6056384
Linkless symmetric drawings of series parallel digraphs
In this paper, we present a linear time algorithm for constructing linkless drawings of series parallel digraphs with maximum number of symmetries. Linkless drawing in three dimensions is a natural extension to planar drawing in two dimensions. Symmetry is one of the most important aesthetic criteria in graph drawing. More specifically, we present two algorithms: a symmetry finding algorithm which finds maximum number of three dimensional symmetries, and a drawing algorithm which constructs linkless symmetric drawings of series parallel digraphs in three dimensions.
3107205
Crossing Minimization for Symmetries
AbstractWe consider the problem of drawing a graph with a given symmetry
 such that the number of edge crossings is minimal. We show that this
 problem is NP-hard, even if the order of orbits around the rotation
 center or along the reflection axis is fixed.
 We devise an O(m log m) algorithm
 for computing a crossing minimal drawing if inter-orbit edges may
 not cross orbits, showing in particular that intra-orbit edges do
 not contribute to the NP-hardness of the crossing minimization
 problem for symmetries.
9291771
Drawing Trees Symmetrically in Three Dimensions
AbstractSymmetric graph drawing enables a clear understanding of the structure of the graph. Previous work on symmetric graph drawing has focused on two dimensions. Symmetry in three dimensions is much richer than that of two dimensions. This is the first paper to extend symmetric graph drawing into three dimensions. More specifically, the paper investigates the problem of drawing trees symmetrically in three dimensions. First, we suggest a model for drawing trees symmetrically in three dimensions. Based on this model, we present a linear time algorithm for finding the maximum number of three-dimensional symmetries in trees. We also present a three-dimensional symmetric drawing algorithm for trees.

2336438
Software reuse and competition: Consumer preferences in a software component market
Research on software reuse has traditionally focused on reuse among employees within the same organization. In contrast, our research investigates consumer preferences in a software component market with multiple producers and consumers of software components. We propose that empirically studying competition in software component markets is crucial to discovering success factors for improving software reuse. To facilitate such research, we have developed an experimental market laboratory called SofTrade; we report here the results of two empirical studies made possible by this environment. Our results support some existing reuse maxims, such as the concept that consumers prefer to reuse components that are general and flexible. Other established reuse beliefs are not supported by our results, such as the expectation that consumers will prefer objects with unique, complex features. Overall, the research reported here strongly supports the claim that the practice of exploring software reuse activity within real or artificial software component markets produces unique insights into how we can improve software reuse.
20165974
An intelligent image retrieval system using XML
With the rapid development of Internet technology, the number of Internet users and the amount of multimedia information on the Internet is ever increasing. Recently, the Web sites, such as e-business sites and shopping mall sites, deal with lots of image information. As a result, it is required to support content-based image retrieval efficiently on such image data. This paper proposes an intelligent image retrieval system, which adopts XML technology. To support object-based content retrieval on product catalog images containing multiple objects, we describe a multilevel metadata structure representing the local features, global features, and semantics of image data. To enable semantic-based and content-based retrieval on such image data, we design an XML-schema for the proposed metadata. We also describe how to automatically transform the retrieval results into the forms suitable for the various user environments, such as Web browser or mobile browser, using XSLT. The proposed scheme can be utilized to enable efficient image metadata sharing between systems, and it will contribute in improving the retrieval correctness and the user's satisfaction on content-based e-catalog image retrieval.
7349909
Reconstructing a formal security model
Abstract Role-based access control (RBAC) is a flexible approach to access control, which has generated great interest in the security community. The principal motivation behind RBAC is to simplify the complexity of administrative tasks. Several formal models of RBAC have been introduced. However, there are a few works specifying RBAC in a way which system developers or software engineers can easily understand and adopt to develop role-based systems. And there still exists a demand to have a practical representation of well-known access control models for system developers who work on secure system development. In this paper we represent a well-known RBAC model with software engineering tools such as Unified Modeling Language (UML) and Object Constraints Language (OCL) to reduce a gap between security models and system developments. The UML is a general-purpose visual modeling language in which we can specify, visualize, and document the components of a software system. And OCL is part of the UML and has been used for object-oriented analysis and design as a de facto constraints specification language in software engineering arena. Our representation is based on a standard model for RBAC proposed by the National Institute of Standards and Technology. We specify this RBAC model with UML including three views: static view, functional view, and dynamic view. We also describe how OCL can specify RBAC constraints that is one of important aspects to constrain what components in RBAC are allowed to do. In addition, we briefly discuss future directions of this work.
1395152
A Group-Theoretic Method for Drawing Graphs Symmetrically
Constructing symmetric drawings of graphs is NP-hard. In this paper, we present a new method for drawing graphs symmetrically based on group theory. More formally, we define a n-geometric automorphism group of a graph that can be displayed as symmetries of a drawing of the graph in n dimensions. Then we present an algorithm to find all 2- and 3-geometric automorphism groups of a graph. We implement the algorithm using Magma [11] and the experimental results shows that our approach is very efficient in practice. We also present a drawing algorithm to display a 2- or 3-geometric automorphism group.
653040
The Puzzle Layout Problem
This poster describes an implementation of the puzzle generators and puzzle layouts introduced in [1].