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221.
A method of landscape evaluation based on the anthropo-ecological approach is worked out. The procedure consists of three stages, viz., general, special and optimization. Within the general stage, the structural arrangement of the landscape is evaluated by means of the concept of geo-ecological sites (GES), which are distributed into four zones (A, B, C, D) according to the degrees of their anthropic disturbance. The zoning performed makes it possible to select those geo-ecological sites where eco-critical relationships can be expected to appear; in order to eliminate such situations, transition zones are calculated for the geo-ecological sites concerned. The outcome of this approach is a proposal of a new structural arrangement of the geo-ecological sites, solving eco-critical situations and serving as a basis for the special and optimization stages of the anthropo-ecological method. 相似文献
222.
J. Kozák T. Lokajíček J. Šílený Reviewer V. Rudajev 《Studia Geophysica et Geodaetica》1989,33(4):322-337
Summary The results of laboratory measurements on square perspex models with a stress concentrator under uniaxial compression are presented. An attempt was made to interpret these results in order to determine the mutual relations between the mechanical parameters characterizing the treated models, including their focal zones, parameters of model loading, parameters of seismogenic displacement and parameters of radiated elastic pulses. Particular attention was given to the study of slip displacement, slip velocity, rupture velocity, nucleation points of rupture propagation, nucleation points of elastic radiation and to the frequency analysis of radiated pulses. Measurements of the displacement in the focal zone enabled us to determine the source function, to construct theoretical seismograms in a far field and to compare them with the real pulses from ultrasonic transducers located there. This allowed testing theoretical and experimental approaches to the study of how slip displacement, slip velocity and rupture velocity are related to the parameters of radiated pulses. 相似文献
223.
Summary We find no effect of the interplanetary magnetic field(IMF) sector boundary crossing in ozone at altitudes ranging from the middle stratosphere(10 hPa) to the lower mesosphere(0.4 hPa) at middle latitudes(40°–60° N), based on winter data over the period of December 1979–December 1982.
Резюме Мы не нaшлu нuкaко о эффекma nересеченuя секmорноŭ рaнuцы межnлaнеmно о мa нumно о nоля в озоне в облaсmu высоm меж?rt;у сре?rt;неŭ сmрamосфероŭ(10 Пa) u нuжнеŭ мезосфероŭ(0,4 Пa) нa сре?rt;нuх шuроmaх(40°–60° с.ш.), nрuменяя зuмнuе ?rt;aнные зa nерuо?rt; ?rt;екaбрь 1979 – ?rt;екaбрь 1982 .相似文献
224.
Summary Sets of virtual poles corresponding to sets of geomagnetic field values at equidistant points, lying along circles of latitude, were defined on the basis of the 1980 IGRF extending to degree and order 8. Certain places on the Earth's surface yield virtual poles lying very close together. The segments of the virtual pole paths, corresponding to these places, have a large curvature. The mentioned places of the Earth's surface are supposed to be areas with a low rate of the westward drift. They form continuous zones that show a certain relation to global-tectonics features.
uum ¶rt; 8- n¶rt;a ¶rt;a¶rt; aaumu n 1980 u u nmu uma n, mmmu nm uu n ma, a u¶rt;umam ¶rt; naa m ma nmu nua¶rt;am uma n, m uu ¶rt; ¶rt;. amu u, mmmu mu ma, um uu. ¶rt;naam, m nm ma nmu m amu, m m ana¶rt; ¶rt;a ua. u am n na, m naam a m uua mmuu.相似文献
225.
Jan Peczkis 《Climatic change》1988,12(2):199-208
Conclusions An extinction optical depth of 20 is necessary for total darkness (NAS, 1985), although a considerably lower value than that can produce near-total darkness because scattered light does not generate shadows and contrast. It can be seen that the Dresden firestorm smoke cloud, calculated under the conditions usually assumed in nuclear winter calculations, should have resulted in total darkness over a vast area.Using the 500 mb chart, it can be retrodicted that the smoke plume, as part of the counterclockwise circulation about the low over southern Sweden, was over central Poland as dawn broke on the 14th. Indeed, at 9 AM (Table I), smoke from what had been Dresden should have been passing over what had been Warsaw. Depending upon the specific size of the plume at the time, anywhere from a few hundred thousand to over ten million people should have been plunged into darkness.It appears unlikely that such extensive darkening could have gone unreported (especially in the light of the heightened awareness resulting from wartime conditions, and the proximity of the Soviet/German front). This has direct implications for the aforementioned initial uncertainties in nuclear winter. Possible explanations include: (a) Very low smoke emission factors - perhaps even lower than 0.001 (Broyles, 1985); (b) Substantial removal of smoke in the black rain that followed the firestorm (Irving, 1963, p. 175). Values for prompt smoke removal reaching 90% are not out of the realm of possibility (Schneider et al., 1986; Penner, 1986).The present author is of the opinion that more effort should be expended by students of the nuclear winter phenomenon to learn from WWII mass urban fires. Many eyewitnesses to these events must still be living, and there must be at least some scientifically-useable material in archives. For example, there is a 122-m, 10-min motion film of the Dresden firestorm (Irving, 1963, p. 159). It is in the film archives of the Imperial War Museum. Perhaps some new details of firestorm genesis, spread, etc. could be learned from it. There must be other log books, such as the one of Kraus (1986), which could well yield scientificallyvaluable information. 相似文献
226.
Plastic particles were found to be common pollutants in stomachs of Wilson's Storm Petrels and Cape Petrels breeding on the Antarctic continent. Highest incidence of plastics was found in chicks of Wilson's Storm Petrels that had died before fledging. Few or no plastics were found in Snow Petrels and Antarctic Petrels. Evidence suggests that most plastics originate from wintering areas outside the Antarctic, and that relatively few plastics are available in Antarctic waters. Possible hazards of plastic levels observed in Wilson's Storm Petrels are discussed. 相似文献
227.
Summary Procedure for verifying the agreement between parameters common to the basic and connecting trigonometric net. Procedure of determining the accuracy of the connecting net. This determination concerns not only the relativized accuracy of the points of the connecting network, but also the mutual accuracy of the points of the basic net relative to the points of the connecting net and the global accuracy of the resultant net. The procedure takes into account the accuracy of the points of the basic net which remain unchanged in computing the coordinates of new points.
m¶rt; ¶rt; nu au u naam¶rt;mu u nu¶rt;u m. m¶rt; ¶rt; u mmu nu¶rt;u mu. a aam m mum nua mmu m nu¶rt; mu, ma au mmu m mu n mu ma nu¶rt;u mu ua mmu mu mu. m¶rt; umam mm m mu, m aa uu ¶rt;uam m mam uu.相似文献
228.
Thomas Foken Jan Pretel Reviewer J. Bednář Reviewer Z. Jaňour 《Studia Geophysica et Geodaetica》1988,32(3):318-328
In the present paper the first results of the international KOPEX-86 experiment are presented. The experiment took place at the Kopisty Atmospheric Observatory of the Institute of Physics of the Atmosphere in Prague as part of a special project of the Commission of the Academy of Sciences in Planetary Geophysics (KAPG) in June and July 1986. Using 4 ultrasonic anemometers at 4 levels up to 80 m, Doppler-SODAR and wind-, temperature- and radiation balance gradients from 2 to 80 m, a complex investigation of the atmospheric boundary layer in an industrial area was made. The authors present the first results of
am n mam ¶rt;a¶rt; numa -86. num n¶rt;u mu u u u 1986. a num mu amuu mumma uuu am aa nma . u nu 4 amuu am a 4 ma ¶rt; 80 , ¶rt;nn ¶rt;aa u uua¶rt;um mu ma, mnam u a¶rt;uauu 2 ¶rt; 80 n¶rt;uu n u¶rt;au nau am. m n¶rt;aam n mam, aau
相似文献
| the anthropogenic influence on the energy exchange in the atmospheric boundary layer. |
| the influence of a complex terrain on the turbulent characteristics and their vertical distribution. |
| u¶rt;au amn ¶rt;mu a muu na am, |
| uu n mmu a aamumuu mmmu u a u mua an¶rt;u. |
229.
Summary The tidal deformations of a viscoelastic body are studied using the simple Kelvin-Voigt model. Expressions for the phase lag and amplitude change of the displacement vector are derived. The energy dissipation rate is calculated for the main disturbing bodies and for diurnal and semidiurnal tidal waves.
am nuu ¶rt;auu n ma ua-ma. ¶rt; au ¶rt; ana¶rt;au a u uu anum¶rt; ma u. aumaa m ¶rt;uunauu uu ¶rt; u a a m u nm .相似文献
230.
Zdeněk Šimon Jan Kostelecký Antonín Zeman Reviewer L. Skalský 《Studia Geophysica et Geodaetica》1988,32(1):16-23
Summary It is recommended that the data from measurements with supraconducting gravity meters be also analysed with regard to verifying the gravitation absorption hypothesis. Based on theoretical data from a3-year period, the spectrum of the assumed effect of shielding the gravitational influence of the Sun by the Earth's body on the value of the acceleration of gravity has been calculated for the tidal station Brussels (Figs 2a–e).
¶rt;aam aauuam ¶rt;a uu n¶rt;uaumau ma mu u nuunm n¶rt;auaumauu. a mmuu ¶rt;a a mmu nu¶rt; u nm n¶rt;naa ma auauaumau ¶rt;mu a m a uu u u mmu ¶rt; nuu mauu (u. 2a–).相似文献