针对隐写分析冗余评估指标的属性约简算法

针对隐写分析评估指标体系中存在的知识冗余,提出了一种隐写分析评估指标的属性约简方法.在分析存在知识冗余的指标体系的基础上,采用BCC算法求出各评估指标初始区间及其约简,并用之将仿真实验数据离散化;之后将离散化矩阵作为HORAFA算法的输入,输出即得到最终的属性约简.仿真实验验证了该属性约简方法对冗余评估指标约简的有效性...     

单边多输出逻辑函数补集软件的设计与实现

根据单边逻辑函数的特性，介绍了一种多输入多输出单边逻辑函数补集方法，该方法采用二进制特征矩阵和状态矢量来描述原函数，进行最小列覆盖的选择形成多输出补集函数的控制矩阵，由控制矩阵与补集函数的状态矢量形成单边单输出补集合逻辑函数，通过多输出逻辑函数分解与合并最终产生多输出单边逻辑函数的补集。所设计的多输入多输出单边逻辑函数补集算法软件，在P-1．8GHz，512MBRAM的计算机上完成测试和运行。并通过测试检验程序，保证输出结果在逻辑上与输入条件求补等价。     

基于直觉模糊粒化的信息熵属性约简算法

在直觉模糊关系中,对象之间通过隶属度和非隶属度的刻画使得拥有了更为优越的关系评估效果.为了对信息系统的不确定性达到更好的度量,首先引入基于直觉模糊关系对信息系统进行直觉模糊粒化,然后在粒化的结果中依据隶属度和非隶属度分别定义了信息熵的概念,并将它们结合作为直觉模糊关系下信息系统的信息熵,最后根据该信息熵构造一种属性约简算法.实验结果表明提出的算法具有较优的属性约简性能.     

基于基因表达式程序设计的电路优化算法研究

基于Xilinx Virtex-Ⅱ系列FPGA控制逻辑块(CLB)矩阵特点以及每一个控制逻辑块能实现任何2输入1输出的逻辑功能的特点,提出了一种基于基因表达式程序设计的电路优化算法。在该算法中染色体由按线性方式连接的逻辑单元矩阵组成,采用的遗传操作包括变异和杂交,并利用真值表进行适应度评估。实验证明,所得到的电路结构优于传统方法。     

基于二元矩阵的启发式属性约简算法

本文将基于分辨矩阵的二元矩阵和基于属性重要度的启发式属性约简算法结合起来,提出了一种新颖的针对不完备信息系统的属性约简算法。该算法用条件属性和决策属性之间的依赖度来度量属性重要度,进行启发式约简。该算法将属性约简问题转化为寻找能够覆盖决策属性的二元矩阵的二元矩阵集合问题。通过实例检验,该算法是有效的。     

异或逻辑在错误检测、纠错和分析逻辑故障中的应用

异或逻辑是十分重要的复合逻辑,它在数字技术领域中应用极广,例如奇偶校验、纠错编码、计算电路及其检测系统都会用到异或逻辑。下面将通过在对数字电路有一般了解的情况下介绍一些这方面有关的例子。实现异或逻辑的电路称为异或门,它是用来判别两个输入端的逻辑状态是否相同的门电路。当两个输入端的逻辑状态不一致时,异或门有输出(输出为逻辑1),否则无输出(输出为逻辑0)。异或门的逻辑符号及真值表如图1所示。     

二进制粒属性相关判定与应用

采用二进制粒表示信息系统中的离散化属性值,即对属性进行二进制粒化,定义了基于二进制信息粒的匹配、合取及析取算子,描述了二进制粒属性相关的定义,提出了基于二进制粒的属性相关性判定矩阵的算法,算法通过判定信息系统中属性的相关性,为属性约简及关联规则的求解提供一种新方法.如果相关属性同为条件属性,则可进行约简,选择其一;如果有决策属性,则可生成强关联规则;该算法在气象数据的仿真实验中验证了其实用性.     

信息系统的规则提取研究

指出求信息系统的最简规则是一个二维极简化的问题,将行分辩且列组合具有最大强度的属性值定义为粒极值,以其逻辑关联的程度逐级进行粒运算,得最简粒(规则)解集.从理论上统一了求解信息系统的算法并用各类实例以证明.     

基于粗集可辨识矩阵的属性频率约简算法

针对信息系统在属性约简过程中存在属性频率值相同的问题进行改进.改进后的算法在基于可辨识矩阵属性频率约简算法的基础上.引进强等价集概念,以属性在可辨识矩阵中出现的次数越多其重要性越大为启发式信息,利用强等价集中的属性是可以约简的特性,在属性频率约简过程中判断具有相同属性频率属性是否最终包含在核属性集里,提出改进的属性频率约简算法.通过理论和实例的分析证明,该算法在保持时间复杂度不变的情况下,处理具有相同属性频率信息系统的属性约简,使其准确性得到提高,与原算法相比,改进后的算法可以得到一个更为精准的约简结果.     

一种基于属性值粗化的决策表正域约简算法

目前粗糙集模型属性约简大多是基于静态信息系统,而实际决策表的数据信息都是动态变化的,为了有效地对这些数据集进行处理,在信息系统属性值粗化时,首先介绍了关系矩阵增量机制,提出了一种粗糙集增量式约简的矩阵方法并构造其相应的算法,最后,通过实例分析来说明属性约简的具体操作方法和算法的有效性与可行性.     

The Models of Granular System and Algebraic Quotient Space in Granular Computing

Granular computing (GrC) is an emerging computing paradigm,and it is an umbrella term exploring multilevel granularity,we present a generic abstract mathematical model of the granular system.Supposing the inter-granule structure as an algebra,we propose the algebraic quotient space model.In this model,the granulation is based on a congruence relation and all the congruence relations on a granular system form a complete semi-order lattice,which is the theoretical basis for transformation,composition and decomposition among different granularities.The different granulation rules between the topological quotient space model and the algebraic quotient space model lead to the dissimilarity while composing granularities.A real-world case study is presented that demonstrates how the algebraic quotient space model works in the network transmission by error-correcting code.These work shows that the granular system model and the algebraic quotient space model are powerful conceptual modeling and functional specification methodologies for GrC.     

一种无线视频传输的跨层自适应不平等保护方法

无线网络的异构性给多媒体业务带来了很大的挑战,跨层设计因此成为研究的热点。该文提出一种针对视频传输的跨层自适应保护方法,根据信道变化自适应选择应用层、链路层和物理层最优的编码和传输策略组合,对视频码流中具有不同重要性的数据进行不平等保护。仿真结果证明,该文提出的跨层保护方法能够在信道条件比较差的情况下提供更好的视频传输质量。     

颗粒媒质等效电磁参数的研究

本文根据强扰动理论,导出了随机取向颗粒混合媒质等效电磁参数的计算方法。将这一理论应用于吸波材料的研究,找出了吸收剂粒子的最佳外形;获得了多粒子外形铁氧体吸波材料等效介电常数和等效磁导率的计算公式。测试数据表明,理论计算与实际测量值吻合得很好。     

YOLSO: You Only Look Small Object

Small object detection is challenging and far from satisfactory. Most general object detectors suffer from two critical issues with small objects: (1) Feature extractor based on classification network cannot express the characteristics of small objects reasonably due to insufficient appearance information of targets and a large amount of background interference around them. (2) The detector requires a much higher location accuracy for small objects than for general objects. This paper proposes an effective and efficient small object detector YOLSO to address the above problems. For feature representation, we analyze the drawbacks in previous backbones and present a Half-Space Shortcut(HSSC) module to build a background-aware backbone. Furthermore, a coarse-to-fine Feature Pyramid Enhancement(FPE) module is introduced for layer-wise aggregation at a granular level to enhance the semantic discriminability. For loss function, we propose an exponential L1 loss to promote the convergence of regression, and a focal IOU loss to focus on prime samples with high classification confidence and high IOU. Both of them significantly improves the location accuracy of small objects. The proposed YOLSO sets state-of-the-art results on two typical small object datasets, MOCOD and VeDAI, at a speed of over 200 FPS. In the meantime, it also outperforms the baseline YOLOv3 by a wide margin on the common COCO dataset.     

A Multi-Granularity Density Peak Clustering Algorithm Based on Variational Mode Decomposition

Density peak clustering (DPC) can identify cluster centers quickly,without any prior knowledge.It is supposed that the cluster centers have a high density and large distance.However,some real datasets have a hierarchical structure,which will result in local cluster centers having a high density but a smaller distance.DPC is a flat clustering algorithm that searches for cluster centers globally,without considering local differences.To address this issue,a Multi-granularity DPC (MG-DPC) algorithm based on Variational mode decomposition (VMD) is proposed.MG-DPC can find global cluster centers in the coarse-grained space,as well as local cluster centers in the fine-grained space.In addition,the density is difficult to calculate when the dataset has a high dimension.Neighborhood preserving embedding (NPE) algorithm can maintain the neighborhood relationship between samples while reducing the dimensionality.Moreover,DPC requires human experience in selecting cluster centers.This paper proposes a method for automatically selecting cluster centers based on Chebyshev's inequality.MG-DPC is implemented on the dataset of load-data to realize load classification.The clustering performance is evaluated using five validity indices compared with four typical clustering methods.The experimental results demonstrate that MG-DPC outperforms other comparison methods.     

基于粒计算的增量式知识获取方法

该文在研究粒计算理论的基础上,提出了一种基于粒计算的增量式知识获取方法。该方法通过建立决策信息系统原始的知识粒树,对新增数据,在原始知识粒树中查找相匹配的知识粒,并依据决策值更新知识粒树,实现快速高效地处理动态信息系统。算法分析及实验对比结果表明,该方法在动态信息系统知识获取方面优于RGAGC和ID4方法。     

Granular Films for Use as Thin-Film Resistors

Abstact  In this paper we discuss thin-film electrical resistors utilizing granular films of the type (Co,Ni)-(Al,Si)-O and their electrical resistive properties. Resistive properties of the granular film resistors drastically change with metal content and after annealing at 450°C. The values of temperature coefficient of resistance (TCR) in the optimum metal content of the granular films were as low as those of conventional metallic alloy film resistors. The values of sheet resistance were much higher than those of conventional metallic alloy resistors. Therefore, granular films are useful for application to thin-film resistors with the goal of miniaturizing them.     

Interfacial reaction and shear strength of SnAgCu-xNi/Ni solder joints during aging at 150 °C

The interfacial microstructure and shear strength of Sn3.8Ag0.7Cu-xNi (SAC-xNi, x = 0.5, 1, and 2) composite solders on Ni/Au finished Cu pads were investigated in detail after aging at 150 °C for up to 1000 h. The interfacial characteristics of composite solder joints were affected significantly by the weight percentages of added Ni micro-particles and aging time. After aging for 200 h, the solder joints of SAC, SAC-0.5Ni and -1Ni presented duplex intermetallic compound (IMC) layers regardless of the initial interfacial structure on as-reflowed joints, whose upper and lower IMC layers were comprised of (CuNi)₆Sn₅ and (NiCu)₃Sn₄, respectively. Only a single (NiCu)₃Sn₄ IMC layer was ever observed at the SAC-2Ni/Ni interface on whole aging process. Based on the compositional analysis, the amount of Ni within the IMC regions increased as the proportion of Ni addition increased. The IMC (NiCu)₃Sn₄ layer thickness on the interface of SAC and SAC-0.5Ni grew more slowly when compared to that of SAC-1Ni and -2Ni, while for the (CuNi)₆Sn₅ layer the reverse is true. Except the IMCs sizes are increased with increased aging time, the interfacial IMCs tended to transfer their morphologies to polyhedra. In all composite joints testing, the shear strengths were approximately equal to non-composite joints. The fracturing observed during shear testing of composite joints occurred in the bulk solder, indicating that the SAC-xNi/Ni solder joints had a desirable joint reliability.     

有机发光二极管中ADN掺杂ErQ的1.54μm电致发光

自行设计了基于8-羟基喹啉铒(ErQ)为发射层(EMLs)和二硝酰胺铵(ADN)为蓝光主体材料的近红外有机发光二级管.器件的基本结构为(p-Si/NPB/EML/Bphen/Bphen:Cs2CO3/Sm/Au),设计并比较了三套不同发射层结构(ErQ/ADN为双层结构器件,(ErQ/ADN)×3为多层结构器件,ErQ:ADN为掺杂结构器件)的器件.三组器件在一定的偏压下,均可发出1.54μm的光,对应三价铒离子4I13/2→4I15/2的跃迁.其中,ADN:ErQ(1∶1)掺杂结构的近红外电致发光强度是ADN/ErQ双层结构中的三倍.此外,不同掺杂浓度的ADN:ErQ复合膜做了以下表征:吸收谱、光致发光谱和荧光寿命谱.实验结果证实了在近红外电致发光过程中存在从ADN主体分子到ErQ发射分子的高效率的能量转移.     

BNBST无铅压电陶瓷的制备工艺研究

设计了（Bi0.55Na0.5）1-X（BaaSrb）xTiO3（BNBST[100x-100a／100b]）无铅压电陶瓷新体系。该体系压电陶瓷具有工艺特性及压电响应好，压电常数高的特点，且有实际应用前景的新型压电陶瓷材料体系。采用传统的陶瓷工艺制备了（Bi0.55Na0.5）1-X（BaaSrb）xTiO3无铅压电陶瓷，研究了制备工艺参数对其物化结构性能的影响。生料的热重-差热（TGA-DTA）分析表明，粉料合成过程中，先是SrTiO3、BaTiO3的形成，然后是（Bi0．5Na0．5）Tio，的形成，同时三者形成固溶体；密度测试表明，陶瓷的体积密度随烧结温度的升高而增大，可较易获得理论密度94％的陶瓷；X-射线能谱分析（EDAX）研究表明，陶瓷的Bi、Na的挥发随着烧结温度的升高而加剧。研究结果表明，要制备性能优良的无铅压电陶瓷，需要精确控制制备工艺。