0–1膨胀几何分布的客观贝叶斯分析

在医疗卫生、金融证券等应用领域，经常会同时出现零观测值、一观测值较多的情况. 为更好地拟合这类数据，提出0–1膨胀几何分布模型并进行客观贝叶斯分析. 通过参数变换，得到Jeffreys先验和reference先验. 设计后验分布的抽样算法，设置不同的样本量和参数真值，采用数值模拟方法对不同客观先验下的估计效果进行评估.     

2014“唯尔佳”优秀新产品获奖产品介绍

<正>"唯尔佳"优秀新产品的评选是由中国纺织工程学会毛纺专业委员会和《毛纺科技》杂志社联合举办的"全国毛纺年会"的一项重要内容。连续34届的"唯尔佳"优秀新产品评选活动得到了毛纺织行业的积极响应,推出了众多毛纺织新产品,引领了毛纺织产品的发展趋势,展示了企业的技术创新实力,提高了企业的产品研发实力,获得了广大毛纺织企业的认可及好评。本刊连续刊登2014"唯尔佳"优秀新产品评比部分获奖     

要闻

<正>中色股份在两国总理见证下与哈方正式签署阿克托盖铜矿硫化矿项目【本刊讯】12月14日,中哈企业家委员会第二次会议在阿斯塔纳圆满闭幕。中国有色金属建设股份有限公司(下称"中色股份")总经理王宏前、副总经理秦军满应邀出席本次闭幕式,并在中国国务院总理李克强和哈萨克斯坦总理马西莫夫的见证下,与哈萨克铜业公司签订了位于哈萨克斯坦阿克托盖地区2500万吨/年铜选厂项目的工程承包合同。     

2014“唯尔佳”优秀新产品获奖产品介绍

<正>"唯尔佳"优秀新产品的评选是由中国纺织工程学会毛纺专业委员会和《毛纺科技》杂志社联合举办的"全国毛纺年会"的一项重要内容。连续34届的"唯尔佳"优秀新产品评选活动得到了毛纺织行业的积极响应,推出了众多毛纺织新产品,引领了毛纺织产品的发展趋势,展示了企业的技术创新实力,提高了企业的产品研发实力,获得了广大毛纺织企业的认可及好评。本刊连续刊登2014"唯尔佳"优秀新产品评比部分获奖     

Analysis of the ionospheric variability based on wavelet decomposition

In this work,the ionospheric variability is analyzed by applying the wavelet decomposition technique to the noontime fo F2,F10.7,interplanetary magnetic field(IMF)Bz,Ap,and lower thermospheric temperature at pressure of 10?4 h Pa in 2002.Results show that the variance of periodic oscillations in the ionosphere is largest in the 2–4-day period and declines with the increase of the period.The maximum variance of the periodic oscillations in solar irradiation is in the 16–32-day period.For geomagnetic activities,most of the variance is about equally distributed on intervals of periods shorter than 32 days.Variance distributions of IMF Bz and lower thermospheric temperature are similar to those of the ionosphere.They show the maximum in the 2–4-day period and decline with the increase of the period.By analyzing the distributions of the variances,the potential connections between the ionosphere and the external sources are discussed.     

Effects of Cooling Rate and Component on the Microstructure and Mechanical Properties of Mg–Zn–Y Alloys

The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y(wt%) alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing(SDAS) of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates(Rc) from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0:45:45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction(Vf) of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.     

PMN-PT陶瓷中的氧缺位及其消除

研究了组成中Pb含量的变化对组成为Pbx(Mg1/3Nb2/3)0.65Ti0.35O3的铌镁酸铅-钛酸铅(PMN-PT)陶瓷压电性能的影响,发现化学计量比组成(x=1)的Pbx(Mg1/3Nb2/3)0.65Ti0.35O3陶瓷经常出现压电性能的大幅度退化现象,而A位适量缺Pb能稳定地获得高性能的Pbx(Mg1/3Nb2/3)0.65Ti0.35O3陶瓷。XPS元素价态分析的结果表明,化学计量比的Pbx(Mg1/3Nb2/3)0.65Ti0.35O3陶瓷中含有较多的氧缺位,氧缺位的产生源于MgNb2O6(MN)合成过程中的气氛差异,A位适量缺Pb能有效地消除这种氧缺位而稳定地获得正常的压电性能,其机理被认为是氧缺位与铅缺位的复合。