Linear Maps Preserving Idempotency of Products of Matrices on Upper Triangular Matrix Algebras

Let Tn be the algebra of all n × n complex upper triangular matrices. We give the concrete forms of linear injective maps on Tn which preserve the nonzero idempotency of either products of two matrices or triple Jordan products of two matrices.

Solving the generalized Sylvester matrix equation AV+BW=VF via Kronecker map

This note considers the solution to the generalized Sylvester matrix equation AV ＋ BW = VF with F being an arbitrary matrix, where V and W are the matrices to be determined. With the help of the Kronecker map, an explicit parametric solution to this matrix equation is established. The proposed solution possesses a very simple and neat form, and allows the matrix F to be undetermined.

Co-commuting Mappings of Generalized Matrix Algebras

Let G be a generalized matrix algebra over a commutative ring R and Z（G） be the center of G. Suppose that F, T ：G→G are two co-commuting R-linear mappings, i.e., F（x）x = xT（x） for all x ∈ G. In this note, we study the question of when co-commuting mappings on G are proper.

Security Implementation in WSN with Symmetric and Matrix Mapping on Asymmetric ECC Cryptographic Techniques

As the wireless sensor networks are easily deployable, the volume of sensor applications has been increased widely in various fields of military and commercial areas. In order to attain security on the data exchanged over the network, a hybrid cryptographic mechanism which includes both symmetric and asymmetric cryptographic functions is used. The public key cryptographic ECC security implementation in this paper performs a matrix mapping of data’s at the points on the elliptical curve, which are further encoded using the private symmetric cipher cryptographic algorithm. This security enhancement with the hybrid mechanism of ECC and symmetric cipher cryptographic scheme achieves efficiency in energy conservation of about 7% and 4% compared to the asymmetric and symmetric cipher security implementations in WSN.

Hot deformation and processing maps of titanium matrix composite

The hot deformation characteristics of TiC particles reinforced titanium matrix composite were studied in the temperature range from 900 ℃ to 1 150 ℃ and in the strain rate range of 10-3-10 s-1 by compression tests with Gleeble1500 simulator system. The flow behavior was described by the hyperbolic sine constitutive equation,and an average activation energy of 436.72 kJ/mol was calculated. The processing maps were calculated and analyzed according to the dynamic materials model. The maps show domains in some combinations of temperatures and strain rates and these domains are correlated with specific microstructural processes occurring during hot deformation by metallographic investigations and kinetic analysis. At the low strain rate domain occurs in the temperature range of 900-960 ℃ and strain rate range of 0.001-0.03 s-1 superplasticity and dynamic recrystallization were observed. At a high strain rate domain occurs in the temperature range of 980-1 120 ℃ and strain rate range of 0.1-10 s-1 the β phase undergoes dynamic recrystallization. Also,at a strain rate range of 0.1-10 s-1 and the temperature range of 900-930 ℃,the material exhibits flow localization.

p38 MAPK及基质金属蛋白酶在心力衰竭病人心肌重构中的意义

目的:探讨不同程度心力衰竭病人心肌组织丝裂素活化蛋白激酶(p38 MAPK)、基质金属蛋白酶家族(MMP-2、3、9)、细胞外基质(ECM)纤连蛋白(FN)表达与心肌重构的关系。方法:选择因二尖瓣关闭不全心脏病接受二尖瓣置换术的心力衰竭病人39例,正常对照8例来自意外伤亡的器官捐献者。光镜检查心肌组织病理变化;免疫沉淀法检测心肌组织p38 MAPK磷酸化,及p38 MAPK、MMP-2、3、9蛋白表达;免疫荧光法检查心肌组织FN的分布。结果:瓣膜病所致心力衰竭病人心肌组织呈典型的心肌重构病理改变。心力衰竭组心肌p38 MAPK磷酸化明显强于对照组(P<0.05),随心功能恶化,其表达逐渐增加(P<0.05或P<0.01)。心力衰竭组心肌组织MMP-2、3、9蛋白表达明显强于正常对照组,各心力衰竭组与正常对照组相比差异显著(P<0.05或P<0.01);相反,心力衰竭组心肌组织FN蛋白表达明显弱于正常组,各心力衰竭组与正常对照组相比差异显著(P<0.05或P<0.01)。结论:心力衰竭病人通过激活p38 MAPK诱导心肌细胞肥大、坏死,通过MMP-2、3、9表达量的增高降解心肌细胞外基质FN,共同参与心肌重构的病理过程而恶化心功能。

基于MAP矩阵的绿色产品设计方法探索

从绿色设计进行设计思考,以通过设计引导和促成民众的节能消费行为为核心目标,分析了绿色设计原则、设计视角与设计目标之间的整合关系,构建了针对绿色设计的MAP矩阵,并结合设计实践进行方法应用,从而探索通过MAP矩阵的绿色产品设计。

距骨骨软骨损伤MR T2-mapping与软骨基质金属蛋白酶-1表达的相关性研究

目的探讨距骨骨软骨损伤(osteochondral lesions of the talus,OLT)软骨基质金属蛋白酶-1(matrix metalloproteinase-1,MMP-1)的表达与磁共振T2值之间的关系及其在距骨骨软骨损伤的机制。材料与方法收集30例踝关节距骨骨软骨损伤行微创治疗术患者及30名健康志愿者,均行3.0 T常规踝关节磁共振成像(magnetic resonance imaging,MRI)及T2-mapping功能成像,测量距骨软骨T2值。术后离体距骨骨软骨行苏木精-伊红染色(hematoxylin-eosin staining,HE)和Western Blot法分析距骨骨软骨MMP-1的表达,统计学分析距骨骨软骨T2值与MMP-1蛋白表达的相关性。结果距骨骨软骨损伤以内中侧最为多见(磁共振6分区法),距骨骨软骨T2值随软骨损伤Mankin分级明显增大(P<0.05)。软骨MMP-1蛋白表达高级别与低级别差异明显(P<0.05)。软骨T2值与软骨MMP-1表达呈线性相关趋势,Pearson分析距骨骨软骨损伤T2值增加与MMP-1蛋白表达增加呈直线性正相关(r=0.821,P<0.0001)。结论距骨骨软骨损伤以内中侧最为多见,距骨骨软骨磁共振T2值随软骨损伤分级逐级递增;距骨骨软骨损伤磁共振T2值与MMP-1蛋白表达呈正相关,距骨骨软骨磁共振T2-mapping功能成像T2值定量分析可在体、无创性预测不同级别软骨损伤MMP-1蛋白的表达含量,为临床治疗OLT提供影像学定量依据。

用Norm Matrix实现自组织映射网络的可视化

自组织映射(SOM)算法已经被证实是一种非常有效的实现高维数据可视化的工具.但是SOM算法产生的结果——自组织映射网络必须借助于其他方法实现可视化,针对自组织映射网络的可视化方法 U-Matrix不能区分分离不明显的聚类的弊端,提出一种新的可视化方法—Norm Matrix(N-Matrix),N-Matrix计算自组织映射网络的输出神经元权向量的范数,区别空间中不同神经元的绝对距离,并结合自组织映射网络特有的保持数据之间的拓扑邻域关系的性质,实现对自组织映射网络的可视化.实验结果证明,N-Matrix不仅可以实现分离明显聚类的可视化,还可以较好的实现分离不明显的聚类的可视化.

一种基于MapReduce的知识聚类与统计机制

网络文献知识库中的海量资源及其分类的粗粒度,导致学习者容易在文献检索和阅读过程出现认知迷航和知识过载问题。该文提出一种基于Map Reduce的知识聚类与统计机制:首先,提出基于Map Reduce的共现矩阵构建算法MR-Co Matrix;其次,将共现矩阵与相似度系数结合构建相似度矩阵;然后,通过Z Scores对相似度矩阵进行标准化;最后,使用离差平方和法(Ward,s method)对相似度矩阵进行聚类,生成树状的知识聚类谱系图;基于聚类结果,提出基于Map Reduce的知识文献统计算法MR-Statistics,对每个分类的知识属性进行统计。实验结果表明:将MR-Co Matrix和MR-Statistics方法应用于网络文献知识库进行知识聚类和统计,达到较理想的聚类精度和计算效率,实现了细粒度知识聚类和多维统计,同时减少了时间开销。

DMS算法在Map/Reduce任务调度中的应用

云环境下传统的任务调度算法整体效率较低,为了提高任务调度的整体效率,在Map/Reduce基础上提出了一种基于处理时间的DMS任务调度算法。首先,对复杂任务进行预处理,将复杂任务转化为DAG图,依据任务依赖关系大小产生最佳拓扑排序,并依据排序结果将复杂任务交给work节点进行处理;其次,通过将节点处理任务的预测时间与节点处理能力的比值作为子任务在每个节点的处理"时间"进行量化建模,建立任务和处理时间的度量矩阵,依据DMS算法进行处理,从而获得任务分配最佳方案;最后,从任务调度效率与资源使用率的角度将DMS算法与公平调度算法、遗传算法行对比验证。实验结果表明,DMS算法能明显提高任务调度整体效率,充分利用各节点的计算能力提高了Map/Reduce的调度效率。

基质诱导的自体软骨移植术后3T磁共振T2mapping成像对移植软骨的分层定量评价

目的评估磁共振T2mapping成像技术在基质诱导自体软骨移植(MACT)术后的定量分析价值。方法纳入6例膝关节MACT术后患者(9处软骨损伤),分别在术后3月、6月及12月进行磁共振动态随访检查,测量软骨修复区与正常对照区深浅两个区域及全层T2值,横向比较同一时间点修复区与正常区T2值差异,纵向评估术后3、6、12个月修复区T2值的变化。结果MACT术后3、6月移植区全层T2值显著高于邻近正常软骨(P均<0.05),术后12月修复区全层T2值变化较正常对照区无明显统计学差异(P=0.063)。术后6、12个月修复区浅层软骨T2值显著高于深层(P均<0.05)。术后3、6、12个月修复区深浅层T2值纵向变化均有统计学差异(P均<0.05)。结论 MACT术后磁共振T2mapping成像可作为评估关节软骨修复效果的重要依据。

基于DMC-PID串级算法的起步离合器MAP图控制

分析了机械式自动变速器(AMT)车辆起步时离合器的接合过程。以降低起步冲击度和减小离合器滑摩功为目标,由油门开度、发动机转速、怠速目标转速以及一轴转速等参数提出了起步离合器MAP图控制策略。采用DMC-PID串级预测控制算法对离合器位置进行了动态跟踪,充分发挥了DMC算法的超前预测性、强鲁棒性以及PID控制算法的抗干扰能力。在上海华普AMT样车上进行了起步离合器道路试验,所提出的起步离合器MAP图控制策略得到了成功应用。

A self-adapting image encryption algorithm based on spatiotemporal chaos and ergodic matrix

To ensure the security of a digital image, a new self-adapting encryption algorithm based on the spatiotemporal chaos and ergodic matrix is proposed in this paper. First, the plain-image is divided into different blocks of the same size, and each block is sorted in ascending order to obtain the corresponding standard ergodic matrix. Then each block is encrypted by the spatiotemporal chaotic system and shuffled according to the standard ergodic matrix. Finally, all modules are rearranged to acquire the final encrypted image. In particular, the plain-image information is used in the initial conditions of the spatiotemporal chaos and the ergodic matrices, so different plain-images will be encrypted to obtain different cipherimages. Theoretical analysis and simulation results indicate that the performance and security of the proposed encryption scheme can encrypt the image effectively and resist various typical attacks.

ENUMERATIONS OF ONE-VERTEX MAPS WITH FACE PARTITION ON THE PLANE

In addition to the known method given in [1], authors provide other three methods to the enumeration of one-vertex maps with face partition on the plane. Correspondingly, there are four functional equations in the enufuntion. It is shown that the four equations are equivalent. Moreover, an explicit expression of the solution is found by expanding the powers of the matrix of infinite order directly. This is a new complement of what appeared in [1].

Neural network-based matrix effect correction in EDXRF analysis

In this paper we discuss neural network-based matrix effect correction in energy dispersive X-ray fluorescence (EDXRF) analysis,with detailed algorithm to classify the samples.The method can correct the matrix effect effectively through classifying the samples automatically,and influence of X-ray absorption and enhancement by major elements of the samples is reduced.Experiments for the complex matrix effect correction in EDXRF analysis of samples in Pangang showed improved accuracy of the elemental analysis result.

A Self-Adaptive Parallel Encryption Algorithm Based on Discrete 2D-Logistic Map

A self-adaptive parallel encryption algorithm based on discrete 2D-Logistic map is developed according to the position scrambling and diffusion of multi-direction in variable space of spatial chaos. The binary sequences b1b2b3···bn are obtained according to the user key, in which the binary sequence 0 and 1 denote distribution mode of processors and the number of binary sequence n denotes cycle number. Then the pseudorandom 2D matrix is generated by 2D-Logistic map, and adaptive segmentation is applied in image matrix and pseudorandom matrix according to the value and the number of binary sequence. The parallel operation is used among blocks to improve efficiency and meet real-time demand in transmission processes. However, the pixel permutation is applied in partitioned matrix through ergodic matrix generated by pseudo-random matrix-block to decrease the correlation of adjacent pixels. Then the pixel substitution is used for fully diffusing through cipher block chaining mode until n cycles. The proposed algorithm can meet the three requirements of parallel operation in image encryption and the real-time requirement in transmission processes. The security is proved by theoretical analysis and simulation results.

POSITIVE MAPS CONSTRUCTED FROM PERMUTATION PAIRS

A property(C) for permutation pairs is introduced. It is shown that if a pair{π_1, π_2} of permutations of(1,2,…,n) has property(C),then the D-type map Φ_(π_1,π_2) on n× n complex matrices constructed from {π_1,π_2} is positive. A necessary and sufficient condition is obtained for a pair {π_1,π_2} to have property(C),and an easily checked necessary and sufficient condition for the pairs of the form {π~p,π~q} to have property(C) is given, whereπ is the permutation defined by π(i) = i + 1 mod n and 1≤ p < q≤ n.

A novel interference suppression scheme applying complex weighted matrix interleaving mapping for UFMC systems

In response to the problem of inter-carrier interference(ICI)and inter-subband interference(IBI)in the received signals of universal filtered multi-carrier(UFMC)systems,a novel interfer-ence suppression design scheme applying the method of complex weighted matrix inter-leaving map-ping(CWMIM)is proposed on the basis of the existing suppression scheme of conjugate weighted butterfly interleaving mapping(CWBIM).The proposed scheme performs matrix interleaving map-ping on the transmitted signal,which not only improves the carrier interference ratio(CIR)of the received signal by combining the original IBI and ICI terms,but also further inhibits the probability of burst error in the received signal.Meanwhile,the scheme can further decrease the impact of phase rotation errors in the received signal by increasing the number of rotation factors.Theoretical analysis and simulation results demonstrate that compared with CWBIM-UFMC,the proposed CWMIM-UFMC can obtain more effective ICI and IBI suppression and better system bit error rate(BER)performance with only a little bit increase in computational complexity.

套代数上的一类非线性中心化子

为了推广算子代数中的基本理论,对一类非线性映射成为套代数上的可加中心化子的条件进行了研究。首先,基于Hilbert空间上的非平凡套定义与该套有关的套代数,并定义套代数上的一个非线性映射;其次,采用矩阵分块方法获得关于此映射的几个性质;最后,证明套代数上满足某种条件的非线性映射为可加中心化子,给出刻画该映射的具体形式。结果表明,套代数上满足某种条件的非线性映射为可加中心化子,且可完全刻画。研究结果推广了非线性映射成为套代数上可加中心化子的结论,丰富了算子代数拓扑结构的分类问题,为套代数上其他类型非线性映射问题的刻画提供了借鉴与参考。