• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1012-1015
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• 1996

This study focuses on the optimal operation and control strategy of the fuel cell process. The control objective of the Phosphoric Acid Fuel Cell (PAFC) is established and dynamic modeling equations of the entire fuel cell process are formulated as discrete-time type. On-line optimal control of the MIMO system employs the direct decomposition-coordination method. The objective function is modified as the tracking form to enhance the response capability to the load change. The weight factor matrices Q,R, which are design parameters, are readjusted. This control system is compared with LQI method and the results show that the suggested method is better than the traditional method in pressure difference control.

• Journal of Korea Multimedia Society
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• v.6 no.5
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• pp.937-944
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• 2003

The most important problems in the multi-agent system are to accomplish a gnat through the efficient coordination of several agents and to prevent collision with other agents. In this paper, we propose a new control strategy for succeeding the goal of a prey pursuit problem efficiently Our control method uses reinforcement learning to control the multi-agent system and consider the distance as well as the space relationship among the agents in the state space of the prey pursuit problem.

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.127-131
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• 2003

• Microbiology and Biotechnology Letters
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• v.47 no.2
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• pp.183-194
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• 2019

The consumption of fresh vegetables has been related to recurrent outbreaks of foodborne diseases (FBD) worldwide. Therefore, the development of effective alternative technologies is necessary to improve the safety of these products. This study aimed to isolate and identify epiphytic lactic acid bacteria (LAB) from fresh fruits and leafy vegetables and characterize their antagonistic capacity due to their ability to produce bacteriocins or antibacterial compounds. For this, 92 LAB isolates from fruits and leafy vegetables were screened for antagonistic activity. Two strains with the highest and broadest antagonistic activities were selected for further characterization; one from cantaloupe melon (strain CM175) and one from cilantro leaves (strain C15). The cell-free supernatants (CFS) of CM175 and C15 were found to exhibit antagonistic activity against FBD-causing pathogens. The CM175 and C15 strains were identified as Pediococcus pentosaceus and Lactobacillus graminis, respectively. Notably, the P. pentosaceus CM175 CFS stopped the growth of Salmonella Typhimurium, Salmonella Saintpaul, Staphylococcus aureus, and Listeria monocytogenes, and delayed Escherichia coli O157:H7 growth. Moreover, L. graminis C15 CFS delayed the growth of all indicator pathogens, but did not completely stop it. Organic acids and bacteriocin-like molecules were determined to be possibly exerting the observed antagonistic activity of the identified LAB strains. Thus, application of the antagonistic compounds produced by Pediococcus pentosaceus and Lactobacillus graminis could be a novel and ecological strategy in developing antimicrobial biopreservatives for the food industry and mitigating FBD by reducing the biological contamination in fruit and vegetable orchards, mainly via their potential in controlling both gram-negative and gram-positive pathogenic bacteria.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.847-858
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• 2015

Control strategy and corresponding parameters have significant impacts on the overall technical and economic characteristics of composite energy storage systems (CESS). A better control strategy and optimized control parameters can be used to improve the economic and technical characteristics of CESS, and determine the maximum power and stored energy capacity of CESS. A novel coordinated control strategy is proposed considering the coordination of various energy storage systems in CESS. To describe the degree of coordination, a new index, i.e. state of charge coordinated response margin of supercapacitor energy storage system, is presented. Based on the proposed control strategy and index, an optimization model was formulated to minimize the total equivalent cost in a given period for two purposes. The one is to obtain optimal control parameters of an existing CESS, and the other is to obtain the integrated optimal results of control parameters, maximum power and stored energy capacity for CESS in a given period. Case studies indicate that the developed index, control strategy and optimization model can be extensively applied to optimize the economic and technical characteristics of CESS. In addition, impacts of control parameters are discussed in detail.

• Proceedings of the KSME Conference
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• 2001.06c
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• pp.380-385
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• 2001

The paper presents a new multidisciplinary design optimization architecture using optimal sensitivity and coordination of interdisciplinary design variables. Original design problem is decomposed into a number of sub-problems that represent individual engineering analysis. The coupled effects between sub-problems are computed by interdisciplinary design variables. System level coordination is determined by optimal parameter sensitivity calculated by finite difference method. The proposed. MDO strategy is applied to a simplified model of rotorcraft blade design associated with structures and aerodynamic disciplines.

• Journal of the Korean Society of Food Culture
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• v.20 no.2
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• pp.261-272
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• 2005

The color and its coordination should intensify the customer's memory and awareness in a brand website, through the consistent communication strategy by which a variety of brand identification in the offline could be expressed efficiently. We evaluated top 5 brand-valuable family restaurants in this study, how they made the best use of the website as a new communication channel, and how they constructed the brand identification by the coloring of a website. We found out that they employed colors with a dynamic and lilting feelings matching the concept of a family restaurant. In addition, A color scheme was well designed for the specific character of a brand, though web-safe colors were seldom employed. This report can be a guide to a corporation for the color and its coordination in the website, when existing brand images need to be intensified and enhanced, or when a new brand image need to be constructed.

• Korean Institute of Interior Design Journal
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• v.19 no.5
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• pp.140-147
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• 2010

The objectives of this study are, first to define the concept of restaurant total coordination and establish its components as a design strategy for planning and managing all elements comprising a restaurant, and second, to survey the total coordination of Japanese restaurants in foreign countries and examine how traditionality, which is an element for globalizing Japanese restaurants, is expressed. This study was conducted through literature review for defining the concept of restaurant total coordination and extracting its components and a field survey for analyzing the current state of restaurant total coordination and traditionality expression methods. The results of this study are as follows. First, Japanese restaurants categorized into Type A with relatively high traditionality expression(3.3 or higher) were 25% of the surveyed restaurants. These restaurants showed the traditional characteristics of Japanese style as they are without contemporary adaptation for all components of restaurant. Second, 41.7% of the restaurants were categorized into Type B with traditionality expression between 1.7 and 3.3. They were mostly popular casual restaurants at which people can enjoy Japanese food comfortably. In visual and spatial design elements, traditional and contemporary styles appeared in the equal percentage, and decoration, table setting and food design were styled according to Japanese traditions. Third, 4 cases(33.3%) were categorized into Type C with traditionality expression below 1.7. Because they were fine dining restaurants that sold high priced dishes, formality and consistency were also high. Through all design elements including visual, spatial, table setting and food design elements, elegant and simple contemporary images were dominant. The results of this study will be used as basic materials to establish the concept of total coordination that views the visual, spatial, table setting and food design elements comprising a restaurant, which were approached separately in previous studies on restaurants, together from the viewpoint of integrative deigns, and to make design strategies for globalizing Korean restaurants based on Japanese restaurant cases.

• Journal of Korea Game Society
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• v.7 no.4
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• pp.93-104
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• 2007

In the complex real-time multi-agent system such as game environment, dynamic task allocations are repeatedly performed to achieve a goal in terms of system efficiency. In this research, we present a task allocation scheme suitable for the real-time multi-agent environment. The scheme is to optimize the task allocation by complementing existing coordination agent with $A^*$ algorithm. The coordination agent creates a status graph that consists of nodes which represent the combinations of tasks and agents, and refines the graph to remove nodes of non-execution tasks and agents. The coordination agent performs the selective utilization of the $A^*$ algorithm method and the greedy method for real-time re-allocation. Then it finds some paths of the minimum cost as optimized results by using $A^*$ algorithm. Our experiments show that the coordination agent with $A^*$ algorithm improves a task allocation efficiency about 25% highly than the coordination agent only with greedy algorithm.

• Journal of Korea Technology Innovation Society
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• v.18 no.1
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• pp.1-27
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• 2015

Korea has increased R&D investment continuously for the improvement of global technological competencies. Korea ranked first in the world with 4.15 percent in the ratio of R&D investment to GDP. In particular, the private sector occupies a crucial position of technological innovations in Korea, constituting 78.5% of total R&D investment. However, quantitative growth strategy is no longer effective, so efforts to enhance efficiency by upgrading qualitative level are badly needed. This paper studied methods for improving firms' business performance. For this, it tried to empirically verify technology strategy and technology planning capability's influence factors on the improvement of business performance. The study showed that technology strategy and technology planning activities have positive effects on the improvement of business performance. And it was revealed that coordination flexibility contributes to the enhancement of business performance by positively controlling technology planning activities. The study performed sample survey on the companies with R&D centers and multiple regression analysis and quantile regression were used for the analysis.