• Journal of Communications and Networks
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• v.5 no.3
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• pp.266-274
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• 2003

One of the major issues in current on-demand routing protocols for ad hoc networks is the high resource consumed by route discovery traffic. In these protocols, flooding is typically used by the source to broadcast a route request (RREQ) packet in search of a route to the destination. Such network-wide flooding potentially disturbs many nodes unnecessarily by querying more nodes than is actually necessary, leading to rapid exhaustion of valuable network resources such as wireless bandwidth and battery power. In this paper, a simple optimization technique for efficient route discovery is proposed. The technique proposed herein is location-based and can be used in conjunction with the existing Location-Aided Routing (LAR) scheme to further reduce the route discovery overhead. A unique feature of our technique not found in LAR and most other protocols is the selective use of unicast instead of broadcast for route request/query transmission made possible by a novel reuse of routing and location information. We refer to this new optimization as the UNIQUE (UNIcast QUEry) technique. This paper studies the efficacy of UNIQUE by applying it to the route discovery of the Dynamic Source Routing (DSR) protocol. In addition, a comparative study is made with a DSR protocol optimized with only LAR. The results show that UNIQUE could further reduce the overall routing overhead by as much as 58% under highly mobile conditions. With less congestion caused by routing traffic, the data packet delivery performance also improves in terms of end-to-end delay and the number of data packets successfully delivered to their destinations.

• Journal of Korea Society of Industrial Information Systems
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• v.28 no.1
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• pp.35-48
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• 2023

In this study, we introduced the development status and the government policy of the Chinese automobile industry under the rapidly changing global economic environment. We conducted a consumer trend survey on automobile purchases by consumers in China. Despite the Chinese government's strong national emission control policy and stricter standards for manufacturing and selling internal combustion engine vehicles, 59.6% of respondents saying they would choose an internal combustion engine vehicle when purchasing a vehicle in the future for various reasons. It was confirmed that there is a significant gap between government policies and consumer perceptions. In addition, we have discovered the recent declining trend of automobile sales in China, and used the monthly sales volume from January 2010 to December 2020 as training set, and the sales volume from January 2021 to November 2022 as a test set. We proposed and evaluated a time-series model for predicting future automobile demand in China. Then, we showed the monthly sales forecast for 2023 when each model was applied.

• Journal of the Society of Naval Architects of Korea
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• v.54 no.4
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• pp.344-351
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• 2017

CAD systems used in various manufacturing industries have been rapidly switched from 2D to 3D. 3D-based design is becoming common in the shipbuilding industries too. However, there is still a demand for 2D drawings for ship production. So, it is necessary to continually improve 2D drawings. One way to improve 2D drawings is to add production information to the drawings. To do this, it is necessary to define the relation between the geometry information and the production information. Various types of drawings, which is inevitable because each drawing has its own purpose, make it difficult to define relations. This process can be simplified if the drawing information is neutralized. XML is a standard format for defining neutral data, and is already being used in various fields. In this study, a neutral augmented drawing has been defined by neutralizing the drawing information based on XML, and implemented for the allocation of their information with high quality of readability as well.

• Journal of the Korean housing association
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• v.15 no.6
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• pp.115-125
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• 2004

This research is inquired to the residents in Kimcheon, Kyongsang-Boukdo and in Kangnung, Yangyang, Kangwon-Do. The residents were damaged by typhoon ${\ulcorner}RUSA{\lrcorner}$ in 2002, which occurred the biggest damage in our country's natural disaster. The result of inquiry is arranged in this research. Inquiry contents arrange a current events points through the inquiry. which is about the resident's demand and confrontation caused by a big disaster occurrence; the damage present condition which is caused by typhoon ${\ulcorner}RUSA{\lrcorner},$ the countermeasure condition on damage occurrence, the necessity content of area disaster information, the difficulty factor of damage restoration, the evaluation of the government and relation group's countermeasure which is about typhoon ${\ulcorner}RUSA{\lrcorner},$ the mental and body problem after disaster occurrence. And inquiry contents present the fundamental data for establishing the area prevention of disaster plan hereafter.

• Journal of Intelligence and Information Systems
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• v.19 no.1
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• pp.35-55
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• 2013

Information technology is a critical resource necessary for any company hoping to support and realize its strategic goals, which contribute to growth promotion and sustainable development. The selection of information technology and its strategic use are imperative for the enhanced performance of every aspect of company management, leading a wide range of companies to have invested continuously in information technology. Despite researchers, managers, and policy makers' keen interest in how information technology contributes to organizational performance, there is uncertainty and debate about the result of information technology investment. In other words, researchers and managers cannot easily identify the independent factors that can impact the investment performance of information technology. This is mainly owing to the fact that many factors, ranging from the internal components of a company, strategies, and external customers, are interconnected with the investment performance of information technology. Using an agent-based simulation technique, this research extracts factors expected to affect investment performance on information technology, simplifies the analyses of their relationship with economic modeling, and examines the performance dependent on changes in the factors. In terms of economic modeling, I expand the model that highlights the way in which product quality moderates the relationship between information technology investments and economic performance (Thatcher and Pingry, 2004) by considering the cost of information technology investment and the demand creation resulting from product quality enhancement. For quality enhancement and its consequences for demand creation, I apply the concept of information quality and decision-maker quality (Raghunathan, 1999). This concept implies that the investment on information technology improves the quality of information, which, in turn, improves decision quality and performance, thus enhancing the level of product or service quality. Additionally, I consider the effect of word of mouth among consumers, which creates new demand for a product or service through the information diffusion effect. This demand creation is analyzed with an agent-based simulation model that is widely used for network analyses. Results show that the investment on information technology enhances the quality of a company's product or service, which indirectly affects the economic performance of that company, particularly with regard to factors such as consumer surplus, company profit, and company productivity. Specifically, when a company makes its initial investment in information technology, the resultant increase in the quality of a company's product or service immediately has a positive effect on consumer surplus, but the investment cost has a negative effect on company productivity and profit. As time goes by, the enhancement of the quality of that company's product or service creates new consumer demand through the information diffusion effect. Finally, the new demand positively affects the company's profit and productivity. In terms of the investment strategy for information technology, this study's results also reveal that the selection of information technology needs to be based on analysis of service and the network effect of customers, and demonstrate that information technology implementation should fit into the company's business strategy. Specifically, if a company seeks the short-term enhancement of company performance, it needs to have a one-shot strategy (making a large investment at one time). On the other hand, if a company seeks a long-term sustainable profit structure, it needs to have a split strategy (making several small investments at different times). The findings from this study make several contributions to the literature. In terms of methodology, the study integrates both economic modeling and simulation technique in order to overcome the limitations of each methodology. It also indicates the mediating effect of product quality on the relationship between information technology and the performance of a company. Finally, it analyzes the effect of information technology investment strategies and information diffusion among consumers on the investment performance of information technology.

• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.233-236
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• 2004

With the internet(World Wide Web) widespread among people after 1995, Information Communication Network, which is basic structure of the internet, is rapidly changing into fiber optics communication. The information conveyed through the internet is being diversified - from simple information based on text to bulky multimedia information such as auido & video data. So the demand for higher speed, hish storage Router is on the crease. This research aims to analyze the general trend of the patent by systematical, multilateral and segmented analysis of the technology's flow and trend, the present technological position of status and the distribution map of the technology by country, technology area using chart and graph.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.11a
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• pp.342-345
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• 2003

Due to the rapid development of manufacturing and information technology, traditional supply chain scheme has been changed dramatically Most companies have been forced to relocate or redesign their logistics network in different countries. A supply chain partnership is a relationship formed between two independent members in supply chain through information sharing to achieve specific objectives and benefits in terms of reductions in total costs and inventories. This study illustrates the benefits of supply chain partnerships based on information sharing and lead-time patterns. We consider three level of information sharing: (1) immediate order information; (2) demand information; (3) inventory information. Given a fixed total lead-time, how lead-time distribution will affect the bullwhip effect and inventory cost under information sharing strategies. The results can help improving supply chain performance and selecting suitable direction for the re-configuration of supply chain network.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.1
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• pp.1-9
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• 2017

With the Development of Wireless Network Technology and Wireless Link Technology, Wireless Mesh Network (WMN) is Attracting Attention as a Key Technology to Construct the Wireless Transit Network. The WMN has been Studied for a Long Time in Various Fields, however there are still many Problems that have not been solved yet. One of them is the Routing Problem to find an Optimal path in a Multi-hop Network Composed of Wireless Links. In the Hybrid-WMN, which is one of the Three Types of WMN, Optimal Path Selection Requires Research on Path Search Protocols that Effectively use the Infrastructure Mesh as a Transit Network, Together with Research for a Routing Metric with Excellent Performance. Therefore, this Paper Proposes a Dual Mode-AODV(Ad hoc On-demand Distance Vector) for Hybrid-WMN. Simulation result shows that the Path Selection Delay was Reduced by 52% than AODV when the Proposed Dual Mode-AODV was applied.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.1
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• pp.11-19
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• 2012

Due to existing infrastructure to collect traffic information was constructed to expressway and national highway, we cannot precisely know traffic situation for their surrounding area. Therefore, it is difficult to provide reliable traffic information to users using navigation and smartphone. In this research, we collected aerial images by using unmanned airship capable of wide-area monitoring and proposed a method extracting vehicle speed from the collected data. And, we performed experiments to verify the accuracy of extracted vehicle speed. Our method proposed in this research can be used to extract a new approach of traffic information according to increased demand of traffic monitoring. We expect that our method will become a new research trend in traffic information application.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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• pp.163-166
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• 2003

Hull form designers have to design a ship with satisfying an economical, technical and environmental demand. When it is concerned by a technical and environmental demand, there will be a economical demand left to criticize optimization. In this case, there were used to be requirements which needs to meet only a best performance not concerning about input of Human resource. Life cycle's cost contains building cost and operation cost so that now we need to check Man Hour cost in building a ship. This research shows a correlation between hull form information, i.e. curvature, length, breadth and thickness of surface and Man Hour of the Shell plating manufacture with using Artificial Neural Network and Gentic Programming. This study will support to classify initial work, to have a high assumption possible through predicting a Man Hour and to provide a guide book to infer a building cost and a economical optimization hull form.