解除方程组中四个变量为一组线性约束条件的数学处理方法

应用有限元方法求解流体力学或其他工程枝术问题,通常所得线性代数方程组的系数矩阵具有对称性。当方程组中有任意4个待定变量具有线性约束时,则可使用本文提供的数学处理方法,使原先n阶对称的系数矩阵在解除上述形式的约束条件后,方程组的阶次不变,而且系数矩阵仍具有对称性质。并且以此编制了计算机程序。     

“水利社会史”探源——兼论以水为中心的山西社会

学界通常将魏夫特的"治水社会"理论和日本学界的"水利共同体"理论作为中国水利社会史的学术源头.但事实上,水利社会史的学术源流至少可以追溯到19世纪末20世纪初的法国人文地理学,随后兴起的法国年鉴学派也受其影响颇深.这一传统持续影响到近年来由蓝克利、魏丕信等法国学者对中国山陕民间水利问题的研究.文章以山西为例,提出了水利社会史研究的内容和体系.     

当代大学生消极价值取向及其对策

当前部分大学生存在不少消极价值取向，如否定生命、铺张浪费、金钱至上、好逸恶劳、个人至上等。社会思潮的负面影响、不能理性地面对价值冲突和他们的成长环境是形成这些取向的主要原因。针对这些原因，有必要对当前的大学生进行“八荣八耻”的价值观教育、生命价值观教育，此外学会用辩证思维的方式面对多元价值冲突和进行抗挫折教育也是必要的。     

LTCC小型化Balun设计

介绍了一种基于LTCC(低温共烧陶瓷)技术的小型化balun的设计。设计的Balun采用Marchand balun结构,使用LTCC技术实现多层结构、上下耦合的方式减小balun的体积并拓展带宽。该balun工作在1.7～2.2GHz,体积为2.8mm×3mm×1mm,并且平衡端口输出具有良好的幅值平衡和180°相位差。     

基于DFT的MC-CDMA系统信道估计算法

基于导频辅助的最小平方(LS)算法是MC-CDMA中常用的信道估计算法,它运算量低,实现简单,但信道估计精度差。该文讨论了MC-CDMA的导频插入方式,提出一种基于离散傅里叶变换(DFT)的信道估计算法。该算法将LS信道估计循环前缀长度外的时域响应值置零,并设定阈值忽略循环长度内的噪声和无效径响应。该算法保留了LS算法运算量小和实现简单的优点,大大降低了噪声对信道估计精度的影响,仿真结果验证了算法的有效性。     

Bayesian inference and model comparison for asymmetric smooth transition heteroskedastic models

Inference, quantile forecasting and model comparison for an asymmetric double smooth transition heteroskedastic model is investigated. A Bayesian framework in employed and an adaptive Markov chain Monte Carlo scheme is designed. A mixture prior is proposed that alleviates the usual identifiability problem as the speed of transition parameter tends to zero, and an informative prior for this parameter is suggested, that allows for reliable inference and a proper posterior, despite the non-integrability of the likelihood function. A formal Bayesian posterior model comparison procedure is employed to compare the proposed model with its two limiting cases: the double threshold GARCH and symmetric ARX GARCH models. The proposed methods are illustrated using both simulated and international stock market return series. Some illustrations of the advantages of an adaptive sampling scheme for these models are also provided. Finally, Bayesian forecasting methods are employed in a Value-at-Risk study of the international return series. The results generally favour the proposed smooth transition model and highlight explosive and smooth nonlinear behaviour in financial markets.     

浅议海南古代的几次移民

本文阐述海南古代几次移民史实及其对海南古代经济文化发展的重要影响。     

A case-based distance method for screening in multiple-criteria decision aid

Screening is a process of multiple-criteria decision aid (MCDA) in which a large set of alternatives is reduced to a smaller set that most likely contains the best choice. We propose screening using a distance model calibrated on the basis of the decision-maker's own judgement. Viewing MCDA as preference aggregation based on consequence data, we define consequence and preference expressions (values and weights) and describe how they are aggregated. Then we define screening and explain some of its properties. Using an appropriate definition of distance, our case-based distance method screens a set of alternatives using criterion weights and a distance threshold obtained by quadratic optimization using the decision-maker's selection of alternatives from a test set. This case-based method can elicit the decision maker's preferences more expeditiously and accurately than direct inquiry. An application in water supply planning is used to demonstrate the procedure.     

企业文化构建中的"两点论"——对绍兴餐饮文化建设的反思

对企业文化建设,既要重视,又要有科学的方法.绍兴餐饮业作了有益尝试,他们在打造诚信、人本、品牌、创新四大经营理念时,从剖析餐饮业及各企业特有的经营关系,运用"两点论",把四大经营理念分别应用到对立统一的各种层面中,取得双赢效果,推动了经营矛盾的解决,拓展了四大经营理念的应用空间.文章在调查了绍兴十家中型宾馆、饭店基础上,对此进行梳理.