Finite mixture of regression models for a stratified sample

Despite the popularity and importance, there is limited work on modelling data which come from complex survey design using finite mixture models. In this work, we explored the use of finite mixture regression models when the samples were drawn using a complex survey design. In particular, we considered modelling data collected based on stratified sampling design. We developed a new design-based inference where we integrated sampling weights in the complete-data log-likelihood function. The expectation–maximisation algorithm was developed accordingly. A simulation study was conducted to compare the new methodology with the usual finite mixture of a regression model. The comparison was done using bias-variance components of mean square error. Additionally, a simulation study was conducted to assess the ability of the Bayesian information criterion to select the optimal number of components under the proposed modelling approach. The methodology was implemented on real data with good results.     

城市综合体建设面临的一系列问题探讨--以南通市为例

随着房地产调控和城市化进程的加快，商业地产越来越受到开发商的青睐。城市综合体作为商业地产的典型代表以其多结构多层级的功能组合迅速提升区域价值而拥有了“城中之城”的美誉，在东部地区二三线城市大量涌现。但城市综合体带动城市发展的同时，也引发了一系列风险亟待关注。     

复亚半正定矩阵

给出了复亚半正定矩阵的概念，研究了它的基本性质及行列式理论，将Hermite阵的Schur定理，华罗庚定理，Minkowski不等式，凸性不等式，Ostrowski-Taussky不等式推广到了较广泛的复矩阵类，扩大了Minkowski不等式的指数范围，削弱了华罗庚不等式的条件。     

唐人马嵬情结的审美心理阐释

马嵬情结是指唐代诗人对马嵬事变及事变中唐玄宗与杨玉环爱情结局的一种异乎寻常的强烈而持久的关注和评判。这种关注有着深刻的社会审美心理成因。它还兆示了中晚唐世俗化的社会审美倾向的滋生、因藩镇跋扈宦官擅权而导致的皇权削弱和帝王权威在士人心目中的下降以及唐代文禁的松驰。     

试论美国电影中的英雄情结

“英雄类”影片是好莱坞制造的最具轰动效应的神话之一。本文拟对美国影片中塑造的各类英雄形象加以梳理与阐释 ,并进而对这些英雄片背后的英雄情结进行剖析 ,以期管窥美国影片中一些深层文化心理机制     

基于复杂适应系统的作战理论哲学反思

传统的作战理论与方法已经不能适应像现代信息化战争系统这类充满“活”的个体和变化因素的复杂系统，需要进行理论创新。而复杂适应系统理论是当代系统科学的一个新发展。有望成为创新作战理论的突破口。本文在分析比较作战系统的基础上，认为作战系统实质是复杂的适应系统，作战系统内的作战双方都力图以增强自身的适应性和复杂性，削弱对方的适应性和复杂性取得作战的胜利。     

无限家园--读廖志理的组诗《来自生活最初的激情》

文章通过解读组诗文本,抓住家园情结这一内核,较为翔实地剖析了诗人对农耕民族的精神历程与诗意关怀,并归纳了三个艺术特点即忧患精神的张扬、时空转换的把握和整体象征的艺术自觉.     

机械装置转子支承系统临界转速估算K3法

根据机械振动和积木式传递矩阵法的原理,提出了用于估算单、双转子系统一阶临界转速的实用方法,从而得到的“K3表”可方便地使用于产品的方案设计阶段或现场排故,并可得到满意的工程精度。     

Creating a reference to a complex emergency situation using time series methods: war in Guinea-Bissau 1998-1999

Impacts of complex emergencies or relief interventions have often been evaluated by absolute mortality compared to international standardized mortality rates. A better evaluation would be to compare with local baseline mortality of the affected populations. A projection of population-based survival data into time of emergency or intervention based on information from before the emergency may create a local baseline reference. We find a log-transformed Gaussian time series model where standard errors of the estimated rates are included in the variance to have the best forecasting capacity. However, if time-at-risk during the forecasted period is known then forecasting might be done using a Poisson time series model with overdispersion. Whatever, the standard error of the estimated rates must be included in the variance of the model either in an additive form in a Gaussian model or in a multiplicative form by overdispersion in a Poisson model. Data on which the forecasting is based must be modelled carefully concerning not only calendar-time trends but also periods with excessive frequency of events (epidemics) and seasonal variations to eliminate residual autocorrelation and to make a proper reference for comparison, reflecting changes over time during the emergency. Hence, when modelled properly it is possible to predict a reference to an emergency-affected population based on local conditions. We predicted childhood mortality during the war in Guinea-Bissau 1998-1999. We found an increased mortality in the first half-year of the war and a mortality corresponding to the expected one in the last half-year of the war.     

壳聚糖中空纤维复合膜的制备与评价

蒸汽渗透是一种新型膜分离技术。本文以脱除丙烯中微量水份为目的,对壳聚糖复合膜的制备和分离性能进行了探索。首先研制了蒸汽渗透膜,选用聚砜中空纤维支撑膜,采用涂布法制备了壳聚糖复合膜。其次,考察了制膜液浓度,交联剂用量,热处理温度,时间等因素对复合膜蒸汽渗透性能的影响。