基于SoC的嵌入式DRAM存储器内建自测试设计

内建自测试(Built-in Self Test,BIST)是测试片上系统(System on- Chip,SoC)中嵌入式存储器的重要技术;但是,利用BIST技术采用多种算法对嵌入式存储器进行测试仍面临诸多挑战;对此,提出了一种基于SoC的可以带有多种测试算法的嵌入式DRAM存储器BIST设计,所设计的测试电路可以复用状态机的状态,利用循环移位寄存器(Cyclic Shift Register,CSR)产生操作命令,利用地址产生电路产生所需地址;通过对3种BIST电路支持的算法,全速测试,面积开销3个方面的比较,表明提出的嵌入式DRAM存储器BIST设计在测试时间,测试故障覆盖率和测试面积开销等各方面都取得了较好的性能.     

机载塔康设备综合检查仪设计

使用市场上成熟的模块和技术研制机载塔康设备综合检查仪,以降低成本和提高设备的可靠性;根据设备的测试需求,选用嵌入式工业平板电脑、USB-ARINC429通讯卡、USB-数字IO卡、串行接口数字表和自研的塔康信号模拟器等构成检查仪硬件,使用CVI9.0编写了测试程序;应用表明:检查仪集成度高,使用方便,能够完成对塔康设备的自动及手动测试。     

Extreme learning machine for regression and multiclass classification

Due to the simplicity of their implementations, least square support vector machine (LS-SVM) and proximal support vector machine (PSVM) have been widely used in binary classification applications. The conventional LS-SVM and PSVM cannot be used in regression and multiclass classification applications directly, although variants of LS-SVM and PSVM have been proposed to handle such cases. This paper shows that both LS-SVM and PSVM can be simplified further and a unified learning framework of LS-SVM, PSVM, and other regularization algorithms referred to extreme learning machine (ELM) can be built. ELM works for the "generalized" single-hidden-layer feedforward networks (SLFNs), but the hidden layer (or called feature mapping) in ELM need not be tuned. Such SLFNs include but are not limited to SVM, polynomial network, and the conventional feedforward neural networks. This paper shows the following: 1) ELM provides a unified learning platform with a widespread type of feature mappings and can be applied in regression and multiclass classification applications directly; 2) from the optimization method point of view, ELM has milder optimization constraints compared to LS-SVM and PSVM; 3) in theory, compared to ELM, LS-SVM and PSVM achieve suboptimal solutions and require higher computational complexity; and 4) in theory, ELM can approximate any target continuous function and classify any disjoint regions. As verified by the simulation results, ELM tends to have better scalability and achieve similar (for regression and binary class cases) or much better (for multiclass cases) generalization performance at much faster learning speed (up to thousands times) than traditional SVM and LS-SVM.     

Enhancing collaborative filtering by user interest expansion via personalized ranking

Recommender systems suggest a few items from many possible choices to the users by understanding their past behaviors. In these systems, the user behaviors are influenced by the hidden interests of the users. Learning to leverage the information about user interests is often critical for making better recommendations. However, existing collaborative-filtering-based recommender systems are usually focused on exploiting the information about the user's interaction with the systems; the information about latent user interests is largely underexplored. To that end, inspired by the topic models, in this paper, we propose a novel collaborative-filtering-based recommender system by user interest expansion via personalized ranking, named iExpand. The goal is to build an item-oriented model-based collaborative-filtering framework. The iExpand method introduces a three-layer, user-interests-item, representation scheme, which leads to more accurate ranking recommendation results with less computation cost and helps the understanding of the interactions among users, items, and user interests. Moreover, iExpand strategically deals with many issues that exist in traditional collaborative-filtering approaches, such as the overspecialization problem and the cold-start problem. Finally, we evaluate iExpand on three benchmark data sets, and experimental results show that iExpand can lead to better ranking performance than state-of-the-art methods with a significant margin.     

Feature extraction using orthogonal discriminant local tangent space alignment

A novel algorithm called orthogonal discriminant local tangent space alignment (O-DLTSA) is proposed for supervised feature extraction. Derived from local tangent space alignment (LTSA), O-DLTSA not only inherits the advantages of LTSA which uses local tangent space as a representation of the local geometry so as to preserve the local structure, but also makes full use of class information and orthogonal subspace to improve discriminant power. The experimental results of applying O-DLTSA to standard face databases demonstrate the effectiveness of the proposed method.     

顶底板围岩不稳的缓倾斜中厚以上矿体的采矿新方案

密集平行束孔落矿的底盘漏斗采矿方案的特点是:用密集严行束孔落矿;凿岩与出矿水平合二为一;实行“掘井、劈漏、落矿三位一体”的回采工艺。该方案结构简单、采切比低、工人劳动强度低,适于开采缓倾斜顶底围岩不稳固的中厚以上矿体。     

《自动控制原理》课程中闭环脉冲传递函数算法研究

针对一般方法推导离散系统闭环脉冲传递函数过程繁琐费时的问题,给出一种先连续化求出闭环传递函数再离散化求解的简便方法,并给出使用本方法的单一化条件。对于满足该条件的系统,可直接求用简便方法求取系统的闭环脉冲传递函数,不满足该使用条件的系统,对其中间变量的求取可使用本方法,因而大大简化求解闭环脉冲传递函数的过程,为采样控制系统的分析和设计提供了很大的方便。     

Effects of plasma treatment on bioactivity of TiO2 coatings

In this work, nano-TiO₂ powders were deposited on titanium alloy substrates by atmospheric plasma spraying, followed by plasma immersion ion implantation (PIII) using hydrogen, oxygen and ammonia gases. The bioactivities of PIII-treated TiO₂ coatings were evaluated by the formation of apatite on their surface after soaked in simulated body fluids (SBF) for a period of time. As-sprayed TiO₂ coating is composed of rutile, anatase and TiO_2−x (most of them is Ti₃O₅). After immersion in SBF for two weeks, the hydrogen PIII-treated TiO₂ coating can induce bone-like apatite formation on its surface but apatite cannot be formed on the surface of as-sprayed and oxygen, ammonia PIII-treated TiO₂ coatings. The results obtained indicated that a hydrogenated surface plays a very important role to induce bioactivity of TiO₂ coatings.     

Fabrication of a novel latex-based membrane for oily wastewater filtration: effect of degassing on the properties of membrane

Iranian Polymer Journal - Nitrile butadiene rubber latex/graphene oxide (NBR/GO) membranes were fabricated by latex compounding and curing method. This was a new method to produce membrane, thus,...     

一种简单非线性PID控制在电液伺服系统中的应用研究

本文给出一种简单非线性PID控制器的设计方法。该控制器设计简单．有较好的适应性、鲁棒性和抗干扰性，通过其在电液伺服系统中的应用表明该方法的有效性和可行性，该控制方案能用于机器人等复杂的控制系统中，有较好的应用前景。