深度优先搜索的地图着色算法

在分析地图着色本质以及深度优先搜索算法优缺点基础上,本文提出一种基于深度优先搜索的地图着色方法,并以全国地图和全国县级行政区划图对本文算法进行了实验验证,取得了较好的着色结果.     

Three‐dimensional modal pushover analysis of buildings subjected to two components of ground motion,including its evaluation for tall buildings

The modal pushover analysis (MPA) procedure, presently restricted to one horizontal component of ground motion, is extended to three‐dimensional analysis of buildings—symmetric or unsymmetric in plan—subjected to two horizontal components of ground motion, simultaneously. Also presented is a variant of this method, called the practical modal pushover analysis (PMPA) procedure, which estimates seismic demands directly from the earthquake response (or design) spectrum. Its accuracy in estimating seismic demands for very tall buildings is evaluated, demonstrating that for nonlinear systems this procedure is almost as accurate as the response spectrum analysis procedure is for linear systems. Thus, for practical applications, the PMPA procedure offers an attractive alternative whereby seismic demands can be estimated directly from the (elastic) design spectrum, thus avoiding the complications of selecting and scaling ground motions for nonlinear response history analysis. Copyright © 2010 John Wiley & Sons, Ltd.     

流体包裹体成分物理化学参数的NET2.0C#语言计算程序

根据地球化学热力学原理,利用流体包裹体成分测试数据和有关热力学原理,在原有基础上采用NET2.0 C#语言进行修编,编制成目前切实可行的计算机处理程序——矿物包裹体成分、物理化学参数的计算程序.其目的是方便广大地质工作者将这些参数用于地质找矿和科学研究中.     

太平洋侧花海葵的营养成分分析

本文测定了太平洋侧花海葵中的蛋白质、脂肪和无机元素等营养成分,分析了太平洋侧花海葵中构成蛋白质的17种常见氨基酸和主要脂肪酸含量。结果表明,太平洋侧花海葵是一种高蛋白、低脂肪的海产品;必需氨基酸和鲜味氨基酸的含量较高,但必需氨基酸之间的比值不太符合人体的氨基酸平衡,宜与其他食物搭配食用。各类脂肪酸中,油酸(18∶1)含量最高,其次为C22∶2。无机元素丰富,尤其是Zn,含量可达254.4 mg/kg。     

亚洲新兴经济体服务贸易竞争力比较研究——基于亚洲“四小龙”服务贸易数据分析

本文采用服务贸易国际竞争力常用评价指标体系,对亚洲新兴经济体一亚洲“四小龙”的服务贸易国际竞争力进行了比较分析。研究表明：中国香港的服务贸易国际竞争力最强,优势部门为运输和金融;新加坡服务贸易发展最为迅速;中国台湾和韩国服务贸易处于较低水平,但韩国的政府服务遥遥领先,建筑业已处于世界先进水平。在此基础上,提出应加强亚洲“四小龙”的服务贸易合作,形成优势互补,提高国际竞争力。     

中国“四极”区域旅游合作发展模式研究

在区域旅游合作内容与方式不断发生变革的今天,“中国四极”区域旅游合作框架的提出可谓是一种全新的构想,其不仅可对“四极”地区各自独特的旅游资源进行有效的整合,进而形成既内容丰富又极具特色的完整的旅游品牌;同时这种基于大尺度空间及时间背景下的合作也必然会带来其与相关线路、相关区域之间的旅游协作,从而带动更大区域范围内旅游业的发展。本文从中国“四极”合作开发的可行性分析入手,探讨了中国“四极”合作的发展模式、合作内容和运行机制等方面的问题。     

Wharf embankment and strengthening program at the Port of Oakland

The wharf and embankment strengthening program (WESP) is a structural modification project involving approximately 12,000 linear feet of pile-supported, marginal wharf structures. WESP is necessary because the Port of Oakland plans to deepen its berths from −42′ mean lower low water (MLLW) to −52′ MLLW, in conjunction with a Federal Government-sponsored channel dredging project. Unless they are structurally reinforced prior to the dredging, the waterfront components (i.e. wharves and embankments) will be weakened by the berth deepening project. WESP is a three-phase program that establishes the existing structural and seismic capacities of waterfront components, develops designs for improvements necessary to maintain these capacities after the berth deepening, and constructs the improvements. WESP also includes consideration of seismic upgrade improvements. The Port is currently completing the first phase of the WESP program. This paper will describe the design criteria, project phasing, construction type of waterfront components, project organization, and results to date for WESP.     

Multivariate statistical analysis of geochemical data as indicative of the hydrogeochemical evolution of groundwater in a sedimentary rock aquifer system

The study of groundwater hydrogeochemistry of the Paleozoic Basses-Laurentides sedimentary rock aquifer system in Québec produced a large geochemical dataset. Groundwater samples were collected at 153 sites over a 1500 km² study area and analyzed for major and minor ions. The large number of data can lead to difficulties in the integration, interpretation and representation of the results. Two multivariate statistical methods, hierarchical cluster analysis (HCA) and principal components analysis (PCA), were applied to a subgroup of the dataset to evaluate their usefulness to classify the groundwater samples, and to identify geochemical processes controlling groundwater geochemistry. This subgroup consisted of 144 samples and 14 parameters (Ca²⁺, Mg²⁺, Na⁺, K⁺, , Cl⁻, , Fe²⁺, Mn²⁺, Br⁻, Sr²⁺, F⁻, Ba²⁺, HS⁻). Seven geochemically distinct clusters, C1–C7, resulted from the HCA. Samples from clusters C3, C4, C6 and C7 are mostly located in preferential recharge areas. The majority of these samples have Ca–Mg–HCO₃ recharge groundwater (C3, C6, C7) and Na–HCO₃ evolved groundwater (C4). Samples from the other three clusters (C1, C2, C5) are characteristic of an aquifer system under confined conditions. The majority of these samples have Na–HCO₃ evolved groundwater (C1, C5) and Na–Cl ancient groundwater that exhibits elevated concentrations in Br⁻ (C2). In addition to recognizing the importance of hydrogeological conditions on groundwater geochemistry, the distribution of clusters also showed the importance of the geological formations on minor and trace elements, such as Fe²⁺, Mn²⁺, Sr²⁺, F⁻ and Ba²⁺. The first five components of the PCA account for 78.3% of the total variance in the dataset. Component 1 is defined by highly positive loadings in Na⁺, Cl⁻ and Br⁻ and is related to groundwater mixing with Champlain Sea water and solute diffusion from the marine clay aquitard. The high positive loadings in Ca²⁺ and Mg²⁺ of component 2 suggest the importance of dissolution of carbonate rocks in this aquifer system. From their characteristic loadings, the first two components are defined as the “salinity” and “hardness” components, respectively. Components 3–5 are related to more local and geological effects. The integration of the HCA and the PCA, with conventional classification of groundwater types, as well as with the hydrogeological and geological contexts, allowed the division of the region into four main geochemical areas, providing an improved regional picture of the aquifer system dynamics and hydrogeochemical evolution of groundwater. The following factors were recognized as influencing the evolution of groundwater identified in every geochemical area: (1) geological characteristics including sedimentary rock type and till mineralogy; (2) hydrogeological characteristics represented by the level of confinement and the hydraulic gradient; and (3) the geological history including the latest glaciation and the Champlain Sea invasion. With its integrated approach, this hydrogeochemical study contributes to the characterization and understanding of complex groundwater flow systems, and provides an example of the long-term geochemical evolution of hydrogeological systems after a major perturbation, in this case seawater invasion.     

小波包去噪在地震信号预处理中的应用

本文将小波包去噪应用于地震信号的预处理中,并与信号功率谱分析相结合,取得了良好的效果。结果表明,该方法极大的削弱了地震信号中的高、低频干扰,具有一定的应用价值。     

Determination of thermal maturity and organic matter type by principal components analysis of the distributions of polycyclic aromatic compounds

The thermal maturity and organofacies sensitivity of polycyclic aromatic compound (PAC) distributions was explored by examination of the aromatic fractions of solvent extracts from a diverse set of 53 shales, coals and kerogen macerals which have undergone either natural or artificial maturation and which represent all three principal sedimentary organic matter (OM) types. Systematic changes with maturation were observed in the following groups of isomers: tri- and tetramethylnaphthalenes, methyl- and dimethylphenanthrenes, methyl- and dimethyldibenzothiophenes, methylpyrenes, and methylchrysenes. The maturity differences were quantified by mathematical ratios of the relative concentrations of the more thermally stable isomers to the less stable, on the basis of theoretical considerations and empirical observations. The PAC maturity parameters, unlike those derived from saturated biomarker stereoisomers, are typically effective across the entire oil generation window. To compensate for the effects of OM type on the maturity parameters, they were combined using principal components analysis. The resulting first principal component was in good agreement with independent indicators of maturity. The relative distributions of C₀–C₃ alkylphenanthrenes, dibenzothiophene, methyldibenzothiophenes and methyldibenzofurans were evaluated by a separate principal components analysis. The results permitted an independent grouping of the samples by OM type and suggested additional, simple molecular ratios that allow graphical recognition of OM type, including the ratio of dibenzothiophenes to dibenzofurans and a ratio using C₂-alkylphenanthrene isomers.