Approximate controllability of linear retarded systems in Hilbert spaces

The object of this paper is to construct some results on the control problems for retarded functional differential equations of parabolic type with unbounded principal operators in Hilbert spaces. In order to establish relations between controllability of the given equation and observability of the adjoint system, we investigate the equivalent relation for the completeness of generalised eigenspaces of the infinitesimal generators. Finally, when the control space is a finite-dimensional space, a necessary and sufficient condition for the approximate controllability of retarded equations is given by the so-called rank condition.     

Nonparametric testing against restricted alternatives under progessive censoring

Nonparametric testing procedures under progressive censoring schemes are often adopted in clinical trials and life testing experimentations. In a variety of situations, a null hypothesis (of the homogeneity of distributions) may be tested against a restricted viz., orthant or ordered alternative. Though such tests in a general setup have been considered in a complete sample or a single point censored (or truncated) experimental scheme, there has not been much progress with these tests in a progressively censored setup. Genuinely distribution free tests based on simple linear rank statistics and the classical union intersection principle are considered. The theory of such time sequential tests rests heavily on some basic invariance principles, and these are studied as well. The case of proportional hazard models is also treated briefly. The main emphasis is laid on the development of the relevant asymptotic theory, and in this context, some (sub) martingale characterizations of progressively censored rank statistics have been incorporated.     

DRYING OF WOOD BIOMASS AT HIGH PRESSURE STEAM ATMOSPHERE; EXPERIMENTAL RESEARCH AND APPLICATION

ABSTRACT

Imatran Voima Oy together with Technical Research Centre of Finland has carried out experimental research on fuel drying at high pressure steam atmosphere. The pilot dryer is a pressurized flash dryer. Since its commissioning in 1991, the dryer has been used for drying experiments of peat and wood biomass for about 1000 h. The dryer operates at 23 bar pressure steam atmosphere with capacity of abt. 1000 kg/h of wet feedstock.

The developed high pressure steam dryer is planned to be used in a power plant process suitable for wet fuels as peat, biomass, and brown coal. The process is based on the connection of a pressurized fuel dryer, a pressurized gasifier, and a gas turbine. The integration of the high pressure steam dryer to the process increases the power generating efficiency of the process essentially.     

基于三角模糊数截集的城市洪涝易损性联系数评价模型

为克服常用综合评价方法把评价指标样本值与评价标准等级之间的关系作为实数值之间数值接近性进行评价的结果存在系统偏差的不足，探讨了用集对分析方法进行城市洪涝易损性评价的新途径。集对分析中同、异、反关系变化是连续的，相应地，引起这种变化的联系分量系数的变化也可以看作是连续的。即由“同”、“异”变化到“反”，联系分量系数则由1、0变化到-1。对“异”联系分量系数而言，则存在最可能值0、最小值-1和最大值1，可以构造三角模糊数 。据此利用三角模糊数 的α-截集，建立了基于三角模糊数α-截集的集对分析模型。实例分析结果表明：基于三角模糊数α-截集的集对分析方法不仅可以给出评价指标的具体等级，得到的等级为一置信区间，评价结果更符合时间情况，而且还可以根据区间数的期望-方差排序法对评价结果进行综合排序，确定评价结果的优劣次序，在自然灾害系统等级评价中具有推广应用价值。     

教授分级制——路向何方

许多学校实行了教授分级制,教授分级制的初衷或许在于激励教授们勤勉于学、励志于事。但在实施过程中由于各种因素的影响,存在着不少问题。实施教授激励政策应从以下几方面进行：严把教授职称评定的关口;建立有利于教授提升的平台;隐性激励机制应规范,显性激励机制应弱化;教授的衡量与学生的评价、社会的认可结合起来。     

Multimodal biometric identification system based on finger‐veins using hybrid rank–decision‐level fusion technique

The highly random manner in which veins spread along a finger, their immunity to counterfeiting, active liveness, and user friendliness make finger veins the best choice for a biometric identification system (BIS). In this paper, veins of six fingers of two hands of a person are used to develop a secure, reliable, and robust multimodal BIS (MBIS). The main structure of the proposed MBIS is based on the effective combination of rank‐ and decision‐level fusion. In the training step, the power (weight) of each single modality is estimated by extracting the information that lies in the cumulative match characteristic (CMC) curve. The testing step consists of two main parts. In the first part, the region of the finger vein is extracted by using a simple method, and then the binarized statistical image features (BSIFs) algorithm is used to extract feature vectors. In the second part, final decision for the test input probe is made by generating ‘top rank‐decision matrix ’, which fuses the information of each biometric identifier in the hybrid rank‐decision level. The obtained results show that proposed method is more reliable and accurate than other fusion techniques at the post‐classification fusion level. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

基于对称重复纹理的摄像机位姿测量方法

某些目标上具有对称重复的纹理,这些纹理的图像矩阵具有低秩特性。当摄像机在偏离对正方向拍摄纹理时,由于存在投影形变,该纹理图像在原有方向上的对称性和重复性不再保留,从而不再具备低秩特性。通过建立摄像机拍摄方向与纹理图像的秩之间的数学模型,将摄像机方向的求解问题等效为一定约束下纹理图像的秩最小化问题。求解该问题,可得到摄像机拍摄方向,进一步结合纹理上任意两点的成像关系求解摄像机的空间位置。该方法与传统的基于目标图像中点、线等局部特征的测量方法相比,具有更高的准确性和良好的抗噪性能。仿真实验和实际实验均证明了该方法的有效性。     

低阶煤提质技术现状及发展建议

为实现低阶煤的高效利用,分析了我国低阶煤的煤质特征,阐述了国内外低阶煤压缩成型、干燥脱水和低温热解3类提质加工技术的主要特点,综述了国内外具有代表性的低阶煤提质技术的发展现状,重点介绍了国内低阶煤干燥脱水和热解提质的主要示范项目,并对我国低阶煤的利用提出建议。低阶煤热解提质后产物具有水分低,发热量高,不易自燃,便于运输和储存等特点,提高了可靠性和利用率,是未来低阶煤提质利用的重要方向。低阶煤的提质加工应充分考察我国不同地区低阶煤的煤质特征,逐步发展工艺条件温和,过程简单,适合我国低阶煤不同组成及结构特点的机械热压脱水工艺,适合与电厂集成的褐煤固体热载体法干馏技术等,同时开发多联产技术。     

构造煤微孔特征及成因探讨

基于不同变形类型和程度气煤、焦煤和无烟煤级构造煤样品的微孔（孔径<2 nm）测试结果,分析煤中微孔随煤级和变形的变化规律,探讨微孔成因。结果表明：煤中微孔孔径呈3峰分布,分别为峰1（0.457 7~0.548 0 nm）、峰2（0.548 0~0.686 3 nm）和峰3（0.785 5~0.899 0 nm）;弱和中等变形作用总体对各峰孔容和峰位影响不大,对应变形煤随煤级增高,气煤到焦煤除峰3孔容小幅增加外各峰对应孔容和峰位无明显变化,焦煤到无烟煤各峰对应孔容均显著增大,峰位则差异变化;较强和强变形作用导致峰1和峰2峰位向小孔径方向偏移,孔容除无烟煤峰2外显著提高,对峰3的影响表现在气煤和焦煤孔容小幅增加,无烟煤孔容显著减小,各煤级峰位始终固定不变;推断煤中微孔成因类型应为2种,分别对应于峰1+峰2和峰3的芳香层间孔和芳环有序堆叠形成的柱状孔。     

低中煤级煤结构演化的拉曼光谱表征

对28个最大镜质组反射率为0.30%~2.05%镜煤样品的Raman谱图进行拟合,获得拉曼结构参数。随着煤样镜质组最大反射率增大,拉曼结构参数发生有规律变化,显示出煤结构演变的复杂性。结果表明:D_1和G的位置、峰位差(G-D_1)及G的半峰宽与反射率存在良好的相关关系,D_1与G半峰宽的比值(ID_1/IG)随反射率的增大也呈现出明显的分段性。在此基础上得到煤的结构演化分为3个阶段,分别是镜质组反射率0.3%~0.8%,0.8%~1.6%和1.6%~2.0%。在镜质组反射率0.3%~0.8%阶段,D_1向低波数移动,而G向高波数移动,G的半峰宽呈现递减趋势,表明煤结构朝有序结构演化,同时,D_1的半峰宽无明显规律,ID_1/IG的变化不明显,反映芳香体系的形成比较缓慢;在镜质组反射率0.8%~1.6%阶段,煤中D_1和G的位置、峰位差和G半峰宽出现极值,响应了第2次煤化跃变;在1.6%~2.0%的阶段,各参数逐步稳定,表明煤中微晶结构基本稳定,G峰半峰宽继续减小显示芳香结构的增大过程。