• Journal of Korea Trade
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• 제24권1호
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• pp.82-98
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• 2020

Purpose - This study aims to overcome the limitations of existing studies, which linearly determine the precedence factors of competency in overseas subsidiaries. The research objectives are as follows. First, what kind of nonlinear effects does the level of control held by Korean headquarters over foreign subsidiaries have in terms of competency in the subsidiaries? Second, what kind of nonlinear effects do the local experiences of overseas subsidiaries have on their competency? Design/methodology - With data on Korean multinational corporations (MNCs), this paper analyzes the effects of control levels of headquarters (HQs) and host-country experiences of foreign subsidiaries regarding competency in overseas subsidiaries. In particular, this study focuses on nonlinear models, differentiating it from previous studies. In order to examine research hypotheses, this study conducted a survey of overseas subsidiaries of Korean corporations. Surveys were conducted through various methods including e-mail, online questionnaires, fax, and telephone calls. Copies of the questionnaire were distributed to a total of 2,246 overseas subsidiaries, and 409 completed responses were collected. Excluding 15 copies that were insufficiently answered, responses from a total of 394 copies were used for analysis. Findings - This study presents the following results. First, there is a U-shaped relationship between levels of HQ control and competency in foreign subsidiaries. This means that higher levels of HQ control negatively impact the competency levels of subsidiaries because strict control undermines autonomy in subsidiaries. However, if the level of HQ control exceeds a certain point, then the transfer of knowledge between HQs and subsidiaries is facilitated. Knowledge transferred from HQs can be used as prior knowledge by foreign subsidiaries to the benefit of all parties. Accordingly, knowledge transfer negates the negative effects of excessive HQ control and positively affects competency in subsidiaries. Second, there is an inverted U-shaped relationship between the local (host-country) experiences of subsidiaries and competency in foreign subsidiaries. This means that foreign subsidiaries can overcome the liabilities of foreignness and contribute to capability building by accumulating unique knowledge about their host countries. However, if local experiences accumulate excessively beyond a certain point, then the host country-specific experiences of foreign subsidiaries will offset the benefits discussed above. Excessive local experiences not only increase organizational inertia, but also create a problem of goal incongruence due to information asymmetry between HQs and subsidiaries. Therefore, excessive local experiences have negative effects on competency in foreign subsidiaries. Originality/value - This study suggests the following implications. First, unlike existing studies based mainly on linear models, this study presents important theoretical implications in its focus on nonlinear models and its analysis of the effects of HQ control and local experiences on competency in foreign subsidiaries from perspectives of organizational learning theory and agency theory. Second, in terms of practical implications, the results of this study suggest that optimally raising levels of HQ control and managing the local experiences of subsidiaries without increasing organizational inertia is important for enhancing competency in foreign subsidiaries.

• 전기학회논문지
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• 제66권5호
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• pp.778-785
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• 2017

This paper presents a control method for reducing the distortion of the grid current at a grid-connected three-level neutral point clamped (NPC) inverter. The grid current is distorted from the 5th and 7th harmonic components in the stationary frame current also the 6th harmonic component in the synchronous frame current. In this paper, the 6th harmonic component on synchronous frame is controlled by using all-pass filters (APFs) and proportional integral (PI) controllers for distortion of the grid side. When transformed the 6th harmonic component is controlled, the 5th and 7th harmonic components are reduced. The validity of the proposed control method is verified by simulation and experiment results using a 25kW three-level NPC inverter.

• 제어로봇시스템학회논문지
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• 제20권3호
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• pp.277-288
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• 2014

This article reviews various state estimation methods for nonlinear systems, particularly with a perspective of a process control engineer. Nonlinear state estimation methods can be classified into the following two categories: stochastic approaches and deterministic approaches. The current review compares the Bayesian approach, which is mainly a stochastic approach, and the MHE (Moving Horizon Estimation) approach, which is mainly a deterministic approach. Though both methods are reviewed, emphasis is given to the latter as it is particularly well-suited to highly nonlinear systems with slow sampling rates, which are common in chemical process applications. Recent developments in underlying theories and supporting numerical algorithms for MHE are reviewed. Thanks to these developments, applications to large-scale and complex chemical processes are beginning to show up but they are still limited at this point owing to the high numerical complexity of the method.

• 한국측량학회지
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• 제9권1호
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• pp.37-45
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• 1991

국내에 GPS 측지기준점을 설정하고 GPS의 장거리 측정 정밀도를 고찰할 목적으로 국내의 2개지 점과 일본의 1개지점에서 GPS 관측을 동시에 실시하여 자료처리방법에 따른 위치결정 정밀도를 비교 분석하였다. 그 결과 WGS 84 좌표계 내에서 국내 2지점의 3차원 좌표를 정확하게 설정할 수 있었고, GPS의 장거리 측정능력이 0.1 ppm에 달하는 것으로 입증되었다. 이 결과는 앞으로 국내의 GPS 측지기준점 확보를 위한 기초자료가 될 것으로 기대된다.

• 농촌계획
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• 제21권3호
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• pp.101-112
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• 2015

The objective of this study was to investigate non-point sources (NPS) pollution and prioritize management areas affected by NPS pollution in the Saemangeum Watershed. AHP (Analytical Hierarchy Process) technique was selected to prioritize sub-watersheds for effectively managing NPS pollution in this study areas. Generation properties of NPS pollution, discharge properties of NPS pollution, and runoff properties of NPS pollution were selected and set for AHP. Weighted descriptors including indicators like numbers of livestock, land- and livestock-system loads, rainfall, and impervious area ratio were generalized from 0 to 1 and multiply each index based on screened 17 survey data. The results were visualized as maps which enable resource managers to identify sub-watersheds for effective improving water quality. The sub-watersheds located in Gongdeok-Myeon, Yongji-Myeon, Hwangsan-Myeon of Gimje-Si were selected for managing NPS pollution control areas. This result presented that these sub-watershed are more affected by the pollution from livestock-system than from land-system. The finding from this study can be used to screen sub-watersheds that need further assessment by managers and decision-makers within the study area.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.656-660
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• 2004

The Mobile Mapping System is an effective method to acquire the position and image data using vehicle equipped with the GPS (Global Positioning System), IMU (Inertial Measurement Unit), and CCD camera. It is used in various fields of road facility management, map update, and etc. In the general photogrammetry such as aerial photogrammetry, GCP (Ground Control Point)s are needed to compute the image exterior orientation elements (the position and attitude of camera). These points are measured by field survey at the time of data acquisition. But it costs much time and money. Moreover, it is not possible to make sufficient GCP as much as we want. However Mobile Mapping System is more efficient both in time and money because it can obtain the position and attitude of camera at the time of photographing. That is, Indirect Georeferencing must use GCP to compute the image exterior orientation elements, but on the other hand Direct Georeferencing can directly compute the image exterior orientation elements by GPS/INS. In this paper, we analyze about the positional accuracy comparison of ground point using the Direct Georeferencing and Indirect Georeferencing.

• 한국지형학회지
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• 제28권4호
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• pp.41-52
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• 2021

With the popularization of drones and the ease of use of the Global Navigation Satellite System (GNSS), drone photogrammetry for terrain information has been widely used. Drone photogrammetry enables the realization of high-accuracy three-dimensional topography for the entire area with less effort and time compared to the past direct survey using GNSS or total station. From 3-D topographic data, various topographical analysis is possible. To improve the accuracy of drone photogrammetry, direct GCP surveying in the field is essential, and the numbers and reasonable positioning of GCPs are very important. In the case of beaches or tidal flats on the west coast of Korea, the numbers and location of GCPs are important factors in efficient drone photogrammetry because of the size of the area, difficulties of movement, and the risk from tides. If the RTK (Real-time kinematic) or PPK (Post-processed kinematic) method is used, the increased accuracy of the drone's location enables high-accuracy photogrammetry with a small number of GCPs. This study presents an efficient drone photogrammetry method in terms of time and economy by comparing and analyzing the results of drone photogrammetry using Non-PPK with low-cost PPK-Kit, based on the tests of various numbers and locations of GCPs in the university field including various slopes and structures like coastal terrain.

• 한국방사선학회논문지
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• 제16권2호
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• pp.77-85
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• 2022

본 연구는 설문조사를 통해 혈관조영검사실 종사자의 감염관리 실태를 조사하여 그에 따른 인식도와 수행도를 알아보고자 하였다. P지역에 소재한 종합병원급 이상 10개 병원의 혈관조영검사실에 근무하는 종사자 126명을 대상으로 2022년 1월 3일부터 1월 28일까지 설문조사를 실시하였으며 내용으로는 대상자의 일반적 특성 10문항과 혈관조영검사실의 감염관리의 주요 항목인 4개 영역 즉, 의료기관 내 감염관리체계, 개인위생, 혈관조영검사실 환경, 혈관조영검사실 장비로 구분한 총 56문항을 Likert 5점 척도로 측정하였다. 자료 분석은 SPSS for WindowTM release 25.0을 이용하여 통계 처리를 하였다. 일반적 특성에 따른 각 영역의 인식도와 수행도의 분석은 t-test, one-way ANOVA로 하였고 변수들 간의 관계는 Pearson 상관관계분석을 시행하였다. 결과로는 모든 영역에서 인식도가 수행도보다 높게 나타나 인식의 수준에 비하여 수행력이 낮음을 알 수 있었다. 또한 인식도와 수행도가 양의 상관관계를 보이고 있어 종사자의 인식 정도가 수행력에 유의한 영향을 미치는 감염관리의 중요한 변수임을 알 수 있었다. 따라서 효과적이고 체계적인 감염관리를 위해서 혈관조영검사실의 종사자는 감염관리의 수행도를 반드시 높여야 할 것이며 그러기 위해선 감염관리 교육이 필요할 것으로 생각되며 앞으로 혈관조영검사실 감염관리 지침이 체계화되어야 할 것으로 판단된다.

• 대한공간정보학회지
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• 제16권1호
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• pp.43-48
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• 2008

본 연구에서는 GPS/INS 항공사진측량 기술을 이용하여 1/1,000 수준의 대축척 수치지형도를 제작하고 전통적인 항공사진측량과의 차이점, 즉 정확도, 경제성 등을 평가하여 GPS/INS 항측의 효율성을 평가하였다. 연구결과, 지상 기준점측량 공정에서 약 40%의 작업량 절감효과가 발생한 것으로 나타났으며, 작업지역의 크기에 따른 작업효율성은 1/5,000 항측의 경우 전통적인 방법과 동일한 정확도를 유지하는 것을 기준으로 할 때 대략 10모델과 20모델 블록에서는 55%, 30모델 블록의 경우 60%의 지상기준점이 감소함을 확인하였다.

• 한국산학기술학회논문지
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• 제12권4호
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• pp.1597-1602
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• 2011

150개 군수업체를 대상으로 실시한 설문조사를 통해, 국방규격 및 민간표준 규격에 대한 활용 실태와 국방규격의 KS 부합화에 따른 경제적 효과 분석을 수행하였다. 대부분의 업체에서는 기업에서 활용하는 국방규격이나 인용 규격의 최신 변경사항에 대한 충분한 정보를 얻지 못하는 것으로 나타났다. 특히, 국방규격은 정보에 대한 접근 제한성으로 인해 최신 동향을 파악하기가 어렵다는 응답이 많았는데, 이는 국방규격이나 도면 검색 프로그램에 대한 활용을 통해 다소나마 해결될 것으로 판단된다. 국방규격의 KS 부합화 사업에 대해서는 많은 업체에서 품질향상, 연구 개발기간 단축, 생산성 증대, 표준 구매 및 교육 비용 절감 등과 관련하여 군수품 원가 절감에 다각적으로 기여할 것으로 예상하는 것으로 나타났다.