Mathematical Models for Combined Refraction-Diffraction of Waves on Non-Uniform Current and Depth

Two mathematical models for combined refraction-diffraction of regular and irregular waves on non-uniform current in water of slowly varying topography are presented in this paper. Model I is derived by wave theory and variational principle separately. It has two kinds of expressions including the dissipation term. Model n is based on the energy conservation equation with energy flux through the wave crest lines in orthogonal curvilinear coordinates and the wave kinematic conservation equation. The analysis and comparison and special cases of these two models are also given.     

Fractal-like adsorption kinetics of Pb^2＋ in rocks

The adsorption kinetics of Pb^2＋ in rocks has been studied using ion selective electrodes and atomic absorption spectrophotometer. The results showed that the adsorption process is a fractal-like reaction. The adsorption rate was relatively high before 30 minutes, and then dropped. The saturated adsorption capacity （a） of Pb^2＋ and kinetic parameters （b, a, D and k） increased with increasing initial concentrations of Pb^2＋. These parameters （except a） decreased while Na^＋ was present in the solution. Furthermore, the smaller the rocks were in grain size, the bigger these kinetic parameters would be, though the parameter a was almost constant.     

MODELING STUDY ON SEDIMENTATION CONFIGURATION IN FRONT OF THE DAM AND IN THE PRESSURE CONDUIT OF BOTTOM OUTLETS BY FLUME EXPERIMENT

I.INTRODUCTIONReseri,oirsonoverloadedriverswillreachthestateofrelativeequilibriumwithcontinuousdevelopmentofsedimentation.Insuchcase,thereisdePOsitinfrontofthedam.Thereforethesiltpressureonthedambodyisconsiderablylarge.Sedimentationelevationinfrontofthedamisoneofthefactorsofcalculatingthesiltpressure.Inaddition,tokeeplong-termworkingstorageinreservoif,itisnecessarytoinstallbottomoutlets.Asthereisapressureconduitinfrontoftheoperatinggateofthebottomoutlet,thesedimelltenteredtheconduitwill…     

再论各向异性介质转换波地震学,第一部分:理论

我们业已研发了计算各向异性、非均质介质中P- SV转换波(C-波)的转换点和旅行时的新理论。据此 可以利用诸如相似性分析、迪克斯模型建模、克契 霍夫求和等常规方法来完成各向异性的处理和各向 异性处理,并使各向异性的处理成为可能。这里将 我们的新发展分作两部分来介绍。第一部分为理 论,第二部分为对速度分析和参数计算的应用。第 一部分理论包括转换点的计算和动校正的分析。     

Water soluble components of PM10 Chongqing, China

The concentrations of water soluble ions (Na⁺, NH₄ ⁺, K⁺, Mg²⁺, Ca²⁺, NO₃ ^-, Cl^-, and SO ₄ ^2- ) in PM₁₀ samples collected on cellulose filters by a medium-volume cascade impactor were determined, which were obtained from three kinds of areas in Chongqing: industrial area (Jiulongpo district), commercial and residential area (Jiangbei district) and background area (Jinyun Mountain in the Beibei district). The results showed that except for the background site, the annual average values of PM₁₀ are 23% – 61% higher than the national air quality standard (GradeII) (0.1 mg/m³), even that the value of the control site is still 20% higher than American standard (0.05 mg/m³). This implied that serious pollution of fine particles occurred in Chongqing. Nine kinds of soluble ions in water of PM₁₀ were analyzed by ion chromatography (IC) and the annual average concentrations follow the order of [SO ₄ ^2- ] > [NO³ _-] > [Cl^-] > [F^-], and [Ca²⁺] > [NH₄ ⁺] > [K⁺] > [Na⁺] > [Mg²⁺]. Their values were different in these areas: the industrial area > the commercial and living area > the control area. As for NH_{4 +}, K⁺, Ca²⁺, NO₃ ^- and SO ₄ ^2- , their seasonal average concentrations show a similar variation trend: the values in spring and fall were higher than those in summer and winter. The seasonal average concentrations of [Cl^-], [F^-], [Na⁺] and [Mg²⁺] are much lower than those of other ions. However, the concentrations of [Na⁺] changed more greatly in different seasons than those of the other three ions. Correlation coefficients showed that the three areas have been polluted by coal smoke and dust to different extents, while some local resources of pollution should be taken into consideration as well.     

风积沙环境下高等级公路冻土块石路基降温性能分析

青藏高原脆弱的生态系统以及人类工程活动,加剧了青藏工程走廊线性工程两侧沙漠化、荒漠化发展趋势,尤其冻土块石路基面临日益严重的风积沙灾害问题。以多年冻土区高等级公路块石路基为研究对象,采用数值模拟分析风积沙环境下封闭块石路基的降温性能和长期热稳定性。结果表明：风积沙堆积对封闭块石路基下部土层冻土温度的影响程度高于冻土上限,1.0 m湿沙工况降低冻土温度,0.2 m干沙则增大冻土温度。升温背景下,随年平均气温增加风沙堆积对路基冻土上限影响程度增强,干沙增大冻土融化深度,湿沙抬升冻土上限。随冻土含冰量减小,路基中心冻土上限对气候升温敏感性增加,风沙堆积影响减弱。气候升温和风沙堆积条件下,在年平均气温低于-5.5℃时,宽幅沥青路面封闭块石路基能够满足降温要求,使人为冻土上限保持在块石层内。研究成果可为风沙危害区多年冻土块石路基的病害治理和拟建青藏高速公路块石路基设计提供科学依据。     

一种新的地图数据检索方法及其应用软件

本文提出了一种新的实用地图数据检索方法——“放大镜”式地图数据检索,建立了相应的软件系统,并讨论了该方法的数学基础、软件的特点,还给出了应用实例。     

以可区分度量为准则进行变形监测网的优化设计

本文采用变形模型可区分度量的概念进行监测网的优化设计。在算法上采用计算机模拟逐一更新的计算过程。为了克服常规模拟法需要人工干预的缺点,引进了一些规则,利用计算机的判断和推理过程,达到了自动设计的目的。作为示范例子,文中最后还给出了一个模拟监测网的设计结果。     

CCD相机二维几何检校

CCD 相机检校是 CCD输入影象处理的一个必不可少的过程。本文对 CCD成象系统的几何性能进行了分析,提出了测定 CCD影象象素比例因子和象主点初值的简易实验方法。在此基础上,构造了一种同时顾及光、电误差的二维检校方法,井进行了相机检校实验。最后对检校结果进行了分析和讨论。     

面向对象的语义数据模型及其在空间数据库中的应用

传统的数据库模型适合于表示数字字母数据,难以处理复杂的空间数据。面向对象的语义数据模型克服了传统数据模型的许多不足,越来越多地应用于计算机科学各个领域。本文先描述了面向对象的语义数据模型,然后介绍了建立于这种模型基础上的空间数据库实验系统 spobase。