• 한국소음진동공학회논문집
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• 제19권4호
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• pp.355-362
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• 2009

Sound source localization method based on the time delay of arrival(TDOA) is applied to many research fields such as a robot auditory system, teleconferencing and so on. When multi-microphones are utilized to localize the source in 3 dimensional space, the conventional localization methods based on TDOA decide the actual source position using the TDOAs from all microphone arrays and the detection measure, which represents the errors between the actual source position and the estimated ones. Performance of these methods usually depends on the number of microphones because it determines the resolution of an estimated position. In this paper, we proposed the localization method using spatially mapped GCC functions. The proposed method does not use just TDOA for localization such as previous ones but it uses spatially mapped GCC functions which is the cross correlation function mapped by an appropriate mapping function over the spatial coordinate. A number of the spatially mapped GCC functions are summed to a single function over the global coordinate and then the actual source position is determined based on the summed GCC function. Performance of the proposed method for the noise effect and estimation resolution is verified with the real environmental experiment. The mean value of estimation error of the proposed method is much smaller than the one based on the conventional ones and the percentage of correct estimation is improved by 30% when the error bound is ${\pm}20^{\circ}$.

• Journal of Ginseng Research
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• 제43권3호
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• pp.421-430
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• 2019

Background: The ginsenoside Rg3, one of active components of red ginseng, has chemopreventive and anticancer potential. Cancer stem cells retain self-renewal properties which account for cancer recurrence and resistance to anticancer therapy. In our present study, we investigated whether the standardized Korean Red Ginseng extract (RGE) and Rg3 could modulate the manifestation of breast cancer stem cell-like features through regulation of self-renewal activity. Methods: The effects of RGE and Rg3 on the proportion of $CD44^{high}/CD24^{low}$ cells, as representative characteristics of stem-like breast cancer cells, were determined by flow cytometry. The mammosphere formation assay was performed to assess self-renewal capacities of breast cancer cells. Aldehyde dehydrogenase activity of MCF-7 mammospheres was measured by the ALDEFLUOR assay. The expression levels of Sox-2, Bmi-1, and P-Akt and the nuclear localization of hypoxia inducible $factor-1{\alpha}$ in MCF-7 mammospheres were verified by immunoblot analysis. Results: Both RGE and Rg3 decreased the viability of breast cancer cells and significantly reduced the populations of $CD44^{high}/CD24^{low}$ in MDA-MB-231 cells. RGE and Rg3 treatment attenuated the expression of Sox-2 and Bmi-1 by inhibiting the nuclear localization of hypoxia inducible $factor-1{\alpha}$ in MCF-7 mammospheres. Suppression of the manifestation of breast cancer stem cell-like properties by Rg3 was mediated through the blockade of Akt-mediated self-renewal signaling. Conclusion: This study suggests that Rg3 has a therapeutic potential targeting breast cancer stem cells.

• 한국군사과학기술학회지
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• 제15권3호
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• pp.298-305
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• 2012

In this paper, we propose an integrated algorithm for scene recognition, which has been a challenging computer vision problem, with application to mobile robot localization. The proposed scene recognition method utilizes SIFT and visual words as local-level features and GIST as a global-level feature. As local-level and global-level features complement each other, it results in improved performance for scene recognition. This improved algorithm is of low computational complexity and robust to image distortions.

• 제어로봇시스템학회논문지
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• 제14권5호
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• pp.483-488
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• 2008

An active omni-directional raging system using an omni-directional vision with structured light has many advantages compared to the conventional ranging systems: robustness against external illumination noise because of the laser structured light and computational efficiency because of one shot image containing $360^{\circ}$ environment information from the omni-directional vision. The omni-directional range data represents a local distance map at a certain position in the workspace. In this paper, we propose a matching algorithm for the local distance map with the given global map database, thereby to localize a mobile robot in the global workspace. Since the global map database consists of line segments representing edges of environment object in general, the matching algorithm is based on relative position and orientation of line segments in the local map and the global map. The effectiveness of the proposed omni-directional ranging system and the matching are verified through experiments.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1381-1382
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• 2015

본 논문에서는 초음파 수신기 어레이 및 아날로그 신호처리부로 구성된 스트랩다운 측위센서를 이용하여 특정 위치에 장착되어 있는 송신기와 로봇 간 상대위치를 측정할 수 있는 새로운 형태의 자율주행로봇 보조항법 시스템을 제안한다. 이를 이용하여 상태변수 간의 기하학적 상관관계를 활용하여 십자형으로 배열된 다중센서 기반 피동 위치추정 필터 구현에 사용되는 설계변수의 불완전성을 보상하는 방법을 제안한다. 모의실험을 통해 제안한 방법의 유용성을 검증한다.

• 대한임베디드공학회논문지
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• 제16권6호
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• pp.293-297
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• 2021

This paper presents how to create a 3D map and solve problems related to generating a global path planning for navigation. Map creation and localization were performed using the RTAB-Map package to create a 3D map of the environment. In addition, when the target point is within the obstacle space, the problem of not generating a global path was solved using the asr_navfn package. The performance of the proposed system is validated through experiments with a wheelchair-type robot.

• 한국프랜차이즈경영연구
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• 제13권2호
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• pp.1-15
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• 2022

Purpose: The globalization of the Korean restaurant franchise industry differs from the business performance of enhancing the brand image and customers' intention to revisit depending on the degree of localization marketing. Therefore, it is necessary to consider the extent to which the localization marketing activities of overseas Korean restaurant franchise companies affect the customer's perception. This study aims to investigate the effects of localization marketing (Localized Menu, Localized Price, Localized Service Experience, Localized Promotion, Localized Physical Environment) of Korean restaurant franchise companies on customer revisit intention. Research design, data, and methodology: For this study, 150 questionnaires using local Korean restaurants in Beijing, China, were analyzed using SPSS Ver.21 and AMOS Ver.22. Result: It was confirmed that the localized menu, localized service experience, and localized physical environment all affect the intention to revisit customers. Based on these verification results, if overseas franchises fully recognize localization marketing, which is an important factor for local business success, and establish localization strategies, they can gain an edge in competition with local Korean restaurants or restaurant franchises founded by locals. There may be a higher probability that However, it was found that localization price and localization promotion had no mediating effect of brand image between revisit intention and revisit intention. It was found that it had no effect on the degree of inquiry and had a negative effect. Conclusions: Due to the impact of the COVID-19 pandemic, there have been many changes in the domestic and overseas food service industry over the past two years. Therefore, in future research, it is necessary to study the localization of overseas Korean restaurant franchise companies that are more multidimensionally subdivided. Various measures of customized localization marketing for optimal regional characteristics should be developed and applied to enhance customer revisiting and brand image of Korean restaurant franchise companies entering overseas. In the future, this study will be meaningful data for the establishment of localization marketing (Localized Menu, Localized Price, Localized Service Experience, Localized Promotion, Localized Physical Environment) strategies for Korean restaurant franchise companies that consider overseas expansion or have already entered.

• The Journal of Asian Finance, Economics and Business
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• 제7권1호
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• pp.205-215
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• 2020

The purpose of this paper is to empirically analyze the determinants of foreign subsidiary's local embeddedness because it is critically important for the subsidiary to build a variegated local network. This paper suggests that a MNC's global capability, the degree of autonomy granted by the headquarters of the multinational corporation to its foreign subsidiary, the foreign subsidiary's absorptive capacity based on local environment, and its level of localization will affect the subsidiary's local network embeddedness. The empirical analysis confirmed that when the headquarters gives the foreign subsidiary more autonomy, this has a positive effect on the local embeddedness of the foreign subsidiary and when the foreign subsidiary has a strong absorptive capacity, this has a positive correlation with the local embeddedness of the foreign subsidiary. And this paper found that when the foreign subsidiary has achieved a high level of staff localization, this foreign subsidiary will have a higher level of local embeddedness. This study identified the preceding conditions necessary for a foreign subsidiary of a multinational corporation to effectively embed itself in the local network by analyzing factors related to the multinational corporation's headquarters and subsidiaries, and thus contributes significantly to continued research on the local embeddedness of subsidiaries.

• 동아시아경상학회지
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• 제9권1호
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• pp.53-61
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• 2021

Purpose - This study aims to understand the phenomenon called "regional multinational" in the geographical expansion of multinational enterprises and to find some evidence whether globalization of multinational enterprises tends to have a strong home region bias. Research design, data, and methodology - Through an in-depth case analysis, we analyze the series of strategic behaviors Wal-Mart made in South Korea from its entry in 1998 to its withdrawal in 2006. Then, we discuss the plausible causes of this exit, seeking to provide some evidence on the "regional multinational" phenomenon. Result - This study finds some evidence on the regional-based expansion of multinational enterprises. Our case study shows that Wal-Mart in South Korea focused on global standardization strategy and made an exit from the market as they were faced with increasing localization demands. From the perspective of multinational enterprises' globalization strategy, Wal-Mart's exit from the South Korean market can be considered as a strategic exit. Conclusion - The findings of this study suggest that while national responsiveness and localized adaptation are considered as a panacea for penetrating international markets, in reality most multinational enterprises attempt to add value primarily by capitalizing on similarities across markets and remain as regional multinationals.

• 정보처리학회논문지D
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• 제12D권3호
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• pp.481-492
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• 2005

시각 장애인용 유도 로봇을 안전하게 유도하기 위해서는 경로를 검색하기 위해 사용되는 전자지도가 섬세해야 하며 위험한 위치에 대한 정보를 가지고 있어야 한다. 또한 GPS와 INS에 의해 획득한 위치정보를 통하여 안전하면서도 빠른 최단 경로를 검색해야 한다. 본 논문에서는 시각 장애인의 인식 능력의 차이에 따라 시각 장애인에게 경로의 안내 및 위치정보만을 제공하는 이동경로 생성 및 확인을 위한 자기 위치 추적 시스템과 주변 환경정보인식 및 GPS 오차보정기능을 가진 유도로봇과 통합된 시각장애인용 전역항법시스템을 구현하였다. 이 시스템을 통하여 시각 장애인이 비교적 짧은 거리를 이동하고자 할 때 활용할 수 있으며, 실외 환경에서는 GPS의 보조 항법 시스템으로 위치의 보정을 할 수 있음을 알 수 있었다.