• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2009년도 IWAIT
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• pp.59-62
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• 2009

In general, as a dynamic range of digital still camera is narrower than a real scene‘s, it is hard to represent the shadow region of scene. Thus, multi-scaled retinex algorithm is used to improve detail and local contrast of the shadow region in an image by dividing the image by its local average images through Gaussian filtering. However, if the chromatic distribution of the original image is not uniform and dominated by a certain chromaticity, the chromaticity of the local average image depends on the dominant chromaticity of original image, thereby the colors of the resulting image are shifted to a complement color to the dominant chromaticity. In this paper, a modified multi-scaled retinex method to reduce the influence of the dominant chromaticity is proposed. In multi-scaled retinex process, the local average images obtained by Gaussian filtering are divided by the average chromaticity values of the original image in order to reduce the influence of dominant chromaticity. Next, the chromaticity of illuminant is estimated in highlight region and the local average images are corrected by the estimated chromaticity of illuminant. In experiment, results show that the proposed method improved the local contrast and detail without color distortion.

• Smart Structures and Systems
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• 제14권2호
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• pp.85-104
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• 2014

Damage detection is a challenging, complex, and at the same time very important research topic in civil engineering. Identifying the location and severity of damage in a structure, as well as the global effects of local damage on the performance of the structure are fundamental elements of damage detection algorithms. Local damage detection is essential for structural health monitoring since local damages can propagate and become detrimental to the functionality of the entire structure. Existing studies present several methods which utilize sensor data, and track global changes in the structure. The challenging issue for these methods is to be sensitive enough in identifYing local damage. Autoregressive models with exogenous terms (ARX) are a popular class of modeling approaches which are the basis for a large group of local damage detection algorithms. This study presents an algorithm, called Influence-based Damage Detection Algorithm (IDDA), which is developed for identification of local damage based on regression of the vibration responses. The formulation of the algorithm and the post-processing statistical framework is presented and its performance is validated through implementation on an experimental beam-column connection which is instrumented by dense-clustered wired and wireless sensor networks. While implementing the algorithm, two different sensor networks with different sensing qualities are utilized and the results are compared. Based on the comparison of the results, the effect of sensor noise on the performance of the proposed algorithm is observed and discussed in this paper.

• Journal of the Korean Statistical Society
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• 제22권1호
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• pp.27-37
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• 1993

Since the analytic expression for a diagnostic in the logistic regression model is not available, one-step estimation is often used by a case-deletion point of view. In this paper, infinitesimal perturbation approach is used, and it is shown that the scale transformation of infinitesimal perturbation approach is eventually equal to the weighted perturbation of local influence approach and the replacement measure. Also, multiple cases deletion for the masking effect is considered.

• 한국인구학
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• 제14권2호
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• pp.1-17
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• 1991

While various fiscal measures have been used to influence regional capital inflow or industrial location, the effect of fiscal variables on labor mobility has been little understood. Understanding the relationship between the composition of local public and urban migration would enhance the city govenment's ability to pursue an appropriate population policy. In order to examine the potential for local public finance to be utilized as a policy tool in directing urban population growth, this paper analyzes the impact of local government financial structure on urban migration. In examining the data on local government finance and the changes in population of Korean cities during the last ten years, it was found that cities with high per capita expenditure in regional development have experienced high population growth rates. In this study migration equations were constructed using various fiscal variables such as the proportion of special account expenditures which are mostly spent for local development purposes, per capita regional development expenditure, degree of local financial independence and per capita net fiscal benefit, along with other explanatory variables. The results of regression analysis showed that city government's regional development expenditure variables have a positive effect on urban net migration and a negative effect on outmigration. Fiscal independence and per capita net fiscal benefit had mixed effects on in and out migration variables, implying that local tax burden does not consistently deter inmigration or induce outmigration. Based on the results of this study some important policy implications can be found regarding local government's fiscal policies. Those cities seeking to attract higher population inflow should make a greater effort in appropriating local expenditures for regional development purposes such as infrastructure, housing, and transportation. city governments should not be too concerned about high local tax burden or necessarily seek to enhance financial independence for these factors do not exert a clear influence on urban population growth or labor supply.

• 동아시아경상학회지
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• 제8권3호
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• pp.43-56
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• 2020

Purpose - This study was carried out to analyze the influential factors of how consumers methodize purchasing agricultural products via direct market. It further utilizes the Discrete Choice Model to analyze consumer decision specifically with regards to individual markets and store attributes. Research design and methodology - This study will use the multinomial logit model to interpret the influential factors behind selecting a specific market to purchase from. This study establishes 'online direct-purchase' as the base category with 'direct farm markets', 'local foods direct markets', 'produce boxes (CSA)' as substitutes. Results - Firstly, the variety of products, price and freshness had a positive influence on choosing 'direct farm markets' while convenience of payment and transportation had a negative influence. Second, freshness and store attributes had a positive influence on choosing 'local foods direct markets' but product price and packaging, location accessibility had a negative influence. And although product creditability had a positive influence on purchasing 'produce boxes (CSA)', product price had a negative influence. Conclusions - Accordingly, there is a need for the South Korean government to encourage the adoption of mobile payment through smartphone applications in direct farm markets to vitalize direct agricultural purchasing. However, this does need to be approached cautiously as price has a conflicting affect for each method of purchase.

• Geomechanics and Engineering
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• 제24권5호
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• pp.479-490
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• 2021

Pre-drainage of groundwater in the roof aquifer by boreholes is the main method for prevention of roof water disaster, and the drop in the water level during the drainage leads to the variation of the local stress in the overlying strata. Based on a multitude of boreholes for groundwater drainage from aquifer above the 1303 mining face of Longyun Coal Mine, theoretical analysis and numerical simulation are used to investigate the local stress variation in the process of borehole drainage. The results show that due to the drop in the water level of the roof aquifer during the drainage, the stress around the borehole gradually evolved. From the center of the borehole to the outside, a stress-relaxed zone, a stress-elevated zone, and a stress-recovered zone are sequentially formed. Along with the expansion of drainage influence, the stress peak in the stress-elevated zone also moves to the outside. When the radius of influence develops to the maximum, the stress peak position no longer moves outward. When the coal mining face advances to the drainage influence range, the abutment pressure in front of the mining face is superimposed with the high local stress around the borehole, which increases the risk of stress concentration. The present study provides a reference for the stress concentration caused by borehole drainage, which can be potentially utilized in the optimal arrangement of drainage boreholes in underground mining.

• 한국해양공학회지
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• 제33권2호
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• pp.161-167
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• 2019

This paper focuses on a newly designed ice load formula based on the ARAON's 2016 Arctic field data in order to improve a structural design against ice loads. The strain gage signals from ARAON's hull plating were converted to the local ice pressure upon the hull plating using the influence coefficient matrix and finite element analysis. First, a traditional pressure-area relationship is derived by applying probabilistic approaches to handle the strains measured onboard the ARAON. Then, the local ice load prediction formula is re-analyzed after reviewing the ARAON's additional field data to consider information about the ship speed and thickness of the sea ice. It is shown that the newly developed pressure-area relationship well reflects the influence of other design parameters such as the ship speed and ice thickness in the prediction of local ice loads on Arctic vessels.

• 한국콘텐츠학회논문지
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• 제13권8호
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• pp.118-127
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• 2013

본 연구에서는 소비자의 지식 수준에 따른 향토음식 스토리텔링에 의한 행동의도를 알아보고자 하였다. 지금까지 우리나라 각 지역의 전통적인 식문화를 담고 있는 향토음식과 관련된 스토리텔링 연구를 살펴보면 대부분의 연구가 음식 스토리텔링의 필요성 제기, 음식 스토리의 소재 발굴, 미식 관광을 위한 스토리텔링의 중요성에 대한 연구에 머무르고 있다. 그러나 본 연구에서는 향토음식 스토리텔링이 소비자의 행동의도에 미치는 영향을 살펴보고자 향토음식과 관련된 지식에 기초하여 스토리텔링의 속성과 향토음식의 구매지역을 조절변수로 두었다. 나아가 지식의 정도가 낮으며, 구매지역이 일치하지 않는 경우 소비자들이 가장 선호하는 스토리텔링의 속성을 제시하고자 한다. 따라서 각 지역을 대표하는 향토음식의 스토리텔링을 발굴 또는 창작할 경우 향토음식의 문화적 가치를 향상시킬 수 있는 스토리텔링 개발 방법을 제시하고자 한다.

• 한국환경생태학회지
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• 제33권4호
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• pp.462-471
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• 2019

본 연구는 충북지역의 대표 관광목적지인 청남대의 방문동기와 만족도 간 영향관계에 있어 지역주민과 관광객 집단 간 차이를 분석하는데 목적이 있다. 문헌연구를 통해 구성한 설문지를 바탕으로 청남대를 방문한 경험이 있는 충북권 지역주민 200부, 충북 외 지역에 거주하고 있는 관광객 200부의 유효표본을 확보하여 분석에 활용하였다. 분석결과, 동기와 만족도간 영향관계는 전체표본, 지역주민, 관광객 집단에 따라 차이가 있는 것으로 나타났으며, 모든 집단에서 공통적으로 자연휴식성과 편리성 요인이 만족도에 긍정적으로 크게 영향을 미치는 것으로 나타났다. 동기와 만족도 간 영향관계에 있어 지역주민은 자연휴식성, 편리성, 역사성, 관계성 등 4개 동기요인, 관광객은 자연휴식성, 편리성 등 2개 동기요인이 만족도에 유의한 영향을 미치는 것으로 나타나 집단 간 차이가 있음을 보여주었다. 연구결과를 바탕으로 이론적 실무적 시사점을 제시하였으며, 후속 연구과제를 제안하였다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.357-364
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• 2006

The meshfree method is extended by the local partition of unity method to model the cohesive cracks in two dimensional continuum The shape function of a particle whose domain of influence is completely cut by a crack is enriched by the step enrichment function. If the domain of influence contains a crack tip inside, it is enriched by the branch enrichment function without the stress singularity. It is found that this method is more accurate and converges faster than the meshless methods for LEFM cracks based on the visibility concept Several staic and dynamic examples are solved to verify the method.