• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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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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• v.14 no.2
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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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• v.22 no.1
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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.

• Korea journal of population studies
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• v.14 no.2
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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.

• East Asian Journal of Business Economics (EAJBE)
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• v.8 no.3
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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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• v.24 no.5
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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.

• Journal of Ocean Engineering and Technology
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• v.33 no.2
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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.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.118-127
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• 2013

The purpose of this study was to know about the influence of consumers' knowledge level(expert vs novice) on their behavioral intentions by the storytelling about local foods. Reviewing previous storytelling studies related to local foods containing each region's traditional food culture in Korea, it can identify that most studies focused on the necessity of storytelling, the discovery of story materials, the importance of storytelling for food tour. Therefore, this study tried to know about how the storytelling about local foods influenced on the consumers' behavioral intentions, and set the attributes of storytelling and the consumers' local food-purchasing region as adjustable variances. Finally, in case that the consumers' knowledge level was low and their food-purchasing regions were not same, this study suggested the attributes of most preferred storytelling by consumers. By doing so, this study tried to discover the storytelling skills of local foods representing each region or to suggest a method to increase the cultural values of each local food in case of creating a story about the local food.

• Korean Journal of Environment and Ecology
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• v.33 no.4
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• pp.462-471
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• 2019

The purpose of this study is to analyze the difference between local residents and tourist groups in the relationship between the motivation for visiting and the satisfaction of Chung Nam Dae which is the leading tourist attraction in the Chungbuk region. We obtained 200 validated samples each of the local residents in Chungcheongbuk-do Province and the tourists from outside of Chungcheongbuk-do Province with experience of visiting Cheongnamdae through the survey using the questionnaire organized through literature research. The analysis result showed that the relationship between motivation and satisfaction varied depending on the overall sample, local residents, and tourist and that the natural relaxation and convenience had a positive impact on satisfaction in all groups. There was a difference in the influence between motivation and satisfaction between the two groups. Four motivational factors, including natural relaxation, convenience, historicity, and relationship had the significant influence on satisfaction for the local residents while two motivational factors, including natural relaxation and convenience, had the significant influence on satisfaction for the tourists. Based on the results of the study, we presented the theoretical and practical implications and suggested follow-up studies.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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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.