THEORETICAL STUDY ON ALEKSANDROWSKI′S METHOD OF THE GRAPHICAL DETERMINATION OF PRINCIPAL STRESS DIRECTIONS FROM THE FAULT SLIP DATA SETS

A graphical method for determining the principal stress distribution of a triaxial stress state from a fault slipstate was proposed by Aleksandrowski in 1985,based on Arthaud′s concept of plane movement,Alek-sandrowski′s method,however,is only valid for the cases in which the values of the stress ratios(C)are consid-ered 1o be ,10,2,1.1 and 1.Whether the method is applicable for general cases of all values of C has not yetbeen confirmed.In this paper.Aleksandrowskis′ method is tested using a numerical derivation from spatialgeometric analysis,and it is revealed that this method is correct for all values of stress ratios other than C=,10,2,1.1,and 1,i.c-【C【.

THE REGULARITY OF RANDOM GRAPH DIRECTED SELF-SIMILAR SETS

A set in Rd is called regular if its Hausdorff dimension coincides with its upper box counting dimension. It is proved that a random graph-directed self-similar set is regular a.e..

High-Precision Direct Determination of the ^(87)Sr/^(86)Sr Isotope Ratio of Bottled Sr-Rich Natural Mineral Drinking Water Using MC-ICP-MS

Strontium has four naturally occurring stable isotopes,84Sr,86Sr,87Sr,and 88Sr,with abundances of 0.56,9.87,approximately 7.04,and 82.53 atomic %,respectively.The 87Sr/86Sr isotope ratio is variable due to the addition of radiogenic 87Sr produced by the beta decay of 87Rb with a half-life of 4.88 ± 0.05 Ga.Thus,

Exploring the Influencing Factors of FDI in China’s Internal Regions:Evidence From Taiwan

This study aims to explore the influencing factors of the location determinants of Taiwan’s foreign direct investments(FDIs)in China’s internal regions.This study proposes three models to examine the influencing factors of Taiwan’s FDIs in China by combining the location advantages of the host country,the economy and politics of the home country,and network relationship in bilateral and regional trade agreements:First,analyze the location distribution of Taiwan’s FDIs in China’s six regions;Second,analyze the location determinants of Taiwan’s main sectors’(manufacturing and service)FDIs in China;Third,analyze the location determinants of Taiwan’s high-tech industries’FDIs in China’s six regions.The estimated results show that bilateral trade agreement seems to have positive effects on Taiwan’s FDIs in China,while regional trade agreement seems to have negative effects.In Taiwan’s political form,the ruling party with characteristics of political defense against China seems to have negative effects on most of Taiwan’s industries(except manufacturing)and the overall FDIs in China.In terms of China’s relevant economic factors,the main determinants of Taiwan’s high-tech industries’FDIs in the major regions of Eastern and South Central of China are infrastructure and high-level human capital resources.China’s GDP growth and increase in unit labor cost have negative effects on FDIs in most regions of China.This implies that the advantage of low wages in China Factory may gradually decline.This study provides some references and implications for future research and policy makers for the analysis of relevant influencing factors of FDI.

State-Based Determinants of Inward FDI Stock in the U.S. Economy

This paper has empirical character and investigates locational determinants of the inward foreign direct investment （FDI） stock among 50 states of the United States. The analysis uses annual data for the period from 1997 to 2007. The study identifies several state-specific determinants of FDI and investigates the changes in their importance during the study period. Our results show that among the major determinants, the real per capita income, real per capita expenditure on education, FDI related employment, plus real research and development expenditure are found to have a significant positive impact on inward FDI. There is also evidence that manufacturing density and unionization exert a small positive impact on inward FDI. In addition, per capita state taxes, the share of scientists and engineers in the workforce, real capital expenditure, and unemployment rate exert a negative impact on FDI.

Unimolecular Dissociation of H⁺<sub style="margin-left:-6px;">2n+1</sub>Hydrogen Clusters: Measured Cross Sections and Theoretically Calculated Rate Constants

In this paper, we studied the process of dissociation unimolecular of the evaporation of H+2n+1 hydrogen clusters according to size, using the Rice-Ramsperger-Kassel-Marcus (RRKM) theory. The rate constants k(E) were determined with the use of statistical theory of unimolecular reactions using various approximations. In our work, we used the products frequencies instead of transitions frequencies in the calculation of unimolecular dissociation rates obtained by three models RRKM. The agreement between the experimental cross section ratio and calculated rate ratio with direct count approximation seems to be reasonable.

A Study on the Determinants of Location Choice in Inward Foreign Direct Investment （FDI）： Focusing on the Incheon Free Economic Zone

Inward foreign direct investment （FDI） is expected to grow further by virtue of economic globalization. A thorough understanding of the locational determinants of inward FDI will be conducive to enhanced efficiency in attracting direct and SOC-related investments from foreign entities. This study analyzes 51 cases of inward direct foreign investment made in the Incheon free economic zone （IFEZ） from 2002 to 2009 to determine the factors influencing FDI volume, the relevance of locations and the correlation between investment size and location. First, the relationship between the loeational determinants of FDI and the total investment size （total expected project cost） is analyzed. Second, the relationship between the locational determinants of FDI and the FDI is analyzed. Third, the relationship between the locational determinants of FDI and the location choice is analyzed. The results indicate the determinants that influence locations and investment size of FDI entities; whether these factors exercise influence in the zone; and the factors that have relatively significant effects. Ultimately, based on the analytical findings, a few implications for policy and practice are derived.

一种权值直接确定及结构自适应的Chebyshev基函数神经网络

基于函数逼近理论,构造一种Chebyshev基函数神经网络模型。推导出该网络模型的权值直接确定方法,可一步计算出权值,克服了传统BP神经网络学习率选取困难、学习过程冗长和易陷入局部极小等缺点。在此基础上,设计了基于二分搜索的结构自适应算法,根据精度要求自动确定网络最优结构。理论分析及仿真验证均表明,该网络不仅能够快速地完成网络权值确定和结构自适应,且具有优异的学习与逼近能力,而且对随机加性噪声也具有较好的抑制作用。

A Fast and Accurate LEO Satellite-Based Direct Position Determination Assisted by TDOA Measurements

This paper focuses on the trusted vessel position acquisition using passive localization based on the booming low-earth-orbit(LEO) satellites. As the high signal-to-noise ratio(SNR) reception cannot always be guaranteed at LEO satellites, the recently developed direct position determination(DPD)is adopted. For LEO satellite-based passive localization systems, an efficient DPD is challenging due to the excessive exhaustive search range leading from broad satellite coverage. In order to reduce the computational complexity, we propose a time difference of arrival-assisted DPD(TA-DPD) which minimizes the searching area by the time difference of arrival measurements and their variances. In this way, the size of the searching area is determined by both geometrical constraints and qualities of received signals, and signals with higher SNRs can be positioned more efficiently as their searching areas are generally smaller.Both two-dimensional and three-dimensional passive localization simulations using the proposed TA-DPD are provided to demonstrate its efficiency and validity. The superior accuracy performance of the proposed method, especially at low SNRs conditions, is also verified through the comparison to conventional two-step methods. Providing a larger margin in link budget for satellite-based vessel location acquisition,the TA-DPD can be a competitive candidate for trusted marine location service.

Comparison of two different methods for determining flow direction in catchment hydrological modeling

Digital elevation models （DEMs） are widely used to define the flow direction in distributed hydrological models for simulation of streamflow. In recent decades, numerous methods for flow direction determination have been applied successfully to mountainous regions. Nevertheless, some problems still exist when those methods are used for flat or gently sloped areas The present study reviews the conventional methods of determining flow direction for such landscapes and analyzes the problems of these methods. Two different methods of determining flow direction are discussed and were applied to the Xitiaoxi Catchment, located in the Taihu Basin in southern China, which has both mountainous and flat terrain. Both the agree method and the shortest path method use drainage networks derived from a remote sensing image to determine the correct location of the stream. The results indicate that the agree method provides a better fit with the DEM for the hilly region than the shortest path method. For the flat region where the flow has been diverted and rerouted by land managers, both methods require observation of the drainage network to determine the flow direction. In order to clarify the applicability of the two methods, both are employed in catchment hydrological models conceptually based on the Xinanjiang model and implemented with PCRaster. The simulation results show that both methods can be successfully applied in hydrological modeling. There are no evident differences in the modeled discharge when using the two methods at different spatial scales.

Comparison of Direct Microbial Count Procedures for Planktonics and Sessiles Enumeration

In the present investigation, the sensitivity of different direct microbial count procedures applied on systems containing both planktonics and sessiles was tested. The direct count pour plate was compared with direct epifluorescent microscopic enumerations in order to evaluate the efficiency of the studied techniques in giving information about microbial activity or viability. Our results indicate that the standard plate count procedure is the most sensitive method to estimate viable and cultivable planktonic cells. On the other hand, direct enumeration by epifluorescent microscopy may become an interesting alternative to count sessile cells.

Determinants of Antenatal Health Care Utilization in Egypt (2000-2014) Using Binary and Count Outcomes

Aim: This study seeks to investigate the factors determining the utilization of antenatal care services, the frequency of that use, and the timing of receiving antenatal care among Egyptian women utilizing a national representative data from Egypt Demographic and Health Surveys (EDHS) in 2000 and 2014. Methods: The paper estimates the logistic regression model, zero-inflated negative binomial model (ZINB), and negative binomial regression model (NB) to identify the most important determinants of antenatal health care utilization. Results: The findings indicate that the period 2000-2014 has experienced a significant increase in the use of antenatal health care services. The use of the public sector antenatal care services relative to that of the private sector has been decreasing over time. Moreover, wealth index, women’s education and quality of health services play significant roles in increasing accessibility of antenatal health care services. On the other hand, women’s empowerment has shown a positive effect in 2000 only. Conclusion: The study highlights the most vulnerable groups that are less likely to have access to antenatal health care services, mainly women who are less educated, poor and living in rural areas especially Upper Egypt. This certainly requires a more targeted health strategy with an equity lens.

DIRECT DETERMINATION OF NEODYMIUM AND ERBIUM IN RARE EARTH MIXTURE BY DERIVATIVE SPECTROPHOTOMETRY

The absorption spectra of 4f electron transitions of the complexes of neodymium and erbium with 8-hydroxyquinoline-5-sulphonic acid in the presence of diethylamine and ethanol have been measured by normal and third-derivative spectrophotometry. Their molar absorptivities are 70.7 l.mol^(-1).cm^(-1) for Nd and 62.5 l.mol^(-1).cm^(-1) for Er. They are 7.6 times and 14.9 times greater than those of corresponding chlorides, respectively. Use of the third-derivative spectra both eliminates the interference of Ce(Ⅳ) and increases the sensitivity for Nd and Er. Beer,s Law was obeyed from 0-10 ug/ml of Nd and Er. The method has been applied to the determination of neodymium and erbium in rare earth mixtures.

高效液相色谱法同时检测葡萄酒中11种人工合成着色剂

为快速识别葡萄酒中是否添加人工合成着色剂并准确定量,该实验样品采用乙酸铵溶液稀释、8000 r/min离心后直接过滤法进行前处理,梯度洗脱、Zorbax SB-C_(18)柱分离、多波长检测(288 nm、425 nm、515 nm、620 nm),建立了高效液相色谱法(HPLC)同时检测葡萄酒中11种人工合成着色剂的方法。结果表明,该方法前处理简单,各着色剂最大吸收波长检测无杂质干扰、灵敏度高、检出限(0.05 mg/L)、定量限(0.15 mg/L)低,在质量浓度0.20~50 mg/L范围内线性关系良好(R^(2)≥0.9994),方法精密度试验结果的相对标准偏差(RSD)为1.86%~2.61%,加标回收率为93.0%~103.0%。适用于葡萄酒中人工合成着色剂的快速、准确检测。

基于损伤力学的矿用定向钻机金属结构寿命评估

针对ZYL-15000D型煤矿用履带式全液压定向钻机底座寿命评估,首先通过Q345B钢的脉动循环加载拉伸疲劳试验数据,拟合得到应力幅值和寿命的关系式,经由应力修正和安全系数的选取,转换得到对称循环下的应力幅值和寿命的关系式。结合基于损伤力学推导出的损伤退化模型,根据Q345B钢试验数据拟合确定损伤退化模型中的待定参数,将Q345B钢对称循环下应力幅值和寿命的关系式代入,得到Q345B钢的疲劳损伤退化模型。然后借助ABAQUS对钻机整机进行结构分析,得到钻机底座的危险点位置(即应力最大处),在该型号样机试验台上通过应变片测得钻机底座危险点处的应力—时间历程。最后采用雨流计数和应力修正,对测得的随机载荷谱进行处理得到雨流计数直方图(应力均值-幅值-循环次数),再转换为对称循环载荷的形式,代入确定的疲劳损伤退化模型中,评估钻机底座的疲劳寿命。

星载测向系统的测向误差及其定位误差计算方法

针对星载测向系统可通过单次测向实现对地面/海面辐射源瞬时定位的特点,基于星载测向系统的定位模型,推导任意二维阵型的相位干涉仪测向误差表达式。分别从方位角与俯仰角以及空间夹角详细推导了单星测向定位误差公式,并结合球面约束推导单星直接定位的误差表达式。数值仿真表明,基于测向角度的定位误差计算方法结果逼近理论误差值,从而可基于任意二维测向阵型,快速评估卫星观测区域内的测向误差及其定位误差,而单星直接定位相较于测向定位,定位误差显著降低。

卫星导航多干扰源直接定位方法

卫星导航信号到达地面时非常微弱,容易受到各种干扰,给用户带来一定的影响;针对此种情况,面向卫星导航系统多干扰源定位场景,传统两步定位算法受参数估计精度影响较大,DPD_MVDR算法虽然改进了MUSIC算法需要估计目标数这一缺点,但由于使用固定网格分辨率,定位精度与计算复杂度二者无法兼得;针对上述问题,提出一种改进DPD_MVDR的直接定位方法,在直接定位这一关键技术上运用自适应网格细化,其最大优势在于只对干扰源位置附近的网格实现多级细化,能很好地兼顾定位精度与计算复杂度,避免了传统穷举搜索带来的巨大计算复杂度;首先使用DPD_MVDR算法在粗网格下进行位置初始估计,然后在估计位置处进行迭代自适应网格细化,在降低计算复杂度的同时,提高定位精度;仿真表明,改进算法在100 m网格分辨率下计算复杂度明显降低且较DPD_MVDR算法定位精度得到明显提高;适用于对定位精度和定位实时性均有一定要求的场景。

Comparative Analysis of the Determinants of China's State-owned Outward Direct Investment in OECD and Non-OECD Countries

Chinese outward direct investment （ODI） is expanding at an unprecedented rate. The present study augments the understanding of the determinants and drivers of Chinese ODI. It reviews the literature on Chinese 0191 and analyzes investment by state-owned enterprises （SOE） for the period 2003-2008, focusing specifically on the differences between the determinants of Chinese investment in developed （OECD） and developing （non-OECD） economies. In addition, the study assesses the appropriateness of the general framework used for investigating ODI determinants （Dunning＇s eclectic paradigm） to analyze the experience of Chinese SOE. The findings indicate that Dunning＇s eclectic paradigm provides an excellent theoretical framework for analyzing the determinants of Chinese SOE investment in developed countries, and provides a good starting point for analysis of Chinese investment in developing countries. However, Dunning＇s specification requires refinement for developing countries. This paper finds a distinct difference between the motivations for Chinese SOE investment in developed and developing countries.

基于角速度信息先验的固定无源单站直接定位方法

针对传统两步定位法在固定无源单站定位精度不高的问题,提出一种基于角速度先验的固定无源单站直接定位方法 .首先,给出定位场景及辐射源运动模型,根据雷达辐射源脉内、脉间以及空间采样特点,按照快时间、慢时间、快拍构建三维观测信号模型.将快时间变换至频域并提取一组最强信号,利用本文提出的空时对称自相关函数(Space Time Symmetric Autocorrelation Function,STSAF),消除影响定位精度的多余相位项;然后,将经上述处理的2次观测信号进行混频,构建定位模型并给出直接定位代价函数;同时,针对性提出一种基于位置选择的MUSIC(MUltiple SIgnal Classification)算法,根据慢时间域包含的距离信息及空间域包含的方位信息,对辐射源横、纵坐标进行搜索,实现对辐射源的直接定位.本文对算法计算复杂度和克拉美罗下界(Cramer-Rao Lower Bound,CRLB)进行了理论推导,分析了影响定位精度的因素,对比所提直接定位方法与传统两步定位法的均方根误差,绘制本文方法的GDOP(Geometric Dilution Of Precision)曲线.

改进实值空时子空间数据融合的单星直接定位方法

辐射源直接定位是一种能够直接从原始采样信号中估计出辐射源位置的无源定位技术。利用单颗卫星对地球表面固定辐射源进行直接定位具有定位精度高、灵活性强等特点,因而具有重要的研究价值。然而,传统空域子空间数据融合直接定位方法缺乏对多普勒信息的充分利用,其在单星直接定位场景下的定位性能不足。现有空时子空间数据融合直接定位方法提升了该场景下的定位性能,但其仍存在低信噪比条件下定位精度和分辨率不足的问题。针对这些问题,该文提出了一种改进实值空时子空间数据融合的单星直接定位方法,实现了辐射源高程已知条件下单星对多辐射源的直接定位。首先,该文基于WGS-84地球椭球面模型建立联合到达角和多普勒频率的空时信号模型,充分利用了卫星相对辐射源高速运动产生的多普勒频移信息。随后,该文引入了托普利兹矩阵调整方法,对空时信号模型中接收信号的协方差矩阵进行分块,然后对分块矩阵进行调整,并使用前后向平滑和空时子空间酉变换技术来得到实值的空时子空间。最后,该文融合多个时隙的空时子空间数据建立定位的代价函数,同时设计出符合特征空间思想的分子函数,得到改进的代价函数,再通过网格搜索方法估计出辐射源的位置。仿真结果表明:所提方法在低信噪比下相比MUSIC(Multiple Signal Classification)直接定位方法、MVDR(Minimum Variance Distor tionless Response)直接定位方法、ML(Maximum Likelihood)直接定位方法和U-ST-SDF(Unitary Space-time Subspace Data Fusion)方法具有更好的定位性能。