鼓式制动器促动变形特性的试验研究

以制动气室推出力一行程试验数据为基础，建立了气室推杆力与行程的计算模型，根据试验数据提出了鼓式制动器的促动变形特性的计算公式，用试验方法解决了制动器推杆总行程过大的生产实际问题。研究结果表明，气室推杆总行程过大的主要影响因素为制动蹄与制动鼓之间的间隙、摩擦片的弹性模量、凸轮轴的扭转变形。     

集成分类器对脑卒中患者脑电的分类

脑卒中患者意识障碍的检查和检测耗时耗力且非连续,采集脑卒中患者的脑电信号,以研究有意识障碍与无意识障碍的脑卒中患者的自动分类。对脑卒中患者的脑电图提取多达9种定量脑电特征,构建脑网络,将这些脑网络的连通性特征输入到分类器中,实现对脑卒中患者是否有意识障碍的分类。为解决非平衡数据集分类时严重偏向多数类的问题,设计集成支持向量机分类器。实验结果显示基于现有分类器的脑卒中意识障碍的分类正确率在70%左右,敏感度在40%以下;而基于集成支持向量机分类器的分类准确性可达96.79%,同时敏感度和特异性分别为95.45%和100%。实验结果表明集成支持向量机分类器对非平衡数据集的脑电分类准确率显著提升,并促进脑卒中患者意识障碍的自动识别。     

Short Stroke Control with Gaussian Curve and PSO Algorithm in Plate Rolling Process

The precision width control is vital for product quality and production economy in plate width control process, so short stroke control method was used in plate rolling by opening or closing edger gap so as to avoid head end necking. Head end necking on different broadening ratio was analyzed, and sections of different elongations at edger roiling was calculated; based on the law of volume constancy, the adjustment functions were described by parabolic functions. Control curves were developed with three Gaussian curves by means of additional combining; SSC control curve was changed with different weights of those curves, w1 effect one-third of SSC length, w2 effect two-third of SSC length, w3 effect all three parts of SSC length. In order to adjust the amount of weights for precise quantification, PSO algorithm was used to build sufficiency function so as to obtain best rectangular degree by global optimization. Practical applications showed that the method proposed is available to improve the product rolling yields by 1.0% -2. 0% and worthy to apply to plate rolling.     

国内长冲程抽油机研究综述

长冲程抽油机具有采油效率高、冲程长、冲次低等优势,适合开采深井、稠油井、高含水井和多气井等.随着我国许多油田的开发已进入中后期,长冲程抽油机的设计和应用将进入到一个全新的阶段.在对国内长冲程抽油机进行分类的基础上,将其研究现状进行了归纳总结,分析了现有各类长冲程抽油机的工作原理、技术优势及其存在的问题.指出了抽油机技术将向无游梁、低功耗、低冲次、通用化、智能化和高适应性方向发展.     

对木棉纺织品在加工使用过程中的损耗探索

探讨木棉纤维在使用中的损耗情况。测试了木棉纤维纱和织物在加工前后的木棉棉纤维根数比、木棉混纺毛巾在使用前后的木棉与其他纤维根数比及磨损断裂特征、木棉被絮料中纤维碎屑的长度分布情况。研究结果显示：木棉纤维的磨损量明显大于棉纤维;经使用木棉纤维会产生明显折痕,其最小间距约20μm;认为木棉细胞壁上存在约20μm间隔的结构弱环,使用中木棉纤维的断裂时由局部逐步发展到整根纤维横截面分离的渐进过程,而不是一次性脆断。     

一种小型纯电动汽车充电机的设计

快速充电是当前小型电动汽车需要解决的关键技术。文中研发了一种电动汽车用智能快速充电机,该充电机采用基于微控制器MC9S12XE100控制的双闭环多模式自适应充电方式进行充电。进行了主电路参数计算,包括功率管选择以及变压器、吸收回路、滤波回路、PWM控制电路和微控制器核心电路设计等。通过试验证明,文中设计的充电机达到了性能指标要求,主回路拓扑结构及其控制电路可行。     

Reusing Service Pro cess Fragments with a Consensus Between Service Providers and Users

Recent years have witnessed a rapid growth in using Web services for data publishing and sharing among organizations. To improve the e?ciency of software development and economize on human and material resources, service reuse is viewed as a powerful means which will not only reuse atomic services, but also reuse arbitrary granularities of Service process fragments (SPFs). However, effectively reusing arbitrary granulari-ties of SPFs has not been solved yet, let alone taking di-verse QoS preferences of service providers and users into account. In this paper, we propose a novel method of SPF reuse, named SCKY, based on the Cocke-Kasami-Younger (CKY) algorithm. We first present an extended CKY to do SPF-query. Then we address how to do SPF-query by a probability CKY, i.e., return a SPF with maximum emer-gence probability. Finally, we explore the SPF-query with a consensus of QoS preferences between service providers and users. Through a set of experiments, the effectiveness and robustness of our approach are evaluated.     

不同海拔高度下破片速度衰减模型的修正方法

采用流体力学软件FLUENT研究了不同初始速度(≤2500 m·s^-1)和海拔高度(≤20 km)下破片阻力系数,对不同海拔高度下破片速度衰减模型进行修正,并开展相应的低气压破片速度衰减特性试验,验证了修正模型的准确性。结果表明:初速700 m·s^-1的球型破片和初速1000 m·s^-1的长方体破片使用修正后速度衰减模型计算结果与试验结果吻合度较高,误差均小于5%,且修正后的速度衰减模型计算精度比修正前的模型提高了10%左右。该修正后的破片速度衰减模型可用于计算阻力系数随海拔高度变化对破片速度衰减系数的影响,提高破片速度的计算精度,从而进一步提升破片战斗部威力评估的准确性。     

Chemical Conditioning as an Approach to Ischemic Stroke Tolerance: Mitochondria as the Target

It is well established that the brain can be prepared to resist or tolerate ischemic stroke injury, and mitochondrion is a major target for this tolerance. The preparation of ischemic stroke tolerance can be achieved by three major approaches: ischemic conditioning, hypoxic conditioning and chemical conditioning. In each conditioning approach, there are often two strategies that can be used to achieve the conditioning effects, namely preconditioning (Pre-C) and postconditioning (Post-C). In this review, we focus on chemical conditioning of mitochondrial proteins as targets for neuroprotection against ischemic stroke injury. Mitochondrial targets covered include complexes I, II, IV, the ATP-sensitive potassium channel (mitoKATP), adenine dinucleotide translocase (ANT) and the mitochondrial permeability transition pore (mPTP). While numerous mitochondrial proteins have not been evaluated in the context of chemical conditioning and ischemic stroke tolerance, the paradigms and approaches reviewed in this article should provide general guidelines on testing those mitochondrial components that have not been investigated. A deep understanding of mitochondria as the target of chemical conditioning for ischemic stroke tolerance should provide valuable insights into strategies for fighting ischemic stroke, a leading cause of death in the world.