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421.
Ella Ödmann 《Geoforum》1973,4(1):31-41
Urbanisation is a functional change in land utilisation which requires a high degree of coordination in time and space. Swedish society has not considered it possible to entrust this coordination to the free market forces. A number of measures was introduced during the latter part of the sixties with a view to coordinating housing development by means of local authority-land ownership and preventing land speculation. In a recently published report of a Government Commission it is proposed that dwellings receiving Government housing loans (more than 90 % of building construction) shall only be built on land which is owned by the local authorities. The local authorities may then be assumed to be the only purchasers of land for housing development purposes. Their housing policy can be given a more short-term character and can be better adapted to urban planning. Urban development in Sweden during recent decades is characterised by a struggle between the two groups of our mixed-economy society, i. e., a social democratic government, and capitalistic enterprise. As far as the private individual is concerned, both parties are remote decision makers. The important question is whether an improvement in town environment may be expected before the private individual has been given a chance to influence planning. The relationship between housing development and land ownership in some Swedish towns over the period 1950–1970 is presented as an example of the realization of land policy. 相似文献
422.
Dr. Hansgeorg FÖrster Dipl.-Min. Annemarie Schmitz-Wiechowski 《International Journal of Earth Sciences》1970,59(2):637-648
Zusammenfassung Die Verfasser entwickeln aus den Ergebnissen ihrer feldgeologischen und petrographischen Untersuchungen — gestützt auf gesteinsmechanische Überlegungen und tektonische Experimente — ein neues geologisches Konzept für das Tauernwestende.
FrauSchmitz-Wiechowski (Wiechowski 1968) hat die Phyllitserie östlich des Brenner untersucht und tektonische Grenzflächen verfolgt.Förster bearbeitete hauptsächlich das Gebiet westlich des Brenner. 相似文献
A new concept about the geology of the Brenner region is developed from field observations, petrographic investigations, mechanic considerations and tectonic experiments.
Résumé Les auteurs présentent une conception géologique nouvelle de la partie occidentale des Tauern d'après leurs observations géologiques sur le terrain et leurs recherches pétrographiques, en s'appuyant sur des considérations de la mécanique des roches et des expériences tectoniques.
- .
FrauSchmitz-Wiechowski (Wiechowski 1968) hat die Phyllitserie östlich des Brenner untersucht und tektonische Grenzflächen verfolgt.Förster bearbeitete hauptsächlich das Gebiet westlich des Brenner. 相似文献
423.
424.
RUDOLF O. WEBER PETER TALKNER INGEBORG AUER REINHARD BÖHM MARJANA GAJIĆ-ČAPKA KSENIJA ZANINOVIĆ RUDOLF BRÁZDIL PAVEL FAŠKO 《Climatic change》1997,36(3-4):327-344
Daily maximum and minimum temperatures from 29 low-lying and mountain stations of 7 countries in Central Europe were analyzed. The analysis of the annual variation of diurnal temperature range helps to distinguish unique climatic characteristics of high and low altitude stations. A comparison of the time series of extreme daily temperatures as well as mean temperature shows a good agreement between the low-lying stations and the mountain stations. Many of the pronounced warm and cold periods are present in all time series and are therefore representative for the whole region. A linear trend analysis of the station data for the period 1901–1990 (19 stations) and 1951–1990 (all 29 stations) shows spatial patterns of similar changes in maximum and minimum daily temperatures and diurnal temperature range. Mountain stations show only small changes of the diurnal temperature range over the 1901–1990 period, whereas the low-lying stations in the western part of the Alps show a significant decrease of diurnal temperature range, caused by strong increase of the minimum temperature. For the shorter period 1951–1990, the diurnal temperature range decreases at the western low-lying stations, mainly in spring, whereas it remains roughly constant at the mountain stations. The decrease of diurnal temperature range is stronger in the western part than in the eastern part of the Alps. 相似文献
425.
BRAJŠA R. RUŽDJAK V. VRŠNAK B. POHJOLAINEN S. URPO S. SCHROLL A. WÖHL H. 《Solar physics》1997,171(1):1-34
The solar rotation rate obtained using the microwave Low-brightness-Temperature Regions (LTRs) as tracers in the heliographic range ± 55° from the years 1979–1980, 1981–1982, 1987–1988, and 1989–1991 varied from 3% to 4% in medium latitudes, and below 1% at the equator. Using H filaments as tracers at higher latitudes from the years 1979, 1980, 1982, 1984, and 1987, the solar rotation rate variation was between 2% and 8%. This represents an upper limit on the rotation rate variation during the solar activity cycle. Such changes could be caused by short-lived, large-scale velocity patterns on the solar surface. The Sun revealed a higher rotation rate on the average during the maxima of the solar activity cycles 21 and 22, i.e., in the periods 1979–1980 and 1989–1991, respectively, which differs from the rotation rates (lower on the average) in some years, 1981–1982 and 1987–1988, between the activity maximum and minimum (LTR data). Simultaneous comparison of rotation rates from LTRs and H filament tracings was possible in very limited time intervals and latitude bands only, and no systematic relationship was found, although the rotation rates determined by LTRs were mostly smaller than the rotation rates determined by H filaments. The errors obtained by applying different fitting procedures of the LTR data were analyzed, as well as the influence of the height correction. Finally, the north–south asymmetry in the rotation rate investigated by LTRs indicates that the southern solar hemisphere rotated slower in the periods under consideration, the difference being about 1%. The reliability of all obtained results is discussed and a comparison with other related studies was performed. 相似文献
426.
Ali Osman Öncel Ian Main Ömer Alptekin Patience Cowie 《Pure and Applied Geophysics》1996,147(1):147-159
We investigate the nature of temporal variations in the statistical properties of seismicity associated with the North Anatolian Fault Zone between longitudes 31°–41°E during the instrumental period 1900–1992. Temporal variations in the seismicb value and the fractal (correlation) dimensionD
c
of earthquake epicenters are examined for earthquakes of magnitudeM
S
4.5, using sliding windows of 100 consecutive events.b varies temporally between 0.6 and 1.0, andD
c
between 0.6 and 1.4, both representing significant fluctuations above the errors in measurement technique. A strong negative correlation (r=–0.85) is observed betweenb andD
c
, consistent with previous observation of seismicity in Japan and southern California. Major events early in this century (M
S
7) are associated with lowb and highD
c
, respectively consistent with greater stress intensity and greater spatial clustering of epicenters—both implying a greater degree of stress concentration at this time. 相似文献
427.
A deliberate tracer experiment has been carried out in an enclosed lagoon in a coastal area. The tracer used was a perfluorocarbon, perfluoro-
-methyldecalin (PMD), analysed using liquid-liquid extraction and electron capture gas chromatography. The results show good recovery of the tracer, indicating that adsorption and volatilization did not occur to an appreciable extent over the short time period of the experiment. A mathematical model, PHOENICS, developed for simulation of flow systems, was used to simulate the experiment. 相似文献
428.
—A moderately strong earthquake (M w = 6.2) occurred in the town of Dinar at 17.57 UT on October 1, 1995, taking the lives of 90 people and damaging about 4500 buildings. Its epicenter is located near the Dinar-Çivril fault and its focal mechanism is linked to a northeast-southwesterly tensional stress field arising from the interaction between the subducting African plate and the overriding Aegean-Anatolian plate in the eastern Mediterranean.¶Surface cracks of the October 1 earthquake have been observed 10 km continuously along the Dinar-Çivril fault. The cracks have displayed a mode of dip-slip; however, some have also indicated lateral slip. The different modes of slip are generally in agreement with the fault plane solution and are indicators of the complex nature of the rupture process.¶In investigating the earthquake hazard of the Dinar-Çivril fault and proximity, the maximum likelihood method was used to estimate seismic hazard parameters of b-value, seismicity activity rate λ m and the expected maximum magnitude M max?. The data consisted of the historical data covering the period between 1800–1900 and instrumental data between 1900 and 1992. This method, allowing use of the mixed earthquake catalogue containing both historical and instrumental earthquake data, yielded values of 0.70, 1.92 and 7.14 for b, λ m and M max?, respectively. The recurrence time estimated for an earthquake of a magnitude of M w = 6.2 is 123 years. The non-occurrence probabilities of such an earthquake in 1 and 50 years are 0.21 and 0.04, respectively. 相似文献
429.
430.
An identification of anomalies 31–34 is presented for the North Atlantic. North of the Azores-Gibraltar Ridge this implies a revision of the identification of the magnetic anomalies older than anomaly 26. DSDP site 10 in the western North Atlantic appears to be located on the old end of anomaly 33. The relative spacings of anomalies 29–34 in the North and South Atlantic, North and South Pacific and Indian Oceans are compared and the estimated relative widths of the magnetic polarity intervals in the Late Cretaceous are revised. 相似文献