Approved for public release; distribution is unlimited. / Traditional database development has been done for a specific, self-contained purpose with no plan to share or merge the data with other databases in the future. As these systems have matured, users have realized a requirement exists to share their data. Finding common attributes among databases is a time consuming task. However, it is one that is necessary as more and more corporations and agencies consolidate operations. In terms of DoD, the requirement to consolidate systems has come about, as the various data systems used by DoD agencies and our allies need to communicate with each other for a well-coordinated operation. One alternative for achieving the desired interconnectivity is to specify the requirement for interoperability in new systems. A more practical, less costly process is to merge existing systems and consolidate the common components. This paper proposes a process for consolidating portions of data dictionaries of two existing databases. The proposed method uses commercial-off-the-shelf software in finding common attributes between multiple databases and represents an improvement in accuracy and time over previous methods.

Approved for public release; distribution is unlimited / Currently, the most common approach in developing database applications is to use an object-oriented language for the frontend module and a relational database for the backend datastore. The major disadvantage of this approach is the well-known "impedance mismatch" in which some form of mapping is required to connect the objects in the frontend and the relational tuples in the backend. Java Data Objects (JDO) technology is recently proposed Java API that eliminates the impedance mismatch. By using JDO API, the programmers deal strictly with objects. JDO hides the details of the backend datastore by providing the object-oriented view of the datastore. JDO automatically handles the mapping between the objects and the underlying data in the relational database, which is hidden from the programmer. This thesis investigates the effectiveness of JDO. Part of the analysis will develop a database application using JDO. Although JDO provides the benefits of object-orientation in design and implementation of the databases, it is not immune from problems and limitations. The thesis will also analyze the advantages and disadvantages of using JDO and discuss the areas requiring improvements in future releases. / Major, Hellenic Air Force

There have been a number of different versioning models proposed. The research in this area can be divided into two categories: object versioning and schema versioning. In this dissertation, both problem domains are considered as a single unit. This dissertation describes a unifying version model (UVM) for maintaining changes to both objects and schema. UVM handles schema versioning operations by using object versioning techniques. The result is that the UVM allows the OODBMS to be much smaller than previous systems. Also, programmers need know only one set of versioning operations; thus, reducing the learning time by half. This dissertation shows that UVM is a simple but semantically sound and powerful version model for both objects and schema.

Fuzzy attributes are used to quantify imprecise data that model real world objects. To effectively use fuzzy attributes, a fuzzy membership function must be defined to provide the boundaries for the fuzzy data. The initialization of these membership function values should allow the data to converge to a stable membership value in the shortest time possible. The paper compares three initialization methods, Random, Midpoint and Random Proportional, to determine which method optimizes convergence. The comparison experiments suggest the use of the Random Proportional method.

Due to increasing capacity of storage devices and speed of computer networks during last years, it is still more required to sort and search data effectively. Query result containing thousands of rows is usually useless and unreadable. In that situation, users may prefer to define constraints and sorting priorities in the query, and see only several top rows from the result. This thesis deals with top-k queries problems, extension of relational algebra by new operators and their implementation in database system. It focuses on optimization of operations join and sort. The thesis includes implementation and comparison of some algorithms in standalone .NET library NRank.

In the presented work we study evolution of a database schema and its impact on related issues. The work contains a review of important problems related to the change in a respective storage of the data. It describes existing approaches of these problems as well. In detail the work analyzes an impact of database schema changes on database queries, which relate to the particular database schema. The approach presented in this thesis shows a ability to model database queries together with a database schema model. The thesis describes a solution how to adapt database queries related to the evolved database schema. Finally the work contains a number of experiments that verify a proposal of the presented solution.

Approved for public release, distribution is unlimited / The Basic School (TBS) is the first school assignment for all Marine Officers. While assigned to TBS unrestricted ground officers compete for and are assigned a Military Occupational Skill (MOS). The process of educating the Marine Officers about the different MOSs is primarily accomplished by word of mouth at MOS Mixers (social events) and one-on-one discussions. The assignment of the MOS to the Marine Officer is based on the officer's lineal standing within his/her company. Officers are ranked lineally based on a composite score of academic and leadership grades. To ensure a quality distribution of officers into MOSs, the company is divided into thirds (Top, Middle, Bottom) and the vacancies assigned to the company are divided into thirds (Top, Middle, Bottom). Officers compete for an MOS within their assigned third. The current assignment system has remained virtually unchanged over the last thirty years. It is a mostly manually process that provides little visibility of the data, and does not utilize automated information tools for report generation of statistical information. This joint thesis team has developed a Two-Tier Client/Server Information Management System for use by the lieutenants and staff officers of The Basic School and it is called MyMOS. This system was developed using current industry standards that are compliant with those of the Department of Defense. It is the first of its kind at TBS and is designed to be employed as an operational system. MyMOS was designed with an interface that would maximize acceptance and reduce total ownership cost. / Captain, United States Marine Corps / Lieutenant Colonel, United States Marine Corps

Large areas of the UK have witnessed intense industrialisation since the industrial revolution in the latter part of the 18th Century. Increased environmental awareness and pressure to redevelop brown field sites, have resulted in the majority of civil engineering projects undertaken within the UK encountering some form of contamination. In order to collect the vast amount of information required to assess a potentially contaminated site, a multi-stage site investigation (preliminary investigation, exploratory and detailed investigation) is usually undertaken. The information collected during the investigation allows the three components of the risk assessment process to be identified. These components are the source of contamination, possible pathways for the movement of contaminants and vulnerable targets on and off site. A prototype knowledge-based system (ATTIC Assessment Tool for The Investigation of Contaminated Land) has been developed to demonstrate that knowledge-based technology can be applied to the preliminary stage of the investigation of contaminated land. ATTIC assesses information collected during the preliminary stage of an investigation (past use, geological map, hydrological maps etc.) and assists with the risk assessment process, with the prediction of potential contaminants, hazards and risk to neighbouring areas. The system has been developed, using CLIPS software. It consists of four knowledgebases (source, pathway, target and health and safety knowledge-base), containing 1600 rules. The knowledge within the knowledge-bases was obtained from two main sources. The initial and main source was the technical literature. Obtaining knowledge from technical literature involved reviewing published material, extracting relevant information and converting information into rules suitable for the knowledge-base system. The second source of knowledge was domain experts via a knowledge elicitation exercise. The exercise took the form of a questionnaire relating to the rules and parameters within the system. A Visual Basics interface was also developed in conjunction with the knowledge-based system, in order to allow data entry to the system. The interface uses a series of forms relating to different components within the risk assessment process. On completion of compiling the prototype, the system was validated against a number of case studies. The system predicted the likely contaminants with a reasonable match to those observed, even though the input data for the case studies was limited. The assessment of risks to neighbouring target areas was generally in agreement with the case study reports, matching similar risk values and directions. In addition to the development of the prototype system, a database modelled on the Association of Geotechnical Specialists electronic format for the transfer of ground investigation data was also developed to store preliminary investigation information. The data structures were implemented using Microsoft Access relational database management system software. This allowed the database to be developed within a Microsoft Windows environment.

Call number: LD2668 .T4 1986 W546 / Master of Science / Computing and Information Sciences

Call number: LD2668 .T4 1986 P68 / Master of Science / Computing and Information Sciences