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91.
Industrial relocation of Hong Kong manufacturing firms: towards an expanding industrial space beyond the Pearl river delta 总被引:2,自引:0,他引:2
This paper explores the recent industrial relocation of Hong Kong manufacturing firms in the Pearl River Delta. Based on a
combination of recent surveys, four in-depth case studies and nearly 20 firm interviews through the end of 2008, the paper
argues that in response to a dynamic business environment in the region, some Hong Kong manufacturing firms in the PRD are
forced to design new spatial strategies. The paper also identifies the different relocation strategies adopted by Hong Kong
manufacturing firms, namely, total relocation, stratified relocation and “pseudo relocation”. The industrial space of Hong
Kong manufacturing firms will be expanded beyond the PRD. In addition, the new round of relocation of Hong Kong manufacturers
is a response to the initiative ushered in by the provincial and local governments in order to achieve the objectives of industrial
upgrading, sustainable environment and regional balanced development. 相似文献
92.
93.
94.
Wave‐equation based methods, such as the estimation of primaries by sparse inversion, have been successful in the mitigation of the adverse effects of surface‐related multiples on seismic imaging and migration‐velocity analysis. However, the reliance of these methods on multidimensional convolutions with fully sampled data exposes the ‘curse of dimensionality’, which leads to disproportional growth in computational and storage demands when moving to realistic 3D field data. To remove this fundamental impediment, we propose a dimensionality‐reduction technique where the ‘data matrix’ is approximated adaptively by a randomized low‐rank factorization. Compared to conventional methods, which need for each iteration passage through all data possibly requiring on‐the‐fly interpolation, our randomized approach has the advantage that the total number of passes is reduced to only one to three. In addition, the low‐rank matrix factorization leads to considerable reductions in storage and computational costs of the matrix multiplies required by the sparse inversion. Application of the proposed method to two‐dimensional synthetic and real data shows that significant performance improvements in speed and memory use are achievable at a low computational up‐front cost required by the low‐rank factorization. 相似文献
95.
The characteristics of latitudinal angles of solar wind flow (θv) observed near earth have been studied during the period 1973-2003. The average magnitude of θv shows distinct enhancements during the declining and maximum phases of the sunspot cycles. A close association of Bz component of IMF in the GSE system and the orientation of meridional flows in the solar wind is found which depends on the IMF sector polarity. This effect has been studied in typical geomagnetic storm periods. The occurrence of non-radial flows is also found to exhibit heliolatitudinal dependence during the years 1975 and 1985 as a characteristic feature of non-radial solar wind expansion from polar coronal holes. 相似文献
96.
Robert H. Hammerschlag Felix C. M. Bettonvil Aswin P. L. Jägers Guus Sliepen 《Earth, Moon, and Planets》2009,104(1-4):83-86
Vacuum solar telescopes solve the problem of image deterioration inside the telescope due to refractive index fluctuations of the air heated by the solar light. However, such telescopes have a practical diameter limit somewhat over 1 m. The Dutch Open Telescope (DOT) was the pioneering demonstrator of the open-telescope technology without need of vacuum, now pursued in the German GREGOR. Important ingredients for this technology are primary beam completely open to natural wind flow, stiff but still open design by principal stiff overall geometries in combination with carefully designed joints and completely open-foldable dome constructions based on tensioned strong cloth. Further developments to large sizes are made within the framework of the design study for a European Solar Telescope (EST). 相似文献
97.
Rainfall variability and kinetic energy in Southern Nigeria 总被引:1,自引:1,他引:0
Felix K. Salako 《Climatic change》2008,86(1-2):151-164
A decreasing trend of rainfall has been observed in West Africa, where rainfall erosivity is also considered to be high. Therefore,
this study was carried out to evaluate the variability of rainfall and its erosivity in two contrasting zones in southern
Nigeria between 1977 and 1999 to understand the implications of climate variability on rainfall erosivity. The study sites
were Ibadan, a sub-humid zone, and Port-Harcourt, a humid zone. Time of occurrence of rainfall, rainfall amount (A), intensity (I
15 and I
30), kinetic energy (E) and rainfall erosivity factor (R), were evaluated. Kinetic energy was estimated with Brown–Foster (BF) equation, making the rainfall erosivity (product of
kinetic energy and intensity) to be designated as EI
30-BF and EI
15-BF. The frequency of rainfall during daylight (06:00–18:00 h) was 48% for Ibadan and 69% for Port-Harcourt. There were time-specific
differences in daily rainfall occurrence between the zones, suggesting a strong influence of local effects on rainfall generation,
such as, relief in Ibadan and proximity to the sea in Port-Harcourt. Annual E was 213 MJ ha−1for Ibadan and 361 MJ ha−1 for Port-Harcourt. Ibadan had a significantly higher daily E than Port-Harcourt because of higher intensity while Port-Harcourt had significantly higher annual E than Ibadan because of higher annual rainfall amount. Annual erosivity at Ibadan using the EI
30-BF was 9,742 MJ mm ha−1 h−1 whereas it was 15,752 MJ mm ha−1 h−1 at Port-Harcourt. Using the EI
15-BF, Ibadan had an annual value of 14,806 MJ mm ha−1 h−1 while Port-Harcourt had 20,583 MJ mm ha−1 h−1. Thus, annual rainfall erosivity was significantly higher in the humid than the sub-humid zone because of higher amount of
rainfall but the reverse was the case with daily erosivity because of higher intensities in the sub-humid zone. Rainfall intensity
was, therefore, a key measure of erosivity. There was a strong positive relationship between rainfall erosivity and rainfall
amount. Between 1977 and 1988, 50–88% of the 12 years had rainfall erosivity which exceeded the long-term average but rainfall
erosivity was less than the long-term average between 1989 and 1999. This suggested a decreasing trend in erosivity due to
the decreasing trend in rainfall amount in West Africa. However, the trend did not imply lesser soil erosion and environmental
degradation risks. 相似文献
98.
We use pairs of parallel mounted laser profile scanners to measure main debris-flow variables in two debris-flow channels in central and southern Switzerland. The scanners measure the instantaneous cross-sectional geometry of debris flows at rates of 25–100 Hz, and we apply large-scale particle image velocimetery to estimate velocity. The scanners also provide direct measurements of flow depth. From these data, we were able to estimate debris-flow depth, velocity and discharge for 16 out of 17 events. These results are consistent with discharge estimated from a system of geophones and a radar gauge for two available datasets. We also investigated debris-flow geometry to quantify rheology-controlled cross-flow convexity and found that four events manifest strong surface convexity at their surge fronts where we expect the largest boulders and low pore-fluid pressures. The scanners provide a completely new view of debris-flow dynamics and channel morphology and present novel opportunities to measure discharge and investigate debris-flow geometries. 相似文献
99.
The mountainous areas of Central Asia provide substantial water resources, and studying change in water storage and the impacts of precipitation and snow cover in the mountain ranges of Central Asia is of the greatest importance for understanding regional water shortages and the main factors. Data from the GRACE(Gravity Recovery and Climate Experiment) satellites, precipitation products and snow-covered area data were used to analyze the spatio-temporal characteristics of water storage changes and the effects of precipitation and snow cover from April 2002 to December 2013. The results were computed for each mountain ranges, and the following conclusions were drawn. The water storage in the mountainous areas of Central Asia as a whole increases in summer and winter, whereas it decreases in autumn. The water storage is affected by precipitation to some extent and some areas exhibit hysteresis. The area of positive water storage changes moves from west to east over the course of the year. The water storage declined during the period 2002–2004. It then returned to a higher level in 2005–2006 and featured lower levels in 2007–2009 Subsequently, the water storage increased gradually from 2010 to 2013. The Eastern Tianshan Mountains and Western Tianshan Mountain subzones examined in this study display similar tendencies, and the trends observed in the Karakorum Mountains and the Kunlun Mountains are also similar. However, the Eastern Tianshan Mountains and Western Tianshan Mountains were influenced by precipitation to a greater degree than the latter two ranges. The water storage in Qilian Mountains showed a pronounced increasing trend, and this range is the most strongly affected by precipitation. Based on an analysis of all investigated subzones, precipitation has the greatest influence on total water storage relative to the snow covered area in some areas of Central Asia. The results obtained from this study will be of value for scientists studying the mechanisms that influence changes in water storage in Central Asia. 相似文献
100.
Zusammenfassung Eine Strukturuntersuchung auf Grund zweidimensionaler Fouriermethoden bestätigt für die Hornblende aus dem eklogitischen Gestein von Stramez die vermutete kristallchemische Formel, wobei sich die Position A in 10-Koordination als besetzt erweist. Außerdem ist für die 6-koordinierten Kationen eine nichtstatistische Besetzung der Atomlagen wahrscheinlich.
Mit 1 Textabbildung
Herrn Professor Dr.F. Machatschki zum 70. Geburtstag gewidmet 相似文献
Summary An investigation by two-dimensional Fourier methods of a hornblende, occurring in eclogitic rocks at Stramez, Saualpe, confirms an atomic arrangement, which shows the 10-coordinated position A being occupied. For the cations in 6-coordination a nonstatistical distribution may be assumed.
Mit 1 Textabbildung
Herrn Professor Dr.F. Machatschki zum 70. Geburtstag gewidmet 相似文献