• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.2
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• pp.1-9
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• 2014

A modeling system is constructed by integrating an one-dimensional unsteady flow simulation model and a hydrologic model to simulate flood flows in drainage channel networks of paddy field districts. The modeling system's applicability is validated by simulating flood discharges from a paddy field district, which consists of nine paddy fields and one drainage channel. The simulation results are in good agreement with the observed. Particularly, in the verification stage, the relative errors of peak flows and peak depths between the observed and simulated hydrographs range 8.96 to 10.26 % and -10.26 to 2.97 %, respectively. The modeling system's capability is compared with that of a water balance equation-based model; it is revealed that the modeling system's accuracy is superior to the other model. In addition, the simulations of flood discharges from large-sized paddy fields through drainage channels show that the flood discharge patterns are affected by drainage outlet management for paddy fields and physical characteristics of the drainage channels. Finally, it is concluded that to efficiently design drainage channel networks, it is necessary to analyze the results from simulating flood discharges of the drainage channel networks according to their physical characteristics and connectivities.

• Journal of Korea Society of Digital Industry and Information Management
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• v.5 no.3
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• pp.99-105
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• 2009

This paper suggests novel signal processing methods for optimal beamforming of smart antenna system in CDMA2000 mobile communication environments. This method utilize characteristics of the reverse pilot channel of CDMA2000 mobile communication systems, and applies them to improve the performance of an adaptive algorithm, which is used to a smart antenna system for beamforming. To perform the best beamforming, it is important to get an exact beamforming algorithm. This paper proposed an algorithm based on Laglange multiplier which has such an adaptive process, and also proposed the method to demodulate the received signal through array antenna using pilot channel in CDMA2000 environment. This paper analysed the enhanced performance of proposed algorithm in various signal environment through signal modeling of physical layer in CDMA2000 reverse link.

• Korean Management Science Review
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• v.22 no.1
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• pp.149-165
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• 2005

From the growth of internet technology, many e-commerce principles have been Introduced In airline industry. The computer reservation systems(CRS) has been considered as the first real-time business application and the earliest examples of e-commerce. in airlines, the early e-business activity was to build the web site for providing flight Information to customers. Recently, many airlines are expanding the capability of the web site for selling tickets on the web to make use of the cheaper distribution channel. In this paper, we focus on the impacts of airline e-business being implemented in airline distribution channels. Using the conjoint analysis, we suggest a model for estimating the change of market sales for each distribution channel. With the empirical survey, we can find some implications on the e-business strategy and the effective internet marketing tools for airlines.

• Korean Management Science Review
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• v.17 no.3
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• pp.49-60
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• 2000

The proliferation of electronic commerce(EC) has led manufactureres to consider Internet based marketing as a salient candidate for strategic diversification of marketing channel. In this case, each manufacturer can build its own Web store or rent an existing special EC store. Such decision making of ‘build’ or ‘rent’ can be analyzed by a game model which derives the Nash solutions for price and profit considering degree of competition with other competitive manufacturers. In this paper, to overcome the drawbacks of the traditional linear demand function, we first propose a new linear demand function which incorporates not only the price difference between competitive products but the awareness of Web stores perceived by the consumers, then design the game models to analyze the characteristics of three typical types of marketing channel in duopoly market. Based on the Nash solutions of the game models, we analyzed the effect of the degree of competition and Web awareness in selecting the optimal marketing channel.

• Korean Management Science Review
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• v.17 no.3
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• pp.73-95
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• 2000

In Korea, the distribution channel for agricultural products is notorious for its complexity and ineffectiveness. In this sense, the Agricultural Cooperative has tried to clarify the distribution channel and reduce its length. However, there still exist much room for improvements. The Internet shopping mall specific for agricultural product, therefore, is drawing much attention because it can reduce the length of distribution channel drastically and improve effectiveness from the distribution perspective. To test the validity of such Internet-driven shopping mall, we gathered questionnaire data from the Internet based Hannaro Shopping Mall which is run directly by the Agricultural Cooperative. We performed experiments respectively for the two groups of operating personnel and consumers. Experimental results showed that several important factors can be identified which are significant statistically and deemed to have meaningful relationship with performance variables. Our results also showed that the Internet shopping mall has a great potential for improving the effectiveness of the distribution channel of the agricultural products.

• Journal of Communications and Networks
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• v.10 no.1
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• pp.38-43
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• 2008

In this paper, adaptive channel borrowing approach fuzzy neural networks for load balancing (ACB-FNN) is presented to maximized the number of served calls and the depending on asymmetries traffic load problem. In a wireless network, the call's arrival rate, the call duration and the communication overhead between the base station and the mobile switch center are vague and uncertain. A new load balancing algorithm with cell involved negotiation is also presented in this paper. The ACB-FNN exhibits better learning abilities, optimization abilities, robustness, and fault-tolerant capability thus yielding better performance compared with other algorithms. It aims to efficiently satisfy their diverse quality-of-service (QoS) requirements. The results show that our algorithm has lower blocking rate, lower dropping rate, less update overhead, and shorter channel acquisition delay than previous methods.

• Journal of Korea Society of Digital Industry and Information Management
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• v.4 no.1
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• pp.1-8
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• 2008

In the Web 2.0, besides more gaining information on the web, the number of web sites that take advantage of RSS increases explosively. Commonly each users search RSS channels through the web search engine before registering RSS channel's url to the RSS reader. Users judge whether the site is RSS channel or not and register an RSS channel's url through theirs interests. Because accomplished by users themselves, those processes conflict to user's convenience and quick consumption of information. Techniques of current search engines can't provide users with reliable RSS feed information as search results. In this paper, we analysis appropriateness of current search engines' techniques that offer users RSS feed search service and discuss their limitations. Also, we make up RSS feed database through classification of RSS tag being possible to search RSS feed information effectively and apply update rate of each RSS channel's feed to ranking algorithm providing more reliable search results.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.10a
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• pp.99-115
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• 2004

From the growth of Internet technology, many e-commerce principles have been introduced in airline industry. The computer reservation systems(CRS) is the first real-time business application and considered as the earliest examples of e-commerce. In airlines, the early e-business activity was to build the web site for providing flight information to customers. Recently, many airlines are expanding the capability of the web site for selling tickets on the web to make use of the cheaper distribution channel. In this paper, we focus on the impacts of airline e-business being implemented in airline distribution channels. Using the conjoint analysis, we suggest a model for estimating the change of market sales for each distribution channel. With the empirical survey, we can find some implications on the e-business strategy and the effective internet marketing tools for airlines.

• Management Science and Financial Engineering
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• v.13 no.1
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• pp.55-72
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• 2007

We consider the product differentiation model of online channel competition and examine the strategies of hybrid firms in terms of efficiency. After measuring the social cost of online business strategies, we show that (i) online channel of hybrid firm under blockaded entry may increase the social cost if the firms' delivery cost is sufficiently smaller than the consumer's transportation cost, and (ii) online competition under free entry may increase the social cost if the firms' delivery cost is sufficiently larger than the consumer's transportation cost. Finally, we discuss the strategic incentive of hybrid firms to reduce delivery cost and investigate the effect of the Internet maturity on the social cost.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.304-309
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• 2015

On construction sites, it is important to monitor the performance of construction equipment and workers to achieve successful construction project management; especially, vision-based detection methods have advantages for the real-time site data collection for safety and productivity analyses. Although many researchers developed vision-based detection methods with acceptable performance, there are still limitations to be addressed: 1) sensitiveness to the shape and appearance changes of moving objects in difference working postures, and 2) high computation time. To deal with the limitations, this paper proposes a detection algorithm of construction equipment based on Integral Channel Features. For validation, 16,850 frames of video streams were recorded and analyzed. The results showed that the proposed method worked in high performance in terms of accuracy and processing time. In conclusion, the developed method can help to understand useful site information including working pattern, working time and input manpower analyses.