• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.10
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• pp.410-417
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• 2018

System design errors are more likely to occur in modern systems because of their steadily increasing size and complexity. Failures due to system design errors can cause safety-related accidents in the system, resulting in extensive damage to people and property. Therefore, international standards organizations, such as the U.S. Department of Defense and the International Electrotechnical Commission, have established international safety standards to ensure system safety, and recommend that system design and safety activities should be integrated. Recently, the safety of a system has been verified by modeling through a model-based system design. On the other hand, system design and safety activities have not been integrated because the model for system design and the failure model for safety analysis and verification were developed using different modeling language platforms. Furthermore, studies using UML or SysML-based failure models for deriving safety requirements have shown that these models have limited applicability to safety analysis and verification. To solve this problem, it is essential to extend the existing methods for failure model implementation. First, an improved SysML-based failure model capable of integrating system design and safety verification activities should be produced. Next, this model should help verify whether the safety requirements derived via the failure model are reflected properly in the system design. Therefore, this paper presents the concept and method of developing a SysML-based failure model for an automotive system. In addition, the failure model was simulated to verify the safety of the automotive system. The results show that the improved SysML-based failure model can support the integration of system design and safety verification activities.

• Journal of the Korea Society for Simulation
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• v.3 no.1
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• pp.151-165
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• 1994

Broadband network based on the Asynchronous Transfer Mode(ATM) concept are becoming the target technology for the emerging Broadband Integrated Services Digital Network(B-ISDN). Since B-ISDN is very complex and requites a great amount of investment, optimum design and performance analysis of such systems are very important. Simulation can be widely used to analyze and examine the broadband network behavior. However, for the complicated system like broadband networks it is extremely difficult and time-consuming to develop a complete model for simulation. In this paper, an object-oriented modeling approach for the broadband network simulation is presented for the effective and efficient modeling. Object-oriented approaches can provide a good structuring capability for complicated simulation models and facilitate the development of reusable and extensible simulation models. We have developed an object-oriented model which consists of object model and behavior model. In the object mode., the components of the broadband network and both constant bit rate(CBR) and variable bit rate(VBR) traffic types of call level, burst level, and cell level are modeled as object classes. In the behavior model, the dynamic features for each object class are represented using the state transition diagram. It has been shown by illustration that objectoriented modeling is an effective tool for modeling the complicated B-ISDN.

• Journal of the Korea Society of Computer and Information
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• v.4 no.2
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• pp.46-60
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• 1999

Recently, CTI (Computer Telephony Integration) technology has been widely applied to various area such as video conference, file transfer, voice mail, automatic message transfer and automatic redial, integrated messaging and network fax. In this paper, an administrative affairs supporting system using call control mode of CTI is designed. To improve inefficient processing of job due to heavy calling from entrance candidates during entrance examination of a college, the system is developed. The database of the system is desigend using object modeling technique. Also, the automatic calling and response system using CTI call control mode is implemented. Especially, to interface with voice of candidates who ask whether they pass or fail the entrance examination of the college, TTS(Text To Speech) module is developed.

• Journal of Ocean Engineering and Technology
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• v.22 no.2
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• pp.78-84
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• 2008

As a preliminary step to build a complete superyacht hull design program, the development of superyacht profile design system is introduced. The two-dimensional hull profile is decomposed into four local zones depending upon the functionality and connecting continuity of the profile. Characteristics of each zone are investigated and used to generate the model describing the geometric shape of zone using freeform curves. A set of design parameters is derived from the established geometric model. Generation and modification of a model are is by manipulating the chosen parameters. Four zones designed are integrated to form a final profile. An interactive design system performing all the modeling and modification processes is implemented using the graphic user interface system based an Microsoft Foundation Class and OpenCASCADE, a open graphic library. The shapes of the profiles generated by the developed design system are verified with those of built superyachts. The developed design system will be used for the construction of three-dimensional superyacht hull modeling system.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.2
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• pp.115-123
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• 2018

This study is empirically intended to put forward the modeling and process improvement measures for the SCM capability in small venture firms. The findings are summarized as follows. There were strategic alliance, technological development and centralization in the modeling of strategic planning for supply chain, not the least of which is strategic alliance, followed by centralization and technological development. There were routing scheduling, network integration and third party logistics outsourcing in decision making, not the least of which was network integration. There were customer service management, productivity management and quality management in management control, not the least of which was quality management. And there were order management choice, pricing demand, shipment delivery and customer management in transaction support system, not the least of which was order management choice. As for the above-mentioned findings, to maximize the SCM capability and operate the optimized process in small venture firms, the existing strategic alliances can optimize the quality management and stabilize the transaction support system through the network sharing and integration from the perspective of relevant organizational members' capability and process improvement. And the strategic linkage between firms can maximize the integrated capability of information system beyond the simple exchange relation between electronic data, achieving a differentiated competitive advantage. Consequently, the systematization and centralization for the maximization of SCM capability, including the infrastructure construction based on the system compatibility and reliability for information integration, should be preceded before the modeling of the integrated capability for optimum supply chain and the best process management in the smart era.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.163-167
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• 1999

The relational data model can't be applied to CAD/CAM, CE, and CIM since it can't support the semantic model concept such as complex object, random data definition, manipulation, version control, generalization, aggregation and so on. In this paper, the IPCS(Integrated Production Control System) for hand-rail of ship is parted into several module according to process function. further more, the object oriented data model is designed with UML(Unified Modeling Language). UML is the object oriented design methodology of industrial standard that combines the Booch's methodology, the Rumbaugh's On(Object Modeling Technique), and the Jacobson's OOSE(Object-Oriented Software Engineering) methodology. The efficient management is expected with object-oriented data model construction, since this developed system can achieve efficient process control, system maintenance, repair and extension.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.12B
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• pp.1227-1235
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• 2010

Stateflow is a useful system modeling tool, which is frequently used in industry. But Stateflow has defects when users are trying to describe consecutive behaviors or a system's temporal behaviors. Timing diagram, on the other hand, is a widely used tool of explaining behaviors of a hardware system in electronics. This tool has a merit when specifying consecutive behaviors and temporal behaviors of a system. Thus, this paper suggests $Stateflow_{TD}$, the unified modeling methodology in Stateflow domain integrating Stateflow with Timing diagram in order to improve the shortcomings of Stateflow. This paper not only explains a technique of integrating both a Stateflow model and Timing diagram models, and describes advantages of what $Stateflow_{TD}$ formalism has, but also shows its convenience using two example systems.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.1
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• pp.45-54
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• 2011

A program aiming at predicting dynamic characteristics of a Liquid Rocket Engine(LRE) was developed and examined to trace entire LRE operation. In the startup period, transient characteristics of the propellant flows were predicted and validated with hydraulic tests data. An arrangement of each component for the pipelines was based on an operating circuit of open cycle LRE. The flow rate ratio for the gas generator and the main chamber was determined to mimic that of real open cycle LRE. Individual component modeling at its transient was completed and was integrated into the system prediction program. Essential parameters of the component dynamic characteristics were examined in an integrated fashion.

• Journal of Internet Computing and Services
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• v.5 no.3
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• pp.87-98
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• 2004

There are several types of distributed subscribers network using Asymmetric Digital Subscriber Line (ADSL), Very high-bit rate Digital Subscriber Line (VDSL), and Data Over Cable Service Interface Specifications (DOCSIS), The efficient and concentrated network management of those several distributed subscribers networks and resources require the general information model of network, which has abstract and conceptional managed objects independent of type of network and its equipment to manage the integrated subscriber network, This paper presents the general Internet subscribers network modeling framework using RM-ODP (Reference Model Open Distributed Processing) to manage that network In the form of integrated hierarchy, This paper adopts the object-oriented development methodology with UML (Unified Modeling Language) and designs and implements the HFC network of DOCSIS as an example of the subscriber network.

• The Journal of Information Systems
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• v.15 no.4
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• pp.125-147
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• 2006

Internet shopping mall has dual nature of information technology features defined by the web-based application system and marketing features explained by the shopping marketplaces. The purpose of this study aims at analyzing the consumer's attempt to purchase and re-purchase intention to the internet shopping mall to combine the IT perspective and the marketing perspective. This paper develop the integrated research model with the acceptance behaviors of customers through consumer's purchase decision process(pre-purchase stage and post-purchase stage). The results from an empirical survey as follows: First, the integrated model is valid in predicting the acceptance of the internet shopping malls by using structured equation modeling. Second, there are the differences between pre-purchase stage and post-purchase stage by each conceptual constructs. Finally, the results of MSEM(Multi-group Structured Equation Modeling) indicate the perceived ease of use and perceived trust to the attitude to the internet shopping mall is more effectively predicted at the pre-purchase stage. Vice versa, the perceived usefulness to the intention to the purchase intention of internet shopping mall is more effectively predicted at the post-purchase stage. This study provides an integrative approach to develop the effective and successful internet shopping mall strategy.