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1.
, , 38 B=2.1±1.1 G l
o=99°±24°,b=0° N
e=0.03±0.01 –3 Z- (h400 ). , 100–150 . 相似文献
2.
К. А. Пирагас В. И. Жданов А. Н. Александров И Л. Е. Пирагас 《Astrophysics and Space Science》1978,57(2):283-302
- , . . , . - . 相似文献
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. , , . , ( ) . ( =2) ( ) . 相似文献
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, , , . , (z103) - , - , , , 1 (z10). , . 相似文献
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А. T. Barabanov 《Geography and Natural Resources》2016,37(2):106-113
An analysis is made of the chief causes for degradation of agricultural lands: exhaustive agricultural land use, poor planning quality of land use management, deforestation, low volumes of forest planting and reforestation, and a high degree of plowing of lands. The principles of adaptive-landscape generation and land use practices are substantiated on the basis of a system approach to the exploitation of the natural-resource potential and a package of anti-degradation measures. The structure flowchart is given for the model of adaptive-landscape generation as developed on the basis of assessing the natural-climatic conditions, land resources, the degree of land degradation, and analyzing the set of indicators and criteria for a classification of landscapes. It is found that the key elements of the adaptive-landscape organization of land use on slopes are a typization of lands, the determination of the land use pattern, and the employment of technologies, methods and measures to ensure a normal functioning of agroecosystems. The following groups of lands are identified: gentle near-watershed slopes with a steepness of up to 2–3°; near-network lands, the lower boundary of which runs along the edge of the hydrographic network, and lands on the hydrographic network. The schematic of the organization of a large balka catchment is provided. 相似文献
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1 ПостановказадачиНадежныйпрогнозвременивозникновенияземлетрясенияможетбытьобеспеченлишькомплексомпрогностическихпараметров. Прогностическаяценностькаждогопараметранеодинакова,какиразличенмеханизмформированияаномальныхэффектоввразличныхполях.Этосоздает… 相似文献
8.
1 ВведениеВсвязистем,чтоРеспубликаУзбекистанрасположенанасейсмоактивнойтерриторииЗападногоТянь- Шанябольшуюважностьимеютвопросысейсмическогорайонированияипрогнозированияместа,силыивременисильныхземлетрясений. СэтойцельювИнститутесейсмологииАНТУзБылпрове… 相似文献
9.
在中国,自从1957年起,与各种地球物理方法(解决石油地貭任务)广泛发展的同时,比較年輕的大地电流法也得到了很大的发展。大地中存在大地电流,这在一百多年前就知道了。以往的观測表明,大地电流具有脉动性貭,它的大小和方向随时間而变化,并在地球表面很多地区同时出現。大地电流的产生、它的变化以及与地磁場的关系,还沒有搞得相当清楚,这是一个需要进一步研究的問題。 相似文献
10.
А. Л. Куницын 《Celestial Mechanics and Dynamical Astronomy》1971,3(2):222-226
. . . , , m
1, m2, m3, n ( .
The conditions of stability of the constant libration solutions of the general three-bodies problem obtained by E. Routh through investigation of the linearized perturbed motion equations are analised. To the values of the masses of the three bodies which satisfy boundary conditions of the region of stability the locus of all corresponding centers of masses is laid down in accordance with. It occurs that this locus is a circle, its centre coinciding with the geometric centre of the trianglem 1, m2, m3 and its radius being a function of exponent in the law of attraction of the bodies. The motion may be stable only if the centre of masses of the bodies lies outside the circle mentioned above. In the case of the Newtonian law of attraction the radius of this circle equals 0,943 |rmax| where |rmax| is a distance of the vertex from the centre of the trianglem 1, m2, m3. Thus stability is possible (if it is generally possible) inside a very small region in this case.相似文献