Spatial and temporal variability of Antarctic krill: implications for stock assessment     

McClatchie  Sam; Greene  Charles H.; Macaulay  Michael C.; Sturley  Darrell R.M. 《ICES Journal of Marine Science》1994,51(1):11-18

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External ownership and control: the impact of industrial organization on the regional economy     

James O. Wheeler  Sam Ock Park 《Geoforum》1984,15(2):243-252

This study seeks to determine the role of external ownership and control of branch manufacturing plants in a traditionally peripheral region of the United States, the states of Georgia and South Carolina. The data are derived from a questionnaire survey sent to branch plants in the two states. The analysis is based on whether the branch plants are locally, regionally, nationally or internationally headquartered. The study identified the degree to which headquarter location affects the spatial pattern of material inputs, market location, and communication flows and personnel movements. The authority for making various decisions is also analyzed for branch plants based on the location of the headquarters.  相似文献   

The Montenegro,Yugoslavia, earthquake of April 15, 1979: source orientation and strength     

David M. Boore  John D. Sims  Hiroo Kanamori  Sam Harding 《Physics of the Earth and Planetary Interiors》1981,27(2):133-142

Long-period teleseismic P, S and Rayleigh waves and geologic considerations indicate that the Montenegro earthquake involved thrust faulting on a plane striking nearly parallel to the Adriatic coast and dipping ca. 15° toward the Yugoslav mainland. There is some support from modeling of body waves recorded on long-period WWSSN instruments for a focal depth of 22 km, but the possibility of a multiple source and the difficulty of matching some of the detailed characteristics of the P- and S-wave forms reduce our confidence in the determination of the depth. Fortunately, the source orientation and moment of the event are not sensitive functions of the depth. The long-period (256 s) moment was 4.6 × 10¹⁹ Nm (4.6 × 10²⁶ dyne-cm). The moment obtained by fitting the first cycle of P and S waves recorded on WWSSN long-period instruments is about four times smaller. This increase of moment with period is consistent with spectral estimates of the moment from SH waves recorded at SRO and ASRO stations.  相似文献   

Regional adjustment of inertial gravity disturbance vector measurements by optimal two-dimensional smoothing     

Dr. Sam C. Bose  Dr. James R. Huddle 《Journal of Geodesy》1981,55(4):340-353

A two-dimensional signal processing algorithm is developed to obtain smoothed estimates of the gravity disturbance vector from vector measurements obtained by an inertial surveying system. The method differs from a conventional least squares regional adjustment of such measurements in that it accommodates a signal model in the smoothing process. Using principles from the physical theory of geodesy, it is shown that for a local region on the surface of the earth, an appropriate signal model is obtained by applying the two-dimensional Laplacian operator to a function representing the surface disturbance potential and equating the result to spatial white noise. The model of the vector measurement is the three orthogonal spatial derivatives of a three dimensional disturbance potential evaluated at the surface contaminated by additive white noise. The problem of simultaneous smoothing of all the gravity disturbance measurements from all survey traverses in the region is solved by representing the surface disturbance potential by a two-dimensional Karhunen-Loeve expansion that makes no specific reference to either the geometry or the ordering of the parameter space, thereby making no assumptions of causality, stationarity or isotropy. The problem of estimating the gravity anomaly and the two vertical deflection components reduces to estimating the Karhunen-Loeve coefficients which are uncorrelated and rapidly converging. Simulation results as well as smoothing of actual gravity disturbance vector measurements obtained by the U.S. Army Engineer Topographic Laboratories (USAETL) with the Rapid Geodetic Survey System (RGSS) at the White Sands Missile Range (WSMR) are presented in the paper. An analysis of these results shows that the optimal two-dimensional smoother obtains a performance benefit relative to conventional regional least squares by a factor of 2 and a benefit relative to single-traverse smoothed results by a factor of 4.

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Sommaire Un algorithme de traitement du signal en deux dimensions est développé pour obtenir une estimation lissée du vecteur de la perturbation de la pesanteur à partir des mesures de vecteur obtenues avec un système d’arpentage inertiel. La méthode diffère d’un compensation régionale conventionnelle par moindres carrés de telles mesures, par le fait qu’elle contient un modèle du signal dans le processus de compensation. En s’appuyant sur les principes de la géodésie physique, il est montré que pour une région locale de la surface de la terre, un modèle approprié du signal est obtenu en appliquant l’opérateur à deux dimensions de Laplace à une fonction représentant le champ perturbateur à la surface de la terre et égalisant le résultat à un bruit blanc spatial. Le modèle du vecteur de mesures est défini par les trois dérivées spatiales de la fonction tridimensionnelle du potentiel perturbateur évaluées à la surface et contaminées par un bruit blanc. Le problème du lissage de toutes les mesures de gravité perturbatrice obtenues à partir des polygonales effectuées est résolu en représentant le potentiel perturbateur à la surface à l’aide d’un développement Karhunen-Loeve à deux dimensions qui ne fait aucunement référence à la géométrie ou à l’ordre des paramètres; ceci prévient toute dépendance spatiale des points adjacents. Le problème de l’estimation de l’anomalie de la gravité et des deux composantes de la déviation de la verticale se réduit à celle des coefficients Karhunen-Loeve qui sont non-corrélés et convergent rapidement. Les résultats de simulation aussi bien que le lissage des données du vecteur de perturbation de la pesanteur foumi par l’U.S. Army Engineer Topographics Labs (USAETL) sont présentés. L’analyse de ces résultats montre que le lissage optimal à deux dimensions améliore les résultats par un facteur 2 comparés aux résultats d’une compensation régionale par moindres carrés, et par un facteur 4 comparés aux résultats lissés d’une simple traverse.

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Presented at the Second International Symposium on Inertial Technology for Surveying and Geodesy, Banff, Canada, June 1–5, 1981.  相似文献   

The simulation of diurnal surface thermal contrast in sea ice and tundra terrain     

Dr. Sam I. Outcalt 《Theoretical and Applied Climatology》1973,21(2-3):147-156

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Analysis of seismically triggered slides off Israel     

Sam Frydman  Mark Talesnick 《Environmental Geology》1988,11(1):21-26

Evidence of large submarine slides, presumably seismically triggered, is evident on the Israeli continental slope. This article presents a study of the earthquake characteristics which were likely to have caused these slides. Four seismic records with different characteristics were used as input, and propagation and response analyses were carried out. The results of these analyses suggest that the slides were caused by one or more large magnitude events resulting in low frequency tremors propagating through the slope profile. It is likely that these earthquakes were located on the Jordan Rift.  相似文献   

The Influence of American geography on Korean geography     

Sam Ock Park 《GeoJournal》2004,59(1):69-72

Korean modern geography emerged from the dark age of unfortunate Japanese colonial rule after liberation in 1945, and has grown rapidly since the 1960s. Modern geographical theories and methodologies were introduced to Korea by the Korean geographers who received PhD degrees in the United States and returned home to teach at universities in Korea, especially in the 1970s and early 1980s. American geography has influenced the progress of the modern geography in Korea in various ways — education systems, curricula for college students, training graduate students — and research methodologies in Korean geography during the last half-century have been directly and indirectly influenced by American geography. The influence has had, however, both positive and negative effects in the development of Korean geography. There is a tendency in recent years to reinterpret Western theories and concepts in the Korean context, considering distinctive regional and cultural characteristics.  相似文献   

Field observations of soil temperature and water tension feedback effects on needle ice nights     

Dr. Sam I. Outcalt 《Meteorology and Atmospheric Physics》1971,20(1):43-53

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The simulation and implications of thermal plumes produced by Arctic construction in smooth terrain     

Dr. Sam I. Outcalt 《Theoretical and Applied Climatology》1972,20(3-4):261-267

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Diffusion of sea water ions—I. Diffusion of sea water into a dilute solution     

S Ben-Yaakov 《Geochimica et cosmochimica acta》1972

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