• Journal of the Society of Naval Architects of Korea
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• v.48 no.3
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• pp.215-221
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• 2011

To improve the naval ship acquisition process, systems engineering, modeling and simulation, etc. have been introduced, and there has been ongoing research on acquisition systems for effective support of it. However, due to characteristics of the naval ship acquisition process, development process mainly carried out at a shipyard such as basic design, detailed design, construction and test is difficult to integrate with the acquisition systems of IPT(Integrated Project Team). In addition, research aimed to improve this is rather lacking. In this paper, the naval ship product structure concept proposed in previous research was applied to the basic design system at shipyard, and basic research for expanding the coverage of naval ship acquisition systems to the basic design phase is performed. A data structure of modeling system appropriate to the basic design phase was proposed through research findings and the prototype system based on it was implemented.

• 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.

• Korean Journal of Computational Design and Engineering
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• v.11 no.4
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• pp.273-288
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• 2006

Information integration of heterogeneous digital parts libraries or electronic pars catalogs is one of issues in B2B procurements. We need to provide an integrated view for multiple information sources. Utilization of ontologies as the metadata descriptions of the information sources can provide an integrated view. However, in order to integrate independently developed ontologies, the mismatches among them should be resolved. In this paper, we propose an ontology of meta-concepts, i.e. meta-ontology. The meta-concepts play the role of vocabulary to describe the parts library ontologies and provide well-established ontological semantics that helps the ontology modelers to consistently identify parts library concepts and systematically structure them. Consequently, the meta-ontology reduces the differences in the way the parts knowledge is interpreted and ensures the mismatches are confined to manageable mis matches, so that a software program can merge automatically. Modeling ontologies of mold and die parts libraries for B2B e-commerce is taken as an example to show how to use the meta-ontology. We also discuss how a parts library mediation system can automatically merge the well-structured parts library ontologies.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.3
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• pp.222-235
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• 2018

The hydrocarbon gas leak in the offshore plant can cause large accidents and lead to significant damages to human, property and environment. For prevention of fire or explosion accidents from gas leak, a SIS(Safety Instrumented System) should be installed. In the early stage of the offshore design, required SIL(Safety Integrated Level) is determined and reliability analysis is performed to verify the design in reliability aspects. This study collected data, information related to reliability analysis and created knowledge model of safety design for the offshore system with MBSE(Model-Based Systems Engineering) concept. Knowledge model could support safety engineer's design tasks as the guidance of reliability analysis procedure of safety design and make good conversation with other engineers in yard, class, company, etc.

• Journal of Korean Society for Quality Management
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• v.30 no.4
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• pp.58-67
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• 2002

Since the inception of off-line quality control, it has drawn a particular attention from research community and it has been implemented in a wide variety of industries mainly due to its extensive applicability to numerous real situations. Emphasizing design issues rather than control issues related to manufacturing processes, off-line quality control has been recognized as a cost-effective approach to quality improvement. It mainly consists of three design stages: system design, parameter design, and tolerance design which are implemented in a sequential manner. Utilizing experimental designs and optimization techniques, off-line quality control is aimed at achieving product performance insensitive to external noises by reducing process variability. In spite of its conceptual soundness and practical significance, however, off-line quality control has also been criticized to a great extent due to its heuristic nature of investigation. In addition, it has also been pointed out that the process optimization procedures are inefficient. To enhance the current practice of off-line quality control, this study proposes an integrated optimization model by utilizing a well-established statistical tool, so called response surface methodology (RSM), and a tolerance - cost relationship.

• International Journal of Computer Science & Network Security
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• v.21 no.12
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• pp.9-20
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• 2021

Abstraction applied in computer networking hides network details behind a well-defined representation by building a model that captures an essential aspect of the network system. Two current methods of representation are available, one based on graph theory, where a network node is reduced to a point in a graph, and the other the use of non-methodological iconic depictions such as human heads, walls, towers or computer racks. In this paper, we adopt an abstract representation methodology, the thinging machine (TM), proposed in software engineering to model computer networks. TM defines a single coherent network architecture and topology that is constituted from only five generic actions with two types of arrows. Without loss of generality, this paper applies TM to model the area of network monitoring in packet-mode transmission. Complex network documents are difficult to maintain and are not guaranteed to mirror actual situations. Network monitoring is constant monitoring for and alerting of malfunctions, failures, stoppages or suspicious activities in a network system. Current monitoring systems are built on ad hoc descriptions that lack systemization. The TM model of monitoring presents a theoretical foundation integrated with events and behavior descriptions. To investigate TM modeling's feasibility, we apply it to an existing computer network in a Kuwaiti enterprise to create an integrated network system that includes hardware, software and communication facilities. The final specifications point to TM modeling's viability in the computer networking field.

• KEPCO Journal on Electric Power and Energy
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• v.7 no.2
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• pp.249-254
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• 2021

As the spreading speed of electric vehicles increases rapidly, those are expected to be able to use them as flexible resources in the power system beyond the concern for the supply of its charging power. Especially when the Renewable Energy sources (RES) which have no intrinsic control capability have replaced the synchronous generators more and more, the power system needs to secure the additional frequency control resources to ensure its stability. However, the feasibility of using electric vehicles as the frequency control resources should be analyzed from the perspective of the power system operation and it requires the existing simulation frameworks for the power system. Therefore, this paper proposes the grid connected modeling of the primary frequency control provided by electric vehicles which can be integrated into the existing power system model. In addition, the proposed model is implemented considering technical performances constrained by the characteristics of the Vehicle-Grid Integration (VGI) system so that the simulation results can be accepted by the power utilities operating the power system conservatively.

• Geophysics and Geophysical Exploration
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• v.16 no.4
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• pp.257-267
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• 2013

3-D ore modeling was performed to understand the configuration of ore bodies by integrated analysis of borehole and geophysical data in iron-mine area. Five representative indices of rocks were designated, which were obtained from geological survey and borehole. The five indices of rocks were geostatistically simulated by Sequential Indicator Simulation method to delineate boundary of the ore bodies. And Ordinary Kriging and Sequential Gaussian Simulation was applied to make secondary information using resistivity data from magnetotellurics and DC resistivity survey, and this information was used for simple kriging with local varying means, one of integrated kriging techniques. From the correlation analysis between each properties, it was found that high grade of ore is characterized by increased density, whereas the electrical resistivity decreases. With the integrated results of geophysical and borehole data, it was also found that the real configuration of ore body was similar to the modeled result and information about ore grade in 3-D space was obtained.

• Journal of Wetlands Research
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• v.23 no.1
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• pp.67-73
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• 2021

As the impermeable area increases due to urbanization and industrialization, the influence of non-point pollutants caused by rainfall runoff on the water system is increasing. In the past, the best management practices(BMP) were used a lot to manage non-point pollutants, but recently, technology that naturally treats them through LID (Low Impact Development) technology is widely used. In this study, various rainfall events were simulated through the SWMM model based on the data of rainfall monitoring in bioretention among natural facilities. The characteristic of LID modeling research is that it is difficult to build accurate modeling data with short-term data because real data is the result obtained through natural facilities, and it is difficult to implement an accurate model. In this study, the data monitored for 3 years It is significant in that it has built a precise model. The actual data monitored a total of 18 times was simulated, and the inflow and outflow and the removal efficiency of five pollutants were simulated. As a result of performing the performance evaluation, most of the 7 items showed excellent indicators, and the TN and TP showed relatively low simulation performance. In the future, it is expected that Korea will introduce an integrated water management system in which the water supply system and the sewage system are substantially integrated and operated. Therefore, the results of this study are considered to play an important role in the initial stage of rainfall management in the future integrated water management system, and the extent of rainfall runoff reduction and pollutant reduction in the expected installation area can be predicted in advance. This is expected to prevent overdesign of bioretention.

• Geophysics and Geophysical Exploration
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• v.4 no.1
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• pp.1-7
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• 2001

The application of geophysical survey methods need to be integrated to meet the increasing demands of imaging of the subsurface in the practical application of civil engineering, underground water survey and environmental problems. This paper examines the IP survey which can be surveyed simultaneously with DC resistivity survey. In this study, 3-D IP modeling algorithm was developed. The 3-D IP modeling algorithm was based on 3-D resistivity modeling by finite-element method. The result of 3-D modeling was compared with 2-dimensional modeling result. The result showed that the 3-D modeling algorithm developed in this study was accurate. Finally, the 3-D modeling algorithm developed in this paper will be useful for the study of IP data.