Singular Propositions,Negation and the Square of Opposition

This paper contains two traditions of diagrammatic studies namely one, the Euler–Venn–Peirce diagram and the other, following tradition of Aristotle, the square of oppositions. We put together both the traditions to study representations of singular propositions (through a diagram system Venn-i, involving constants), their negations and the inter relationship between the two. Along with classical negation we have incorporated negation of another kind viz. absence (taking a cue from the notion of ‘abhãva’ existing in ancient Indian knowledge system). We have also considered the changes that take place in the context of open universe.     

Quickest Paths, Straight Skeletons, and the City Voronoi Diagram

The city Voronoi diagram is induced by quickest paths in the L ₁plane, made faster by an isothetic transportation network. We investigate the rich geometric and algorithmic properties of city Voronoi diagrams, and report on their use in processing quickest-path queries. In doing so, we revisit the fact that not every Voronoi-type diagram has interpretations in both the distance model and the wavefront model. Especially, straight skeletons are a relevant example where an interpretation in the former model is lacking. We clarify the relationship between these models, and further draw a connection to the bisector-defined abstract Voronoi diagram model, with the particular goal of computing the city Voronoi diagram efficiently.     

Diagram groups are totally orderable

In this paper, we introduce the concept of the independence graph of a directed 2-complex. We show that the class of diagram groups is closed under graph products over independence graphs of rooted 2-trees. This allows us to show that a diagram group containing all countable diagram groups is a semi-direct product of a partially commutative group and R. Thompson's group F. As a result, we prove that all diagram groups are totally orderable.     

箭线网络图的唯一性特征和最优箭线图判定

提出箭线网络图由完全工序关系唯一确定、最优箭线图实工序子图唯一确定等结论和由相交紧前工序集直和分解得出的基准箭线图作最优箭线图和判定最优箭线图的概念和方法.     

The Voronoi Diagram of Curved Objects

Voronoi diagrams of curved objects can show certain phenomena that are often considered artifacts: The Voronoi diagram is not connected; there are pairs of objects whose bisector is a closed curve or even a two-dimensional object; there are Voronoi edges between different parts of the same site (so-called self-Voronoi-edges); these self-Voronoi-edges may end at seemingly arbitrary points not on a site, and, in the case of a circular site, even degenerate to a single isolated point. We give a systematic study of these phenomena, characterizing their differential-geometric and topological properties. We show how a given set of curves can be refined such that the resulting curves define a “well-behaved” Voronoi diagram. We also give a randomized incremental algorithm to compute this diagram. The expected running time of this algorithm is O(n log n).     

New Results for a Two-Loop Massless Propagator-Type Feynman Diagram

We consider a two-loop massless propagator-type Feynman diagram with an arbitrary (noninteger) index on the central line. We analytically prove the equality of two well-known results in the literature expressing this diagram in terms of hypergeometric functions 3F2 of the respective arguments ?1 and 1. We also derive new representations for this diagram, which can be important in practical calculations.     

Diagram automorphisms of quiver varieties

We show that the fixed-point subvariety of a Nakajima quiver variety under a diagram automorphism is a disconnected union of quiver varieties for the ‘split-quotient quiver’ introduced by Reiten and Riedtmann. As a special case, quiver varieties of type D arise as the connected components of fixed-point subvarieties of diagram involutions of quiver varieties of type A. In the case where the quiver varieties of type A correspond to small self-dual representations, we show that the diagram involutions coincide with classical involutions of two-row Slodowy varieties. It follows that certain quiver varieties of type D are isomorphic to Slodowy varieties for orthogonal or symplectic Lie algebras.     

Diagram groups and directed 2-complexes: Homotopy and homology

We show that diagram groups can be viewed as fundamental groups of spaces of positive paths on directed 2-complexes (these spaces of paths turn out to be classifying spaces). Thus diagram groups are analogs of second homotopy groups, although diagram groups are as a rule non-Abelian. Part of the paper is a review of the previous results from this point of view. In particular, we show that the so-called rigidity of the R. Thompson's group F and some other groups is similar to the flat torus theorem. We find several finitely presented diagram groups (even of type F_∞) each of which contains all countable diagram groups. We show how to compute minimal presentations and homology groups of a large class of diagram groups. We show that the Poincaré series of these groups are rational functions. We prove that all integer homology groups of all diagram groups are free Abelian.     

两个方程的 Wronskian 解及 Young 图证明

In this paper, we obtain the linear differential conditions of （3 ＋ 1）-dimensional Jimbo-Miwa equation and Boiti-Leon-Manna-Pempinelli equation, which guarantee that the corresponding Wronskian determinant solves the two equations in the Hirota bilinear form. By using the properties of Young diagram, we have proved the results.     

Transient Modeling and Simulation of Gas Pipe Networks with Characteristic Diagram Models for Compressors

One challenge for the simulation and optimization of real gas pipe networks is the treatment of compressors. Their behavior is usually described by characteristic diagrams reflecting the connection of the volumetric flow and the enthalpy change or shaft torque. Such models are commonly used for an optimal control of compressors and compressor stations [4,7] using stationary models for the gas flow through the pipes. For transient simulations of gas networks, simplified compressor models have been studied in [1–3]. Here, we present a transient simulation of gas pipe networks with characteristic diagram models of compressors using a stable network formulation as (partial) differential-algebraic system. (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

The Area Derivative of a Space-Filling Diagram

The motion of a biomolecule greatly depends on the engulfing solution, which is mostly water. Instead of representing individual water molecules, it is desirable to develop implicit solvent models that nevertheless accurately represent the contribution of the solvent interaction to the motion. In such models, hydrophobicity is expressed as a weighted sum of atomic surface areas. The derivatives of these weighted areas contribute to the force that drives the motion. In this paper we give formulas for the weighted and unweighted area derivatives of a molecule modeled as a space-filling diagram made up of balls in motion. Other than the radii and the centers of the balls, the formulas are given in terms of the sizes of circular arcs of the boundary and edges of the power diagram. We also give inclusion–exclusion formulas for these sizes.     

关于哈斯图的一种矩阵方法

一个集合与其上定义的偏序关系构成了一个偏序集,哈斯图简单明了的反映了一个偏序集中元素间的联系.本文从偏序关系的矩阵表示出发,给出了求哈斯图的一种方法.     

A new algorithm for dual-rate systems frequency response computation in discrete control systems

This paper addresses an easy computation of the multiple components of the response to a sinusoidal input of a dual-rate linear time-invariant discrete system from the Bode diagram of LTI systems arising from a lifted representation. Based on those results, a generalized Bode diagram is suggested. Some new conclusions derived from this conceptual interpretation are introduced. This diagram provides a better insight in the frequency-response issues in multivariable control than the standard singular value decomposition of the lifted model. As an application, the output ripple suppression in a multirate control scheme is presented.     

基于多目标影响图效果作战模型

针对目前基于效果作战评估中没有涉及多目标以及决策者的偏好的情况,将多目标影响图引入到基于效果作战模型.首先分析了基于效果作战中各主要要素之间关系,其次提出了基于效果作战模型构造过程,然后将其与多目标决策理论结合建立了多目标基于效果作战模型,用多目标影响图对其进行建模,并给出了求解方法,最后将基于多目标影响图效果作战模型应用于空战任务分配中.仿真结果表明该模型的有效性.     

网络图自动生成算法研究

本文针对当前项目管理软件中网络图绘制的缺陷 ,对网络图自动生成的算法作了新的探索 ,提出的算法力求使生成的网络图逻辑关系清楚 ,布局合理 ,直观清晰 ,对改进项目管理软件在此方面的不足甚至对整个项目管理软件的研究有重要意义 .本算法亦有一些遗留问题需进一步研究 .     

The Expected Genus of a Random Chord Diagram

To any generic curve in an oriented surface there corresponds an oriented chord diagram, and any oriented chord diagram may be realized by a curve in some oriented surface. The genus of an oriented chord diagram is the minimal genus of an oriented surface in which it may be realized. Let g _n denote the expected genus of a randomly chosen oriented chord diagram of order n. We show that g _n satisfies:

一种扩展的影响图及其求解方法

针对影响图在实际应用中的参数建模困难问题,提出了一种扩展的影响图.引入credal集作为影响图的概率参数,以表达专家的不精确和不完整信度,集成多来源的定性和定量信息.引入credal集后,影响图的推理难度进一步加大.提出了将其转化为credal网络求解的思路,并给出了一种基于路径选择的求解算法.最后用一个实例验证了算法的有效性.     

Diagram rigidity for geometric amalgamations of free groups

In this paper, we show that a class of 2-dimensional locally CAT(-1) spaces is topologically rigid: isomorphism of the fundamental groups is equivalent to the spaces being homeomorphic. An immediate application of this result is a diagram rigidity theorem for certain amalgamations of free groups. The direct limits of two such amalgamations are isomorphic if and only if there is an isomorphism between the respective diagrams.     

Empirical Negation

An extension of intuitionism to empirical discourse, a project most seriously taken up by Dummett and Tennant, requires an empirical negation whose strength lies somewhere between classical negation (‘It is unwarranted that. . . ’) and intuitionistic negation (‘It is refutable that. . . ’). I put forward one plausible candidate that compares favorably to some others that have been propounded in the literature. A tableau calculus is presented and shown to be strongly complete.