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11.
Thermal comfort of man in different urban environments   总被引:2,自引:4,他引:2  
Summary On July 29, 1985, a hot summer day, biometeorological measurements were performed simultaneously in three different urban structures within the city of Munich and in the trunk space of a nearby tall spruce forest. Based on the results of these experiments the following thermophysiologically relevant biometeorological indices were calculated: Predicted mean vote, skin wettedness and physiologically equivalent temperature. These three indices are derived from different models for the human energy balance. They allow the assessment of the thermal components of the microclimates at the selected sites with regard to application in urban planning. The results quantitatively show the great heat stress in the urban structure street canyon, exposed to south, whereas in the trunk space of the tall spruce forest there is nearly an optimal climate even on hot summer days. Between these extremes the results for street canyon, exposed to north show a little higher heat load than for backyard with trees.
Zusammenfassung An einem heißen Sommertag, dem 29. Juli 1985, wurden in drei Stadtstrukturen in München und im Stammraum eines nahegelegenen Fichtenhochwaldes zeitgleich biometeorologische Messungen durchgeführt. Mit den Meßergebnissen wurden folgende thermophysiologisch relevante biometeorologische Indizes berechnet: Predicted mean vote, Hautbenetzungsgrad und physiologisch äquivalente Temperatur. Diese drei Indizes beruhen auf verschiedenen Modellen zur menschlichen Energiebilanz. Mit den drei Indizes wurden die thermischen Komponenten der Mikroklimate an den ausgewählten Meßplätzen im Hinblick auf Stadtplanungsaufgaben bewertet. Die Ergebnisse zeigen quantitativ die relativ große Hitzebelastung bei der Stadtstruktur Straßenschlucht, nach Süd exponiert, während im Stammraum des Fichtenhochwaldes selbst an heißen Sommertagen nahezu optimale Bedingungen herrschen. Zwischen diesen Extremen liegen die Ergebnisse für die anderen Meßplätze, wobei für Straßenschlucht, nach Nord exponiert die Wärmebelastung etwas höher als für Innenhof mit Bäumen ist.


With 6 Figures  相似文献   
12.
Retention of Fe flocs, resulting from the mixing of river water and seawater, was examined in three Maine estuaries. Riverine Fe was found to remain fairly conservative with salinity, implying that the process of floccufation does not necessarily remove Fe from water parcels. Laboratory experiments corroborated the field data by demonstrating that neither gravity nor suspended sediment were very effective in removing flocculated Fe from suspension. However, input of a tannery effluent did appear to result in scavenging of Fe from estuarine waters. Flocculated riverine Fe was found to increase considerably the Fe concentrations of estuarine bottom sediments, with the amount of iron per sediment specific surface area dependent on mean river flow entering an estuary. While no long term retention efficiencies could be calculated for these estuaries, it seems likely that a significant portion of flocculated riverine Fe escapes to shelf waters.  相似文献   
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Zusammenfassung Es wird versucht, die Methoden der statistischen Mechanik auf die statistische Behandlung der kontinuierlichen Mannigfaltigkeit der Erdatmosphäre zu übertragen. Dazu ist es notwendig, daß die hydrodynamischen Bewegungsgleichungen auf eine Hamiltonsche Form gebracht werden. In Analogie zur statistischen Mechanik wird ein Gibbsscher Ansatz einer kanonischen Gesamtheit gemacht, in den die Energiefunktion, die die Atmosphäre als Ganzes beschreibt, eingeht. Mit diesem Ansatz wird die Wahrscheinlichkeit angegeben, daß ein bestimmter Zustand der Atmosphäre, der als Phasenpunkt in einem Phasenraum aufgefaßt wird, in einem Volumelement dieses Phasenraumes anzutreffen ist. Diese Ausgangswahrscheinlichkeit gestattet es, in einem Anwendungsbeispiel eine Verbindung zwischen der mittleren geometrischen Temperaturzustandskurve und der Verteilung der Gesamtmasse der Atmosphäre auf die verschiedenen Dichtewerte herzustellen.
Summary An attempt is made to apply methods of statistical mechanics to the continuous diversity of the terrestrial atmosphere. To this purpose the hydrodynamic equations of motion must be expressed in Hamiltonian form. In analogy to statistical mechanics a Gibbs arrangement of a canonical totality is set up involving the energy-function by which the atmosphere is described as a whole. By this arrangement the probability is given that a certain state of the atmosphere considered as phase point in a phase space exists in a volume-element of this phase space. This initial probability makes it possible to establish, in a practical example, a relation between the average geometrical curve of temperature state and the distribution of the whole mass of the atmosphere over the different density values.

Résumé On tente d'appliquer les méthodes de la mécanique statistique au traitement statistique de la diversité continue de l'atmosphère terrestre. Il est nécessaire pour cela de ramener les équations hydrodynamiques du mouvement aux formes de Hamilton. Par analogie à la mécanique statistique on établit un théorème de Gibbs concernant un ensemble canonique et dans lequel s'insère la fonction d'énergie décrivant l'atmosphère dans son ensemble. Ce théorème fournit la probabilité qu'un état détermié de l'amtosphère considéré comme point de phase dans un espace de phase est rencontré dans un élément de volume de cet espace. Cette probabilité initiale permet, dans un exemple concret, d'établir une relation entre la courbe géométrique moyenne d'état de température et la distribution de la masse totale de l'atmosphère selon les différentes valeurs de la densité.
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14.
The coregistration of complex image pairs is a very important step in synthetic aperture radar interferometry (InSAR) data processing. This letter proposes a novel coregistration method that only needs three arbitrary parts of the two complex images instead of four parts in the existing coregistration methods. This method constitutes an integrated three-part method for InSAR data processing with our contoured-correlation-interferometry method for phase-image generation. Saving one part transmission makes a significant advantage when processing SAR images on satellites. Furthermore, we demonstrate that, by means of using fringe contoured windows instead of squared windows, the accuracy of the coregistration for both the three-part coregistration method and the existing methods can be improved considerably  相似文献   
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Several experiments to measure postimpact burial of seafloor mines by scour and fill have been conducted near the Woods Hole Oceanographic Institution's Martha's Vineyard Coastal Observatory (MVCO, Edgartown, MA). The sedimentary environment at MVCO consists of a series of rippled scour depressions (RSDs), which are large scale bedforms with alternating areas of coarse and fine sand. This allows simultaneous mine burial experiments in both coarse and fine sand under almost identical hydrodynamic forcing conditions. Two preliminary sets of mine scour burial experiments were conducted during winters 2001-2002 in fine sand and 2002-2003 in coarse sand with a single optically instrumented mine in the field of view of a rotary sidescan sonar. From October 2003 to April of 2004, ten instrumented mines were deployed along with several sonar systems to image mine behavior and to characterize bedform and oceanographic processes. In fine sand, the sonar imagery of the mines revealed that large scour pits form around the mines during energetic wave events. Mines fell into their own scour pits, aligned with the dominant wave crests and became level with the ambient seafloor after several energetic wave events. In quiescent periods, after the energetic wave events, the scour pits episodically infilled with mud. After several scour and infilling events, the scour pits were completely filled and a layer of fine sand covered both the mines and the scour pits, leaving no visible evidence of the mines. In the coarse sand, mines were observed to bury until the exposed height above the ripple crests was approximately the same as the large wave orbital ripple height (wavelengths of 50-125 cm and heights of 10-20 cm). A hypothesis for the physical mechanism responsible for this partial burial in the presence of large bedforms is that the mines bury until they present roughly the same hydrodynamic roughness as the orbital-scale bedforms present in coarse sand.  相似文献   
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