铁磁材料磁滞回线的Matlab分析方法设计

铁磁材料的磁特性常用磁滞回线来描述,而剩磁及矫顽力是铁磁材料磁滞回线上的重要参数。就如何使用M atlab来处理磁滞回线的数据给出了处理方法,并予以验证,结果表明所设计的方法处理结果精度高,拟合效果良好,并有较强的程序通用性。     

偏最小二乘判别分析结合F-score用于蛋白质组学质谱数据的特征筛选(英文)

提出了一种基于偏最小二乘判别分析和F-score的特征筛选方法,并将其用于蛋白质组学质谱数据分析。该方法主要包含3个步骤:(1)用LIMPIC算法对原始数据进行预处理;(2)计算每个变量的F-score值并将所有变量按F-score值降底的顺序排列;(3)采用偏最小二乘判别分析交互检验按前向选择法选择最佳变量子集。用本方法对一组结肠癌数据进行分析,最终从原始的16331个质荷比变量中选择了8个特征质荷比作为潜在的生物标记物。用所选择的特征对独立测试集的样本进行判别,其灵敏度和特异性分别达到了95.24%和100%。结果表明,所提出的方法可用于蛋白质组学质谱数据的特征筛选及样本分类。     

基于变量纯度的波长选择方法在近红外光谱分析中的应用

提出了一种基于光谱纯度值的变量选择方法。对光谱中各变量计算其纯度值后,按降序将相应变量排列,采用PLS交互检验按前向选择法选择最佳变量子集。用本方法对3组分混合物体系及烟草样品的近红外光谱进行变量选择,并与全谱变量建模的结果进行了比较。结果表明本实验给出的波长变量优选方法是一种比较有效和实用的变量筛选方法,通过变量筛选,可极大地减少光谱信息重叠,从而提高定量校正模型的预测精度和建模效率。     

量子纠错码[[7,1,4]]_p(p>3)存在性的图论构造方法

利用由Schingemann和Werner两人提出的构造量子纠错码的图论方法,证明了量子纠错码[[7,1,4]]p(p>3)的存在性。     

Advanced design methodology for single and dual voltage wound core power transformers based on a particular finite element model

The paper presents an accurate and cost effective three-dimensional finite element model for the analysis and design of wound core, shell type, power transformers, focusing on the short-circuit impedance evaluation. The model efficiency lies on the detailed representation of the transformer geometry along with the adoption of a particular reduced scalar potential formulation enabling three-dimensional magnetostatic problem solution without prior source field calculation. Its accuracy is validated through local field measurements and through comparison of the calculated short-circuit impedance value with the measured one for several commercial wound core, shell type transformers. In such transformers, involving extensive winding parts out of the core window, the detailed representation of the transformer geometry, including the winding cooling ducts, provides accurate results for low densities of the three-dimensional finite element mesh, resulting to reduction of the required calculation time. The model is used in the development of a computational tool, which enables the automated and accurate transformer characteristics prediction, adopted to the manufacturing process. This tool has also been applied in the impedance calculation for different winding connections of dual voltage transformers, thus providing the information needed for the achievement of an accurate design and the enhancement of the manufacturer's ability to reduce design margins. The methodology presented in this paper has been incorporated in the design process of a transformer manufacturing industry.     

盐湖卤水动态自动观测系统

介绍了盐湖卤水动态自动观测系统的体系结构，以及系统硬件、软件的设计方法和关键技术。该系统采用了主从分布式结构，是一个典型的遥控遥测系统。     

Rubidium hydrazinidoborane: Synthesis,characterization and hydrogen release properties

In this work we present rubidium hydrazinidoborane RbN₂H₃BH₃ (RbHB), the newest and last member of the alkali metal derivatives of hydrazine borane N₂H₄BH₃ (HB). It is shown that HB readily reacts with metallic rubidium in THF at room temperature to form RbHB under argon atmosphere. The molecular and crystal structures of this new compound are discussed on the basis of FTIR spectroscopy, ¹¹B MAS NMR spectroscopy, and powder X-ray diffraction analyses. RbHB crystallizes in a monoclinic P2₁ (No. 4) unit cell where each Rb⁺ cation adopts octahedral coordination surrounded by six [N₂H₃BH₃]⁻ anions, which are two more than for e.g. LiN₂H₃BH₃ (with tetrahedral coordination) in accordance with the larger size of Rb⁺. RbHB is isostructural to potassium hydrazinidoborane KN₂H₃BH₃. Its dehydrogenation properties, evaluated by using thermogravimetric analysis, differential scanning calorimetry, and isothermal analysis, are compared to those of the parent HB as well as to analogous compounds in order to evaluate the potential of RbHB as hydrogen storage material. According to the presented data, the dehydrogenation properties of RbHB are much better than those of HB and are comparable to those of the lithium derivative. Our main results are reported therein.     

Possibility neutrosophic soft sets and PNS-decision making method

In this paper, we introduce concept of possibility neutrosophic soft set and define some related concepts such as possibility neutrosophic soft subset, possibility neutrosophic soft null set, and possibility neutrosophic soft universal set. Then, based on definitions of n-norm and n-conorm, we define set theoretical operations of possibility neutrosophic soft sets such as union, intersection and complement, and investigate some properties of these operations. We also introduce AND-product and OR-product operations between two possibility neutrosophic soft sets. We propose a decision making method called possibility neutrosophic soft decision making method (PNS-decision making method) which can be applied to the decision making problems involving uncertainty based on AND-product operation. We finally give a numerical example to display application of the method that can be successfully applied to the problems.     

Failure of a pressure vessel for rail transport of fluid carbon dioxide

In 1976, a pressure vessel of a tank wagon burst during gravity shunting. The pressure vessel was filled with cold fluid carbon dioxide and failed by cleavage fracture explosively. Big parts of the vessel were flung up to 300 m, a building was destroyed, and rails as well as the superstructure of the gravity shunting yard were damaged.The initiation sites of the fracture and the orientations of crack propagation were determined by means of the patterns on the fracture surfaces of the broken parts. The initiation sites were located in the heat-affected zone (HAZ) of welds, close to transitions of cross-sections and the starting and end points, respectively, of the welds. The primary initiation of crack propagation was almost certainly on the left side, close to the weld of the fixed bearing connecting the vessel with the carriage.The results of metallographic investigations indicated the development of cold weld cracks during welding. Mechanical behavior assessments on specimens extracted from the failed vessel indicated sufficient strength and ductility in tensile loading. The values of the notched-bar impact energy or toughness were within the limits according to industry rules and standards, except for one metal sheet of the vessel that was welded to the left fixed bearing.During shunting, two tank wagons were inappropriately braked, and began to roll too quickly. One rail brake used for deceleration of the wagons caused impulsive noises and vibrations, resulting in high impulsive loading of the first wagon. The cold weld cracks in the heat-affected zones near the fixed bearing of the pressure vessel were initiation points for unstable crack growth. As the result of very low notched-bar impact toughness, crack propagation was not arrested and unstable cleavage fracture occurred.Due to a second similar accident, happened one year before, a program was started to assess characteristic values of pressure vessel materials and the influence of weld parameters by the manufacturer, the inspecting authority, and BAM. The scientific findings led to modifications of industry rules and standards with regard to using ISO-V specimens and to higher required values for notched-bar impact energy for fine grain structural steels.     

Impact of experimental warming on soil temperature and moisture of the shallow active layer of wet meadows on the Qinghai-Tibet Plateau

Climate change is now increasingly evident on the Qinghai–Tibet Plateau and has a strong impact on both the abiotic and biotic components of ecosystems, particularly on permafrost, active layer thickness, vegetation, and soil properties. Permafrost ecosystems are recognized to be sensitive to the influences of the changing climate, which may disturb the permafrost soil carbon (C) pool and lead to huge C emissions. To facilitate the assessment of warming effects on the temperature and moisture patterns in the shallow soil of the active layer of the wet meadows on the Qinghai–Tibet Plateau, near-surface air temperature was passively increased by using open-top chambers (OTCs) with two different temperature increments. Soil temperature and moisture were continuously monitored at depths of 5, 20, and 40 cm at hourly intervals in a wet meadow in the Beiluhe region on the Qinghai–Tibet Plateau from October 1, 2007 to June 24, 2009. When near-surface air temperature increased by 5.29 °C and 1.84 °C in the OTC2 and OTC1 plots, respectively, relative to the control plots, soil temperatures at depths of 5, 20, and 40 cm were seen to increase by 3.84°C, 2.23°C, and 1.42 °C, respectively, in the OTC2 plots and by 0.94°C, 0.27°C, and 0.25 °C, respectively, in the OTC1 plots. Soil moisture content at depths of 5, 20, and 40 cm declined by 8.04%, 1.79%, and 1.52%, respectively, in the OTC2 plots and by 5.33%, 0.69%, and 0.09%, respectively, in the OTC1 plots. Near-surface warming was found to extend the continuous thawing time of the shallow soil, delay the occurrence of the autumnal freezing process, and shorten the duration of continuous freezing. It was also seen to increase both the temperature of the shallow soil and the accumulated temperatures at different depths. Near-surface warming could be one of the main factors leading to the degradation of vegetation, thus threatening the stability of the soil C pool and the ecological safety of the Qinghai–Tibet Plateau.