• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2008년도 학술발표회 논문집
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• pp.147-153
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• 2008

본 연구에서는 레이더 강우를 이용하여 시공간적 변동성을 고려한 격자형 면적강우량을 산정하기 위하여 추계학적 방법인 칼만필터 기법을 이용하여 지상 강우 관측망과 레이더 강우 관측망을 조합하여 면적강우량을 산정하였다. 또한 전통적인 지상 강우량을 면적강우량으로 전환하는 기법인 Thiessen법, 역거리법, 크리깅 기법을 이용하여 면적강우량을 산정한 후 칼만필터 기법에 의해 보정된 면적 레이더 강우와 비교 하였다. 그 결과, 칼만필터 기법에 의해 보정된 레이더 강우는 실제 강우 분포와 유사한 공간분포를 가지는 원시 레이더 강우 분포를 잘 재현하면서도 강우 체적(볼륨)은 우량계 자료의 체적과 유사하게 나타났다. 그리고 칼만필터 기법에 의해 보정된 레이더 강우를 물리적 기반의 분포형 모형인 $Vflo^{TM}$ 모형과 준분포형 모형인 ModClark 모형에 적용하여 홍수유출을 모의하였다. 그 결과, $Vflo^{TM}$ 모형은 첨두시간과 첨두치가 관측 수문곡선과 유사하게 모의되었으며 ModClark 모형은 총 유출체적에서 좋은 결과를 나타냈다. 그러나 매개변수 검증에서는 $Vflo^{TM}$ 모형이 ModClark 모형보다 관측 수문곡선을 잘 재현하였다. 이를 통해 지상강우와 레이더 강우를 적절하게 조합하여 정확도 높은 면적강우량을 산정하고 분포형 수문모형과 연계하여 홍수유출모의를 실시할 경우 충분한 적용성을 가지고 있음을 확인할 수 있었다.

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2002년도 춘계학술대회 논문집
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• pp.45-52
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• 2002

Artificial neural networks (ANN) have been successfully used for classifying remotely sensed imagery. However, ANN still is not the preferable choice for classification over the conventional classification methodology such as the maximum likelihood classifier commonly used in the industry production environment. This can be attributed to the ANN characteristic built-in stochastic process that creates difficulties in dealing with unequally represented training classes, and its training performance speed. In this paper we examined some practical aspects of training classes when using a back propagation neural network model for remotely sensed imagery. During the classification process of remotely sensed imagery, representative training patterns for each class are collected by polygons or by using a region-growing methodology over the imagery. The number of collected training patterns for each class may vary from several pixels to thousands. This unequally populated training data may cause the significant problems some neural network empirical models such as back-propagation have experienced. We investigate the effects of training over- or under- represented training patterns in classes and propose the pattern repopulation algorithm, and an adaptive alpha adjustment (AAA) algorithm to handle unequally represented classes. We also show the performance improvement when input patterns are presented in random fashion during the back-propagation training.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.1235-1242
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• 2006

Viscoelastic damping materials are widely used to reduce noise and vibration because of its low cost and easy implementation, for examples, on the body structure of passenger cars, air planes, electric appliances and ships. To design the damped structures, the material property such as elastic modulus and loss factor is essential information. The four-parameter fractional derivative model well describes the nonlinear dynamic characteristics of the viscoelastic damping materials with respect to both frequency and temperature with fewer parameters than conventional spring-dashpot models. However the identification procedure of the four-parameter is very time-consuming one. An efficient identification procedure of the four-parameters is proposed by using an FE model and a gradient-based numerical search algorithm. The identification procedure goes two sequential steps to make measured FRFs coincident with simulated FRFs: the first one is a peak alignment step and the second one is an amplitude adjustment. A numerical example shows that the proposed method is efficient and robust in identifying the viscoelastic material parameters of fractional derivative model.

• 로봇학회논문지
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• 제12권4호
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• pp.385-394
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• 2017

Side scanning sonar (SSS) provides valuable information for robot navigation. However using the side scanning sonar images in the navigation was not fully studied. In this paper, we use range data, and side scanning sonar images from UnderWater Simulator (UWSim) and propose measurement models in a feature based simultaneous localization and mapping (SLAM) framework. The range data is obtained by echosounder and sidescanning sonar images from side scan sonar module for UWSim. For the feature, we used the A-KAZE feature for the SSS image matching and adjusting the relative robot pose by SSS bundle adjustment (BA) with Ceres solver. We use BA for the loop closure constraint of pose-graph SLAM. We used the Incremental Smoothing and Mapping (iSAM) to optimize the graph. The optimized trajectory was compared against the dead reckoning (DR).

• 한국측량학회지
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• 제7권1호
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• pp.11-18
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• 1989

한 나라의 정밀수준망을 구성, 완성하는데는 다양한 장비 및 기술, 오랜 시간이 요구되므로 각각의 측정값에는 각종 오차가 내포되어있다. 따라서 정확한 수준망을 구성하기 위하여는 각각의 수준측량값에 대하여 그 정확도에 상응하는 중량값을 주어야 한다. 본 연구는 수준측대의 오차전파모델로부터 중량값을 추정하고 이를 우리나라 1등수준측량 데이타에 적용시켜봄으로써 적합한 중량함수를 구하고자 하는데 그 목적을 두었으며 아울러 우리나라 1등수준측량에 대한 오차분석을 실시하여 좀더 정확한 수준망을 구성하고자 하였다. 연구결과 우리나라와 같이 비교적 큰 정오차가 내포된 수준망에서는 중량함수 W＝1/L보다 W＝1/$L^2$의 경우가 더 효과적임을 알 수 있었다.

• 디지털융복합연구
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• 제6권1호
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• pp.53-61
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• 2008

For the domestic digital contents, a proactive cooperation system or framework between the government, the businesses and research institutions, which would allow for free flow of interaction among these players, can play that role. We have proposed and realized the Dynamic Coordinating Framework(DCF) to bridge these gaps among the major players in the industry. The the Dynamic Coordinating Framework rests on the following major functions. The first major function of the DCF is to decipher any ambiguity that may be embedded in external inputs by stratified role and bias. The second function is to create cooperative groups that will deal with the ambiguities based on its consequent situation. The third is a feedback function that will draw out a new cooperative way by re-feeding the capacities and the conflicts that stem from the existing organizations and strategies into cooperation and adjustment process. Our DCF has compared and evaluated with England and Australia digital content industry models under AHP(Analytic Hierarchy Process) method. DCF has turned out to be well designed and have strong points based on OECD innovation and cooperation criteria.

• 동아시아경상학회지
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• 제6권4호
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• pp.25-34
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• 2018

Purpose - The purpose of this study is to investigate the effect of Korean Wave on consumer intentions by adjusting the Korean image and image of Korean company to counterbalance the hostility through the control effect of Korean Wave. Research design and methodology - This paper measure individual and national hostility and suggest that the effect of the adjustment of Korean culture satisfaction on corporate image, product image and consumer's purchase intention. Results - This study suggests the subjects to be studied empirically by presenting research themes and models, but it is necessary to verify the model through statistical verification since it is not verified empirically. In addition, it is necessary to further control factors and identification of anti-marginal or anti-marginal products. Conclusions - This study suggests research topics that investigate how hostility affects Korean Wave in consideration of the current special situation, while conventional researches mainly focus on ethnocentrism and patriotism. In this way, this study suggests research direction that helps to enhance corporate image and product image by eliminating hostility and actively utilizing Korean Wave. The Proposal will be helpful to provide a frame for empirical analysis in future and to develop strategic means to further utilize it in international marketing.

• KIEAE Journal
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• 제9권1호
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• pp.3-10
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• 2009

There are more interests and studies to change the buildings into eco-friendly spaces as the present age recognizes nature-friendly environment more and more. In response to this trend, the government reinforces regulations for the variety of the eco-friendly buildings using a certification system. The eco-friendly certification system which was started only for residing since 2002, and this has been now for schools that are the spaces of the students who will lead the future since March 2005. The purpose of this study is to help understanding of the eco-friendly buildings, and to popularize and activate those as developing and making up for the classification system, evaluation items, detailed standards to evaluate them more precisely by analysing eco-friendly planning features and data of the eco-friendly certificated schools. This study selected 15 eco-friendly certified schools among the schools certified by the Ministry of Land, Transport, and Maritime Affaires since 2005, and analyzed evaluation result. After the analysis, I had a thorough grasp of the point distribution of the each building, analyzed the cause of the low points or no points, and tried to find the improvements. There should be continuing adjustment and complement for the evaluation items and detailed standards, and these should be applied to models as well as certified schools. Active public relations are also needed to educate the public and elevate their participation.

• 대한지역사회영양학회지
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• 제11권6호
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• pp.707-713
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• 2006

The purpose of this study was to test whether moderate alcohol consumption has any positive effect on lowering blood pressure among Koreans. Study subjects were Korean adults 20 years or older (n=5,234) who participated in the 2001 Korean National Health and Nutrition Examination Survey (KNHANES). Analysis of variance and analysis of covariance were used to construct univariate and multivariate models relating alcohol consumption to blood pressure for the analysis. After adjustment for possible covariates, drinkers (regardless of drinking level) had significantly higher systolic and diastolic blood pressure, compared with never-drinker for male subjects. Diastolic and systolic blood pressures were also significantly elevated with the drinking frequency and amount of alcohol intake among male subjects. For the female subjects, only diastolic blood pressure was significantly associated with the alcohol consumption at multivariate model. however, low level alcohol consumption did not show any sign of lowing effects on blood pressure. The result implies that moderate alcohol consumption did not have any positive effect on lowering blood pressure among Koreans for either sex.

• 대한산업공학회지
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• 제39권6호
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• pp.577-586
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• 2013

In a shipyard, it is hard to predict block movement due to the uncertainty caused during the long period of shipbuilding operations. For this reason, block movement is rarely scheduled, while main operations such as assembly, outfitting and painting are scheduled properly. Nonetheless, the high operating costs of block movement compel task managers to attempt its management. To resolve this dilemma, this paper proposes a new block movement analysis framework consisting of the following operations: understanding the entire process, log clustering to obtain manageable processes, discovering the process model and detecting exceptional processes. The proposed framework applies fuzzy mining and trace clustering among the process mining technologies to find main process and define process models easily. We also propose additional methodologies including adjustment of the semantic expression level for process instances to obtain an interpretable process model, definition of each cluster's process model, detection of exceptional processes, and others. The effectiveness of the proposed framework was verified in a case study using real-world event logs generated from the Block Process Monitoring System (BPMS).