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香港大都市规划:前店的规划 总被引:1,自引:0,他引:1
香港和内地在劳动地域分工上被称为“前店后厂”模式。文章回顾了二战以后香港社会经济发展和规划的历史,通过香港大都市规划方案,展望未来,重点研究了分散的空间发展战略规划的原因,并从政治经济的角度进行解释和对比,认为跨界发展的大都市规划是实现香港空间合理化的一种战略。 相似文献
3.
Tongjiang Wang Nelson L. Reginald Joseph M. Davila O. Chris St. Cyr William T. Thompson 《Solar physics》2017,292(8):97
Three-dimensional electron density distributions in the solar corona are reconstructed for 100 Carrington rotations (CR 2054?–?2153) during 2007/03?–?2014/08 using the spherically symmetric method from polarized white-light observations with the inner coronagraph (COR1) onboard the twin Solar Terrestrial Relations Observatory (STEREO). These three-dimensional electron density distributions are validated by comparison with similar density models derived using other methods such as tomography and a magnetohydrodynamics (MHD) model as well as using data from the Solar and Heliospheric Observatory (SOHO)/Large Angle and Spectrometric Coronagraph (LASCO)-C2. Uncertainties in the estimated total mass of the global corona are analyzed based on differences between the density distributions for COR1-A and -B. Long-term variations of coronal activity in terms of the global and hemispheric average electron densities (equivalent to the total coronal mass) reveal a hemispheric asymmetry during the rising phase of Solar Cycle 24, with the northern hemisphere leading the southern hemisphere by a phase shift of 7?–?9 months. Using 14 CR (\(\approx13\)-month) running averages, the amplitudes of the variation in average electron density between Cycle 24 maximum and Cycle 23/24 minimum (called the modulation factors) are found to be in the range of 1.6?–?4.3. These modulation factors are latitudinally dependent, being largest in polar regions and smallest in the equatorial region. These modulation factors also show a hemispheric asymmetry: they are somewhat larger in the southern hemisphere. The wavelet analysis shows that the short-term quasi-periodic oscillations during the rising and maximum phases of Cycle 24 have a dominant period of 7?–?8 months. In addition, it is found that the radial distribution of the mean electron density for streamers at Cycle 24 maximum is only slightly larger (by \(\approx30\%\)) than at cycle minimum. 相似文献
4.
Bridge fragility curves, which express the probability of a bridge reaching a certain damage state for a given ground motion parameter, play an important role in the overall seismic risk assessment of a transportation network. Current analytical methodologies for generating bridge fragility curves do not adequately account for all major contributing bridge components. Studies have shown that for some bridge types, neglecting to account for all of these components can lead to a misrepresentation of the bridges' overall fragilities. In this study, an expanded methodology for the generation of analytical fragility curves for highway bridges is presented. This methodology considers the contribution of the major components of the bridge, such as the columns, bearings and abutments, to its overall bridge system fragility. In particular, this methodology utilizes probability tools to directly estimate the bridge system fragility from the individual component fragilities. This is illustrated using a bridge whose construction and configuration are typical to the Central and Southeastern United States and the results are presented and discussed herein. This study shows that the bridge as a system is more fragile than any one of the individual components. Assuming that the columns represent the entire bridge system can result in errors as large as 50% at higher damage states. This provides support to the assertion that multiple bridge components should be considered in the development of bridge fragility curves. The findings also show that estimation of the bridge fragilities by their first‐order bounds could result in errors of up to 40%. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
5.
Newell Reginald E. Boer George J. Dopplick Thomas G. 《Pure and Applied Geophysics》1973,106(1):1531-1543
Computations of the mean meridional motion field in the stratosphere are applied to ozone distributions to evaluate the associated ozone concentration changes. These changes are compared with those produced by photochemical and quasi-horizontal eddy processes. For the period January–April 1964 there is a cooperative action between the mean and eddy motions with mean subsidence in middle latitudes supplying ozone to be carried polawards and equatorwards by quasi-horizontal eddy processes. At low latitudes mean horizontal motions offset the eddy transport while at high latitudes mean rising motion is the offsetting term. The mean ozone flux through 50 mb, 3.5×1029 molecules sec–1, is comparable with the fluxes evaluated by other techniques.The spring maximum is thought to be due to a modulation of the energy supply to the stratospheric eddies which, in turn, force the mean motions. Longer-term changes are to be expected; for example during Ice Ages when increased tropospheric eddy activity is anticipated there should be higher total ozone. 相似文献
6.
Changes of atmospheric CO2 concentration since 1958 are shown to be related to sea surface temperature changes. The largest contribution to changes arises from the Pacific equatorial upwelling region, with the Indian Ocean and Atlantic contributing only small fractions to the variance. It is hypothesized that the observed relationship is related to the nutrients that are brought up by upwelling cold water, with photosynthesis contributing to a lowering of the partial pressure of CO2 in the sea and thus to a greater tendency for a flux from the air to the sea.Possible longer term variations of sea temperature and CO2 are discussed. 相似文献
7.
Nelson L. Reginald Joseph M. Davila O. C. St. Cyr Douglas M. Rabin Madhulika Guhathakurta Donald M. Hassler Hadi Gashut 《Solar physics》2011,270(1):235-251
An experiment was conducted in conjunction with the total solar eclipse on 29 March 2006 in Libya to measure both the electron
temperature and its flow speed simultaneously at multiple locations in the low solar corona by measuring the visible K-coronal
spectrum. Coronal model spectra incorporating the effects of electron temperature and its flow speed were matched with the
measured K-coronal spectra to interpret the observations. Results show electron temperatures of (1.10±0.05) MK, (0.70±0.08) MK,
and (0.98±0.12) MK, at 1.1 R
⊙ from Sun center in the solar north, east and west, respectively, and (0.93±0.12) MK, at 1.2 R
⊙ from Sun center in the solar west. The corresponding outflow speeds obtained from the spectral fit are (103±92) km s−1, (0+10) km s−1, (0+10) km s−1, and (0+10) km s−1. Since the observations were taken only at 1.1 R
⊙ and 1.2 R
⊙ from Sun center, these speeds, consistent with zero outflow, are in agreement with expectations and provide additional confirmation
that the spectral fitting method is working. The electron temperature at 1.1 R
⊙ from Sun center is larger at the north (polar region) than the east and west (equatorial region). 相似文献
8.
Nathan Gale Reginald G. Golledge William C. Halperin Helen Couclelis 《The Professional geographer》1990,42(3):299-313
Spatial familiarity is a natural language concept that has no well-defined technical interpretation. We explore here some possible dimensions of the concept, provide subjective measurements of the dimensions, and evaluate their independence. The four dimensions examined are locational knowledge, visual recognition, name identification, and interaction frequency. We suggest that both cognitive and behavioral dimensions are embedded in the concept of spatial familiarity and must be part of the meaning of the concept and of any attempt to make it operational. 相似文献
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