• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.4
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• pp.157-170
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• 1999

The web-based groupware systems hold many possibilities for system developers and users. Especially, web-based group collaborative systems are emerging as enterprise-wide information systems. Since data in group collaborative systems are apt to be shared among multiple concurrent users and modified simutaneously by them, the web-based group collaborative systems must support synchronous collaboration in order to provide users with synchronized and consistent views of shared data. However, current web technologies have limitations in supporting this, largely because the existing Hypertext Transfer Protocol(HTTP) is unidirectional and does not allow web servers to send messages to their web browsers without first receiving requests from them. This paper proposes an active web server that can overcome such limitations and facilitate synchronous collaboration in web-based group collaborative systems. To accomplish such goals, the active web server manages dependency relationships beween shared data and web browsers referencing them and actively propagates changing details of the shared data to all web browsers referencing them. And, this paper examines usefulness and effectiveness of the active web server to apply it to the ball-bearing design example of concurrent engineering design systems. The prototype system of the active web server is developed on a commercial Object-oriented Database Management System(0DBMS) called OBJECTSTERE using the C++ programming language.

• Transactions on Control, Automation and Systems Engineering
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• v.1 no.2
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• pp.147-152
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• 1999

It is an interesting area in the field of artifical intelligence to find an analytic model of cooperative structure for multiagent system accomplishing a given task. Usually it is difficult to design controllers for multi-agent systems without a comprehensive knowledge about the system. One of the way to overcome this limitation is to implement an evolutionary approach to design the controllers. This paper introduces the use of a genetic algorithm to discover a fuzzy logic controller with rules that govern emergent agents solving a pursuit problem in a continuous world. Simulation results indicate that, given the complexity of the problem, an evolutionary approach to find the fuzzy logic controller seems to be promising.

• Transactions on Control, Automation and Systems Engineering
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• v.4 no.4
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• pp.324-329
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• 2002

In this paper, the guaranteed cost filtering design method for linear time delay systems with convex bounded uncertainties in discrete-time case is presented. The uncertain parameters are assumed to be unknown but belonging to known convex compact set of polytotype less conservative than norm bounded parameter uncertainty. The main purpose is to design a stable filter which minimizes the guaranteed cost. The sufficient condition for the existence of filter, the guaranteed cost filter design method, and the upper bound of the guaranteed cost are proposed. Since the proposed sufficient conditions are LMI(linear matrix inequality) forms in terms of all finding variables, all solutions can be obtained simultaneously by means of powerful convex programming tools with global convergence assured. Finally, a numerical example is given to check the validity of the proposed method.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.11
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• pp.1891-1908
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• 2011

Cyber-physical systems (CPSs) are an emerging discipline that involves engineered computing and communicating systems interfacing the physical world. The widespread applications of CPSs still face enormous challenges because of the lack of theoretical foundations. In this technical survey, we review state-of-the-art design techniques from various angles. The aim of this work is to provide a better understanding of this emerging multidisciplinary methodology. The features of CPSs are described, and the research progress is analyzed using the following aspects: energy management, network security, data transmission and management, model-based design, control technique, and system resource allocation. We focus on CPS resource optimization, and propose a system performance optimization model with resource constraints. In addition, some classic applications (e.g., integrating intelligent road with unmanned vehicle) are provided to show that the prospects of CPSs are promising. Furthermore, research challenges and suggestions for future work are outlined in brief.

• The Journal of Industrial Distribution & Business
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• v.6 no.3
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• pp.5-8
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• 2015

Purpose - This article's aim is to examine how the utilization of existing and future decision-support systems will lead to a change in the auditing process. Research design, data, and methodology - An information system is a special decision-support system that combines information obtained from various sources and communicates among them to help in assessing appropriate complex financial decisions. This paper analyzes techniques such as data and text mining as components of decision-support systems to be used in the auditing process. Results - We present views about how existing decision-support systems will lead to a change in audits. Auditors, who currently collect significant data manually, will in the future move towards management through complex decision-support systems. Conclusions - Although some internal audit functions are integrated into systems of continuous monitoring, the use of such systems remains limited. Thus, instead of multiple decision-support systems, a unified decision-support system can be deployed for this that includes sensors integrated within a company in different contexts (e.g., production, sales, and accounting) that continually monitors violations of controls, unusual patterns, and unusual transactions.

• Journal of information and communication convergence engineering
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• v.8 no.5
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• pp.473-478
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• 2010

Today's engineering design is carried out in a distributed fashion geographically or physically. This places new requirements on the computational environments such as efficient integration and collaboration. With the advances of the Internet and Network environment recently, many researches have been proposed and at the same time, Web-based distributed design gives to a new paradigm in design and manufacturing fields. That is, Web-based technologies lead to reduce the product development times and to ensure a competitive product in order to exchange and interact of real-time design information that integrates the distributed design environment between departments as well as companies via Internet and Web. So, an efficient data communication for design information sharing is the foundation for collaborative systems in the distributed environment. Design data communication techniques such as CORBA, DCOM and RMI have been considered in the existing research but they have some problems that are limitations of interoperability and firewall problems in the Web. Therefore, this paper presents a Web-based distributed design application where distributed design information resources are integrated and exchanged using Web Services for supporting XML and HTTP without the interoperability and firewall problems through the 330K VLCC case.

• Asia pacific journal of information systems
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• v.8 no.3
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• pp.37-49
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• 1998

The basic goal of CALS is to improve transactions and relationships among organizations through information sharing and integration. CALS is an information strategy which needs strong cooperation between organizations or between users and developers in design step. However, current design methodologies using IDEF models, that are considered to be standard for CALS system development, has some limitations. For example, it is difficult for system developers to communicate with counterparts by IDEF model since IDEF models are difficult for counterparts to understand. In this paper, we suggest a development methodology for GALS systems by complementing IDEF model with Document Trace Diagram, which we developed as a communication tool, The concept of Document Trace Diagram stems from the fact that most information exchanged within or between organizations is in the form of documents and most standard operating procedures of organizations are about processing the documents. It helps system developers identify functions and their ICOMs (Input, Control, Output, Mechanism) with ease and little communication cost. With this methodology, we have constructed the GALS prototype system for construction industry.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.6-8
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• 2009

In this paper. we propose receiver algorithms for VHF(Very High Frequency) digital link mode-2(VDL Mode-2) systems. Unlike conventional digital communication systems using the root raised cosine filter as a transmit and receive filter, raised cosine filter is used as a transmit filter in VDL Mode-2 systems. Hence, it is crucial to design and implement the optimum lowpass receive filter by considering the amount of inter-symbol interference and noise performance. On the other hand, due to the short preamble pattern, it is crucial to develop an efficient packet detection algorithm for reliable communication link. In this paper, we design the optimum receive filter and packet detection algorithm and evaluate the performance of receiver adopting the proposed receive filter and packet detection algorithm.

• Journal of Information Technology Services
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• v.7 no.1
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• pp.205-218
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• 2008

This paper proposes a geospatial data visualization system supporting validation of GML documents. GIS systems manage and use both of spatial and non-spatial data. Currently, most GIS systems represent spatial data in GML (Geography Markup Language) developed by OGC. GML is a language for representation and sharing of spatial information, and until now many systems have been developed in GML. GML does not support expression of non-spatial data, i.e., relational information of spatial objects, and thus most systems extend GML to describe non-spatial information. However, it causes an issue that the systems only accepting standard GML documents cannot process the extended documents. In this paper, we propose a new GIS data visualization system to resolve the aforementioned Issue. Our proposed system allows the representation of both types of data supporting independency of spatial data and non-spatial data. It enhances interoperability with other relevant systems. Therefore, we can develop a rich and high Quality geospatial information services.

• Journal of the Korea Institute of Military Science and Technology
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• v.18 no.3
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• pp.260-266
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• 2015

The warship is run based on the combat system which shares tactical information collected by target detection systems and navigation devices across a network, and conducts the command and control of weapons from target detection to kill assessment. The short-range air defense missile system defends a warship from anti-ship missiles, aircraft, helicopter and other threats in order to contribute to the survival of a warship and the success of missions. The short-range air defense missile system is applied to a various combat systems. In this paper, we have proposed the interface design between the short-range air defense missile and dissimilar combat systems. To employ the short-range air defense missile at dissimilar combat systems, each system is driven by independent processor, and the tasks which are performed by each system are assigned. The information created by them is exchanged through the interface, and the flow of messages is designed.