多亚甲基多苯基多胺制造过程的优化

多亚甲基多苯基多胺是多苯基甲烷多异氰酸脂（MDI）的中间体。MDI由于其良好的性能和广泛的用途,近几年发展迅速,多亚甲基多苯基多 的制造是MDI制造过程的关键。通过对大量实验数据进行分析,根据多亚甲基多苯基多胺反应过程的反应机理,导出了产品多胺含量的影响因素,建立了多胺反应的数学模型,并应用该模型对多亚甲基多苯基多胺制造过程进行了优化。     

多层印制线路板的设计与制造

简述了多层印制线路板的优缺点,从制造工艺角度介绍了多层印制线路板的设计及注意事项。结合实际生产对多层印制线路板制造过程中的黑化和层压两道工序进行了简单介绍。     

北方粳稻籽粒多胺合成与灌浆的关系

以不同水稻品种为试材,研究了籽粒多胺含量与灌浆进程的关系,结果表明:在灌浆期 ,籽粒多胺含量依次为:腐胺穴PUT雪>亚精胺SPD>精胺SPM;随花后时间的推移,各种胺 含量逐渐减小。势粒中,SPD与PUT变化趋势大致相同,在雪灌浆期呈下降趋势;在灌浆 后期,各品种籽粒SPD和PUT含量差别不大,SPM含量下降幅度较PUT和SPD小。常规稻沈 农8714与沈农 8801在不同灌浆阶段SPD含量均高于杂交稻辽优18与辽优3225。弱势粒 中, 不同品种多胺含量在整个灌浆期间差别均较大, PUT、SPD和SPM含量降低速度均 较快, 而且峰谷出现的时间也提前。PUT含量最高时灌浆速率最大沈农8801, SPM 对 灌浆后期籽粒充实起主要作用。     

VC++环境下的多文档多窗口应用程序开发

文章直接按照MDI开发的思路介绍了如何在AppWizard生成的MDI框架中添加文档模板和ScrollView,FormView,ListView视图,并且如何处理文档模板、资源和视图之间关系的,以及在FormView加入属性页控件的具体方法.     

一种仿虎甲幼虫的多驱动器软体机器人的设计与制造

设计和制造了一种多驱动器软体机器人来模拟虎甲幼虫的爬行、转向和咬合运动．其中,软体机器人尾部采用多气囊式软体驱动器,实现了向前运动;软体机器人颈部采用纤维增强弯曲致动器,实现了转向运动;软体机器人头部采用形状记忆合金（SMA）弹簧驱动,实现了咬合运动．最后,模拟虎甲幼虫爬行捕捉小红果进行了实验,结果证明该软体机器人的多驱动器设计可以模拟虎甲幼虫进行复杂运动．     

面向多目标流水车间调度的多种群多目标遗传算法

针对制造型企业普遍存在的流水车间调度问题,建立了以最小化最迟完成时间和总延迟时间为目标的多目标调度模型,并提出一种基于分解方法的多种群多目标遗传算法进行求解.该算法将多目标流水车间调度问题分解为多个单目标子问题,并分阶段地将这些子问题引入到算法迭代过程进行求解.算法在每次迭代时,依据种群的分布情况选择各子问题的最好解及与其相似的个体分别为当前求解的子问题构造子种群,通过多种群的进化完成对多个子问题最优解的并行搜索.通过对标准测试算例进行仿真实验,结果表明所提出的算法在求解该问题上能够获得较好的非支配解集.     

NURBS曲面多分辨率光顺拼接及其在复杂产品变形设计中的应用

针对复杂产品变形设计中曲面拼接问题,提出基于小波基多尺度分解的NURBS曲面多分辨率光顺拼接与融合方法.首先根据小波分析的多分辨率理论将样条曲面分解为相互正交的两部分,其中低频粗样条函数表示光顺曲面,高频曲面细节函数表示曲面噪声部分;然后利用曲面曲率特征,在B样条小波基多水平分解过程中光顺处理曲面;最后通过设定适当的阈值过滤曲面噪声部分,重构光顺曲面.实验结果表明,文中方法既能保证拼接曲面的几何连续性,又增强了曲面外形的整体光顺性.     

基于三层集成多标记学习的蛋白质多亚细胞定位预测

针对多标记学习和集成学习在解决蛋白质多亚细胞定位预测问题上应用还不成熟的状况,研究基于集成多标记学习的蛋白质多亚细胞定位预测方法。首先,从多标记学习和集成学习相结合的角度提出了一种三层的集成多标记学习系统框架结构,该框架将学习算法和分类器进行了层次性分类,并把二分类学习、多分类学习、多标记学习和集成学习进行有效整合,形成一个通用型的三层集成多标记学习模型;其次,基于面向对象技术和统一建模语言（UML）对系统模型进行了设计,使系统具备良好的可扩展性,通过扩展手段增强系统的功能和提高系统的性能;最后,使用Java编程技术对模型进行扩展,实现了一个学习系统软件,并成功应用于蛋白质多亚细胞定位预测问题上。通过在革兰氏阳性细菌数据集上进行测试,验证了系统功能的可操作性和较好的预测性能,该系统可以作为解决蛋白质多亚细胞定位预测问题的一个有效工具。     

多胺精制系统的改进与优化

多胺精制系统的任务是脱除粗多胺中的苯胺和水,针对现有工艺存在的精制效果差、消耗高等问题,分别对影响汽提塔和干燥塔的因素进行了模拟分析,提出了相应的改进措施。改进后的流程,增加了汽提塔和干燥塔的理论板数,减少了直接蒸汽和氮气消耗;汽提塔底增设蒸发器,提高物料出口温度;利用汽提塔的直接蒸汽,增加二级蒸汽喷射系统,降低干燥塔的操作压力,减少了一个洗涤塔,提高了精制效果。改进后的工艺具有操作简化、消耗降低、质量提高等优点。     

基于蚁群Stigmergy的多智能制造主体协同感知机制研究

在对现有典型协同感知机制分析的基础上,深入探讨了多智能体制造系统的协同感知机制。首先,针对集中式和分布式两类系统群体的协商决策、协商感知的机制进行了分析;其次,着重介绍了群体智能及其机理,结合蚁群Stigmergy的作用机理进行了详细说明,并根据蚁群Stigmergy机制进行多智能制造主体的协同感知应用的研究;最后,深入研究蚁群Stigmergy协作机制,并据此建立了多智能制造主体协同感知机制过程模型。     

Zeros of f(z) = (az-b)npm (cz-d)n

The zeros off(z) = (az - b)^{n} pm (cz - d)^{n}are found to lie on a circle of radius|(ad - cb)/(|a|^{2} - |c|^{2})|with its center atz = (a^{ast}b - c^{ast}d)/(|a|^{2} - |c|^{2}), wherea, b, c, anddare complex numbers andnis assumed real. When|a| = |c|the locus of the zeros is a straight line perpendicular to the line joining the pointsb/aandb/cand intersecting it atz = 0.5(b/a + d/c). The zeros are found analytically and constructed geometrically.     

Improved construction for universality of determinant and permanent

Valiant [L. Valiant, Completeness classes in algebra, in: Proc. 11th Annual ACM Symposium on the Theory of Computing, Atlanta, GA, 1979, pp. 249–261] proved that every polynomial of formula size e is a projection of the (e+2)×(e+2) determinant polynomial. We improve “e+2” to “e+1”, also for a definition of formula size that does not count multiplications by constants as gates. Our proof imitates the “2e+2” proof of von zur Gathen [J. von zur Gathen, Feasible arithmetic computations: Valiant's hypothesis, Journal of Symbolic Computation 4 (1987) 137–172], but uses different invariants and a tighter set of base cases.     

A novel lossless data compression scheme based on the error correcting Hamming codes

This paper introduces a novel lossless binary data compression scheme that is based on the error correcting Hamming codes, namely the HCDC scheme. In this scheme, the binary sequence to be compressed is divided into blocks of n bits length. To utilize the Hamming codes, the block is considered as a Hamming codeword that consists of p parity bits and d data bits (n=d+p). Then each block is tested to find if it is a valid or a non-valid Hamming codeword. For a valid block, only the d data bits preceded by 1 are written to the compressed file, while for a non-valid block all n bits preceded by 0 are written to the compressed file. These additional 1 and 0 bits are used to distinguish the valid and the non-valid blocks during the decompression process. An analytical formula is derived for computing the compression ratio as a function of block size, and fraction of valid data blocks in the sequence. The performance of the HCDC scheme is analyzed, and the results obtained are presented in tables and graphs. Finally, conclusions and recommendations for future works are pointed out.     

Cover Image

The cover image is based on the Research Article High‐gain nonlinear observer‐based impedance control for deformable object cooperative teleoperation with nonlinear contact model by Zhenyu Lu et al., https://doi.org/10.1002/rnc.4880 .

     

Moments of conjugacy classes of binary words

For each nonempty binary word w=c₁c₂c_q, where c_i{0,1}, the nonnegative integer ∑_i=1^q (q+1−i)c_i is called the moment of w and is denoted by M(w). Let [w] denote the conjugacy class of w. Define M([w])={M(u): u[w]}, N(w)={M(u)−M(w): u[w]} and δ(w)=max{M(u)−M(v): u,v[w]}. Using these objects, we obtain equivalent conditions for a binary word to be an -word (respectively, a power of an -word). For instance, we prove that the following statements are equivalent for any binary word w with |w|2: (a) w is an -word, (b) δ(w)=|w|−1, (c) w is a cyclic balanced primitive word, (d) M([w]) is a set of |w| consecutive positive integers, (e) N(w) is a set of |w| consecutive integers and 0N(w), (f) w is primitive and [w]St.     

Squaring the circle: An algorithm for generating polyhedral invariant sets from ellipsoidal ones

This paper presents a new (geometrical) approach to the computation of polyhedral (robustly) positively invariant (PI) sets for general (possibly discontinuous) nonlinear discrete-time systems possibly affected by disturbances. Given a β-contractive ellipsoidal set , the key idea is to construct a polyhedral set that lies between the ellipsoidal sets and . A proof that the resulting polyhedral set is contractive and thus, PI, is given, and a new algorithm is developed to construct the desired polyhedral set. The problem of computing polyhedral invariant sets is formulated as a number of quadratic programming (QP) problems. The number of QP problems is guaranteed to be finite and therefore, the algorithm has finite termination. An important application of the proposed algorithm is the computation of polyhedral terminal constraint sets for model predictive control based on quadratic costs.     

The two-equal-disjoint path cover problem of Matching Composition Network

Embedding of paths have attracted much attention in the parallel processing. Many-to-many communication is one of the most central issues in various interconnection networks. A graph G is globally two-equal-disjoint path coverable if for any two distinct pairs of vertices (u,v) and (w,x) of G, there exist two disjoint paths P and Q satisfied that (1) P (Q, respectively) joins u and v (w and x, respectively), (2) |P|=|Q|, and (3) V(PQ)=V(G). The Matching Composition Network (MCN) is a family of networks which two components are connected by a perfect matching. In this paper, we consider the globally two-equal-disjoint path cover property of MCN. Applying our result, the Crossed cube CQ_n, the Twisted cube TQ_n, and the Möbius cube MQ_n can all be proven to be globally two-equal-disjoint path coverable for n5.     

Causal reasoning by evaluating the complexity of conditional densities with kernel methods

We propose a method to quantify the complexity of conditional probability measures by a Hilbert space seminorm of the logarithm of its density. The concept of reproducing kernel Hilbert spaces (RKHSs) is a flexible tool to define such a seminorm by choosing an appropriate kernel. We present several examples with artificial data sets where our kernel-based complexity measure is consistent with our intuitive understanding of complexity of densities.

The intention behind the complexity measure is to provide a new approach to inferring causal directions. The idea is that the factorization of the joint probability measure P(effect,cause) into P(effect|cause)P(cause) leads typically to “simpler” and “smoother” terms than the factorization into P(cause|effect)P(effect). Since the conventional constraint-based approach of causal discovery is not able to determine the causal direction between only two variables, our inference principle can in particular be useful when combined with other existing methods.

We provide several simple examples with real-world data where the true causal directions indeed lead to simpler (conditional) densities.     

Multimodal logic programming

We give a framework for developing the least model semantics, fixpoint semantics, and SLD-resolution calculi for logic programs in multimodal logics whose frame restrictions consist of the conditions of seriality (i.e. ) and some classical first-order Horn clauses. Our approach is direct and no special restriction on occurrences of □_i and _i is required. We apply our framework for a large class of basic serial multimodal logics, which are parameterized by an arbitrary combination of generalized versions of axioms T, B, 4, 5 (in the form, e.g. 4:□_i→□_j□_k) and I:□_i→□_j. Another part of the work is devoted to programming in multimodal logics intended for reasoning about multidegree belief, for use in distributed systems of belief, or for reasoning about epistemic states of agents in multiagent systems. For that we also use the framework, and although these latter logics belong to the mentioned class of basic serial multimodal logics, the special SLD-resolution calculi proposed for them are more efficient.     

Triple positive solutions for some second-order boundary value problem on a measure chain

In this paper, we study the existence of three positive solutions for the second-order two-point boundary value problem on a measure chain,

where f:[t₁,σ(t₂)]×[0,∞)×R→[0,∞) is continuous and p:[t₁,σ(t₂)]→[0,∞) a nonnegative function that is allowed to vanish on some subintervals of [t₁,σ(t₂)] of the measure chain. The method involves applications of a new fixed-point theorem due to Bai and Ge [Z.B. Bai, W.G. Ge, Existence of three positive solutions for some second order boundary-value problems, Comput. Math. Appl. 48 (2004) 699–707]. The emphasis is put on the nonlinear term f involved with the first order delta derivative x^Δ(t).