粉尘含碳球团还原方式及气氛对其还原挥发性能的影响

在1150℃和1250℃、0．1L／min和10L／min的气量下，对通人含不同CO2量的氮气影响粉尘含碳球团还原速度的实验研究表明：以滚动方式所造球团中，氧化物的还原完全以间接还原的方式进行，气氛中非还原气体流速（或流量）的增加对粉尘含碳球团氧化铁还原速度有显著的降低作用，但还原温度提高则对气量增加造成的氧化铁还原速度降低有显著的抵消作用．气氛对球团中锌的挥发速度影响很小，对铅的挥发速度几乎不产生影响．     

基于改进差别矩阵和专家知识的态势指标提取算法

针对常规粗糙集约简算法在应用中的样本指标提取困难和效率低下等问题,将粗糙集理论引入到态势指标提取中,基于差别矩阵压缩和分类选择实现态势指标决策表的信息约简,结合专家知识的指标重要性度量调整态势指标的选择,提出一种基于改进差别矩阵和专家知识的态势指标提取算法.在态势指标体系实例中进行分析和验证,实验表明该算法具有较好的态势指标约简效果,提取后的指标在网络安全评估中是合理的,因此该研究为态势指标的有效提取提供一种可行的解决途径.     

Effects of parameters on rotational fine blanking of helical gear简

The application of fine blanking to the manufacturing of helical gears directly from a strip has been restricted due to the traditional linear cutting stroke of the punch and die. In this work, rotational fine blanking which combined the linear and rotational motion of punch and counterpunch was applied for the forming of helical gears. A three-dimensional （3D） rigid-plastic finite element model was developed on the DEFORM-3D platform. By finite element simulation and analysis, the influences of key parameters on the punch load and cut surface were investigated. It is shown that： 1） with increasing the counterforce or helical angle, the punch load and the depth of die roll increase; 2） with increasing blank holder force, the punch load increases while the depth of die roll decreases; 3） V-ring indenter facilitates an improvement in the quality. The results of this research reveal the deformation mechanism of rotational fine blanking of helical gears, and provide valuable guidelines for further experimental studies.     

20CrMnTi螺旋锥齿轮中出现圆鼓泡问题的分析

在对机车转向架螺旋锥齿轮的粗、精加工中发现其表面鼓起许多小泡，将其剖开酸洗后呈现为小裂纹状，该现象在实际生产中较为罕见，对此进行分析，探讨，查找原因，确定这是钢材内气泡未能焊合的结果，为此制定了改进措施。     

焊接齿轮的制造

本文对焊接齿轮的特性,结构型式和焊缝尺寸的确定,作了简要介绍,并对不同结构焊接齿轮的制造工艺及质量进行了重点阐述。     

制镁还原罐的研制

从含镁的矿石中提炼金属镁的方法已不仅仅是电解法 ,还有目前广泛采用的真空还原法 (皮江法 ) ,但其所用的还原罐寿命短、价格高一直是困扰着国内、国外生产的难题。用研制出新的材料和改革后的铸造工艺生产出的还原罐 ,较好地解决了上述问题 ;并达到国内、国外先进水平。     

归约算法统一描述

归约算法在并行计算中应用广泛,目前有很多归约算法应用于不同的情形。这些归约算法各不相同, 逻辑拓扑是 造成区别的关键 。为了统一描述归约算法,揭示它们的共性,给出了一个逻辑拓扑的定义及其性质。在此基础上,给出了归约算法的统一描述,以利于对归约算法的理解,从而设计适应不同应用和环境的归约算法。该描述也可视为可集成不同语义的归约算法框架,从而有助于设计具有新语义的归约算法。本质上,该统一描述是一个归约算法形式定义,有助于验证归约算法的正确性。     

The Double‐Edged Sword: The Effects of Journalists' Social Media Activities on Audience Perceptions of Journalists and Their News Products

As social media become popular news platforms, journalists and news organizations have been keen to capitalize on their potential to build and maintain audiences. However, little is known about the extent to which these efforts may have adverse implications. Based on normative theories, the present study investigates the influence of journalists' social media activities (specifically, self‐disclosure and interaction with other users) on audience perceptions of journalists. An experiment (N = 267) revealed that: Although both journalists' self‐disclosure and interaction positively influenced audience perceptions of the journalists in the personal dimension, interaction negatively influenced audience perceptions in the professional dimension; and the perceptions transferred to perceptions of news products, thereby mediating the relationship between journalists' social media activities and audience news perceptions.     

基于非线性降维算法的膜蛋白类型识别

众所周知,研究未知膜蛋白的类型可对基础研究和药物发现提供有用的线索。在后基因组时代,伴随着蛋白质序列数量的剧增,用实验方法确定膜蛋白类型太过昂贵和费时。因此,研究出一种能够自动发现可能的膜蛋白的计算方法变得很重要。鉴于这种情况,曾有人采用DC(Dipeptide Composition)方法表示蛋白质序列并取得了很好的预测结果。然而,采用这种表示方法得到的特征维数很高,冗余很大,使得预测系统十分复杂。为了解决这个问题,本文采用非线性降维算法KPCA(Kernel Principle component analysis),通过从高维的DC(Dipeptide Composition)特征空间中提取出低维的重要特征来简化该系统,采用K-NN(K-nearest neighbor)分类器从约简后的低维特征中预测膜蛋白类型。实验结果表明,使用KPCA方法预测膜蛋白类型非常有效。     

From Constrained to Unconstrained Maximum Agreement Subtree in Linear Time

We propose and study the Maximum Constrained Agreement Subtree (MCAST) problem, which is a variant of the classical Maximum Agreement Subtree (MAST) problem. Our problem allows users to apply their domain knowledge to control the construction of the agreement subtrees in order to get better results. We show that the MCAST problem can be reduced to the MAST problem in linear time and thus we have algorithms for MCAST with running times matching the fastest known algorithms for MAST. A preliminary version of this paper appears in the Proceedings of the Fifth Workshop on Algorithms in Bioinformatics (WABI 2005). Research of H.F. Ting is supported in part by Hong Kong RGC Grant HKU-7172/06E.