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Measuring the Size of Large NoLimit Poker Games [Download]
Title: Measuring the Size of Large NoLimit Poker Games Creator: Johanson, Michael Description: In the field of computational game theory, games are often compared in terms of their size. This can be measured in several ways, including the number of unique game states, the number of decision points, and the total number of legal actions over all decision points. These numbers are either known or estimated for a wide range of classic games such as chess and checkers. In the stochastic and imperfect information game of poker, these sizes are easily computed in "limit" games which restrict the players' available actions, but until now had only been estimated for the more complicated "nolimit" variants. In this paper, we describe a simple algorithm for quickly computing the size of twoplayer nolimit poker games, provide an implementation of this algorithm, and present for the first time precise counts of the number of game states, information sets, actions and terminal nodes in the nolimit poker games played in the Annual Computer Poker Competition. Subjects: Artificial Intelligence, poker, game theory Date Created: Feb 26, 2013 
Support for Document Entry in a Multimedia Database [Download]
Title: Support for Document Entry in a Multimedia Database Creator: ElMedani, Sherine Description: Technical report TR9623. This Technical Report describes a document entry system that supports the automatic insertion of documents with arbitrary types into a multimedia database. The documents conform to the international standards of SGML and HyTime. This is achieved by instantiating objects in the database to represent the document components. These are persistent objects that can be queried and retrieved using a query interface. To achieve this goal, the database has to be queried dynamically to retrieve metainformation about the document structure. A generic meta type system was designed to model such metainformation. This type system consists of a number of builtin types that model the characteristics common to SGML document components. Whenever support for a new class of documents is added to the system, meta types modeling the characteristics specific to this class are dynamically generated and added to the meta type system. To insert documents conforming to this class into the database, two system components were developed: the SGML Parser and the Instance Generator. The SGML Parser validates the SGML documents to ensure database consistency. The Instance Generator instantiates the appropriate database objects to represent the document. Subjects: Multimedia databases, SGML Parser, Instance Generator, document entry system, dynamic querying Date Created: 1996 
A Generic Type System for an ObjectOriented Multimedia Database System [Download]
Title: A Generic Type System for an ObjectOriented Multimedia Database System Creator: Schone, Manuela Description: Technical report TR9614. This Technical Report is based upon an M.Sc. thesis in the Department of Computing Science at the University of Alberta. It describes the design of a generic multimedia database system that supports a wide class of documents. The design is characterized by an objectoriented approach and a strict adherence to the international standards SGML and HyTime. In order to support different multimedia applications, a multimedia type system must be flexible and extensible. This is achieved by defining a number of builtin types that model primitive multimedia objects, the spatial and temporal relationships between them, and characteristics that are common to all SGML documents and their components. Whenever support for a new class of documents is added to the multimedia database system, types modeling the characteristics specific to this class of documents are dynamically created and added to the type system. These types model the components and structure of the new document class. Subjects: Database Systems Date Created: 1996 
Characterization of Solutions to block triangular Hankel Systems [Download]
Title: Characterization of Solutions to block triangular Hankel Systems Creator: Kossowski, P. Description: Technical report TR9506. A full characterization of solutions is given for a certain class of underdetermined triangular block Hankel systems of linear equations. Solutions of these systems correspond to Pade' approximants for bivariate power series with coefficients from a field. Subjects: bivariate Pade' aprroximants, block Hankel matrices Date Created: 1995 
Wellcovered graphs: some new subclasses and complexity results [Download]
Title: Wellcovered graphs: some new subclasses and complexity results Creator: Sankaranarayana, Ramesh Description: Technical report TR9402. A graph is said to be well covered if every maximal independent set has the same size, and very well covered if every maximal independent set contains exactly half the vertices in the graph. Wellcovered graphs are of interest because while the problem of finding the size of a maximum independent set is NPcomplete for graphs in general, it is in P for wellcovered graphs. Many of the existing results in this area deal with characterizations of families of wellcovered graphs. This thesis focuses on the algorithmic properties of this family. The first part of this thesis looks at the algorithmic complexities of the following problems for the families of wellcovered and very well covered graphs: chromatic number, clique cover, clique partition, dominating cycle, dominating set, Hamiltonian cycle, Hamiltonian path, independent set, independent dominating set, maximum cut, minimum fillin, recognition, Steiner tree, and vertex cover. While most of the above problems prove to be as difficult for wellcovered graphs as for graphs in general, a number of them become tractable when restricted to the family of very well covered graphs. In the second part of this thesis, an alternative characterization is given for the family of wellcovered graphs. This leads to the concept of a maximal intersection of independent sets. Based on this, a hierarchy of four new subclasses of wellcovered graphs is defined. The families are characterized and the algorithmic complexities of the above mentioned problems are studied for these families. It is also shown that the last class in the hierarchy is exactly the family of very well covered graphs without isolated vertices. A generalization of Favaron's theorem for very well covered graphs is also proved. Subjects: very well covered graphs, complexity results, Wellcovered graphs, new subclasses, characterization Date Created: 1994 
Mutable Object State for ObjectOriented Logic Programming: A Survey [Download]
Title: Mutable Object State for ObjectOriented Logic Programming: A Survey Creator: Alexiev, Vladimir Description: Technical report TR9315. One of the most difficult problems on the way to an integration of ObjectOriented and Logic Programming is the modeling of changeable object state(i.e. object dynamics) in a particular logic in order not to forfeit the declarative nature of LP. Classical logic is largely unsuitable for such a task, because it adopts a general (both temporally and spatially), Platonic notion of validity, whereas object state changes over time and is local to an object. This paper presents the problem and surveys the stateoftheart approaches to its solution, as well as some emerging, promising new approaches. The paper tries to relate the different approaches, to evaluate their merits and deficiencies and to identify promising directions for development. The emphasis in this survey is on efficient implementation of state change, one which would be suitable for the lowest fundamental level of a general OOLP language. The following approaches are covered: Assert/Retract, Declarative Database Updates and Transaction Logic, Modal and Dynamic Logics, Perpetual Objects, Logical Objects and Linear Objects, Linear Logic, Rewriting Logic and MaudeLog. Subjects: ObjectOriented Logic Programming, survey, mutable object state Date Created: 1993 
Classifying Newgroup Questions on JTree and JButton [Download]
Title: Classifying Newgroup Questions on JTree and JButton Creator: Hou, Daqing Description: Technical report TR0507. In this study, we collected and analyzed 190 and 110 questions about JTree and JButton, respectively, from the Swing forum at forum.java.sun.com. We classified these questions by the design features of these two components. This classification leads to a better understanding why certain features are particularly difficult and the identification of problems with documentation. Subjects: Jtree, Jbutton, software development Date Created: 2005 
Automatic Estimation of 3D Transformations using Skeletons for Object Alignment [Download]
Title: Automatic Estimation of 3D Transformations using Skeletons for Object Alignment Creator: Wang, Tao Description: Technical report TR0532. An algorithm for automatic estimation of 3D transformations between two objects is presented in this paper. Skeletons of the 3D objects are created with a fully parallel thinning algorithm and feature point pairs (land markers) are extracted from skeletons automatically, and least squares method is applied to solve an overdetermined linear system to estimate the 3D transformation. Experiments show that this method works quite well with high accuracy when the translations and rotation angles are small, even when there is some noise. The estimation process requires about 900 ms on an Intel Centrino Laptop with 512 MB memory, for a complex model with about 37,000 object points and 500 object points for its skeletons. Subjects: Computer Vision and Multimedia Communications Date Created: 2005 
Aggregation Convergecast Scheduling in Wireless Sensor Networks [Download]
Title: Aggregation Convergecast Scheduling in Wireless Sensor Networks Creator: Malhotra, Baljeet Description: Technical report TR0914. We consider the problem of aggregation convergecast scheduling in wireless sensor networks. Aggregation convergecast differs from regular convergecast in that it accommodates transmission dependencies that allow innetwork aggregation to be performed. We formulate the abstract problem of aggregation convergecast and review the existing literature. We observe that existing schemes adopt essentially a two phase approach, consisting of, first, a tree construction and, second, a scheduling phase. Following a similar approach, we propose two new improvements, one to each of the two phases. Starting with a new lower bound on the schedule length, we make use of it in the tree construction step. The tree construction step consists of solutions to instances of bipartite graph semimatching. The scheduling step is a weightbased priority scheme that obeys dependency (tree) and interference constraints. The combination of both improvements is demonstrated to outperform all existing solutions in the literature. We also study the impact of each of the two improvements alone and pay attention to cases where the tree construction is obviated due to the existence of extrinsic dependency constraints. Subjects: Database Systems Date Created: 2009 
Modeling Time: Back to Basics [Download]
Title: Modeling Time: Back to Basics Creator: Goralwalla, Iqbal Description: Technical report TR9603. Most of the work in modeling time in information systems has concentrated on issues such as support for historical information and providing query facilities to manipulate such information. In doing so, some simplistic view of the underling nature of time has been assumed. However, the domain of time is far from being simplistic. In this paper, we outline the various issues which arise in modeling basic temporal entities and propose solutions to these issues. More specifically, we note that the nature of temporal information can either be anchored (e.g., October 25, 1995) or unanchored (e.g., week), and is usually available in multiple granularities (e.g., the airline flight departure and arrival times are usually given in minutes, while the history of the salary of an employee is usually recorded in days). Physical temporal information also needs to be represented in a manner so as to be human readable. This is achieved using calenders. In this work, we show how both anchored and unanchored temporal entities are represented within the context of calenders. We discuss how calenders provide relationships between multiple granularities and facilitate the conversion of anchored and unanchored times from one granularity to another. We also give the semantics of various operations on anchored and unanchored times. Subjects: temporal databases, granularity, calenders, object models Date Created: 1996