Interactive Modeling of City Layouts using Layers of Procedural Content

In this paper, we present new solutions for the interactive modeling of city layouts that combine the power of procedural modeling with the flexibility of manual modeling. Procedural modeling enables us to quickly generate large city layouts, while manual modeling allows us to hand‐craft every aspect of a city. We introduce transformation and merging operators for both topology preserving and topology changing transformations based on graph cuts. In combination with a layering system, this allows intuitive manipulation of urban layouts using operations such as drag and drop, translation, rotation etc. In contrast to previous work, these operations always generate valid, i.e., intersection‐free layouts. Furthermore, we introduce anchored assignments to make sure that modifications are persistent even if the whole urban layout is regenerated.     

Evaluating the Impact of User Characteristics and Different Layouts on an Interactive Visualization for Decision Making

There is increasing evidence that user characteristics can have a significant impact on visualization effectiveness, suggesting that visualizations could be designed to better fit each user's specific needs. Most studies to date, however, have looked at static visualizations. Studies considering interactive visualizations have only looked at a limited number of user characteristics, and consider either low‐level tasks (e.g., value retrieval), or high‐level tasks (in particular: discovery), but not both. This paper contributes to this line of work by looking at the impact of a large set of user characteristics on user performance with interactive visualizations, for both low and high‐level tasks. We focus on interactive visualizations that support decision making, exemplified by a visualization known as Value Charts. We include in the study two versions of ValueCharts that differ in terms of layout, to ascertain whether layout mediates the impact of individual differences and could be considered as a form of personalization. Our key findings are that (i) performance with low and high‐level tasks is affected by different user characteristics, and (ii) users with low visual working memory perform better with a horizontal layout. We discuss how these findings can inform the provision of personalized support to visualization processing.     

Optimal Cache-Oblivious Mesh Layouts

A mesh is a graph that divides physical space into regularly-shaped regions. Meshes computations form the basis of many applications, including finite-element methods, image rendering, collision detection, and N-body simulations. In one important mesh primitive, called a mesh update, each mesh vertex stores a value and repeatedly updates this value based on the values stored in all neighboring vertices. The performance of a mesh update depends on the layout of the mesh in memory. Informally, if the mesh layout has good data locality (most edges connect a pair of nodes that are stored near each other in memory), then a mesh update runs quickly.     

IsoMatch: Creating Informative Grid Layouts

Collections of objects such as images are often presented visually in a grid because it is a compact representation that lends itself well for search and exploration. Most grid layouts are sorted using very basic criteria, such as date or filename. In this work we present a method to arrange collections of objects respecting an arbitrary distance measure. Pairwise distances are preserved as much as possible, while still producing the specific target arrangement which may be a 2D grid, the surface of a sphere, a hierarchy, or any other shape. We show that our method can be used for infographics, collection exploration, summarization, data visualization, and even for solving problems such as where to seat family members at a wedding. We present a fast algorithm that can work on large collections and quantitatively evaluate how well distances are preserved.     

Perfect Matching Quad Layouts for Manifold Meshes

This paper introduces a new approach to automatically generate pure quadrilateral patch layouts on manifold meshes. The algorithm is based on a careful construction of a singularity graph of a given input frame field or a given periodic global parameterization. A pure quadrilateral patch layout is then derived as a constrained minimum weight perfect matching of that graph. The resulting layout is optimal relative to a balance between coarseness and geometric feature alignment. We formulate the problem of finding pure quadrilateral patch layouts as a global optimization problem related to a well‐known concept in graph theory. The main advantage of the new method is its simplicity and its computation speed. Patch layouts generated by the present algorithm are high quality and are very competitive compared to current state of the art.     

A Comparison of User-Generated and Automatic Graph Layouts

The research presented in this paper compares user-generated and automatic graph layouts. Following the methods suggested by van Ham et al. (2008), a group of users generated graph layouts using both multi-touch interaction on a tabletop display and mouse interaction on a desktop computer. Users were asked to optimize their layout for aesthetics and analytical tasks with a social network. We discuss characteristics of the user-generated layouts and interaction methods employed by users in this process. We then report on a web-based study to compare these layouts with the output of popular automatic layout algorithms. Our results demonstrate that the best of the user-generated layouts performed as well as or better than the physics-based layout. Orthogonal and circular automatic layouts were found to be considerably less effective than either the physics-based layout or the best of the user-generated layouts. We highlight several attributes of the various layouts that led to high accuracy and improved task completion time, as well as aspects in which traditional automatic layout methods were unsuccessful for our tasks.     

基于构件的层次化可重构网络构建及重构方法

下一代网络为了保持网络发展的一致性和连贯性、融合现有底层网络通信基础设施的异构性、能够保证支撑各个领域全面信息化及保证整个网络的可管可控可信做了很多尝试.作者通过对现有网络及下一代网络发展方向的分析,提出了基于构件的层次化可重构网络体系结构及松耦合、兼容融合、扩展和隔离的构建原则.作者还提出了基于进程代数的重构原则、模型、功能实体合作方法,并提出了具体实现方案,保证了构建和重构过程中的自主性、反应性和主动性.通过搭建实验网络测试,证明了可重构网络具有良好的灵活性和扩展性.     

Graph Layouts by t‐SNE

We propose a new graph layout method based on a modification of the t‐distributed Stochastic Neighbor Embedding (t‐SNE) dimensionality reduction technique. Although t‐SNE is one of the best techniques for visualizing high‐dimensional data as 2D scatterplots, t‐SNE has not been used in the context of classical graph layout. We propose a new graph layout method, tsNET, based on representing a graph with a distance matrix, which together with a modified t‐SNE cost function results in desirable layouts. We evaluate our method by a formal comparison with state‐of‐the‐art methods, both visually and via established quality metrics on a comprehensive benchmark, containing real‐world and synthetic graphs. As evidenced by the quality metrics and visual inspection, tsNET produces excellent layouts.     

双容错数据布局构造方法研究

总结了磁盘阵列双容错编码的图表示法和双容错数据布局构造问题的研究成果,详细讨论分析了几种双容错数据布局构造方法:基于完全图的完全1-因子分解的方法、基于完全二部图的完全1-因子分解的方法和基于搜索、优化算法的方法.性能分析表明,基于完全图的完全1-因子分解的BG-HEDP布局,是一种综合性能非常好的布局.     

基于组件的反射中间件的重配置机制研究

中间件平台必须适应各种应用和嵌入式系统的日益增长的不同需求,为此,中间件平台需要具有静态配置和运行时的动态配置的能力。给出了一个面向对象的架构,使用反射的组件模型来管理配置和重配置。     

Post-Failure Reconfiguration of CSP Programs

In this paper a technique called process merging is introduced. This technique allows the merging of two communicating sequential processes into a new single process. Thus, this technique can be used to reconfigure a distributed program after a faulty processing element has been detected. The technique is most applicable to dedicated multiple microprocessor systems where the need for continuous operation is critical. A process merging algorithm which operates on distributed programs using the CSP notation is presented in detail and its operation is discussed. In order to illustrate the merging technique, the algorithm's behavior is demonstrated using two classical distributed programs: the Bounded Buffer, Producer, Consumer program and the Dining Philosophers program. Finally, the merging technique is examined with respect to its demands on overall system operation and overhead. This examinatiQn leads to suggestions for future research.     

Configuring Hierarchical Layouts to Address Research Questions

We explore the effects of selecting alternative layouts in hierarchical displays that show multiple aspects of large multivariate datasets, including spatial and temporal characteristics. Hierarchical displays of this type condition a dataset by multiple discrete variable values, creating nested graphical summaries of the resulting subsets in which size, shape and colour can be used to show subset properties. These 'small multiples' are ordered by the conditioning variable values and are laid out hierarchically using dimensional stacking. Crucially, we consider the use of different layouts at different hierarchical levels, so that the coordinates of the plane can be used more effectively to draw attention to trends and anomalies in the data. We argue that these layouts should be informed by the type of conditioning variable and by the research question being explored. We focus on space-filling rectangular layouts that provide data-dense and rich overviews of data to address research questions posed in our exploratory analysis of spatial and temporal aspects of property sales in London. We develop a notation ('HiVE') that describes visualisation and layout states and provides reconfiguration operators, demonstrate its use for reconfiguring layouts to pursue research questions and provide guidelines for this process. We demonstrate how layouts can be related through animated transitions to reduce the cognitive load associated with their reconfiguration whilst supporting the exploratory process.     

Polycube Simplification for Coarse Layouts of Surfaces and Volumes

Representing digital objects with structured meshes that embed a coarse block decomposition is a relevant problem in applications like computer animation, physically‐based simulation and Computer Aided Design (CAD). One of the key ingredients to produce coarse block structures is to achieve a good alignment between the mesh singularities (i.e., the corners of each block). In this paper we improve on the polycube‐based meshing pipeline to produce both surface and volumetric coarse block‐structured meshes of general shapes. To this aim we add a new step in the pipeline. Our goal is to optimize the positions of the polycube corners to produce as coarse as possible base complexes. We rely on re‐mapping the positions of the corners on an integer grid and then using integer numerical programming to reach the optimal. To the best of our knowledge this is the first attempt to solve the singularity misalignment problem directly in polycube space. Previous methods for polycube generation did not specifically address this issue. Our corner optimization strategy is efficient and requires a negligible extra running time for the meshing pipeline. In the paper we show that our optimized polycubes produce coarser block structured surface and volumetric meshes if compared with previous approaches. They also induce higher quality hexahedral meshes and are better suited for spline fitting because they reduce the number of splines necessary to cover the domain, thus improving both the efficiency and the overall level of smoothness throughout the volume.     

A Wirelist Compare Program for Verifying VLSI Layouts

We will describe a wirelist compare program that, together with a VLSI node extractor, is used to verify VLSI IC layout connectivity. Engineers at Digital Equipment Corporation have successfully used this tool in a production environment to debug layout errors. The program is based on a graph isomorphism algorithm and provides graphical and textual guides to pinpoint errors. We will examine this algorithm, its error outputs, and provide run-time statistics.     

自适应性重新配置模块的研究模型

从计算机网络面对的安全问题谈起,介绍了容侵系统的目标策略及可伸缩性容侵框架(SITAR)体系结构,并基于SITAR体系结构给出了自适应性重新配置模块的研究模型。     

一种低功耗可重构Cache的重构算法

随着半导体技术的发展,芯片上的功率密度也逐渐增大,这使得功耗问题在芯片设计时越来越受到人们的关注.片上Cache是处理器芯片中的主要功耗源之一,采用低功耗Cache可有效降低处理器整体功耗.对低功耗Cache设计进行了研究.介绍了当前低功耗Cache设计的主要方法和一种低功耗可重构的数据Cache的体系结构及相应的重构算法.给出了一种新的重构算法——LoW-High Boundary（LHB）算法.实验表明LHB算法在性能和功耗上均优于原算法.     

Intelligent Reconfiguration of Dynamic Distributed Components

Naming service and the reconfiguration management systems usually work in a client-server manner where both the selection of components and the reconfiguration are a result of a request. Developing intelligent systems that are capable of monitoring and learning about themselves, and thereby rapidly react to changes in their environment, has become essential to most systems. This paper proposes an extension to FRODICA (Framework for Distributed Configurable Applications), a framework that supports the development of non-functional oriented reconfiguration of distributed systems, using the Complex Organic Distributed Architecture (CODA). CODA applies cybernetic concepts such as self-organisation, self-regulation and viability to derive an intelligent architecture, which can react to failures in achieving its objectives and proactively search for successful patterns of behaviour. The result is a configuration management system, which can use the knowledge of itself to proactively and dynamically drive both the search and the reconfiguration of its components.     

基于本体影射规则的软件集成重构研究

软件重构与系统互操作是计算机科学的普遍问题,从结构化设计、面向对象方法、代理技术以及标准化与开放系统,都把软件重用或重构作为基本目标,但实现异构系统协同还需要解决语义互操作问题,大量异构的遗留软件系统（legacy系统）在语义层上的冲突阻碍着它们间的重构与互操作,该言语分析了软件代理与基本体间的关系,给出了legacy软件重构框架;引入转换规则,采用精确或近似两种方法灵活地处理多本体间的语义转换,提出了基于本体转换的异构系统语义互操作算法。