三维激光扫描技术在引水隧洞检修中的应用

三维激光扫描技术是国际上近年发展的一项集光、电和计算机技术于一体的新技术,利用该技术可以快速、精确地获取空间数据。锦屏二级水电站引水隧洞放空检修时发现少数洞内存在混凝土破损情况,但受时间与费用等因素限制,难于以采用常规手段详细检查混凝土表面缺陷与变形等问题。通过采用三维激光扫描技术对隧洞进行全断面扫描,及时探查了混凝土表面的缺陷并进行了处理,确保了工程安全运行;同时,还得到混凝土表面的三维坐标信息,建立了混凝土表面缺陷基准数据库,可为后续进一步分析混凝土表面缺陷的变化情况提供参考。     

基于模糊物元法的黑龙江干流区生态健康评价

针对受堤防建设影响的黑龙江干流地区,基于压力-状态-响应(PSR)模型构建了流域生态健康评价体系;利用层次分析法和模糊物元理论建立了流域生态健康模糊物元评价模型,并应用到黑龙江干流行政区的生态健康评价中。结果表明,漠河县、黑河市区、同江市区和抚远县干扰前的生态健康评价值为0.679 3,0.728 3,0.731 4,0.755 8,干扰后为0.602 3,0.580 5,0.611 7,0.722 6;漠河县生态健康等级保持"亚健康",黑河市区和同江市区的生态健康等级降为"亚健康",抚远县生态健康等级保持"健康"。同时,4个评价单元对应的生态受损程度分别为11.34%,20.29%,16.37%和4.39%。此外,根据评价指标体系综合分析了4个县市存在的生态健康问题,提出了4县市生态环境保护应采取的措施。     

Redox properties of CeO2 and Pt-Rh/CeO2 studied by TAP method

Redox properties of CeO₂ and Pt-Rh/CeO₂ were studied by temporal analysis of products (TAP) method using alternative pulses of CO and O₂. A portion of pulsed CO was oxidized to CO₂ and a portion of CO was adsorbed on the surface. Pulsing ¹⁸O₂ onto the catalyst which has surface species derived from CO, evolved CO₂ contained no ¹⁸O suggesting that the surface species will be carbonate ions.     

对象代理数据库的虚属性查询优化方法磁

为对象代理数据库的虚属性查询提出两种优化方法---表达式提升和虚属性合并。表达式提升将虚属性查询转换为对源类中实属性的查询;虚属性合并是对查询涉及的属于相同源对象的多个虚属性,一次性获取相应源对象的属性值用于虚属性值的计算,避免多次访问同一源对象。通过实验分析了这两种方案对虚属性查询的性能影响,实验结果表明,对于虚属性和代理层数较多的查询,表达式提升和虚属性合并的方法极大提升了查询效率。     

统计分析及关联挖掘在大学生心理健康中的应用

为深入了解影响大学生心理健康的主要因素以及心理症状之间的关系,以某高校2011级的学生心理测试数据为基础,采用统计分析和关联规则挖掘两种方法,从性别、学生干部、独生子女、来源地、家庭结构、家庭月收入等方面进行了分析研究,根据研究结果为高校开展大学生心理健康教育的规划、决策提供依据．     

Health benefits of CLA – lessons from pig models in biomedical research

The objective of this review is to highlight the use of pig models for investigating safety, efficacy and the mechanisms of action of conjugated linoleic acid (CLA). Although CLA elicits positive effects in animal models and in vitro systems, a consistent concern in terms of translational research is that the health benefits observed by using these model systems cannot be extrapolated directly into humans. Conversely, the similarities between pigs and humans make the pig an ideal model for examining the health benefits of dietary supplements, functional foods and nutraceuticals. We have developed pig models of viral and bacterial infection to examine the preventive role of dietary CLA supplementation on virally induced immunosuppression and gut health, respectively. Results from these studies indicate that CLA significantly enhances the immune function while limiting the catabolic effects of uncontrolled immune and inflammatory responses. The scientific findings in pig models and human clinical trials demonstrate that CLA modulates immune responses in pigs and humans. Pig models of immunomodulation represent significant improvements over other animal models and in vitro systems because they mimic more closely the compartmentalization of the human immune system and the clinical presentation of human infectious, immune and inflammatory diseases.     

半监督学习在不平衡样本集分类中的应用研究

在对不平衡样本集进行分类时容易产生少数类样误差大的问题,而目前半监督学习中的算法多数是针对未有明显此类特征的数据集。针对一种半监督协同分类算法在该问题上的有效性进行了研究。由于进一步增强了分类器差异性,该算法在理论上对不平衡样本集具有良好的分类性能。根据该算法建立分类模型,利用其对桥梁结构健康数据进行分类实验,与Tri-Training算法的结果比较表明,该算法对不平衡样本集具有良好的适用性,从而验证了上述算法的有效性。     

浅论陶瓷包装的促销作用

简单的阐述了包装的含义、历史上的陶瓷包装;并从包装装潢的促销作用、引导消费过程入手,具体叙述了陶瓷包装在陶瓷销售中的促销作用。最后简述了我国与世界包装的差距,总结陶瓷包装的发展。     

Lewis acidity as an explanation for oxide promotion of metals: implications of its importance and limits for catalytic reactions

Sub-monolayer quantities of metal oxides are found to influence CO hydrogenation, CO₂ hydrogenation, acetone hydrogenation, ethylene hydroformylation, ethylene hydrogenation, and ethane hydrogenolysis over Rh foils. The metal oxides investigated include AlOx, TiOx, VOx, FeOx, ZrOx, NbOx, TaOx, and WOx. Only those reactions involving the hydrogenation of C-O bonds are enhanced by the oxide overlayers. The coverage at which maximum rate enhancement occurs is approximately 0.5 ML for each oxide promoter. Titanium, niobium, and tantalum oxides are the most effective promoters. XPS measurements after reaction show that of the oxides studied titanium, niobium, and tantalum oxide overlayers are stable in the highest oxidation states. The trend in promotion effectiveness is attributed to the direct relationship between oxidation state and Lewis acidity. For the oxide promoters, bonding at the metal oxide/metal interface between the O-end of adsorbed CO and the Lewis acidic oxide is postulated to facilitate C-O bond dissociation and subsequent hydrogenation.     

高职贫困生人格与心理健康的关系

对高职贫困生的心理健康状况与人格特征进行调查研究,为有效开展心理健康教育,提供科学依据。采用症状自评量表(SCL-90)、艾森克个性问卷(EPQ)对高职贫困生进行调查。结果表明高职贫困生SCL-90各因子分与非贫困生无显著差异,高职女生SCL-90的强迫、焦虑、抑郁、恐怖因子分高于男生,差异有统计学意义。高职贫困生的人格特征总体良好、积极。结论为要有针对性地对高职生开展心理健康教育,建立健全高职生的人格,以提高其心理健康水平。