschland existiert jedoch ein unüberschaubarer Markt an Weiterbildungsangeboten für Erzieher/innen - teils herausragender, teils fragwürdiger Qualität. Das Spektrum ist durch eine Vielzahl fachwissenschaftlicher, pädagogischer, methodischer und erwachsenenbildnerischer Ansätze gekennzeichnet und kaum erforscht. Zugangsvoraussetzungen, Abschlüsse, Umfang und Inhalte sind höchst unterschiedlich. Es mangelt an struktureller und inhaltlicher Koordination und so führt das hohe Engagement der Erzieher/innen und Träger kaum zu systematischer Anerkennung der Qualifikationen und zu Aufstiegsmöglichkeiten. Die Nationale Qualitätsinitiative hat wichtige Impulse für die Entwicklung des Systems der Tageseinrichtungen gegeben. Allerdings wurde versäumt, die Qualität der Weiterbildung einzubeziehen. Dabei steht Qualifizierung im Zentrum jeder Qualitätsentwicklung. Darüber gibt es einen fachlichen Konsens, ohne dass hieraus von Politik, Verwaltung und Aus- und Fortbildung Konsequenzen gezogen wurden. In der vorliegenden Studie werden die Qualifikationsanforderungen an Erzieher/innen analysiert und Qualitätskriterien für ein entsprechendes Fort- und Weiterbildungskonzept entwickelt.
    Keywords: ddc:370
    Repository Name: EconStor: OA server of the German National Library of Economics - Leibniz Information Centre for Economics
    Language: German
    Type: doc-type:workingPaper
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  • 9
    Publication Date: 2015-11-04
    Keywords: ddc:300
    Repository Name: EconStor: OA server of the German National Library of Economics - Leibniz Information Centre for Economics
    Language: German
    Type: doc-type:workingPaper
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  • 10
    Publication Date: 2006-10-26
    Description: Three fuel blends conforming to AN-F-58 specifications were tested in order to determine the influence of boiling temperatures and aromatic content on altitude performance in single combustor of 4000-pound-thrust turbojet engine. At simulated engine conditions from an altitude of 30,000 to an altitude of 60,000 feet and 85-percent rated engine speed, the three AN-F-58 fuels showed little difference in performance.
    Type: NACA-RM-E8L20a
    Format: text
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