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221.
Karl Werner 《Ocean Dynamics》1955,8(2):59-65
Zusammenfassung Der Kompensierung von Magnetkompassen geht die Bestimmung der Deviation auf einer hinreichenden Zahl von Kursen voraus. Bei der bisher gebräuchlichen Weise wird mit Hilfe optischer Peilungen die Deviation als Unterschied zwischen dem mi\weisenden Kurs und dem am Kompa\ anliegenden Kurs bestimmt. Bei unsichtigem Wetter ist das Verfahren nicht durchführbar. Auch die Deviationskontrolle auf See an Hand astronomischer Peilungen ist häufig durch schlechte Sichtverhältnisse erschwert oder unmöglich.In der vorliegenden Arbeit werden im Prinzip Kompa\systeme dargestellt, die auf Grund von Messungen der magnetischen Feldstärke am Kompa\ort eine Deviationsbestimmung ermöglichen, ohne da\ optische Peilungen erforderlich sind. Ausgegangen wird dabei von der beim Bidlingmaierschen Doppelkompa\ angewandten Tatsache, da\ der Spreizwinkel, den zwei senkrecht übereinander angeordnete gleichartige Rosensysteme miteinander bilden, ein Ma\ für die Stärke des am Ort vorhandenen magnetischen Feldes ist. Auf Grund des engen Zusammenhanges zwischen magnetischer Feldstärke am Kompa\ort und der Deviation des Kompasses kann aus Messungen der Feldstärke die Deviation bestimmt werden. Wenn mittels üblicher Kompensiermittel die Feldstärke auf allen Kursen gleichgemacht wird, verschwindet die Deviation und der Kompa\ ist kompensiert.Um eine für den Bordgebrauch eines solchen Kompasses bequeme Anzeige der Fehlrichtung zu erhalten, müssen geeignete änderungen des Doppelkompasses vorgenommen werden, die in der Arbeit näher beschrieben sind.
Magnetic compass enabling measurings of the magnetic field intensity for the purpose of adjustment and control of deviation without the necessity of optical bearings
Summary Before magnetic compasses are adjusted, the deviation must be determined for a sufficient number of courses. According to the method applied so far the deviation, i. e. the difference between the magnetic course and the compass course, is determined by means of optical bearings. The method is not practicable in thick weather. The control of deviation at sea by means of astronomical bearings is also frequently difficult or even impossible on account of low visibility.In the present paper, the principles of compass-systems are described which allow to determine deviation on the base of measuring the magnetic field intensity at the compass place without taking optical bearings. Like the double-compass after Bidlingmaier these constructions are based on the fact that the spreading angle which is formed by two equal card systems arranged one vertically above the other is a measure for the intensity of the magnetic field at the compass place. Since there exists a close relation between magnetic field intensity at the compass place and the deviation of the compass, the deviation may be determined by measurings of the magnetic field intensity. When the magnetic field intensity on all courses is equalized by means of ordinary corrector magnets and soft iron correctors, the deviation vanishes, and the compass is adjusted.In order to get a convenient indication of the direction of the magnetic field as necessary for the use of the proposed compass on board ships, suitable modifications must be made to the double-compass. They are described in detail in the present paper.
Notes sur un compas magnétique muni d'un indicateur d'intensité de champ magnétique pour le réglage du compas sans y prendre de relèvements et pour la détermination de déclination
Résumé Le réglage de compas magnétique est précédé de la détermination de déclination effectuée sur un assez grand nombre de routes. Suivant la méthode en usage jusqu'ici, la détermination de déclination se fait à l'aide de relèvements optiques, c.a.d. on détermine la différence entre la route magnétique et la route au compas. Ce procédé, cependant, n'est pas applicable en cas de mauvaise visibilité. La détermination de déclination effectuée en mer à l'aide de relèvements astronomiques est également souvent entravée ou mÊme rendue impossible si la visibilité est mauvaise.Dans le présent travail, on expose, en principe, des systèmes de compas qui permettent de déterminer la déclination sans prendre des relèvements optiques. Pour ce but, on mesure l'intensité de champ magnétique au lieu d'installation de compas. Analogue au double compas d'après Bidlingmaier, on y procède du fait que l'angle formé par les axes de deux égaux systèmes de roses de compas, installés verticalement l'un au dessus de l'autre, permet de déterminer l'intensité de champ magnétique au lieu d'installation de compas. A cause de la relation intime qui existe entre l'intensité de champ magnétique au lieu de compas et la déclination de compas, on peut dériver la déclination de la mesure de l'intensité de champ magnétique. Quand on égalise, à l'aide de moyens usuels de compensation l'intensité de champ magnétique sur toutes les routes, la déclination disparaÎtra et le réglage du compas sera accompli.Afin d'obtenir une indication convenable de la direction du champ magnétique pour l'usage d'un tel compas à bord, il faut apporter de modifications au double compas. Celles-ci sont précisées aux pages suivantes.相似文献
222.
Karl Munkelt 《Ocean Dynamics》1955,8(3):119-127
Zusammenfassung Viele Aufgaben der praktischen Analyse lassen sich bequem und schnell mit Lochkartenmaschinen lösen. Insbesondere führt die Möglichkeit, daß Lochkarten leicht umgeordnet werden können, oft zu erheblichen Rechenvorteilen. Im folgenden wird ein Lochkartenverfahren zur harmonischen Analyse und Synthese entwickelt, das diese Vorzüge der Lochkartenmaschinen erkennen läßt.
On harmonic analysis and synthesis with the aid of punching card machines
Summary Many problems of practical analysis may be easily and rapidly resolved with the aid of punching card machines. Considerable advantages may be derived from the fact that punching cards can be re-arranged without difficulties according to new aspects. On the following pages a punched cards method for the harmonic analysis and synthesis is developed which exhibits the advantage of punching card machines under this special aspect.
Sur l'analyse et la synthèse harmonique à l'aide de machines de comptabilité à cartes perforées
Résumé Beaucoup de problèmes de l'analyse pratique se laissent résoudre d'une manière convenable et rapide au moyen des machines de comptabilité à cartes perforées. En particulier, la possibilité de pouvoir arranger sans inconvénient d'après de nouveaux aspects des cartes perforées souvent offre de considérables avantages. Sur les pages suivantes, un procédé pour l'analyse et la synthèse harmonique est dévelopé qui montre les avantages résultants de l'emploi des machines de comptabilité à cartes perforées.相似文献
223.
The equilibrium conditions of the following reaction 2 zoisite +1 CO2?3 anorthite+1 calcite+1 H2O 2 Ca2Al3[O/OH/SiO4/Si2O7]+1 CO2?3 CaAl2Si2O8+1 CaCO3+1 H2O have been determined experimentally at total pressures of P j= 2000 bars, P f =5000 bars, and P f =7000 bars. Owing to the vertical position of the equilibrium curves in isobaric T- \(X_{{\text{CO}}_{\text{2}} }\) diagrams, the composition of the binary H2O-CO2 fluid phase coexisting with zoisite is independent of temperature in the temperature interval investigated. According to our experiments, orthorhombic zoisite is only stable in equilibrium with a fluid phase at a concentration of CO2 which is less than, respectively, ca. 2 Mol% CO2 at P f =2000 bars, ea. 6 Mol% at P f =5000 bars, and ca. 10 Mol% at P f =7000 bars. Thus, the fluid phase coexisting with zoisite is rich in H2O. While this is independent of temperature the experimental data demonstrate that the influence of pressure cannot be neglected: With increasing pressure the concentration of CO2 of the fluid phase coexisting with zoisite can rise a little. The position of the reaction studied, which is independent of temperature and exhibits small values of \(X_{{\text{CO}}_{\text{2}} }\) ,leads to two important petrogenetic conclusions:
- The occurrence of zoisite is an indicator for a CO2-poor and H2O-rich fluid composition during metamorphism of marly calcsilicates.
- If the concentration of CO2 of the fluid phase coexisting with zoisite exceeds the equilibrium value of \(X_{{\text{CO}}_{\text{2}} }\) calcite+anorthite+H2O is formed from zoisite+CO2. Thus, a considerable increase in the anorthite-content of plagioelase is possible.
224.
The Cretaceous limestones of Chihuahua, Mexico, exhibit both sedimentary-diagenetic and epigenetic-supergene silica deposits which are distinguished from each other on the basis of texture/fabric/structure, composition, colour, presence or absence of certain other minerals such as malachite and/or hematite, structural relationships with the host-rock, and general paragenetic characteristics with each other; all described herein. The criteria offer a useful composite working model during field work. 相似文献
225.
226.
In the Phyllite Group of Crete a stratigraphic succession from Permian to Upper Triassic members is represented. In Carnian parts of this succession in eastern Crete a coherent sheet of Hercynian amphibolites and micaschists is included. It is 20 km long and up to 300 m thick. The Hercynian metamorphics are shown to have been thrusted upon the pre-Carnian part of the Phyllite Group before the Carnian sedimentation continued. A strong, andesitic volcanism was connected with this thrusting in time and space. Tectonic events like these are not known in the outer zones of the Hellenides until now. 相似文献
227.
228.
Flow velocities of active rock glaciers in the Austrian Alps 总被引:1,自引:0,他引:1
High surface flow velocities of up to 3 m a–1 were measured near the front of three active rock glaciers in the western Stubai Alps (Rei‐chenkar) and Ötztal Alps (Kaiserberg and Ölgrube) in Tyrol (Austria) using differential GPS technology. Flow velocities have increased since about 1990. The highest velocities were recorded in 2003 and 2004, but showed a slight decrease in 2005. At the Reichenkar rock glacier, flow rates are constant throughout the year, indicating that meltwater has no significant influence on the flow mechanism. At Ölgrube rock glacier, flow velocities vary seasonally with considerably higher velocities during the melt season. Meltwater is likely to influence the flow of Ölgrube rock glacier as evident by several springs near the base of the steep front. Because the high surface velocities cannot be explained by internal deformation alone on Reichenkar rock glacier, we assume that horizontal deformation must also occur along a well defined shear zone within a water‐saturated, fine‐grained layer at the base of the frozen body. The increased surface flow velocities since about 1990 are probably caused by slightly increased ice temperature and greater amounts of meltwater discharge during the summer, a product of global warming. 相似文献
229.
230.
This paper describes a regional development plan in North East Asia, in the context of regional planning theory and various
geo-political changes which have occurred in the region. Known as the Tumen Regional Development Project, the area encompasses
parts of North Korea, China, and Russia. On the one hand, the geography, the presence of raw material, and social factors
suggest that there may be unique opportunities to develop the region. At the same time, there is increased competition for
capital and resources from other regions in the world. Regionalism, therefore, needs to be seen in a global context. After
critiquing the plan from the perspective of contemporary regional planning theory, a call for a ‘new paradigm’ of development
is issued, one that considers, for example non-traditional industries such as tourism and emphasizes the management of growth
as well as its promotion.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献