Comprehensive methods for measuring regional multidimensional development and their applications in China

National and international research on regional development has matured from the use of single elements and indicators to the application of comprehensive multi-element and multi-indicator measures. We selected 12 indicators from six dimensions for analysis in this study, including income, consumption, education, population urbanization, traffic, and indoor living facilities. We then proposed the polyhedron method to comprehensively measure levels of regional multidimensional development. We also enhanced the polygon and vector sum methods to render them more suitable for studying the status of regional multidimensional development. Finally, we measured levels of regional multidimensional development at county, city, and provincial scales across China and analyzed spatial differences using the three methods above and the weighted sum method applied widely. The results of this study reveal the presence of remarkable regional differences at the county scale across China in terms of single and multidimensional levels of regional development. Analyses show that values of the regional multidimensional development index (RMDI) are high in eastern coastal areas, intermediate in the midlands and in northern border regions, and low in the southwest and in western border regions. Districts characterized by enhanced and the highest levels of this index are distributed in eastern coastal areas, including cities in central and western regions, as well as areas characterized by the development of energy and mineral resources. The regional distribution of reduced and the lowest levels of this index is consistent with concentrations of areas that have always been impoverished. Correlation analyses of the results generated by the four methods at provincial, city, and county scales show that all are equivalent in practical application and can be used to generate satisfactory measures for regional multidimensional development. Additional correlation analyses between RMDI values calculated using the polyhedron method and per capita gross domestic product (GDP) demonstrate that the latter is not a meaningful proxy for the level of regional multidimensional development.     

水资源约束下的河西走廊城市经济脆弱性时空演变及其影响因素

城市经济脆弱性作为当前脆弱性研究中的重要领域,为人-地系统耦合研究提供了新的视角,并为城市可持续健康发展提供有益的决策支持和管理方法。依据城市经济脆弱性内涵,基于暴露度、敏感性、适应能力构建了城市经济脆弱性评价指标体系,运用熵权TOPSIS法评价河西走廊地区及区域内五市的城市经济脆弱性,并采用障碍度模型识别影响区域城市经济脆弱性变化的因素。结果显示：（1）2006—2015年,河西走廊地区城市经济脆弱性呈现出先曲折下降（2006—2011年）再波动上升趋势（2012—2015年）;（2）河西走廊地区的城市经济脆弱性具有明显的空间特征,经历了东西高、中部低到整体较高的演变过程;（3）阻碍河西走廊地区城市经济脆弱性降低的障碍因子由适应能力逐步转变为暴露度。针对河西走廊地区各市主要障碍因子,提出针对性优化措施。     

基于全球分布的地震观测数据估计0S0模态的特征频率及品质因子

选取2011-03-11日本MW9.3地震后全球地震台站记录的约220 h波形数据,基于一定的判断准则,筛选出质量较高的448个垂向观测数据,采用频域AR方法对0S0模态的特征频率和品质因子进行估值,并以信噪比为权重进行加权平均,得到特征频率f=0.814 658 4±5.3×10-7,品质因子Q=5 586±12。该结果与已有研究成果相比精度更高,有助于约束现有地球介质密度和衰减模型,使其更接近真实地球。     

基于CEL法的埋深海底管道受坠物撞击损伤分析

海底管道一旦受到坠物撞击损伤,会造成严重的环境污染及经济损失,为保证管道在运行期间的安全性,常对其进行埋深处理。对于有埋深的海底管道,坠物的撞击会造成管道上覆土体的大变形,在数值模拟中会导致网格畸变,甚至无法收敛。耦合欧拉-拉格朗日法(CEL法)可有效处理土体大变形问题,本文基于此方法建立了坠物-管道-土体有限元模型,分析了坠物撞击速度、质量、形状、海床土体性质(弹性模量、内摩擦角、黏聚力)、埋深对海底管道塑性变形的影响。结果表明,管道的凹痕深度随坠物撞击速度和质量的增加而增加;坠物与海床土体及管道接触面积越小,管道的凹痕深度越大;管道的埋置深度及海床土体的性质对吸收坠物的撞击能量有直接关系:海床土体的强度越高、埋深越大,管道所受到的损伤程度越小。分析结果可为管道的设计与防护工作提供科学依据,且与现行规范比较,本文方法更加经济、合理。     

Comparative Analysis of Seismic Response Characteristics of Pile-Soil-Stnicture Interaction System

The study on the earthquake-resistant performance of a pile-soil-structure interaction system is a relatively complicated and primarily important issue in civil engineering practice. In this paper, a computational model and computation procedures for pile-supported structures, which can duly consider the pile-soil interaction effect, are established by the finite element method. Numerical implementation is made in the time domain. A simplified approximation for the seismic response analysis of pile-soil-structure systems is briefly presented. Then a comparative study is performed for an engineering example with numerical results computed respectively by the finite element method and the simplified method. Through comparative analysis, it is shown that the results obtained by the simplified method well agree with those achieved by the finite element method. The numerical results and findings will offer instructive guidelines for earthquake-resistant analysis and design of pile-supported structures.     

Estimating Petroleum Resources Using Geo-Anchored Method--A Sensitivity Study

The Geo-anchored method, based on a moment-type estimator, has been developed for estimating parent population properties from a successive sample of discoveries. By substituting the expectation of the waiting time z _(n+1) of the (n + 1) ^th discovery to occurrence for an unknown parameter in the anchored method, the Geo-anchored method allows estimation of inclusion probabilities directly from observed data, thus eliminating the need for a priori selection of a value of N, R, or some other feature of the parent population. Because direct estimation of N and R requires an ordered sample, the Geo-anchored method is more sensitive to the data-generating process than the anchored method. This paper presents a sensitivity study on the Geo-anchored method. The test is based on simulated discovery sequences with different assumptions regarding discovery efficiency, exploration maturity, and the shape of the parent field size distribution. As a reference for comparison, estimates from the Horvitz–Thompson estimator also are presented.     

Variational iteration solving method for El Nio phenomenon atmospheric physics of nonlinear model

1 IntroductionThe El Ni’o atmospheric physics oscillation is anabnormal phenomenon involved in the tropical Pacificocean- atmosphere interactions. Studies on the El Ni(ophenomenon are very attractive (Lin et al., 2000; Linet al., 2001, 2002; Wang, 2001; Feng et al., 2001;Feng et al., 2002; Liu et al., 2002; Wei and Chen,2003; Xie et al., 2002; Zhu et al., 2002; Pu et al.,2003; Gu et al., 2004; Yu and Liu, 2004). Lin and Mo(2004), Mo and Lin (2004) and Mo et al. (2004) alsostudied a s…     

Numerical and experimental study on hydrodynamic interaction of side-by-side moored multiple vessels

This paper aims to investigate the basic interaction characteristics of side-by-side moored vessels both numerically and experimentally. A higher-order boundary element method (HOBEM) combined with generalized mode approach is applied to analysis of motion and drift force of side-by-side moored multiple vessels (LNG FPSO, LNGC and shuttle tankers). Model tests were carried out for the same floating bodies investigated in the numerical study in regular and irregular waves. Global and local motion responses and drift forces of three vessels are compared with those of calculations. Discussions is highlighted on applicability of numerical method to prediction of sophisticated multi-body interaction problem of which motion behavior is very important to analysis of mooring dynamics of deep sea floating bodies.     

An efficient hybrid integral-equation method for point-absorber wave energy converters with a vertical axis of symmetry

To assist in the prototyping and controller design of point-absorber wave energy converters (WECs), an easy-to-implement hybrid integral-equation method is presented for computing the frequency-domain hydrodynamic properties of bodies with a vertical axis of symmetry in waves. The current hybrid method decomposes the flow domain into two parts: an inner domain containing the body and an outer domain extending to infinity. The solution in the inner domain is computed using the boundary-element method, and the outer-domain solution is expressed using eigenfunctions. Proper matching at the domain boundary is achieved by enforcing continuity of velocity potential and its normal derivative. Body symmetry allows efficient computation using ring sources in the inner domain. The current method is successfully applied to three different body geometries including a vertical truncated floating cylinder, the McIver toroid, and the coaxial-cylinder WEC being developed in the authors’ laboratory. In particular, the current results indicate that, by replacing the flat bottom of the coaxial-cylinder WEC with the Berkeley-Wedge (BW) shape, viscous effect can be significantly reduced with only minor negative impact on wave-exciting force, thus increasing WEC efficiency. Finally, by comparing to experimental measurements, the current method is demonstrated to accurately predict the heave added mass and wave-exciting force on the coaxial-cylinder WEC with BW geometry. If a viscous damping correction factor is used, the heave motion amplitude can also be accurately computed.     

内湾沉积物生物硅化学测定法的实验条件探讨

对国内外已经建立的几种生物硅的测定方法进行简要的评述,并详细地对内湾沉积物中生物硅化学提取法的条件选取进行实验探讨,对低生物硅含量的内湾沉积物测定提出了较优的条件。