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1.
This paper considers the problem of estimatingm, the number of components in a finite mixture of distributions from a parametric family. A step-up procedure using the bootstrap method is proposed. Some properties of the procedure are illustrated with simulation studies. An example of the method, applied to orientation of beach clasts, is given. 相似文献
2.
S.A. Hsu 《Pure and Applied Geophysics》2003,160(1-2):349-355
— Monthly dispersion characteristics for air quality modeling over the South China Sea offshore the west coast of Borneo are studied using long-term ship measurements. It is found from monthly averages that the stability condition is nearly neutral throughout the year with the exception of April, May, and November which are slightly unstable. The lifting condensation level ranged from 338 to 450 m. The lowest value of the ventilation factor occurred in April and the highest in January. The friction velocity for each month is also provided to determine the vertical eddy diffusivity and horizontal and vertical dispersion coefficients. 相似文献
3.
L. C. Hsu 《Contributions to Mineralogy and Petrology》1980,71(4):407-415
The phase relations in the system grossular-spessartine-H2O were investigated at 2.0 Kb aqueous fluid pressure and at subsolidus temperatures down to 420 ° C. Despite metastable persistence of a compositional gap found in some intermediate members, a complete solid solution between grossular and spessartine exists.Linear relations between the unit cell edge, a
0, and composition were readily observed down to 620 ° C with a
0=11.849(2) Å and 11.613(2) Å for grossular and spessartine, respectively. Hydrated garnets began to appear at higher temperature for the Ca-rich members. Grossular and spessartine formed at 420 ° C have a
0=11.901(2) Å and 11.632(2) Å, indicating the presence of 0.6 and 0.2 mol H2O, respectively. Intermediate members show varying degrees of hydration. Infrared spectra of the more hydrated members show a major and minor absorption bands at 3,620 cm–1 and 3,660 cm–1, respectively, in addition to a broad band around 3,430 cm–1. All the hydrogarnets formed at 420 ° C were proven to be metastable.The rare occurrence of the intermediate grossular-spessartine garnets may be attributed to the lack of appropriate bulk chemistry of the rock rather than to the P-T conditions to which the rock is subjected. There may be a stability field for hydrogrossular below 420 ° C at 2 Kb, but not for hydrospessartine. Any occurrence of hydrogarnet may be used as a temperature indicator setting the maximum of formation for the hydrogarnet-bearing assemblage below 420 ° C at 2 Kb. 相似文献
4.
5.
S. A. Hsu 《Boundary-Layer Meteorology》1979,16(3):93-98
Variation exists in the maximum mixing height (MMH) across the coastal zone because of major differences in heat capacity
between land and sea. By assuming that synoptic and microscale effects are all small as compared to the contribution from
mesoscale temperature differences, a model is proposed to explain this variation. The model states that the variation of the
MMH across the coastal zone is due primarily and is linearly proportional to the difference in maximum temperature between
land and sea. Since the MMH is one of the most important parameters in the computation of distribution and concentration of
aerosols, water vapor, and pollutants, a simple equation is also provided for the operational forecasting of the MMH or the
mixing height over the sea. All inputs into the equation are routinely available. The model has been verified by available
data and a relevant field experiment. 相似文献
6.
Spatial heterogeneity is ubiquitous in nature, which may significantly affect the soil hydraulic property curves. The models of a closed‐form functional relationship of soil hydraulic property curves (e.g. VG model or exponential model) are valid at point or local scale based on a point‐scale hydrological process, but how do scale effects of heterogeneity have an influence on the parameters of these models when the models are used in a larger scale process? This paper uses a two‐dimensional variably saturated flow and solute transport finite element model (VSAFT2) to simulate variations of pressure and moisture content in the soil flume under a constant head boundary condition. By changing different numerical simulation block sizes, a quantitative evaluation of parameter variations in the VG model, resulting from the scale effects, is presented. Results show that the parameters of soil hydraulic properties are independent of scale in homogeneous media. Parameters of α and n in homogeneous media, which are estimated by using the unsaturated hydraulic conductivity curve (UHC) or the soil water retention curve (WRC), are identical. Variations of local heterogeneities strongly affect the soil hydraulic properties, and the scale affects the results of the parameter estimations when numerical experiments are conducted. Furthermore, the discrepancy of each curve becomes considerable when moisture content becomes closer to a dry situation. Parameters estimated by UHC are totally different from the ones estimated by WRC. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
7.
This paper studies the continuous evolution of breaking wave for the surface water waves propagating on a sloping beach. A Lagrangian asymptotic solution is derived. According to the solution coupled with the wave breaking criteria and the equations of water particles motion, the wave deformation and the continuous wave breaking processes for the progressive water waves propagating on a sloping bottom can be derived. A series of experiments are also conducted to compare with the theoretical solution. The results show that the present solution can reasonably describe the plunging or spilling wave breaking phenomenon. 相似文献
8.
9.
Te-Hsien Lin Ching-Hua Lo Sun-Lin Chung Fang-Jui Hsu Meng-Wan Yeh Tung-Yi Lee Jian-Qing Ji Yi-Zhau Wang Dunyi Liu 《Journal of Asian Earth Sciences》2009,34(5):674-685
We conducted a comprehensive 40Ar/39Ar geochronological study of the Jiali and Gaoligong shear zones to obtain a better understanding of crustal deformation and tectonic evolution around the Eastern Himalayan Syntaxis (EHS). The new age data reveal that the main phase of deformation in the Jiali and Gaoligong shear zones occurred from 22 to 11 Ma and from 18 to 13 Ma, respectively. Structural data collected during this study indicate that the Jiali shear zone underwent a change in shear sense from sinistral to dextral during its movement history. Based on a comparison with the deformation histories of other major shear zones in the region, we argue that the initial sinistral motion recorded by the Jiali shear zone was coincident with that of the Ailao Shan–Red River shear zone, which marked the northern boundary of the southeastward extrusion of the Indochina block during the Early Miocene. From the Middle Miocene (~18 Ma), the Jiali shear zone changed to dextral displacement, becoming linked with the dextral Gaoligong shear zone that developed as a consequence of continued northward indentation of the Indian continent into Asia. Since this time, the Jiali and Gaoligong shear zones have been united, defining the southwestern boundary of the EHS during clockwise rotation of the eastward-extruding Tibetan block, as revealed by recent GPS data. The temporal change in regional deformation pattern from southeastward block extrusion to clockwise rotation of crustal fragments may have played an important role in the development of the eastern Himalayan drainage system around the EHS. 相似文献
10.
The highest short-crested waves have been studied analytically and numerically by several workers, but without a conclusive view. An efficient numerical scheme is proposed in this paper which retains the water-surface elevations in an implicit form in the governing equations, rather than using a series approximation, thus improving the accuracy of the numerical results. Convergence of the numerical scheme is verified. The almost highest short-crested waves in deep water are then evaluated, which are defined for the condition with the largest wave energies. It is found that the critical angle for wave frequency reversal also demarcates the wave characteristics near breaking, for either kinematic or dynamic prominence. The known results available for the limiting two-dimensional cases of standing and progressive waves are compared favourably. 相似文献