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221.
This paper describes a regional development plan in North East Asia, in the context of regional planning theory and various
geo-political changes which have occurred in the region. Known as the Tumen Regional Development Project, the area encompasses
parts of North Korea, China, and Russia. On the one hand, the geography, the presence of raw material, and social factors
suggest that there may be unique opportunities to develop the region. At the same time, there is increased competition for
capital and resources from other regions in the world. Regionalism, therefore, needs to be seen in a global context. After
critiquing the plan from the perspective of contemporary regional planning theory, a call for a ‘new paradigm’ of development
is issued, one that considers, for example non-traditional industries such as tourism and emphasizes the management of growth
as well as its promotion.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
222.
Karl Raitz 《Geographical review》1998,88(3):363-387
ABSTRACT. Federal support for planning and building roads provided an opportunity to create a new kind of place, the American roadside. The roadside grew up beside the public road as a distinct private space, yet the two were linked as road travelers came to depend on the services provided by people who lived at the road's edge. Federal road-improvement legislation brought discipline to the surveying, construction, and configuration of roads. But roadside structures remained largely the creation of local people, who built a vernacular landscape that was undisciplined and in strong contrast to the road's regimentation. The roadside became a new kind of space occupying the unstable zone between the discipline of the road and the informality of the countryside, a spatial contradiction that gave license to a new, free-wheeling, mercantile logic, an improvisational departure from the staid formality of Main Street. 相似文献
223.
Thomas R. Karl 《Climatic change》1988,12(2):179-197
The issue of whether the secular climate (twentieth century) is stationary or changing to some new semi-permanent state is clouded by the presence of so-called climate fluctuations. The twentieth century climate record of the United States reveals a substantial number of decadal fluctuations which occur in all seasons for both temperature and precipitation. Recent examples of such behavior include changes in winter and summer temperature variability and increases in transition season precipitation. Statistical evidence suggests that a substantial portion of these fluctuations, even those which are remarkably unusual, are merely manifestations of a stochastic process which possesses weak year-to-year persistence as viewed from an a posteriori perspective. The implications of this result are particularly important with respect to the formulation of physical causes of the fluctuations. The results emphasize the desirability of well-founded clearly-stated a priori theories of climate change as well as the limited usefulness of widely used climate normals. 相似文献
224.
Precipitation collected in continuously open containers for about a year at seven sites around the United States was analyzed for10Be,90Sr,210Pb and238U. Based on these data and long-term precipitation,90Sr and210Pb delivery patterns, the stratospheric, tropospheric and recycled10Be components in the collections were estimated and the global10Be production rate was assessed. Single station production rate estimates range from 0.52 × 106 atoms cm−2 yr−1 to 2.64 × 106 atoms cm−2 yr−1. The mean value is 1.21 × 106 atoms cm−2 yr−1 with a standard error of 0.26 × 106 atoms cm−2 yr−1. 相似文献
225.
After World War II Saudi Arabia has experienced spectacular changes. Based on huge oil and gas revenues a particularly rapid
growth of population and a spectacular urbanization took place. One of the most booming cities in the desert environment of
the arabian peninsula is the Kingdoms capital city of Riyadh. With a built-up area of 3.5 km2 only before 1950 the city's present-day expansion reaches more than 500 km2. During the same period of time the population of Riyadh grew from less than 50,000 in 1945 to more than 1.4 Mio. in 1985.
Such an explosive development can be documented best by a satellite image. In this paper the process of urbanization of Riyadh
is presented by the interpretation of a MOMS image taken in 1984, documenting the geographic situation, urban structures,
and the city's development. 相似文献
226.
Karl E. SEIFERT 《Geostandards and Geoanalytical Research》1984,8(1):35-38
Silicate rock standards AN-G, BHVO-1, QLO-1, RGM-1, SDC-1 and STM-1 have been analyzed for 7 REE (La, Ce, Sm, Eu, Tb, Yb and Lu), Na2 O, FeOt , Sc, Co, Cr, Ta, Hf and Th by instrumental neutron activation analysis. The mean values are compared to those from other studies reported in the literature. 相似文献
227.
Difunctional organic nitrates are important products of the atmospheric reaction of NO3 radicals with unsaturated hydrocarbons about which relatively little is known. In a continuation of the investigation of the atmospheric chemistry of such compounds, the UV absorption spectra of the following organic dinitrates and keto nitrates have been quantitively measured in the gas phase at 298±2 K and atmospheric pressure: 1,2-propandiol dinitrate, CH3CH(ONO2)CH2(ONO2); 1,2-butandiol dinitrate, CH3CH2CH(ONO2)CH2(ONO2); 2,3-butandiol dinitrate, CH3CH(ONO2)CH(ONO2)CH3;cis 1,4-dinitrooxy-2-butene, CH2(ONO2)CH=CHCH2(ONO2); 3,4-dinitrooxy-1-butene, CH2(ONO2CH(ONO2)CH=CH2; -nitrooxy acetone, CH3COCH2(ONO2); 1-nitrooxy-2-butanone, CH3CH2COCH2(ONO2); 3-nitrooxy-2-butanone, CH3CH(ONO2)COCH3.Although the UV spectra of the nitrates are all very similar in shape those of the keto nitrates are red-shifted compared to the dinitrates and in the spectral range of atmospheric interest (>290 nm) their absorption cross-sections are approximately a factor of 5 higher. The cross-sections of the dinitrates are a factor of 2 higher than those reported in the literature for the corresponding alkyl mononitrates.The UV absorption cross-sections of the difunctional nitrates were used in combination with solar actinic flux data to estimate photolysis frequencies and consequently atmospheric lifetimes for these compounds. The results indicate that for the saturated difunctional nitrates studied in this work photolysis will generally be somewhat some important than reaction with OH radicals as an atmospheric removal process. However, for unsaturated nitrates loss due to reaction with OH will dominate over photolysis as an atmospheric sink.Preliminary FT-IR analyses of the photolysis products of -nitrooxy acetone, 3-nitrooxy-2-butanone and 2,3-butandiol dinitrate using both mercury and fluorescent lamps indicate that NO2 is released in the primary step. The further reactions of the radicals thus produced result in the formation of CO, aldehydes and PAN. The possible significance of the results for difunctional organic nitrate as reservoirs for reactive odd nitrogen NO
y
in the atmosphere, especially during the night, is briefly discussed. 相似文献
228.
Ten meter firn cores were collected during the Swedish Antarctic Expedition to Dronning Maud Land, in 1988/89. The oxygen isotope stratigraphy in the cores was used to obtain a proxy-temperature record and a surface accumulation record for the last 15–30 years. The 18O record from cores on the ice shelf and the escarpment area, below 2000 m a.s.l., show high variability and little year-to-year correspondence to each other or with the temperature record from nearby Halley. A stacked firn core record was produced to avoid local variability and minor dating errors; this record shows more similarities to the Halley temperature record. The 18O records from high altitude cores show a much better correspondence to the Halley temperature record over the last 30 years, implying that the source of precipitation is more stable compared to the coastal area. The welldeveloped 18O stratigraphy in the cores from coastal Dronning Maud Land makes it promising for future work using ice cores as paleoclimatic records. 相似文献
229.
E. Karl Sauer 《Engineering Geology》1977,11(1):1-21
Sauer, E. Karl, 1977. A valley crossing in Pleistocene deposits. Eng. Geol., 11:1–21.Proglacial meltwater channels are of considerable importance in geotechnical engineering in Southern Saskatchewan. Dams, roads, bridges and urban development are major projects involving these channels. The Arm River crossing illustrates the types of problems that can occur in highways constructed across these channels, including instability, groundwater control and excavation through a boulder pavement. This discussion demonstrates how these problems can be resolved by establishing the geology of the sites and designing to preclude geotechnical problems. The investigation involved rotary drilling, geophysical logging, installation of piezometers and engineering analysis. 相似文献
230.
Based on GIS and statistical methods, with the help of searching historical literatures andcalculating the landscape indices, the land use changes of Qian'an County in both spatial and temporalaspects from 1945 to 1996 has been analyzed in this paper. And the driving forces of land use changesand their ecological effects are discussed too. The main findings of this study are as follows:(1)Landuse changed greatly in Qian'an during 1945-1996, characterized by a decrease in grassland, wetlandand water bodies,and an increase in cultivated land, saline-alkali land, and the land for housing andother construction purposes. Grassland decreased by 175,828.66 ha, and cultivated land increased by 相似文献