Use of discriminant analysis for classification of strata in sedimentary successions

The technique of instrumental neutron activation analysis (INAA) has been used to analyze chip samples of geological material for 12 elements. Discriminant analysis has been used to classify the unknown chip samples to the correct stratum in a sedimentary succession.     

基于几何形态测量学的4种金线鱼矢耳石识别研究

利用2007年9月至2010年9月采自北部湾海域的24尾红棘金线鱼(Nemipterus nemurus)、32尾金线鱼(N.virgatus)、36尾深水金线鱼(N.bathybius)和35尾日本金线鱼(N.japonicus)性成熟后的矢耳石样本,运用几何形态测量学方法研究了4种鱼类矢耳石形态识别问题。耳石经图像处理后提取地标点坐标值,进行相对扭曲主成分分析,通过判别分析区分4种金线鱼的耳石,利用薄板样条分析和网格变形分析耳石形态变异。结果表明:在相对扭曲主成分分析中,第1、2、3主成分分别解释了总变异的30.78%、28.44%和11.75%,可以将四种金线鱼耳石区分开来。其中Ⅰ型地标点6、10、11,Ⅱ型地标点2,Ⅲ型地标点7,贡献作用较大,解释了主要形态变异。相对扭曲主成分的逐步判别分析中,四种鱼的平均判别成功率达91.3%;交互验证结果显示,四种鱼的平均判别成功率达89.8%,表明几何形态测量学分析可以作为鱼种耳石识别的有效方法之一,在耳石形态学与鱼种判别研究中具有重要应用价值。     

Unjust and unsustainable: A case study of the Açu port industrial complex

Given their potential for social and ecosystem disruption along with job creation and economic stimulus, the proliferation of extremely large-scale investment projects worldwide has created a dilemma for policymakers and public authorities. Although one method of balancing the varied interests of stakeholders is to require that development projects be sustainable, the definition of this concept has become muddled and few practical frameworks for its implementation have emerged. One strategy that does exist, however, is the just sustainability framework. The present study sought to assess the just sustainability of the Açu industrial seaport megaproject in Rio de Janeiro State, Brazil through the application of a questionnaire among 60 active marine artisan fishers of a nearby community. The results indicate that the megaproject was not sustainable. Furthermore, the results of the just sustainability indicators triangulated both with the study's primary fisher ethnographic data and with peer-reviewed scientific assessments of similar projects, thus confirming the potential value of the just sustainability framework for assessment and policy formulation.     

利用Bayes判别分析进行矢量地图修改检测

针对现有的矢量地图修改检测方法计算速度慢、效率低等问题,设计利用Bayes判别分析进行地图修改检测的方法。首先对同一幅修改前后的矢量地图分别进行栅格化,并进行配准;然后利用Bayes判别分析方法对配准后的栅格图像进行变化检测,获得矢量地图的修改区域;最后将修改区域与审校结果进行对比,发现错修改和漏修改问题。实际矢量地图数据的修改检测实验结果验证了利用Bayes判别分析方法实现地图修改检测的有效性和可行性。     

Fisher算法及加权马尔可夫链模型的耕地需求量预测方法——以山东省聊城市为例

根据聊城市1949-2007年的耕地数据,以耕地变化率来描述耕地数量变化的速率,借助Fisher最优分割法将耕地变化率状态分为5个等级,利用规范化后的各阶自相关系数为权重,运用加权马尔可夫链模型对聊城市耕地需求量进行预测。结果表明,预测值与实际值的相对误差为0.01%,预测结果非常理想,同时也验证了加权后的马尔可夫预测法更具科学性和实用性。     

基于Lg波识别判据的特性分析

Lg波是检测、识别地下核爆炸的重要震相.通常情况下,地下核爆炸的低频段Lg波能量相对较强,基于Lg波的识别判据在高频段表现较好.然而在低频范围内却表现出难以用球对称爆炸源模式解释的现象,如Lg/Pg判据在1 Hz附近失效等现象.本文利用理论地震图方法,分析了伴随层裂过程产生的重要辅助源——CLVD源对Lg波低频成分的调...     

Discriminant analysis of a Cretaceous foraminifer using shrunken estimators

Canonical variate analysis of living and fossil organisms, based on morphological characters, can sometimes greatly distort the biological interpretation (i.e., reification) of the coefficients of the eigenvectors forming the canonical variates through the inclusion of redundant within-group directions. Instability is associated with the smallest eigenvalues, particularly if these do not greatly differ from zero. In the present study of 46 borehole samples of the Late Cretaceous foraminifer Afrobolivina afraReyment, stability of the canonical variate coefficients is attained by removal of a near redundant direction of within-group variation. This leads to improved interpretability of the morphometric relationships in this species. on leave from Division of Mathematics and Statistics, CSIRO, Wembley, 6014, Western Australia.     

Detecting Holocene movements of the woodland–steppe ecotone in northern China using discriminant analysis

Discriminant functions link vegetation zones and surface pollen along the woodland–steppe ecotone in northern China. These links were utilised to reconstruct palaeovegetation using fossil pollen data from four lake sediment sites within the ecotone. Holocene movements of the vegetation zones were derived from the above results and were interpreted as the results of climatic, topographic and edaphic factors. This study shows that climatic change was the driving factor for ecotonal movement, but that the positions of vegetational zones were nevertheless controlled by topographical and edaphic conditions, and consequently boundaries between different vegetational zones responded individualistically. Copyright © 2001 John Wiley & Sons, Ltd.     

基于PCA-SVM算法对稀土元素与稀土判别指标耦合数据集的铀矿床分类

不同类型铀矿床的沥青铀矿/晶质铀矿具有不同的稀土元素组成,其组成可作为判别铀矿床类型的重要指标。采用基于Python语言的主成分分析（principal component analysis,PCA）与支持向量机（support vector machines,SVM）结合的分类模型,对收集到的全球已知6种类型铀矿床的216组沥青铀矿/晶质铀矿稀土元素数据进行研究。以216组数据为训练集,通过数据清洗、特征缩放、PCA特征提取、网格搜索和交叉验证参数寻优构建SVM分类模型,对24组同变质型胡家峪晶质铀矿进行智能识别。研究结果显示：仅使用稀土元素的14维训练集最优模型判定胡家峪晶质铀矿类型的测试准确率为0.4%;由稀土元素、稀土总量、轻重稀土比、铕异常组成的17维训练集最优模型的测试准确率为75.0%,较14维训练集提高74.6%,模型泛化能力强;而通过传统稀土元素配分曲线、w（ΣREE）-（LREE/HREE）_N图解不能有效判定胡家峪晶质铀矿类型。本次研究表明,PCA-SVM算法对增有传统稀土判别指标数据集进行挖掘可有效厘定铀氧化物成因类型,效果明显优于单纯的稀土元素数据集以及传统的稀土配分曲线、w（ΣREE）-（LREE/HREE）_N图解。     

大气电场的FFT频谱分析及雷暴预报研究

采用傅里叶变换方法将时域数据转换到频域,针对首次地闪发生(简称“雷暴天气”)和首次地闪不会发生(简称“非雷暴天气”)的大气电场强度数据做了幅度谱分析.研究发现,首次地闪前0.5h的大气电场数据与非雷暴天气中任意时段0.5h的大气电场数据的幅度谱分布具有明显差异,两类天气的幅度谱分布有一定规律可循.在此基础上对样本整理分类,将两类天气的平均幅度谱视为判别标准,利用欧氏距离判别法,对63个未知天气样本进行判别分类和效果检验,结果表明,此方法可供短时临近的首次地闪预警工作中予以参考.