排序方式： 共有11条查询结果，搜索用时 62 毫秒
1.
Hansjörg Weinmann 《Aquatic Sciences - Research Across Boundaries》1967,29(2):427-449
Zusammenfassung Es werden drei Verfahren n?her untersucht, welche zur Bemessung von Regenwasserkanalisationen den sogenannten Kanalspeicherraum
zu berücksichtigen versuchen. Die Verfahren vonMüller-Neuhaus undGruhler k?nnen wegen Unzul?nglichkeiten in den Annahmen neben den bew?hrten Fliesszeit-und Summen-linienverfahren nicht bestehen.
Das italienische Verfahren eignet sich wegen der schwierigen Berechnung des Wasserinhaltes im Kanalnetz nicht zur praktischen
Dimensionierung. Da zudem die Voraussetzungen aller ?Speicherverfahren? mit den festgelegten überschreitungsintervallen der
Regenintensit?ten unvertr?glich sind, ist ihre Anwendung nicht gerechtfertigt.
Summary Three methods for the dimensioning of storm water sewers have been investigated which emphasize the storage volume of the sewers. Due to inadequate assumptions, the methods proposed byMüller-Neuhaus andGruhler proved to be inapplicable and cannot replace the hitherto used rational method and ‘Summenlinienverfahren’. The Italian method based on the difficult evaluation of the water volume within the sewerage system is too complicated for practical use. Furthermore, all calculation methods considering the storage capacity are based on assumptions which are incompatible with the chosen design value of the recurrence interval of the rainfall intensities. Their application is not recommended.相似文献
2.
It is well known that high-leverage observations significantly affect the estimation of parameters. In geodetic literature,
mainly redundancy numbers are used for the detection of single high-leverage observations or of single redundant observations. In this paper a further objective method for the detection of groups of important and less important (and thus redundant) observations is developed. In addition, the parameters which are predominantly
affected by these groups of observations are identified. This method thus complements other diagnostics tools, such as, e.g.,
multiple row diagnostics methods as described in statistical literature (see, e.g., Belsley et al. in Regression diagnostics:
identifying influential data and sources of collinearity. Wiley, New York, 1980). The method proposed in this paper is based
on geometric aspects of adjustment theory and uses the singular value decomposition of the design matrix of an adjustment
problem together with cluster analysis methods for regression diagnostics. It can be applied to any geodetic adjustment problem
and can be used for the detection of (groups of) observations that significantly affect the estimated parameters or that are
of negligible impact. One of the advantages of the proposed method is the improvement of the reliability of observation plans
and thus the reduction of the impact of individual observations (and outliers) on the estimated parameters. This is of particular importance for the very long baseline interferometry
technique which serves as an application example of the regression diagnostics tool. 相似文献
3.
FIRST RESULTS FROM VIRGO,THE EXPERIMENT FOR HELIOSEISMOLOGY AND SOLAR IRRADIANCE MONITORING ON SOHO 总被引：1，自引：0，他引：1
Fröhlich Claus Andersen Bo N. Appourchaux Thierry Berthomieu Gabrielle Crommelynck Dominique A. Domingo Vicente Fichot Alain Finsterle Wolfgang Gómez Maria F. Gough Douglas Jiménez Antonio Leifsen Torben Lombaerts Marc Pap Judit M. Provost Janine Roca Cortés Teodoro Romero José Roth Hansjörg Sekii Takashi Telljohann Udo Toutain Thierry Wehrli Christoph 《Solar physics》1997,170(1):1-25
First results from the VIRGO experiment (Variability of solar IRradiance and Gravity Oscillations) on the ESA/NASA Mission SOHO (Solar and Heliospheric Observatory) are reported. The observations started mid-January 1996 for the radiometers and sunphotometers and near the end of March for the luminosity oscillation imager. The performance of all the instruments is very good, and the time series of the first 4–6 months are evaluated in terms of solar irradiance variability, solar background noise characteristics and p-mode oscillations. The solar irradiance is modulated by the passage of active regions across the disk, but not all of the modulation is straightforwardly explained in terms of sunspot flux blocking and facular enhancement. Helioseismic inversions of the observed p-mode frequencies are more-or-less in agreement with the latest standard solar models. The comparison of VIRGO results with earlier ones shows evidence that magnetic activity plays a significant role in the dynamics of the oscillations beyond its modulation of the resonant frequencies. Moreover, by comparing the amplitudes of different components ofp -mode multiplets, each of which are influenced differently by spatial inhomogeneity, we have found that activity enhances excitation. 相似文献
4.
Hansjörg Weinmann 《Aquatic Sciences - Research Across Boundaries》1967,29(1):284-301
Summary The design principles of Venturi flumes in sewage plants are explained and a simple method for the calculation of the throat
section is given.
相似文献
5.
Thierry Appourchaux Raymond Burston Yanbei Chen Michael Cruise Hansjörg Dittus Bernard Foulon Patrick Gill Laurent Gizon Hugh Klein Sergei Klioner Sergei Kopeikin Hans Krüger Claus Lämmerzahl Alberto Lobo Xinlian Luo Helen Margolis Wei-Tou Ni Antonio Pulido Patón Qiuhe Peng Achim Peters Ernst Rasel Albrecht Rüdiger Étienne Samain Hanns Selig Diana Shaul Timothy Sumner Stephan Theil Pierre Touboul Slava Turyshev Haitao Wang Li Wang Linqing Wen Andreas Wicht Ji Wu Xiaomin Zhang Cheng Zhao 《Experimental Astronomy》2009,23(2):491-527
ASTROD I is a planned interplanetary space mission with multiple goals. The primary aims are: to test general relativity with
an improvement in sensitivity of over three orders of magnitude, improving our understanding of gravity and aiding the development
of a new quantum gravity theory; to measure key solar system parameters with increased accuracy, advancing solar physics and
our knowledge of the solar system; and to measure the time rate of change of the gravitational constant with an order of magnitude
improvement and the anomalous Pioneer acceleration, thereby probing dark matter and dark energy gravitationally. It is an
international project, with major contributions from Europe and China and is envisaged as the first in a series of ASTROD
missions. ASTROD I will consist of one spacecraft carrying a telescope, four lasers, two event timers and a clock. Two-way,
two-wavelength laser pulse ranging will be used between the spacecraft in a solar orbit and deep space laser stations on Earth,
to achieve the ASTROD I goals. A second mission, ASTROD (ASTROD II) is envisaged as a three-spacecraft mission which would
test General Relativity to 1 ppb, enable detection of solar g-modes, measure the solar Lense–Thirring effect to 10 ppm, and
probe gravitational waves at frequencies below the LISA bandwidth. In the third phase (ASTROD III or Super-ASTROD), larger
orbits could be implemented to map the outer solar system and to probe primordial gravitational-waves at frequencies below
the ASTROD II bandwidth.
相似文献
| Wei-Tou NiEmail: |
6.
7.
Claus Braxmaier Hansj?rg Dittus Bernard Foulon Ertan G?klü Catia Grimani Jian Guo Sven Herrmann Claus L?mmerzahl Wei-Tou Ni Achim Peters Benny Rievers étienne Samain Hanns Selig Diana Shaul Drazen Svehla Pierre Touboul Gang Wang An-Ming Wu Alexander F. Zakharov 《Experimental Astronomy》2012,34(2):181-201
ASTROD I is a planned interplanetary space mission with multiple goals. The primary aims are: to test General Relativity with an improvement in sensitivity of over 3 orders of magnitude, improving our understanding of gravity and aiding the development of a new quantum gravity theory; to measure key solar system parameters with increased accuracy, advancing solar physics and our knowledge of the solar system; and to measure the time rate of change of the gravitational constant with an order of magnitude improvement and the anomalous Pioneer acceleration, thereby probing dark matter and dark energy gravitationally. It is envisaged as the first in a series of ASTROD missions. ASTROD I will consist of one spacecraft carrying a telescope, four lasers, two event timers and a clock. Two-way, two-wavelength laser pulse ranging will be used between the spacecraft in a solar orbit and deep space laser stations on Earth, to achieve the ASTROD I goals.For this mission, accurate pulse timing with an ultra-stable clock, and a drag-free spacecraft with reliable inertial sensor are required. T2L2 has demonstrated the required accurate pulse timing; rubidium clock on board Galileo has mostly demonstrated the required clock stability; the accelerometer on board GOCE has paved the way for achieving the reliable inertial sensor; the demonstration of LISA Pathfinder will provide an excellent platform for the implementation of the ASTROD I drag-free spacecraft. These European activities comprise the pillars for building up the mission and make the technologies needed ready. A second mission, ASTROD or ASTROD-GW (depending on the results of ASTROD I), is envisaged as a three-spacecraft mission which, in the case of ASTROD, would test General Relativity to one part per billion, enable detection of solar g-modes, measure the solar Lense-Thirring effect to 10 parts per million, and probe gravitational waves at frequencies below the LISA bandwidth, or in the case of ASTROD-GW, would be dedicated to probe gravitational waves at frequencies below the LISA bandwidth to 100?nHz and to detect solar g-mode oscillations. In the third phase (Super-ASTROD), larger orbits could be implemented to map the outer solar system and to probe primordial gravitational-waves at frequencies below the ASTROD bandwidth. This paper on ASTROD I is based on our 2010 proposal submitted for the ESA call for class-M mission proposals, and is a sequel and an update to our previous paper (Appouchaux et al., Exp Astron 23:491?C527, 2009; designated as Paper I) which was based on our last proposal submitted for the 2007 ESA call. In this paper, we present our orbit selection with one Venus swing-by together with orbit simulation. In Paper I, our orbit choice is with two Venus swing-bys. The present choice takes shorter time (about 250?days) to reach the opposite side of the Sun. We also present a preliminary design of the optical bench, and elaborate on the solar physics goals with the radiation monitor payload. We discuss telescope size, trade-offs of drag-free sensitivities, thermal issues and present an outlook. 相似文献
8.
Hansjörg Schmassmann 《Aquatic Sciences - Research Across Boundaries》1956,18(1):144-155
Ohne Zusammenfassung 相似文献
9.
Dr. Ulrich von Rad Walter Sigl Hansjörg Oeltzschner 《International Journal of Earth Sciences》1970,60(1):145-164
During 64 days (in June, July, and August 1967–1969), bottom currents have been measured by self-recordingRichardson current meters in the central Gulf of Manfredonia (Southern Adriatic Sea, Italy). The currents show mean velocities of 2–4 cm/sec and maximum velocities ranging from 10–14 cm/sec at 35–50 cm above the sea floor, and maximum velocities of 22 cm/sec at 250 cm above the sediment surface (see Table 1, Fig. 4). During the four measuring periods, NW- to NE-directed current vectors prevailed (Fig. 3): they can be explained by the assumption of a clockwise (anticyclonic) captive eddy or vortex in the Gulf, moving opposite to the constant, “summer-outgoing” Adriatic Gradient Current (Zore-Armanda 1968), which flows to the SE along the Italian coast (Fig. 1). The current directions are opposite to the prevailing wind directions, blowing during the summer mostly from the NW, N and NE; this might be explained by the activity of a northward compensation undercurrent, induced by those winds and possibly also by southeast-flowing surface (gradient) currents. The clockwise 360° rotation of current directions (velocity: 2–13 cm/sec) during one day (June 24/25, 1968) is explained by the influence of a spring tide with a tidal range of 35 cm (Fig. 6). These bottom currents, measured in summer, are only capable of redepositing the river-supplied, clay- to silt-size sediment material by suspension transport. During winter storms with wave action reaching down to a depth of 10 m (?) and swell from strong SE-winds with a longer fetch, it is supposed that current velocities are 3–5 times higher than in summer and sufficient to transport also fine sand. The characteristic distribution of total heavy minerals and of euhedral pyroxenes (Fig. 7 a, b) within the Gulf of Manfredonia indicates that the sediment supplied by the Apennine rivers (mainly River Ofanto) is being re-distributed to the NW and N by longshore drift and by nearshore currents belonging to a clockwise eddy system. This explanation could be verified by the direct current measurements. 相似文献
10.
Helen Bennion Gavin L. Simpson N. John Anderson Gina Clarke Xuhui Dong Anders Hob?k Piero Guilizzoni Aldo Marchetto Carl D. Sayer Hansj?rg Thies Monica Tolotti 《Journal of Paleolimnology》2011,45(4):415-431
This paper aims to determine the ecological and chemical reference conditions (~1800?C1850 AD) and degree of floristic change at nine enriched lakes, covering a range of types across Europe, using fossil diatom assemblages in dated sediment cores and application of total phosphorus (TP) transfer functions. Additionally the study assesses the potential of analogue matching as a technique for identifying reference sites and for estimating reference TP concentrations for the study lakes using a training set of 347 European lakes and 719 diatom taxa. Oligotrophic, acidophilous to circumneutral taxa were predominant in the reference samples of several of the deep lakes, and benthic Fragilaria spp. dominated the reference samples of two high alkalinity shallow lakes. The degree of floristic change from the reference sample, assessed using the squared chord distance (SCD) dissimilarity coefficient, revealed that two sites had experienced slight change (Lago Maggiore, Felbrigg Lake), five experienced moderate change (Mjoesa, Loch Davan, Loch Leven, White Lough, Esthwaite Water), and two showed evidence of major change (Groby Pool, Piburger See). For three lakes, there were no analogues in the diatom dataset owing to the uniqueness and diversity of the diatom reference assemblages. For the remaining six sites the number of analogues ranged from 2 to 44. For two deep lakes most of the analogues seemed appropriate as they were of the same type and had low TP concentrations. However, for two other deep lakes and two shallow lakes some of the analogues differed markedly in their depth and alkalinity from the lake in question or had TP concentrations seemingly too high to represent reference conditions suggesting that the analogues may not be suitable as reference sites. For the deep lakes, similar reference TP values were calculated using the EDDI Combined TP transfer function and the analogue matching technique with concentrations typically <20 ??g L?1. However, for the shallow lakes, the analogue matching method produced inferred values considerably higher than those of the transfer function. The wide ecological tolerances of many of the diatom taxa found in the reference samples most likely explain the selection of inappropriate analogue sites. In summary, the study demonstrates that palaeoecological techniques can play a valuable role in determining reference conditions and indicates that the analogue matching technique has the potential to be a useful tool for identifying appropriate reference sites for lakes impacted by eutrophication. 相似文献