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71.
Summary An exact solution of the distribution of the intensity of the telluric field in a halfspace with a spherical inhomogeneity has been obtained by solving the Laplace equation in bipolar coordinates. This exact solution is compared with the presently known approximate solution, obtained by the method of images, and the region of their coincidence has been determined. For the image solution theoretical relations have been derived for computing the anomaly of the magnetic field. Craphs depict many of the properties of the telluric and magnetic fields on the surface of the considered halfspace for various parameters of the given problem.Dedicated to 90th Birthday of Professor Frantiek Fiala 相似文献
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In the production of a special artificial leather (BAREX) in the CSSR wastewaters containing dimethylformamide (DMF) and dimethylamine (DMA) are produced. Investigations have shown that cultures of algae (Scenedesmus quadricauda) are able to use the two substances as a nitrogen nutrient source after a time of adaptation. In the course of the reactions of decomposition the pH-value plays an important part, since at increased values ammonia is released, which has a temporarily inhibitory effect on the production of algae masses and daughter cells. This detrimental effect can be considerably reduced by aeration with carbondioxide containing (3%) air. Since the production of algal biomass is restricted by a phosphorus deficiency, too, a combined treatment with municipal sewage is very advantageous, according to the results from investigations. 相似文献
74.
Four-dimensional modeling of recent vertical movements in the area of the southern california uplift
This paper describes an analytical technique that utilizes scattered geodetic relevelings and tide-gauge records to portray Recent vertical crustal movements that may have been characterized by spasmodic changes in velocity. The technique is based on the fitting of a time-varying algebraic surface of prescribed degree to the geodetic data treated as tilt elements and to tide-gauge readings treated as point movements. Desired variations in time can be selected as any combination of powers of vertical movement velocity and episodic events. The state of the modeled vertical displacement can be shown for any number of dates for visual display. Statistical confidence limits of the modeled displacements, derived from the density of measurements in both space and time, line length, and accuracy of input data, are also provided. The capabilities of the technique are demonstrated on selected data from the region of the southern California uplift. 相似文献
75.
1300 microprobe analyses of glasses, pyroxenes, feldspars, oxides, olivines, troilite and metal in two 0.025 g samples of the Luna 16 return were made in order to characterize the Mare Fecunditatis regolith. 相似文献
76.
The Greenland coastal temperatures have followed the early 20th century global warming trend. Since 1940, however, the Greenland coastal stations data have undergone predominantly a cooling trend. At the summit of the Greenland ice sheet the summer average temperature has decreased at the rate of 2.2 °C per decade since the beginning of the measurements in 1987. This suggests that the Greenland ice sheet and coastal regions are not following the current global warming trend. A considerable and rapid warming over all of coastal Greenland occurred in the 1920s when the average annual surface air temperature rose between 2 and 4 °C in less than ten years (at some stations the increase in winter temperature was as high as 6 °C). This rapid warming, at a time when the change in anthropogenic production of greenhouse gases was well below the current level, suggests a high natural variability in the regional climate. High anticorrelations (r = ?0.84 to?0.93) between the NAO (North Atlantic Oscillation) index and Greenland temperature time series suggest a physical connection between these processes. Therefore, the future changes in the NAO and Northern Annular Mode may be of critical consequence to the future temperature forcing of the Greenland ice sheet melt rates. 相似文献
77.
When height networks are being adjusted, many geodesists advocate the approach where the adjustment should be done by using geopotential numbers rather than the orthometric or normal heights used in practice. This is based on a conviction that neither orthometric nor normal heights can be used for the adjustment because these height systems are not holonomic, meaning–among other things–that height increments (orthometric or normal) when summed around a closed loop do not sum up to zero. If this was the case, then the two height systems could not be used in the adjustment; the non-zero loop closure would violate the basic, usually unspoken, assumption behind the adjustment, namely that the model claiming that height differences are observable is correct. In this paper, we prove in several different ways that orthometric and normal heights are theoretically just as holonomic as the geopotential numbers are, when they are obtained from levelled height differences using actual gravity values. This disposes of the argument that geopotential numbers should be used in the adjustment. Both orthometric and normal heights are equally qualified to be used in the adjustment directly. 相似文献
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Petr Pavlínek 《The Professional geographer》1998,50(1):71-85
This paper evaluates foreign direct investment (FDI) in the Czech Republic and its regional development consequences after the collapse of state socialism. Two types of FDIs are identified: cross border export-oriented investments and market capture investments. The cross border export-oriented investments exploit low cost labor in the service of external markets and are typically concentrated in peripheral areas, mostly along the former West German border. This type of FDI is not likely to contribute to durable regional economies. The market capture investments involve both servicing the Czech market and integrating activities within a larger, multinational corporate network. This type of investment may create more durable sources of regional economic activity. A case study of the Volkswagen/Skoda joint venture is used to examine market capture investments and their consequences for regional development. This paper is based on interviews with plant managers and trade union leaders in companies with foreign investment, governmental officials at the various ministries and state agencies dealing with FDI, and information and data from the secondary sources. 相似文献
80.