The future development of new-type urbanization has drawn great attention from both the government and public alike. In this context, the present study had three related research aims. Firstly, it sought to predict the urbanization and population dynamics in China at both national and provincial levels for the period of 2015 to 2030. Secondly, on this basis, it sought to examine the spatial variation of urbanization given the predicted national urbanization rate of 70.12%. Thirdly, it sought to estimate and evaluate the national and provincial demands of investment in the development of new-type urbanization. The main conclusions from this study were as follows: (1) The population size and urbanization rate will reach 1.445 billion and 70.12%, respectively, from 2015 to 2030. (2) The demographic dividend will vanish when the population pressure reaches its maximum. During this period, there will be 70.16 million urban population born. The suburban population that becomes urbanized will be 316.7 million, and thus the net increase in urban population will reach 386 million. (3) Although the urbanization rate of every Chinese province will increase during 2015–2030, it will do so unequally, while differences in urbanization quality among provinces will also be substantial. In some provinces, moreover, the urbanization quality is not compatible with their eco-social development. (4) A total of 4,105,380 billion yuan is required to fund new-type urbanization and the investment demand for each province varies greatly; for example, Guangdong province requires the most funding, amounting to approximately 148 times that required by Tibet, the province in least need of funding. In the final part of this study, policy suggestions concerning the investment of the new-type urbanization are put forward and discussed. 相似文献
Vicksburg loess is characterized by preferred orientation of constituent grains, which on the average dip 4° toward the west (N 80–85°W). This investigation was undertaken to study, quantitatively, the relationship between natural fabric anisotropies of Vicksburg loess and the orientation of applied stress distribution Results of the study indicate the fabric anisotropies in Vicksburg loess are reflected by definite variation in triaxial shear strength of dry and moist specimens.
In two series of triaxial tests, ultimate strength of the loess is maximum where σ1 is perpendicular to grain orientation, and it is reduced where the principal stresses are 45° to the fabric plane. In this respect, Vicksburg loess may serve as a structural model for granular earth materials in illustrating the influence of fabric on ultimate strength. Moreover, the Mohr-Coulomb fracture line consists of two line segments, with an increase in slope at higher confining pressure. This characteristic suggests that poorly-cemented sands, or sandstones, and silts, or siltstones, may undergo two failures: one at small strains where cement bonds are disrupted and the other at larger strains where internal shearing resistance of granular components is exceeded. 相似文献
The quantitative study of the distribution and taxonomic composition of recent living and dead (without plasma) benthic foraminifers revealed three foraminiferal assemblages in the bottom sediments of the Pacific Ocean at depths of 3350 to 4981 m. The assemblage dominated by the epibenthic Lagenammina difflugiformis, Reophax dentaliniformis, and Saccorhiza ramosa occupies the slopes of underwater hills. The assemblage with a high share of the infaunal Cribrostomoides subglobosum, C. nitidum, and Ammobaculites agglutinans is registered on the abyssal plateau. The assemblage with a significant proportion of the large Astrorhiza and Reophax species, which are characterized by an active way of life, populates gentle slopes and narrow depressions with potentially strong bottom currents. 相似文献
The structure of a stationary sunspot of circular shape is considered. Schluter-Temesvary theory, based on the similarity assumption is criticized. It is shown that this theory does not describe the observed inclination of magnetic field lines in a sunspot. A new assumption is proposed taking into account field lines which return to the photosphere. On the basis of this assumption, the main equation of the new theory is obtained and the results compare well with observations.The National Center for Atmospheric Research is sponsored by the National Science Foundation. 相似文献
Koltjärnen and Nylandssjön are two closely situated lakes (<2 km apart) in northern Sweden. During the past century, distinct varved sediments have formed in these lakes. Nylandssjön has two varved, deep basins. Since lake and catchment characteristics superficially appear very similar for the two lakes and they are exposed to the same climate, one would expect the sediment varves to be similar. This investigation compares the varves in the two deep basins of Nylandssjön, and in the two lakes. The comparison of basins of Nylandssjön shows that varve thickness, water content and annual accumulation rates of organic matter and nitrogen are correlated for the period (1970–2003). The grey-scale curves are only clearly similar in about 50% of the varves. In the between-lake comparison varve thickness, water content and annual accumulation rates of organic matter and nitrogen are correlated for the period (1950–1996). However, the annual accumulation rates of dry mass, minerogenic matter and biogenic silica differ between the lakes, as well as within-varve successions in grey-scale. A general explanation to the differences is that the prerequisites for varve formation are not totally similar because of differences in catchment size, catchment- to-lake material fluxes, lake productivity and land-use influence. This study illustrates the complex relationships that exist between a lake, its catchment, in-lake productivity and formation of sediment varves. As a consequence, we must not apply a too simplistic view of the potential of varves as past climatic indicators, especially if the lakes are affected by land-use. 相似文献
We report the data on changes in snow cover characteristics obtained at meteorological stations Tulun and Bokhan and in their neighborhoods for the period 1961–1990. We examine the changes in snow cover, air temperature and soil temperature at depths of 20, 40 and 80 cm. 相似文献
Aftershock rates seem to follow a power law decay, but the assessment of the aftershock frequency immediately after an earthquake,
as well as during the evolution of a seismic excitation remains a demand for the imminent seismic hazard. The purpose of this
work is to study the temporal distribution of triggered earthquakes in short time scales following a strong event, and thus
a multiple seismic sequence was chosen for this purpose. Statistical models are applied to the 1981 Corinth Gulf sequence,
comprising three strong (M = 6.7, M = 6.5, and M = 6.3) events between 24 February and 4 March. The non-homogeneous Poisson process outperforms the simple Poisson process
in order to model the aftershock sequence, whereas the Weibull process is more appropriate to capture the features of the
short-term behavior, but not the most proper for describing the seismicity in long term. The aftershock data defines a smooth
curve of the declining rate and a long-tail theoretical model is more appropriate to fit the data than a rapidly declining
exponential function, as supported by the quantitative results derived from the survival function. An autoregressive model
is also applied to the seismic sequence, shedding more light on the stationarity of the time series. 相似文献
The stochastic finite element equations for random temperature are obtained using the first-order per-turbation technique taking into account the random thermal properties and boundary condition, based on heat transfer variational principle. The local average method for 2-D is used to discretize random fields. Then, the random temperature fields of embankment in cold regions are investigated on condi-tion that the thermal properties and boundary condition are taken as random fields, respectively, by using the program, which is written by the methods. The expected value of temperature field and the standard deviation of the temperature field of embankment in cold regions are obtained and analyzed. 相似文献
As we are now approaching 2015, both the General Relativity Theory (GRT) and the relativistic Celestial Mechanics based on
it will soon arrive at their 100 year anniversaries. There is no border between Newtonian and relativistic Celestial Mechanics.
The five-decade period of intensive development of Celestial Mechanics in the second half of the 20th century left many interesting
techniques and problems uncompleted. This lecture reviews some problems of Newtonian and relativistic Celestial Mechanics
worthy of further investigation. Concerning Newtonian mechanics, these problems include general solution of the three-body
problem by means of the series of polynomials, construction of the short-term and long-term theories of motion using the fast
converging elliptic function expansions, and representation of the rotation of the planets in the form compatible with the
General Planetary Theory reducing the problem to the combined secular system for translatory motion and rotation. Relativistic
problems considered here include the determination of the main relativistic effects in the motion of a satellite, e.g. the
Moon, and in the rotation of the primary planet using the Newtonian theories of motion and rotation combined with the relativistic
transformation of the reference systems, the use of the linearized weak-field GRT metric as a basis of relativistic Celestial
Mechanics in the post-Newtonian approximation, and the motion of the Solar System bodies at the cosmological background in
the framework of the basic cosmological models. The exposition of the chosen relativistic problems is preceded by reminding
the basic features of relativistic Celestial Mechanics with discussing some present tendencies concerning the Parametrized
Post-Newtonian formalism, International Astronomical Union resolutions, and standardization of the GRT routines. 相似文献