三维体目标间拓扑关系与方向关系的混合推理

重点研究了三维空间中拓扑关系和方向关系间的混合空间关系推理。用Allen区间关系对描述基于投影的空间划分方法得到的方向区域和用九交矩阵描述的拓扑关系,用定义法研究混合空间关系推理,推理结果用组合推理表表示。     

混合表面活性剂存在下镓与O—Cl—PF显色反应的研究

本文研究了在pH 6.5-7.8的(CH_2)_6N_4-HCl缓冲介质中,CDMAA和TritonX-100对Ga与o-Cl-PF和F~-显色反应的增敏作用。结果表明,Ga-o-Cl-PF-F-CDMAA-TritonX-100多元配合物λ_(max)为565nm,表观摩尔吸光系数ε=1.74×10~5L·mol~(-1)·Cm~(-1),Ga含量在0～6.0μg/25ml范围内符合比尔定律,用合成样和标样进行本方法考验,结果满意。     

Steady Response of a Ventilated Thermocline to Enhanced Ekman Pumping

The steady response of the ventilated thermocline to an increase in Ekman pumping is investigated, focusing on the effect of the mixed layer depth distribution on the subsurface density anomaly. We consider only the subtropical gyre, and the mixed layer is assumed to be deep in the northwest and shallow elsewhere with a narrow transition zone separating the deep and shallow mixed layer regions. At the intersection of this narrow transition zone and the outcrop line, low potential vorticity fluid is subducted into and ventilates the thermocline. In such a situation, an enhancement of the Ekman pumping confined to the northern subtropical gyre leads to pronounced subsurface cold anomalies in the southern subtropics, which is free of anomalous forcing. These density anomalies are much greater than those that occur when either the mixed layer depth is zonally uniform or the Ekman pumping is enhanced in the whole subtropical gyre. They are caused by anomalous changes in the trajectory of the low potential vorticity fluid in response to anomalous Sverdrup flow. This revised version was published online in July 2006 with corrections to the Cover Date.     

高水速凝材料-软土微观结构的SEM研究

高水速凝材料是一种新型的固体混合材料,它与普通硅酸盐水泥相比有许多独特的特点：(1) 水用量大;(2) 速凝早强;(3) 可泵时间长;(4) 良好的塑性特性;(5) 极限荷载后强度具再发展性能。虽然,高水速凝材料在煤炭和冶金系统得到了较广泛的应用,取得了较好的技术经济效益,然而,在其它领域还未曾应用过。为了探索高水速凝材料在软土地基方面的应用前景,笔者采用扫描电镜研究了高水速凝材料-软土凝固体的微观结构。研究结果表明,纯土的土颗粒之间只有原生矿物的几何堆积,而没有牢固的连接。但由于高水速凝材料的加入,彻底改变了土体结构。在高水速凝材料-软土凝固体中,主体结构为钙矾石结晶体形成的“空间网状结构”;辅助结构为在碱性环境中土颗粒之间的离子交换、团粒化作用和碳酸化作用所形成的微晶体与凝胶体结构。因此,高水速凝材料在地基处理方面具有较好的应用前景。     

混合型单调算子对的不动点研究及其在微分方程组的应用

提出了混合型单调算子对的概念,并给出了其不动点的存在唯一性;研究了它在微分方程组的具体应用.     

粉喷桩的应用研究综述

粉喷桩具有低污染、低噪音、有效实用、施工简便快捷、施工工期短、技术效果好和费用底等特点而受到普遍关注,但其也存在一定的不足。本文分析了粉喷桩在工程中应用的研究现状,介绍了粉喷桩与其他工程措施相结合的实例,并对以后的研究方向提出了看法。     

供水管井允许出水量的合理确定

每一眼管井在井结构确定的条件下,有一个最大允许出水量,而盲目追求增大出水量,势必造成管井涌砂,过滤管腐蚀和堵塞的加剧。松散含水层供水管井允许出水量既要满足地下水允许开采量“宏观”定义要求,从供水管井使用寿命考虑又要满足管井两个流速参数:井壁允许进水流速和滤管允许进水流速。本文给出了管井允许出水量确定方法和计算框图,并以实例说明之,在具体应用时某些细节也予以了说明。     

Mixing caused by lateral internal seiching within a partially mixed estuary

The salinity fluctuations at an STD near the halocline in Southampton Water have been spectrally analysed. Mixing is shown to commence at a layer Richardson number of about 20. The predominant energy inputs have periods of 7–9 and 3·5–4·5 min. These motions arise from lateral internal seiching and it is considered that they are produced by interaction of the surface seiche with the shallow side of the estuary. The wavelengths of the standing wave are calculated to be about 120 and 60 m respectively, and these compare well with echo-sounding surveys of the elevation of the halocline.     

IMPACT OF DIABATIC PROCESSES IN AGCM ON 4-DIMENSIONAL VARIATIONAL DATA ASSIMILATION*

The impact of diabatic processes on 4-dimensional variational data assimilation (4D-Var) was studied using the 1995 version of NCEP's global spectral model with and without full physics.The adjoint was coded manually.A cost function measuring spectral errors of 6-hour forecasts to "observation" (the NCEP reanalysis data) was minimized using the L-BFGS (the limited memory quasi-Newton algorithm developed by Broyden,Fletcher,Goldfard and Shanno) for optimizing parameters and initial conditions.Minimization of the cost function constrained by an adiabatic version of the NCEP global model converged to a minimum with a significant amount of decrease in the value of the cost function.Minimization of the cost function using the diabatic model, however,failed after a few iterations due to discontinuities introduced by physical parameterizations.Examination of the convergence of the cost function in different spectral domains reveals that the large-scale flow is adjusted during the first 10 iterations,in which discontinuous diabatic parameterizations play very little role.The adjustment produced by the minimization gradually moves to relatively smaller scales between 10-20th iterations.During this transition period,discontinuities in the cost function produced by "on-off" switches in the physical parameterizations caused the cost function to stay in a shallow local minimum instead of continuously decreasing toward a deeper minimum. Next,a mixed 4D-Var scheme is tested in which large-scale flows are first adiabatically adjusted to a sufficient level,followed by a diabatic adjustment introduced after 10 to 20 iterations. The mixed 4D-Var produced a closer fit of analysis to observations,with 38% and 41% more decrease in the values of the cost function and the norm of gradient,respectively,than the standard diabatic 4D-Var,while the CPU time is reduced by 21%.The resulting optimal initial conditions improve the short-range forecast skills of 48-hour statistics.The detrimental effect of parameterization discontinuities on minimization was also reduced.     

Relationships among some locally conservative discretization methods which handle discontinuous coefficients

This paper presents the relationships between some numerical methods suitable for a heterogeneous elliptic equation with application to reservoir simulation. The methods discussed are the classical mixed finite element method (MFEM), the control-volume mixed finite element method (CVMFEM), the support operators method (SOM), the enhanced cell-centered finite difference method (ECCFDM), and the multi-point flux-approximation (MPFA) control-volume method. These methods are all locally mass conservative, and handle general irregular grids with anisotropic and heterogeneous discontinuous permeability. In addition to this, the methods have a common weak continuity in the pressure across the edges, which in some cases corresponds to Lagrange multipliers. It seems that this last property is an essential common quality for these methods. T.F. Russell: Partially supported by the National Science Foundation Grant Nos. DMS-0084438 and DMS-0222300.