There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

物件導向軟體之架構(Object-Oriented Software Construction)探討

We address the problem of providing integrated access to diverse and dynamic information sources. We explain how this problem differs from the traditional database integration problem and we focus on one aspect of the information integration problem, namely information exchange. We define an object-based information exchange model and a corresponding query language that we believe are well suited for integration of diverse information sources. We describe how, the model and language have been used to integrate heterogeneous bibliographic information sources. We also describe two general-purpose libraries we have implemented for object exchange between clients and servers. >

Object exchange across heterogeneous information sources

TSIMMIS—The Stanford-IBM Manager of Multiple Information Sources—is a system for integrating information It offers a data model and a common query language that are designed to support the combining of information from many different sources It also offers tools for generating automatically the components that are needed to build systems for integrating information In this paper we shall discuss the principal architectural features and their rationale

/pdf/the-tsimmis-approach-to-mediation-data-models-and-languages-42rujevnls.pdf

The TSIMMIS Approach to Mediation: Data Models and Languages

Tougher competitive situations have led to increasing attention being paid to customer satisfaction, of which timely and customized services are the key concepts. As the product life cycle becomes shortened, high product quality becomes necessary for survival. Markets become highly diversified and global, and continuous and unexpected change become the key factors for success. The need for a method of rapidly and cost-effectively developing products, production facilities and supporting software, including design, process planning and shop floor control system has led to the concept of agile manufacturing. Agile manufacturing can be defined as the capability to survive and prosper in a competitive environment of continuous and unpredictable change by reacting quickly and effectively to changing markets, driven by customer-designed products and services. This article details the key concepts and enablers of agile manufacturing. The key enablers of agile manufacturing include: (i) virtual enterprise formati...

Agile manufacturing: enablers and an implementation framework

The objective of a multidatabase system is to provide a single uniform interface to accessing multiple independent databases being managed by multiple independent, and possibly heterogeneous, database systems. One crucial element in the design of a multidatabase system is the design of a data definition language for specifying a schema that represents the integration of the schemas of multiple independent databases. The design of such a language in turn requires a comprehensive classification of the conflicts (i.e., discrepancies) among the schemas of the independent databases and development of techniques for resolving (i.e., homogenizing) all of the conflicts in the classification. An earlier paper provided a comprehensive classification of schematic conflicts that may arise when integrating multiple independent relational database (RDB) schemas into a single multidatabase (MDB) schema. In this paper, we provide a comprehensive classification of techniques for resolving the schematic conflicts that may arise when integrating multiple RDB schemas, or RDB schemas and object-oriented database (OODB) schemas, or multiple OODB schemas. The classification of conflict resolution techniques includes not only those necessary for resolving schematic conflicts identified in the earlier paper, but also additional conflicts that arise when OODBs become part of the databases to be integrated. Most of the conflict resolution techniques discussed in the paper have already been incorporated into SQL/M, a multidatabase language implemented in UniSQL/M, a commercially available multidatabase system from UniSQL, Inc. which integrated SQL-based relational database systems and the UniSQL/X unified relational and object-oriented database system.

On resolving schematic heterogeneity in multidatabase systems

An integration architecture for knowledge management systems and business process management systems

STEP-NC, a new data model for CAD-CAM-CNC chain, is expected to encompass the whole scope of e-manufacturing. The new data model formalized as ISO 14649 is under development by ISO TC184 SC1 and SC4 for the replacement of the old standard so-called G&M codes, formalized as ISO 6983 which has been used since the 1950s. As the new data model is being established, development and implementation of STEP-compliant CAD/CAM/CNC system based on the new data model is drawing worldwide attention. Several systems have been reported in such international conventions as the ISO Expert Committee Meeting. Up to the present time, all the STEP-CNC systems are intended for milling operation. In this paper, the authors first present STEP-compliant CNC system for turning system including the data model, followed by a generic architecture and functionality. Implementation results obtained from a prototype system called TurnSTEP have been provided. Based on the results, the authors are convinced of the validity of the STEP-NC data model together with the effectiveness of the STEP-CNC system for turning.

STEP-compliant CNC system for turning: Data model, architecture, and implementation

An XML-based process definition language for integrated process management

We present an efficiency model for data warehouse operations and analyze a data set to evaluate the model. The model contains salient variables to evaluate the efficiency of an organization's data warehouse operations for refresh processing and query production. The variables in the model include resource consumption (labor usage and computing budgets), system usage measures (users and queries), quality measures (data age and availability), and a size measure (change data amount). We report on the evaluation of a data set collected from USA and non USA-based (mostly Korean) organizations using input-oriented Data Envelopment Analysis. The analysis indicates wide dispersions in reported data, large differences in labor budgets between efficient and inefficient firms, few organizations efficient in both refresh processing and query production, and the difficulty of providing some data (computing budgets and flexibility ratio). Follow-up interviews with selected organizations provided insights about the value of efficiency comparisons of information technology organizations and suggestions to improve the model.

https://papers.ssrn.com/sol3/Delivery.cfm/SSRN_ID1026068_code810349.pdf?abstractid=1026068&mirid=1&type=2

Injun Choi

Papers

On resolving schematic heterogeneity in multidatabase systems

An integration architecture for knowledge management systems and business process management systems

STEP-compliant CNC system for turning: Data model, architecture, and implementation

An XML-based process definition language for integrated process management

Efficiency Evaluation of Data Warehouse Operations