18193868
Interval Queries on Object Histories: Extended Abstract
This extended abstract introduces the notion of ’ interval queries ’ on historical data for objects (here, called ‘object histories’) and explores a certain closure property. As for describing historical data for objects, we use our mathematical model introduced in our earlier paper. The major construct in the model is a ‘computation-tuple sequence scheme’ (abbreviated CSS), which specifies the set of all possible ‘valid’ object histories for the same type of object. Interval queries are those queries which return an interval (history) from a given object history. We provide conditions under which an interval query applied to object histories described by one CSS yields, as its answers. the set of all object histories which can be described by another CSS.
26205197
Behavior Analysis of Object-Oriented Databases: Method Structure, Execution Trees, and Reachability (Extended Abstract)
A theoretical model for analyzing the behavior of method execution in object-oriented databases (OODBs) is introduced and used to study issues of reachability, nontermination, and well-typedness in the context of restricted classes of OODBs.
32965529
Interval Queries on Object Histories
Abstract The present paper introduces the notion of “interval queries” on object histories and explores a certain closure property. In particular, conditions are provided under which an interval query applied to object histories described by one “computational-tuple sequence scheme” (CSS) yields, as its answer, the set of all object histories which can be described by another CSS.
34835412
A Relational Data Language with Simplified Binary Relation Handling Capability
In order to develop a general purpose research information system, we have introduced a new relational data language RLB (Relational data Language with simplified Binary relation handling capability), which can handle bibliographic data as well as data handled by ordinary data base systems. RLB is based on relational calculus introduced by Codd, but allows queries to be written in relatively high level expressions by defining and using proper binary relations over a set of n-ary relations. The characteristics of this language are as follows: (1) Binary relations between attributes or compound attributes can be defined and used to formulate queries; (2) Familiar operations for binary relations such as a concatenation, a closure operation, Boolean operations and comparison operators are provided to simplify queries; (3) Binary relations are classified into several types by their corresponding graphs. This classification can be used for checking storage operations such as updating, insertion and deletion, as well as for selecting efficient physical storage structures; (4) Dependencies between attributes are also regarded as binary relations and thus, they are classified for the same objectives described in (3). In this classification, functional dependencies, multivalued dependencies and set - set dependencies are contained; (5) It can provide several facilities similar to mapping oriented languages (for example, SEQUEL) or network model based languages (for example, LSL). Furthermore, an output system for binary relations between domain compatible attributes is also described, which produces a tree expansion of the given graph.
40817809
Query pairs as hypertext links
A new idea is proposed for constructing object-oriented hypertext database systems: query pairs as hypertext links, where each query is defined over a collection of document objects that are classified using a class hierarchy. With this idea, users need not modify their hypertext links against the insertions, deletions and updates of document objects. Also, when a database schema (here, a class hierarchy) evolves, a systematic method can be considered to modify user-defined query-pair links. The TextLink-III system that was developed based on this idea and that is currently running is described. The notable features of TextLink-III are the following: document objects are classified by class hierarchy and the notion of class expression is used for formulating a query for a class hierarchy; multiple viewpoint support; and less link maintenance against data updates.<<ETX>>
62238493
Two-Level Schemata and Generalized Links for Hypertext Database Models
18847598
A method for panoramic stereo image acquisition
One of the key technologies for one-to-many visual communication is panoramic stereo, in which stereoscopic images for arbitrary horizontal directions are presented to multiple users, according to their positions and postures. In this paper, one of the methods for capturing panoramic stereo motion pictures is proposed and evaluated, along with an experimentation. Through preliminary experimentation, we have confirmed the effectiveness of methods using a curved mirror.
3517036
Fixed Point Theory in Weak Second-Order Arithmetic
Abstract We develop a basic part of fixed point theory in the context of weak subsystems of second-order arithmetic. RCA0 is the system of recursive comprehension and Σ01 induction. WKL0 is RCA0 plus the weak Konig's lemma: every infinite tree of sequences of 0's and 1's has an infinite path. A topological space X is said to possess the fixed point property if every continuous function f:X→X has a point x ϵ X such that f(x) = x. Within WKL0 (indeed RCA0), we prove Brouwer's theorem asserting that every nonempty compact convex closed set C in R n has the fixed point property, provided that C is expressed as the completion of a countable subset of Q n. We then extend Brouwer's theorem to its infinite dimensional analogue (the Tychonoff-Schauder theorem for R N ) still within RCA0. As an application of this theorem, we prove the Cauchy-Peano theorem for ordinary differential equations within WKL0, which was first shown by Simpson without reference to the fixed point theorem. Within RCA0, we also prove the Markov-Kakutani theorem which asserts the existence of a common fixed point for certain families of affine mappings. Adapting Kakutani's ingenious proof for deducing the Hahn–Banach theorem from the Markov-Kakutani theorem, we also establish the Hahn-Banach theorem for seperable Banach spaces within WKL0, which was first shown by Brown and Simpson in a different way.
119404260
Probabilistic image processing based on the Q-Ising model by means of the mean-field method and loopy belief propagation
The framework is presented of Bayesian image restoration for multi-valued images by means of the Q-Ising model. Hyper parameters in the probabilistic model are determined so as to maximize the marginal likelihood. Practical algorithms are described based the conventional mean-field approximation and loopy belief propagation. We compare the results empirically with those provided by conventional filters and the new methods are found to be superior.
11983347
Linear Response Formula in Generalized Belief Propagation for Probabilistic Inference
Linear response formulas for the generalized belief propagation in approximate inference are derived by using generalized belief propagation. The linear response formulas can give us the marginal probability between every pair of nodes and we obtain good accuracy in some examples of practical probabilistic inferences
43363560
Adaptive Dynamic Voltage Scaling for Real-Time Systems