A multiresolution representation scheme for multimedia databases

We present a compression scheme that is useful for interactive video applications such as browsing a multimedia database. The focus of our approach the development of a compression scheme (and a corresponding retrieval scheme) that is optimal for any data rate. To browse a multimedia database, such a compression scheme is essential. We use a multiresolution setting, but eliminate the need for wavelets. This results in much better compression. We show experimental results and explain in detail how to extend our approach to multidimensional data.     

A representation independent language for planar spatial databases with Euclidean distance

Linear constraint databases and query languages are appropriate for spatial database applications. Not only is the data model suitable for representing a large portion of spatial data such as in GIS systems, but there also exist efficient algorithms for the core operations in the query languages. An important limitation of linear constraints, however, is that they cannot model constructs such as Euclidean distance; extending such languages to include such constructs, without obtaining the full power of polynomial constraints has proven to be quite difficult.One approach to this problem, by Kuijpers, Kuper, Paredaens, and Vandeurzen, used the notion of Euclidean constructions with ruler and compass as the basis for a first order query language. While their language had the desired expressive power, the semantics are not really natural, due to its use of an ad hoc encoding. In this paper, we define a language over a similar class of databases, with more natural semantics. We show that this language captures a natural subclass, the representation independent queries of the first order language of Kuijpers, Kuper, Paredaens, and Vandeurzen.     

2D Z-string: A new spatial knowledge representation for image databases

The knowledge structure called the 2D C⁺-string, proposed by Huang et al., to represent symbolic pictures allows a natural way to construct iconic indexes for images. According to the cutting mechanism of the 2D C⁺-string, an object may be partitioned into several subparts. The number of partitioned subparts is bounded to O(n²), where n is the number of objects in the image. Hence, the string length is also bounded to O(n²). In this paper, we propose a new spatial knowledge representation called the 2D Z-string. Since there are no cuttings between objects in the 2D Z-string, the integrity of objects is preserved and the string length is bounded to O(n). Finally, some experiments are conducted to compare the performance of both approaches.     

Set-oriented data mining in relational databases

Data mining is an important real-life application for businesses. It is critical to find efficient ways of mining large data sets. In order to benefit from the experience with relational databases, a set-oriented approach to mining data is needed. In such an approach, the data mining operations are expressed in terms of relational or set-oriented operations. Query optimization technology can then be used for efficient processing.

In this paper, we describe set-oriented algorithms for mining association rules. Such algorithms imply performing multiple joins and thus may appear to be inherently less efficient than special-purpose algorithms. We develop new algorithms that can be expressed as SQL queries, and discuss optimization of these algorithms. After analytical evaluation, an algorithm named SETM emerges as the algorithm of choice. Algorithm SETM uses only simple database primitives, viz., sorting and merge-scan join. Algorithm SETM is simple, fast, and stable over the range of parameter values. It is easily parallelized and we suggest several additional optimizations. The set-oriented nature of Algorithm SETM makes it possible to develop extensions easily and its performance makes it feasible to build interactive data mining tools for large databases.     

Partitioned data objects in distributed databases

In many distributed databases locality of reference is crucial to achieve acceptable performance. However, the purpose of data distribution is to spread the data among several remote sites. One way to solve this contradiction is to use partitioned data techniques. Instead of accessing the entire data, a site works on a fraction that is made locally available, thereby increasing the site's autonomy. We present a theory of partitioned data that formalizes the concept and establishes the basis to develop a correctness criterion and a concurrency control protocol for partitioned databases. Set-serializability is proposed as a correctness criterion and we suggest an implementation that integrates partitioned and non-partitioned data. To complete this study, the policies required in a real implementation are also analyzed. Recommended by: Hector Garcia-Molina     

Mining frequent patterns in image databases with 9D-SPA representation

In this paper, we propose a novel algorithm, called 9DSPA-Miner, to mine frequent patterns from an image database, where every image is represented by the 9D-SPA representation. Our proposed method consists of three phases. First, we scan the database once and create an index structure. Next, the index structure is scanned to find all frequent patterns of length two. Finally, we use the frequent k-patterns (k ? 2) to generate candidate (k + 1)-patterns and check if the support of each candidate generated is not less than the user-specified minimum support threshold by using the index structure. Then, the steps in the third phase are repeated until no more frequent patterns can be found. Since the 9DSPA-Miner algorithm uses the characteristics of the 9D-SPA representation to prune most of impossible candidates, the experiment results demonstrate that it is more efficient and scalable than the modified Apriori method.     

Efficient representation and algebraic manipulation of infinite relations in paraconsistent databases

Paraconsistent information is information that is incomplete and/or inconsistent. A data model for handling paraconsistent information in relational databases has recently been developed. In this paper, we show that a DBMS based on paraconsistent relations must be capable of handling infinite relations. We also identify classes of infinite paraconsistent relations whose members can be effectively represented and manipulated. We show that the classes of REGULAR and, under different conditions, CONTEXT-SENSITIVE as well as PSPACE paraconsistent relations are such. We also show that the CONTEXT-FREE and R.E. classes do not have the desired properties, while P, NP, LOGSPACE and NLOGSPACE also probably do not. These results help identify the kinds of relational DBMS that can be constructed for handling incomplete and inconsistent information about tuples. We finally show that all operations for the aforementioned PSPACE and CONTEXT-SENSITIVE cases can be carried out efficiently in polynomial time.     

Performance analysis of compaction techniques for map representation in geographic databases

A new compaction scheme for representing cellular thematic maps in geographic databases is presented. The memory saving provided by this method, called Hierarchical Compaction Scheme (HCS) is analyzed and compared to that of two more classical cellular schemes. HCS not only provides a significant compaction ratio but also renders processing operations such as map intersection or union easier. It also allows the use of variable scale.     

一种海量的人口信息存储与复制策略

在分析公安信息系统环境和持征的基础上,提出了一种适合公安信息系统的海量人口信息存储与复制策略,该策略采用多数据库结构,实现了数据访问的负载分担,大大提高PSMIS的访问性能,可用性和可靠性,同时,该策略支持可接受的数据弱一致性,能够使多数据库系统在有限的时间内收敛,达到各个数据节点数据完全一致,因而该策略能够很好的应用于公安信息系统的海量人口信息管理系统。     

A uniform formal description of data base management systems

This paper attempts for the first time to formulate the majority of data base functions in an homogeneous and formal manner, in contrast to other methods which treat little more than the data manipulation functions. The main task of a data base management system is to execute certain uniform operations on a given set of data resources. Most problems of data base management systems can be deducted from this main task, in that a framework is provided both for investigating existing systems or designing new ones.     

A search space reduction methodology for data mining in large databases

Given the present need for Customer Relationship and the increased growth of the size of databases, many new approaches to large database clustering and processing have been attempted. In this work, we propose a methodology based on the idea that statistically proven search space reduction is possible in practice. Two clustering models are generated: one corresponding to the full data set and another pertaining to the sampled data set. The resulting empirical distributions were mathematically tested to verify a tight non-linear significant approximation.     

Models of representation of fuzzy temporal knowledge in databases of temporal series

the problem of representation of fuzzy knowledge in databases of temporal series is considered. The existing approaches to formalization and search of temporal knowledge in such databases are described. A new class of models for representation of fuzzy temporal knowledge in databases of time series is proposed in order to support the processes of knowledge revealing. The methodology of estimating the efficiency of representations based on the use of general-system principles of human thinking and speaking communication is presented. Based on the selected system of criteria, the advantages of the proposed class of models are substantiated.     

Enhanced abstract data types in object-relational databases

The explosion in complex multimedia content makes it crucial for database systems to support such data efficiently. This paper argues that the “blackbox” ADTs used in current object-relational systems inhibit their performance, thereby limiting their use in emerging applications. Instead, the next generation of object-relational database systems should be based on enhanced abstract data type (E-ADT) technology. An (E-ADT) can expose the semantics of its methods to the database system, thereby permitting advanced query optimizations. Fundamental architectural changes are required to build a database system with E-ADTs; the added functionality should not compromise the modularity of data types and the extensibility of the type system. The implementation issues have been explored through the development of E-ADTs in Predator. Initial performance results demonstrate an order of magnitude in performance improvements. Received January 1, 1998 / Accepted May 27, 1998     

A new pattern representation scheme using data compression

We propose the PRDC (Pattern Representation based on Data Compression) scheme for media data analysis. PRDC is composed of two parts: an encoder that translates input data into text and a set of text compressors to generate a compression-ratio vector (CV). The CV is used as a feature of the input data. By preparing a set of media-specific encoders, PRDC becomes widely applicable. Analysis tasks - both categorization (class formation) and recognition (classification) - can be realized using CVs. After a mathematical discussion on the realizability of PRDC, the wide applicability of this scheme is demonstrated through the automatic categorization and/or recognition of music, voices, genomes, handwritten sketches and color images     

A data model and a query languagefor multimedia documents databases

A multimedia application involves information that may be in a form of video, images, audio, text and graphics, need to be stored, retrieved and manipulated in large databases. In this paper, we propose an object-oriented database schema that supports multimedia documents and their temporal, spatial and logical structures. We present a document example and show how the schema can adress all the structures described. We also present a multimedia query specification language that can be used to describe a multimedia content portion to be retrieved from the database. The language provides means by which the user can specify the information on the media as well as the temoral and spatial relationships among these media.     

Appropriate inferences of data dependencies in relational databases

We study inference systems for the combined class of functional and full hierarchical dependencies in relational databases. Two notions of implication are considered: the original notion in which a dependency is implied by a given set of dependencies and the underlying set of attributes, and the alternative notion in which a dependency is implied by a given set of dependencies alone. The first main result establishes a finite axiomatisation for the original notion of implication which clarifies the role of the complementation rule in the combined setting. In fact, we identify inference systems that are appropriate in the following sense: full hierarchical dependencies can be inferred without use of the complementation rule at all or with a single application of the complementation rule at the final step of the inference only; and functional dependencies can be inferred without any application of the complementation rule. The second main result establishes a finite axiomatisation for the alternative notion of implication. We further show how inferences of full hierarchical dependencies can be simulated by inferences of multivalued dependencies, and vice versa. This enables us to apply both of our main results to the combined class of functional and multivalued dependencies. Furthermore, we establish a novel axiomatisation for the class of non-trivial functional dependencies.     

A data representation code for text processing systems

A brief analysis of character strings and string processing is given. Text processing is defined as the processing of character strings to control not only the sequential relations among the characters, but also spatial and form relations among the symbols used to produce a physical display of the character string. Requirements are given for a data structure by which character strings may be represented to facilitate text processing, including independent manipulation of sequential, spatial, and form relations. A Text Processing Code (TPC) meeting these requirements is presented in detail. Several other coding schemes are examined and shown to be inadequate for text processing as defined here.     

A nonblocking transaction data flow graph based protocol forreplicated databases

Replicated data management systems adopt the 1-copy serializability criteria for processing transactions. In order to achieve this goal, many approaches rely on obtaining votes from other sites for processing update requests. In the proposed approach, a technique for generation of precedence graphs for each transaction execution is analyzed. The transaction data flow graph approach is a fully distributed approach. The proposed technique, is free from deadlocks, and avoids resubmission of transactions