一维谐振子的动量几率幅和等式型不确定关系

推出了一维谐振子的位置不确定范围、动量几率幅和动量几率密度的递推公式、动量不确定范围和等式型动量一位置不确定关系．指出一维谐振子的ΔpΔx的下限恰好是普遍形式的不确定关系给出的下限h／2，而一维无限深势阱的△p△x的下限比h／2要稍微大一些，所以，一个量子系统的ΔpΔx的下限并非必须等于h／2。     

When Good Enough Is Not Good Enough: Resolving Cataloging Issues for High Density Storage

This article identifies issues with cataloging backlogs and quality control, particularly relating to the subsequent ingest of content into library high density storage. Results of a pilot project at the University of Illinois at Urbana-Champaign are used to demonstrate the high cost of retroactively addressing cataloging concerns, and how not addressing them contributes to issues in discovery and access. Changes in local cataloging standards, and criteria for how to assess a cost/benefit ratio for quality cataloging are also discussed.     

四川石渠县藏原羚夏季数量集群及分布特点

1999年夏季(6～8月),对四川省西北部地区石渠县藏原羚种群的分布数量及集群特点进行了调查研究。主要得出如下结论:(1)它们的活动总体上是相对分散的,且分布比较均衡;(2)整个分布地区藏原羚的平均密度估计为0 117头/km2,其平均密度的无偏估计为0 0930 142头/km2,其数量估计为15112307头,平均为1901头;(3)藏原羚主要活动在海拔42004700m的范围内,特别集中在海拔4400m左右的地区;(4)藏原羚的平均集群大小±SD为4 34±4 04头,主要以小群为主,即28头的范围内(占85 11%),以2头左右居多(占31 91%)。     

电磁辐射医疗机理探讨

本工作以电磁波加热电介质理论为基础,探讨了微波的医疗机理,并简介了电磁辐射的功与过。尤其电磁波的微波波段已进入了研制理疗仪器的使用阶段,如WR—1型微波治癌仪和宽常仿生系列治疗仪等的临床应用均获显著疗效。     

钯钇氢分子结构与热力学性质

在钯Pd和钇Y原子相对论有效原子实势和基函数SDD下,使用密度泛函理论B3LYP方法计算得到钯钇氢气态分子的结构、光谱数据、能量E、熵S等性质．计算固体钯钇氢的E和S时,近似以气体分子的电子能和振动能代替固体分子的E,用电子熵和振动熵代替固体分子的S．在此近似条件下,计算了不同温度下的热力学函数及生成反应的标准焓变△H°、标准熵变△S°和标准自由能变△G°．结果表明：固体钯钇氢分子具有热力学稳定性．     

基于均匀网格的自适应密度快速聚类算法

提出了一种基于均匀网格的自适应密度快速聚类新算法．首先引入均匀网格和边界网格概念,然后给出了网格均匀度的计算方法和自适应网格划分技术．每次聚类都从均匀度最高的网格开始逐步向周围扩展均匀网格,直到遇到边界网格为止．算法除具有一般网格聚类算法的优点外,还能自适应地发现不同密度的类及其边界,能够有效地识别孤立点并具有较好的扩展性．最后,通过实验验证了该算法的有效性．     

密度泛函理论研究叠氮二氢铟多聚体的结构与性质

在DFT-B3LYP／lan12dz水平上计算研究了叠氮二氢铟多聚体（H2InN3）n（n=1～4）的结构和性质．（H2InN3）2～4多聚体的全优化几何构型均为环状构型,若单体连接方式为H2In—Nα-Nβ-Nγ,则多聚体通过一子体系叠氮基的α-N和另一子体系的In原子相连,即In—N—In结合方式．二聚体（H2InN3）2中含In2N2平面四元环结构．拥有船式和椅式两种构象的两个三聚体（H2InN3）3的结合能相近,均含In3N3六元环结构．具有In4N4八元环结构的四个四聚体的能量稍有差别．与单体相比,结构参数变化较大．同时报导了单体和多聚体在不同温度下的热力学性质,发现叠氮二氢铟体系是二聚体、三聚体和四聚体的平衡共存体．     

Numerical Simulation of Underwater Explosion Loads

Numerical simulation of TNT underwater explosion was carried out with AUTODYN software.Influences of artificial viscosity and mesh density on simulation results were discussed.Detonation waves in explosive and shock wave in water during early time of explosion are high frequency waves.Fine meshes (less than 1 mm) in explosive and water nearby,and small linear viscosity coefficients and quadratic viscosity coefficients (0.02 and 0.1 respectively,1/10 of default values) are needed in numerical simulation model.According to these rules,numerical computing pressure profiles can match well with those calculated by Zamyshlyayev empirical formula.Otherwise peak pressure would be smeared off and upstream relative errors would be cumulated downstream to make downstream peak pressure lower.     

考虑钉螺密度依赖出生率的血吸虫病模型的研究

考虑被感染的钉螺不再繁殖这一事实,建立了一个血吸虫病模型.钉螺的出生率是依赖于密度的.文章计算出基本再生数,并分析了边界平衡点的稳定性.地方病平衡点的存在性也进行了研究,其稳定性通过仿真模拟进行了证明.结果表明,地方病平衡点的数量和稳定性能通过改变与钉螺的分布面积有关的钉螺承载力来改变.     

Environmental and individual attributes associated with child maltreatment resulting in hospitalization or death

Maltreatment continues to be a leading cause of death for young children. Researchers are beginning to uncover which neighborhood attributes may be associated with maltreatment outcomes. However, few studies have been able to explore these influences while controlling for individual family attributes, and none have been able to parse out the most severe outcomes—injuries resulting in hospitalization or death. This study utilizes a retrospective, case-control design on a dataset containing both individual and environmental level attributes of children who have been hospitalized or died due to maltreatment to explore the relative influence of attributes inside and outside the household walls. Binary conditional logistic regression was used to model the outcome as a function of the individual and environmental level predictors. Separate analyses also separated the outcome by manner of maltreatment: abuse or neglect. Finally, a sub-analysis included protective predictors representing access to supportive resources. Findings indicate that neighborhood attributes were similar for both cases and controls, except in the neglect only model, wherein impoverishment was associated with higher odds of serious maltreatment. Dense housing increased risk in all models except the neglect only model. In a sub-analysis, distance to Family Resource Centers was inversely related to serious maltreatment. In all models, variables representing more extreme intervention and/or removal of the victim and/or perpetrator from the home (foster care or criminal court involvement) were negatively associated with the risk of becoming a case. Medi-Cal insurance eligibility of a child was also negatively associated with becoming a case. Government interventions may be playing a critical role in child protection. More research is needed to ascertain how these interventions assert their influence.