Al/Pb-WC-ZrO2复合电极材料的电化学性能研究

 研究了电镀液中固体微粒质量浓度及工艺条件对Al/Pb-WC-ZrO₂复合电极材料的表面化学组成及稳态析氧极化曲线的影响规律,对上述工艺条件进行了优化,优化后的工艺条件如下:WC:50 g/L,ZrO₂:40g/L,温度:20℃,电流密度:1.5 A/dm²,电沉积时间:2 h.所获得Al/Pb-WC-ZrO₂复合电极材料的析氧动力学参数为:a=771 mV,b=140 mV,i⁰=3.11×10^-6A·cm^-2,并且电极的析氧过电位为η=1 009 mV,复合镀层中WC和ZrO₂质量分数分别为10.02%和3.55%.     

基于无源性的定子磁场定向感应电机控制器

根据无源性控制的基本思想,并借鉴定子磁场定向控制理论,以定子磁场定向同步坐标系下的定子电流和定子磁通作为系统的状态变量,构建了一种新的电压源型混合控制器,并给出了系统的稳定条件.在理论分析的基础上,证明了在互联与阻尼分配的基于无源性的感应电机控制器设计方法中,将模型表达为欧拉方程的形式是不必要的,且动态解耦条件的数学描述约束过于严格.仿真和实验结果验证了该混合控制器的稳定性、有效性以及良好的静动态性能,同时提出的结论也由此得到了证明.     

某个非紧集上的拓扑压的变分原理

任给一个遍历测度,我们考虑在该测度下Brin-Katok定理和Birkhoff遍历定理成立的点所组成的集合.我们证明了测度理论压等于这个集合上的拓扑压.     

Neural correlation of item recognition and voice source retrieval

An experiment was conducted using event-related potentials to investigate the old/new effects of the item recognition and the voice source retrieval tasks on drawing. The results indicated that (1) the old/new effect for the voice source retrieval task was much wider than that of the item recognition task; (2) the distributive characteristics of the voice source memory effect were different from those in previous studies; (3) the old/new effects for target and non-target-old drawings were similar. These results demonstrated that the voice source retrieval task is more difficult than the item recognition task for drawing, which supports the dual-process model. The experimental material and the source characteristic regulate the spatial and temporal distributions of the old/new effect for the voice source retrieval task together.     

KDS-CM： A Cache Mechanism Based on Top-K Data Source for Deep Web Query

Caching is an important technique to enhance the efficiency of query processing. Unfortunately, traditional caching mechanisms are not efficient for deep Web because of storage space and dynamic maintenance limitations. In this paper, we present on providing a cache mechanism based on Top-K data source （KDS-CM） instead of result records for deep Web query. By integrating techniques from IR and Top-K, a data reorganization strategy is presented to model KDS-CM. Also some measures about cache management and optimization are proposed to improve the performances of cache effectively. Experimental results show the benefits of KDS-CM in execution cost and dynamic maintenance when compared with various alternate strategies.     

The orbital scale evolution of regional climate recorded in a long sediment core from Heqing, China

Based on the analysis of carbonate content and loss on ignition for a long sediment core (737 m in length) drilled in Heqing, the orbital scale evolution of the Southwest Monsoon is revealed, by using overlapped spectral analysis and filter methods. It is shown that the obliquity cycle and precession cycle are the key factors for the Southwest Monsoon evolution and that the change of the global ice volume and the uplift of the Qinghai-Tibetan Plateau also impose great influences on it.     

CD40L对B淋巴细胞表面分子及分泌IL-12的影响

在体外使用CD40L作用于B淋巴细胞使之活化,通过测定B淋巴细胞表面分子及分泌细胞因子的变化,探讨B淋巴细胞作为抗原递呈细胞在抗肿瘤免疫中的优势,为B淋巴细胞特异性活化细胞毒T淋巴细胞(cytotoxic T lymphocyte,CTL)进而发挥其肿瘤细胞杀伤效应奠定基础.取7名健康成人外周静脉血,经淋巴细胞分离液分离人外周血单个核细胞(PBMC),分为对照组和实验组,实验组培养液中加入加入CD40L和IL-4,共培养21 d.观察B淋巴细胞生长状况,并在第7 d、第14 d和第21 d,用流式细胞仪(FCAS)测定其表面分子CD80、CD86和CD19,在第21 d,使用酶联免疫吸附法(ELISA)测定培养液中的IL-12水平.结果显示,在CD40L的作用下,B淋巴细胞呈克隆样增殖,并高表达表面分子CD80/CD86和CD19,和对照组相比,B淋巴细胞分泌IL-12水平升高(P＜0.05).上述实验结果说明通过CD40L的刺激,B淋巴细胞得到了活化,提示通过该途径活化的B淋巴细胞具备了作为抗原递呈细胞而发挥其抗肿瘤免疫治疗的能力.     

Active Vibration Isolation System for Sub-microultra-precision Turning Machine

Now vibration isolation of ultra-precision machine tool is usually achieved through air-springs systems. As far as HCM-I sub-micro turning machine developed by HIT, an active vibration isolation system that consists of air-springs and electro-magnetic actuators was presented. The primary function of air-springs is to support the turning machine and to isolate the high-frequency vibration. The electro-magnetic actuators controlled by fuzzy-neural networks isolate the low-frequency vibration. The experiment indicates that active vibration isolation system isolates base-vibration effectively in all the frequency range. So the vibration of the machine bed is controlled under 10-6g and the surface roughness is improved.     

基于拍卖的多Agent协商系统的研究

在多Agent系统中经常相互协作的Agent会结成具有相对稳定的合作领域和共同的交易理念,从而形成一定的公共知识,可以协作完成子任务,而多Agent协商系统中的成员既有合作性又有自利性,只有将二者有机结合起来才能保证高效地完成任务。文章在分析拍卖方式网络化、自动化、竞争化的基础上,从拍卖请求方和能力竞争方的角度,引入拍卖过程中的超时思想和Agent合作的历史信息对拍卖任务得不到及时的处理和由于拍卖方和竞买方的信息不对称,没有考虑历史信息的情况下成交效率太低进行分析、研究,提出一种多Agent拍卖流程框架和协商算法,从而使得在拍卖中各响应者都以积极并诚实的姿态参与协商,以致大大地提高了协商效率,且增加了响应者之间的透明性。     

以“六大员”为培养目标的人才培养方案——谈建筑工程技术专业的改革与实践

本文对高职建筑工程技术专业人才培养方案提出了改革建议,思路是以"六大员"为培养目标,按"六大员"岗位要求确定人才培养方案。