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991.
Effectiveness of animation in trend visualization 总被引:1,自引:0,他引:1
Robertson G Fernandez R Fisher D Lee B Stasko J 《IEEE transactions on visualization and computer graphics》2008,14(6):1325-1332
Animation has been used to show trends in multi-dimensional data. This technique has recently gained new prominence for presentations, most notably with Gapminder Trendalyzer. In Trendalyzer, animation together with interesting data and an engaging presenter helps the audience understand the results of an analysis of the data. It is less clear whether trend animation is effective for analysis. This paper proposes two alternative trend visualizations that use static depictions of trends: one which shows traces of all trends overlaid simultaneously in one display and a second that uses a small multiples display to show the trend traces side-by-side. The paper evaluates the three visualizations for both analysis and presentation. Results indicate that trend animation can be challenging to use even for presentations; while it is the fastest technique for presentation and participants find it enjoyable and exciting, it does lead to many participant errors. Animation is the least effective form for analysis; both static depictions of trends are significantly faster than animation, and the small multiples display is more accurate. 相似文献
992.
The accurate determination of the optimized structures of large molecules is, computationally quite expensive. As an alternate to the conventional approaches to structural optimization, we have explored the accuracy and speed-up obtained when variants of the fragmentation optimization and recombination method (FORM) are used. Specifically, the method was applied to eight prototypical molecules -n-decane, hexa-alanine, a long conjugate hydrocarbon molecule, a large polar conjugated molecule, large (5,5) armchair single-walled carbon nanotubes, a salen-aluminum complex and a multiply H-bonded system (two conformers of vancomycin aglycon with Di-N-acetyl-l-Lys-d-Ala-d-Ala - without optimizing the structure of the whole molecules. We find that FORM can predict the structure of these molecules with an acceptable accuracy, all at a computational cost that is 2-11 times less than conventional quantum mechanical methods at the Hartree-Fock (HF), density functional theory (DFT) and MP2 level of accuracy. FORM may therefore represent a viable approach for the fast structural predictions of large molecules. 相似文献
993.
Datatype-generic programs are programs that are parameterised by a datatype. We review the allegorical foundations of a methodology of designing datatype-generic programs. The notion of F-reductivity, where F parametrises a datatype, is reviewed and a number of its properties are presented. The properties are used to give concise, effective proofs of termination of a number of datatype-generic programming schemas. The paper concludes with a concise proof of the well-foundedness of a datatype-generic occurs-in relation. 相似文献
994.
Dr. Jörg Dehnert Dipl.-Geogr. Peggy Eifert Dipl.-Geoök. Antje Feldmann Dr. René Schenk Dipl.-Geogr. Roland Dimmer Dipl.-Hydrol. Karin Kuhn 《Grundwasser》2005,10(1):14-24
Kurzfassung
Die Wasserrahmenrichtlinie regelt den Schutz von Grund- und Oberflächengewässern und fordert eine nachhaltige Wassernutzung. Sie legt einen Zeitplan fest, um bis zum Jahr 2015 für alle Gewässer einen guten Zustand zu erreichen. Der erste Schritt ist eine Bestandsaufnahme der Gewässer. Für das Grundwasser besteht diese aus einer erstmaligen Beschreibung, einer weitergehenden Beschreibung und der Prüfung der Auswirkungen menschlicher Tätigkeit auf das Grundwasser. Die Wasserrahmenrichtlinie wird unabhängig von administrativen Grenzen innerhalb von hydrologischen Einzugsgebieten umgesetzt. Im deutschen Teil des Flusseinzugsgebietes der Elbe wurden 5 Koordinierungsräume gegründet. Der Koordinierungsraum Mulde-Elbe-Schwarze Elster (MES) wird vorgestellt. Beispielhaft für die angewandten Methoden wird die Beurteilung diffuser Stoffeinträge in das Grundwasser bei der erstmaligen Beschreibung erläutert. Die Ergebnisse der Bestandsaufnahme Grundwasser im Koordinierungsraum MES werden präsentiert. Von 54 Grundwasserkörpern ist für 25 Körper aufgrund der Belastungen durch Punktquellen und diffuse Quellen, wegen des mengenmäßigen Zustands oder sonstiger anthropogener Einwirkungen die Zielerreichung nach der Wasserrahmenrichtlinie unklar/unwahrscheinlich.
Status review groundwater for the Water Framework Directive in the coordination zone Mulde-Elbe-Schwarze Elster
Abstract The Water Framework Directive (WFD) governs the protection of groundwater and surface water and promotes sustainable water use. It sets up a timetable to ensure that a good status of all waters will be achieved by 2015. The first step is a status review of the waters. For groundwater, this procedure is divided into an initial characterisation, a further characterisation and a review of the impacts of human activity on groundwater. The WFD is to be implemented independently of administrative boundaries within hydrological river basins. In the German part of the Elbe river basin district five coordination zones have been established. The Mulde-Elbe-Schwarze Elster (MES) coordination zone is introduced. As an example for the applied methods, the assessment of the pressures of groundwater by diffuse sources (initial characterisation) will be explained. Then the outcome of the status review groundwater in the coordination zone MES will be presented: From the 54 individual bodies of groundwater 25 bodies will probably not achieve the environmental objectives of the WFD because of the pressures point sources, diffuse sources, quantitative status or other anthropogenic impacts.相似文献
995.
996.
Experimental investigations were performed to examine the effects of flame interactions with different multiple obstacles within chambers of different L/D ratios. The basic chamber consists of a rectangular box, 200 mm in height, with a 700 mm x 700 mm cross-section and a large top-venting area of 700 mm x 210 mm. The chambers were designed at 200 mm height intervals, and the maximum height of the chambers was 1000 mm. Five chambers were employed to examine the flame interaction with multiple bars in each chamber. Three different multiple obstacles were used: square, triangular and circular cross-sections with blockage ratios of 30% and 43%. The results of flame speed and pressures of different L/D ratios were discussed. The flame speeds and pressures associated with the obstacles showed little significant difference in chambers with the L/D ratios of 0.29 and 0.57. However, chambers over a ratio of 0.86 became sensitive to the obstacle types, the L/D ratio and the blockage ratios. The highest overpressures were observed with the triangular obstacles while the lowest overpressures occurred with the cylindrical obstacles. The flame development was correlated with pressure development in the chambers having L/D ratios of 0.86-1.43. 相似文献
997.
Heckmann D Meyer A Laufer B Zahn G Stragies R Kessler H 《Chembiochem : a European journal of chemical biology》2008,9(9):1397-1407
The inhibition of integrin function is a major challenge in medicinal chemistry. Potent ligands are currently in different stages of clinical trials for the antiangiogenic therapy of cancer and age-related macula degeneration (AMD). The subtype alpha5beta1 has recently been drawn into the focus of research because of its genuine role in angiogenesis. In our previous work we could demonstrate that the lack of structural information about the receptor could be overcome by a homology model based on the X-ray structure of the alphavbeta3 integrin subtype and the sequence similarities between both receptors. In this work, we describe the rational design and synthesis of high affinity alpha5beta1 binders, and the optimisation of selectivity against alphavbeta3 by means of extensive SAR studies and docking experiments. A first series of compounds based on the tyrosine scaffold resulted in affinities in the low and even subnanomolar range and selectivities of 400-fold against alphavbeta3. The insights about the structure-activity relationship gained from tyrosine-based ligands could be successfully transferred to ligands that bear an aza-glycine scaffold to yield alpha5beta1 ligands with affinities of approximately 1 nm and selectivities that exceed 10(4)-fold. The ligands have already been successfully employed as selective alpha5beta1 ligands in biological research and might serve as lead structures for antiangiogenic cancer therapy. 相似文献
998.
Ashino M Obergfell D Haluska M Yang S Khlobystov AN Roth S Wiesendanger R 《Nature nanotechnology》2008,3(6):337-341
The hollow core inside a carbon nanotube can be used to confine single molecules and it is now possible to image the movement of such molecules inside nanotubes. To date, however, it has not been possible to control this motion, nor to detect the forces moving the molecules, despite experimental and theoretical evidence suggesting that almost friction-free motion might be possible inside the nanotubes. Here, we report on precise measurements of the mechanical responses of individual metallofullerene molecules (Dy@C82) confined inside single-walled carbon nanotubes to the atom at the tip of an atomic force microscope operated in dynamic mode. Using three-dimensional force mapping with atomic resolution, we addressed the molecules from the exterior of the nanotube and measured their elastic and inelastic behaviour by simultaneously detecting the attractive forces and energy losses with three-dimensional, atomic-scale resolution. 相似文献
999.
Shorubalko I Leturcq R Pfund A Tyndall D Krischek R Schön S Ensslin K 《Nano letters》2008,8(2):382-385
A highly sensitive charge detector is realized for a quantum dot in an InAs nanowire. We have developed a self-aligned etching process to fabricate in a single step a quantum point contact in a two-dimensional electron gas and a quantum dot in an InAs nanowire. The quantum dot is strongly coupled to the underlying point contact that is used as a charge detector. The addition of one electron to the quantum dot leads to a change of the conductance of the charge detector by typically 20%. The charge sensitivity of the detector is used to measure Coulomb diamonds as well as charging events outside the dot. Charge stability diagrams measured by transport through the quantum dot and charge detection merge perfectly. 相似文献
1000.