Quantum harmonic oscillator model for simulation of intercity population mobility

The simulation of intercity population mobility helps to deepen the understanding of intercity population mobility and its underlying laws, which has great importance for epidemic prevention and control, social management, and even urban planning. There are many factors that affect intercity population mobility, such as socioeconomic attributes, geographical distance, and industrial structure. The complexity of the coupling among these factors makes it difficult to simulate intercity population ...     

Numerical Simulation Study on the Effect of Horizontal Well Reservoir Stimulation for Gas Hydrate Production

A new gas hydrate reservoir stimulation method of in-situ fracturing with transient heating is proposed, in line with analysis of the technological bottlenecks faced by marine gas hydrate production. This method injects the developed chemical reagents into a hydrate reservoir through hydraulic fracturing, releasing heat during the chemical reaction to increase the hydrate decomposition rate. The chemical reaction product furthermore has a honeycomb structure to support fractures and increase reservoir permeability. Based on the geological model of natural gas hydrate in the South China Sea, three development methods are simulated to evaluate hydrate production capacity, consisting of horizontal well, fractured horizontal well and in-situ fracturing with transient heating well. Compared with the horizontal well, the simulation results show that the cumulative gas production of the fractured horizontal well in one year is 7 times that of the horizontal well, while the cumulative gas production of in-situ fracturing with transient heating well is 12 times that of the horizontal well, which significantly improves daily efficiency and cumulative gas production. In addition, the variation patterns of hydrate saturation and temperature-pressure fields with production time for the three exploitation plans are presented, it being found that three sensitive parameters of fracture conductivity, fracture half-length and fracture number are positively correlated with hydrate production enhancement. Through the simulations, basic data and theoretical support for the optimization of gas hydrate reservoir stimulation scheme has been provided.     

Analysis on the Characteristics of the Coseismic Response of Water Levels Recorded in Three Wells in Hainan,China to the Two Sumatra-Andaman Strong Earthquakes

The characteristics of seismic water level fluctuations of the two Sumatra-Andaman strong earthquakes with magnitude 8.7 and 8.5 on December 26,2004 and March 29, 2005 recorded at Jiaji well, Qionghai, Hainan were analyzed, the features of the infrequent ＂step＂ changes of well water level after the two earthquakes were also analyzed and the mechanism of the ＂step change＂ of well water level was discussed. Then the high-sample-rate digital observation data of seismically-induced water level fluctuations of the Sumatra-Andaman strong earthquakes with magnitude 8.7 and 8.5 recorded at Nanbin well, Sanya and Tanniu well, Wenchang were analyzed. The results suggest that the dominant period of the seismic well water level fluctuation in all three wells was comparatively accordant, the amplitudes of seismic water level fluctuation of the same earthquake in different wells were clearly different, the time duration of seismic water level fluctuations of different earthquakes at the same well was also clearly different.     

Modern pollen rain in the Lake Qinghai basin,China

Lake Qinghai is the largest inland brackish lake in China and lies within the NE Tibetan Plateau. Our study shows that pollen assemblages in each vegetation belt are significantly correlated with the vegetation types of this area. Among the herbaceous and shrubby pollen assemblages, Artemisia is over-represented, while Poaceae, Cyperaceae and Polygonaceae are under-represented. Artemisia/ Chenopodiaceae (A/C) ratios with the regional vegetation characteristic can be used as a proper index to reconstruct the...     

Exploration and Study of Major Faults in Anshan City,Liaoning Province

In order to provide a basis for the earthquake resistance protection zoning of Anshan City, westudied the activity of faults. In the study, the synthetic geophysical prospecting techniqueswere used. These techniques include the shallow artificial earthquake method, electric method,geologic radar method, etc., with shallow artificial earthquake sounding as the main means.In the meantime, the data of geophysical prospecting and borehole record of this city werecollected and the methods of field investigation and sample age dating were also used incombination. The results show that there are 5 hidden or semi-hidden faults in Anshon City.Among these faults, Dashitou-Songsantai fault, Ningyuantun fault and Dayangqi fault trendNW, the middle Pleistotene Tanggangzi fault trends NE, while the early Pleistocene or Pre-Quaternary Ertaizi fault trend NW. According to the definition of active faults, none of thesefaults is active. This paper also discussed the cause for the formation of seriously damagedareas in Ans     

A Numerical Study on Effects of Land-Surface Heterogeneity from ‘Combined Approach’ on Atmospheric Process Part II: Coupling-Model Simulations

Two land surface schemes, one the standard Biosphere / Atmosphere Transfer Scheme Version le (B0Z) and the other B1Z based on B0Z and heterogeneously-treated by ‘combined approach’ , were coupled to the meso-scale model MM4, respectively. Through the calculations of equations from the companion paper, parameters representing land surface heterogeneity and suitable for the coupling models were found out. Three cases were simulated for heavy rainfalls during 36 hours, and the sensitivity of short-term weath-er modeling to the land surface heterogeneity was tested. Through the analysis of the simulations of the three heavy rainfalls, it was demonstrated that B1Z, compared with B0Z, could more realistically reflect the features of the land surface heterogeneity, therefore could more realistically reproduce the circulation and precipitation amount in the heavy rainfall processes of the three cases. This shows that even short-term weather is sensitive to the land surface heterogeneity, which is more obvious with time passing, and whose influence is more pronounced in the lower layer and gradually extends to the middle and upper layer. Through the analysis of these simulations with B1Z, it is suggested that the bulk effect of smaller-scale fluxes (i.e., the momentum, water vapor and sensible heat fluxes) near the significantly-heterogeneous Land surface is to change the larger-scale (i.e., meso-scale) circulation, and then to influence the development of the low-level jets and precipitation. And also, the complexity of the land-atmosphere interaction was shown in these simulations.     

The influences of boundary layer parameterization schemes on mesoscale heavy rain system

1.Introducti0nThemesoscaleoperationalmodel-whichisoftenused,isMM4orMM5'butMM4isusedfrequentlyonlO3kmscale.Thephysicalprocessesinthismodeldevelopconstantly.FororiginalMM4,thecomputationofsurfacefluxesisnotaccurate,andKmodelfortheturbu-lencefluxesbetweenany2levelsneedstobeimprovedbynewtreatment.Inordertostudytheinfluencesofboundarylayerparameterizationschemesonmesoscaleheavyrainsystem,sur-facefluxesandKmodelinoriginalMM4areimprovedbytherecentresearchinthispaPer.Theflux-profilerelationsforv…     

A Numerical Study on Effects of Land-Surface Heterogeneity from “Combined Approach” on Atmospheric Process Part I: Principle and Method

A method based on Giorgi (1997a, 1997b) and referred to as ‘combined approach’, which is a combination of mosaic approach and analytical-statistical-dynamical approach, is proposed. Compared with those of other approaches, the main advantage of the combined approach is that it not only can represent both interpatch and intrapatch variability, but also cost less computational time when the land surface heterogeneity is considered. Because the independent variable of probability density function (PDF) is extended to the single valued function of basic meteorological characteristic quantities, which is much more universal, the analytical expressions of the characteristic quantities, (e.g., drag coefficient, snow coverage, leaf surface aerodynamical resistance) affected by roughness length are derived, when the roughness length (and/ or the zero plane displacement) heterogeneity has been mainly taken into account with the approach. On the basis of the rule which the PDF parameters should follow, we choose a function y of the roughness length z0 as the PDF independent variable, and set different values of the two parameters width ratio αn and height ratio γ of PDF (here a linear, symmetric PDF is applied) for sensitivity experiments, from which some conclusions can be drawn, e.g., relevant characteristic terms show different sensitivities to the heterogeneous characteristic (i.e., roughness length), which suggests that we should consider the heterogeneities of the more sensitive terms in our model instead of the heterogeneities of the rest, and which also implies that when the land surface scheme is coupled into the global or regional atmospheric model, sensitivity tests against the distribution of the heterogeneous characteristic are very necessary; when the parameterαn is close to zero, little heterogeneity is represented, andαn differs with cases, which have an upper limit of about 0.6; in the reasonable range ofαn, a peak-like distribution of roughness length can be depicted by a small value ofγ, etc..     

A DISCUSSION ON FORMATION AND EVOLUTION OF THE LANCANGJIANG PLATE JUNCTION WITH ANALOGY: WHETHER OR NOT THE LANCANGJIANG OCEAN EXISTED IN LATE PALEOZOIC

A DISCUSSION ON FORMATION AND EVOLUTION OF THE LANCANGJIANG PLATE JUNCTION WITH ANALOGY: WHETHER OR NOT THE LANCANGJIANG OCEAN EXISTED IN LATE PALEOZOIC