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Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Declarative development of the presentation level of database-driven information systems was always a main goal for the development technologies. However, it is just partially attained, for a limited set of design patterns, while the general approaches still rely on procedural code. This paper formally defines a set of integrity constraints, as part of a presentation-purpose logical data model. The automatic enforcement of the respective integrity constraints constitutes the declarative support for any implementation technology of the proposed presentation model.

Relational databases are one of the pillars of information systems and as a consequence conceptual and logical design can be seen as the foundation of almost every application regardless of the platform. Nevertheless, little research has been done so far on the effectiveness of teaching approaches to database basic concepts and design. This paper introduces a multi-level experimental study developed to examine the effectiveness of learning database fundamentals, depending on the notation used for conceptual design. The main experiment was carried out at a higher education institution. We developed different experimental instruments to evaluate the effectiveness of a teaching approach using Barker or Bachman notation for conceptual database design. In contrast to Barker notation, Bachman notation incorporates elements of logical design (i.e. foreign keys) in the conceptual design level. Students' achievements were examined with regard to influencing factors throughout the learning process. Introducing the Bachman notation and a manual transformation from a conceptual into a logical data model, could increase students' understanding of conceptual, logical and relational data model concepts. We found that the notation used during the learning process has an impact on students' achievements. Moreover, students achieved better results when solving tasks presented with a notation that incorporates elements of logical design into the conceptual level. Finally, we required the use of manual transformation from a conceptual into a logical data model and the results confirmed an increase in students' understanding. [ABSTRACT FROM AUTHOR]

Current technologies employed for user interface development in database-driven information systems have a procedural approach – they need to specify HOW the business rules should be enforced, through a sequence of operations on data (e.g., create, retrieve, update, delete). Therefore, the development process is time-consuming and error prone. This paper proposes a logical data model – inspired by and complementary to the relational model – which allows a declarative approach in application development. We also present an example which specifies, in terms of the proposed model, WHAT data integrity constraints should be (automatically) enforced be the system.

Declarative development of the presentation level of database-driven information systems was always a main goal for the development technologies. However, it is just partially attained, for a limited set of design patterns, while the general approaches still rely on procedural code. This paper formally defines a set of integrity constraints, as part of a presentation-purpose logical data model. The automatic enforcement of the respective integrity constraints constitutes the declarative support for any implementation technology of the proposed presentation model. [ABSTRACT FROM AUTHOR]

Today, e-commerce is increasingly becoming the norm for business transactions, and relational databases are becoming a necessary tool used for those transactions. As such, business students, including tourism management students and marketing students preparing to work in customer relationship management are expected to be literate in database management. One of the most important and complex concepts in the design of a relational database is normalization. Normalization is the process of organizing data into tables and establishing the relationships among those tables according to the rules designed to eliminate anomalies related to insertions, updates and deletions in the database. Because normalization is a logical design method, it is not industry specific. The tourism industry utilizes e-commerce and thus, databases extensively; however, the authors have not seen a normalization example using tourism data. This paper, will discuss normalization, using a real-world project applicable to the tourism industry. [ABSTRACT FROM AUTHOR]

Abstract: A novel and attractive protocol to synthesis indole-2,3-diones and 2-hydroxy-3(2H)-benzofuranones and via copper(II) oxide catalyzed intramolecular cyclization is described. This method possesses functional-group compatibility, easy workup procedure, shorter reaction time and high yields. [Copyright &y& Elsevier]

SkyServer is the primary catalog data portal of the Sloan Digital Sky Survey that makes multiple terabytes of astronomy data available to the world. Here, the process is described of collecting and analyzing the complete record of more than 10 years of Web hits and SQL queries to SkyServer. [ABSTRACT FROM PUBLISHER]

A comprehensive analysis of 10 years of Web and SQL traffic on SkyServer--the online portal to the multiterabyte Sloan Digital Sky Survey archive--shows the impressive reach of the SDSS to the research community and the public, and provides insight into how methods of e-science are being taken up by the scientific community. [ABSTRACT FROM PUBLISHER]

We propose a mapping from a database conceptual design to a schema for XML that produces highly connected and nested XML structures. We first introduce two alternative definitions of the mapping, one modeling entities as global XML elements and expressing relationships among them in terms of keys and key references (flat design), the other one encoding relationships by properly including the elements for some entities into the elements for other entities (nest design). Then we provide a benchmark evaluation of the two solutions showing that the nest approach, compared to the flat one, leads to improvements in both query and validation performances. This motivates us to systematically investigate the best way to nest XML structures. We identify two different nesting solutions: a maximum depth nesting, that keeps low the number of costly join operations that are necessary to reconstruct information at query time using the mapped schema, and a maximum density nesting, that minimizes the number of schema constraints used in the mapping of the conceptual schema, thus reducing the validation overhead. On the one hand, the problem of finding a maximum depth nesting turns out to be NP-complete and, moreover, it admits no constant ratio approximation algorithm. On the other hand, we devise a graph-theoretic algorithm, NiduX, that solves the maximum density problem in linear time. Interestingly, NiduX finds the optimal solution for the harder maximum depth problem whenever the conceptual design graph is either acyclic or complete. In randomly generated intermediate cases of the graph topology, we experimentally show that NiduX finds a good approximation of the optimal solution. [ABSTRACT FROM AUTHOR]

Current technologies employed for user interface development in database-driven information systems have a procedural approach - they need to specify HOW the business rules should be enforced, through a sequence of operations on data (e.g., create, retrieve, update, delete). Therefore, the development process is time-consuming and error prone. This paper proposes a logical data model - inspired by and complementary to the relational model - which allows a declarative approach in application development. We also present an example which specifies, in terms of the proposed model, WHAT data integrity constraints should be (automatically) enforced be the system. [ABSTRACT FROM AUTHOR]

The article deals with the relational schemes defined on the reduced sets of functional dependencies divided into equivalence classes. The concepts of non-essential and recoverable attributes are introduced, and the algorithms for their computing are proposed. Some properties of schemes, based on these attributes, are presented as well. Based on non-essential and recoverable attributes some conditions are introduced to make a relation be in the third or Boyce-Codd normal form. These conditions are just sufficient, because there could be a scheme that is in third or Boyce-Codd normal form but doesn't satisfy them. In addition, the article suggests a normalization algorithm that takes into account these conditions. [ABSTRACT FROM AUTHOR]

Open Process Automation is an industry standards initiative whose objective is to bring open architecture technology and business practices into the industrial control system industry. More than 100 organizations (operating companies, hardware and software suppliers, system integrators) are working in a managed Forum of The Open Group to define the Open Process Automation Standard (O-PAS TM). Three versions of the O-PAS standard have been published. The paper provides an overview of the standard. The paper also describes results from two O-PAS prototyping projects by ExxonMobil and Lockheed Martin – a laboratory proof-of-concept and a hydrocarbon process-controlling prototype system. Finally, the paper relates Open Process Automation and two complementary initiatives by NAMUR, i.e., NAMUR Open Architecture (NOA) and Module Type Package (MTP). [ABSTRACT FROM AUTHOR]

Autosymmetric functions exhibit a special type of regularity that can speed-up the minimization process. Based on this autosymmetry, we propose a three level form of logic synthesis, called ORAX (EXOR-AND-OR), to be compared with the standard minimal SOP (Sum of Products) form. First we provide a fast ORAX minimization algorithm for autosymmetric functions. The ORAX network for a function f has a first level of at most 2( n− k) EXOR gates, followed by the AND-OR levels, where n is the number of input variables and k is the “autosymmetry degree” of f. In general a minimal ORAX form has smaller size than a standard minimal SOP form for the same function. We show how the gain in area of ORAX over SOP can be measured without explicitly generating the latter. If preferred, a SOP expression can be directly derived from the corresponding ORAX. A set of experimental results confirms that the ORAX form is generally more compact than the SOP form, and its synthesis is much faster than classical three-level logic minimization. Indeed ORAX and SOP minimization times are often comparable, and in some cases ORAX synthesis is even faster. [ABSTRACT FROM AUTHOR]