• Journal of the Korean Geotechnical Society
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• v.22 no.6
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• pp.63-69
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• 2006

In this paper, a method is presented for estimating the bearing capacity of shallow foundations based on the Discrete Element Method (DEM). By applying Winkler-springs for accounting for the compatibility between soil blocks, the proposed method can estimate the state of stress at failure surface and the ultimate bearing capacity. For the investigation of the application of the method, example problems about shallow foundations on the single layer and two layers soil are analyzed.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.669-675
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• 2020

This research has focused on comparing the capacity predicted by the theoretical formula with the one measured by field load tests to examine characteristics of the bearing capacity of a helical pile. The helical pile is featured by a central shaft with one or more helical-shaped bearing plates. Being established by a small rotary attached to an excavator that applies toque, the helical piles can be readily constructed at narrow sites, especially in an urban area with relatively less noise than the others requiring driving and excavation. Although many cases of the helical pile constructions can be recently found, the bearing capacity of the pile has been limitedly studied. To this end, this contribution analyzes and presents comprehensive results of the ten field loading tests with an application of different parameters depending on joint condition and specification of the helical piles, and types of tests and grouting.

• Journal of the Korean GEO-environmental Society
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• v.14 no.1
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• pp.43-51
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• 2013

Recently, engineering problems such as long-term settlement, differential settlement, and the resultant structural damage, have been frequently reported at construction sites. Use of Sand Compaction Piles(SCP) and Granular Compaction Piles(GCP) are good at remedying existing problems, improving bearing capacity and promoting consolidation. However, such compaction piles have the potential for clogging, which would limit their usability. Investigations into the potential for clogging in SCP, GCP, and GCP mixed with sand has not been thoroughly conducted and is the objective of this current study. Large scale direct shear tests were performed on sections of SCP, GCP, and sand mixed GCP to evaluate bearing capacity. Discrete Element Method analyses were conducted with PFC3D and Finite Element Analyses were conducted with MIDAS GTS to propose an algorithm to help reduce clogging in the granular compaction piles. Results from the large scale direct shear test and multiple simulations suggest a 70% gravel and 30% sand mixing ratio to be optimal for bearing capacity and reducing clogging.

• The Korean Journal of Applied Statistics
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• v.22 no.2
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• pp.375-385
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• 2009

For 2007 Korea presidential election, most polls by telephone surveys indicated Lee Myung-Bak led the second runner-up Jung Dong-Young by certain margin. The margin between two candidates can be estimated accurately by averaging individual poll results, provided there exists no systematic bias in telephone surveys. Most Korean telephone surveys via telephone directory are based on quota samples, with the region, the gender and the age-band as quota variables. Thus the surveys may result in certain systematic bias due to unbalanced factors inherent in quota sampling. The aim of this study is to answer the following questions by the analytic methods adopted in Huh et al. (2004): Question 1. Wasn't there systematic bias in estimates of support rates. Question 2. If yes, what was the source of the bias? To answer the questions, we collected eighteen surveys administered during the election campaign period and applied the iterated proportional weighting (the rim weighting) to the last eleven surveys to obtain the balance in five factors - region, gender, age, occupation and education level. We found that the support rate of Lee Myung-Bak was over-estimated consistently by 1.4%P and that of Jung Dong-Young was underestimated by 0.6%P, resulting in the over-estimation of the margin by 2.0%P. By investigating the Lee Myung-Bak bias with logistic regression models, we conclude that it originated from the under-representation of less educated class and/or the over-representation of house wives in telephone samples.

• Journal of Legislation Research
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• no.54
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• pp.39-69
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• 2018

In $j{\ddot{u}}ngster$ Zeit wird eine Fiktion im Verwaltungsrecht als essentielles Instrument $f{\ddot{u}}r$ Deregulierung sowie Verwaltungsvereinfachung mehr und mehr ins Feld $gef{\ddot{u}}hrt$ und ihre Erweiterung gefordert, weil sie in der Regel auf das Zeitsparen durch Verfahrenswegfall zielt. In Deutschland $erh{\ddot{o}}hte$ sich eine Bedeutung der Genehmigungsfiktion, indem sie durch 4.Novelle des VwVfG, die bei der Umsetzung der Richtlinie 2006/123/EG $ben{\ddot{o}}tigt$ wurde, als ein allgemeines verwaltungsrechtliches Rechtsinstitut eingeordnet wird. In Korea gibt es $vielf{\ddot{a}}ltige$ Fiktionsmethode, $w{\ddot{a}}hrend$ im deutschen Recht die Fiktion lediglich darin besteh, nach Ablauf der festgesetzten Frist die Entscheidung bzw. den Verwaltungsakt anzunehmen. Die systematische und logische Festsetzung der Fiktionslehre in Korea ist erforderlich. Deshalb wird eine allgemeine Regel zur Fiktion durch eine Kodifikation des allgemeinen Verwaltungsgesetzes, wie VwVfG, gefordert.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.203-217
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• 2014

This study is performed to verify the relationship between Korean's anniversary days and meals. To do so, three steps are carried out. First, literature review and mini focus group interview are performed to list up important anniversary days in our culture. Second, anniversary orientation scale(22 items) is developed. Third, a survey(n=486) is implemented to identify the relationship among demographic variables such as sex, age, and perceived economic level, psychological ariables such as self-esteem, life satisfaction, depression, individuality-relatedness, interpersonal sensitivity, materialism as a value and perceived social support, and meal frequency. The results are as follows: Female is significantly higher than male in anniversary orientation. And younger people(20~39 years old) are significantly higher than older people(over 40ties) in anniversary orientation. The higher life satisfaction, perceived social support, relatedness, interpersonal sensitivity, and materialism are, the higher anniversary orientation is. Lastly, middle and high anniversary orientation groups showed more meal frequency at the anniversary day than low anniversary orientation group.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.1
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• pp.117-126
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• 2002

In this paper, 3-D fame design using second-orders plastic-hinge analysis accounting for lateral torsional buckling is developed. This analysis accounts for material and geometric nonlinearities of the structural system and its component members. Moreover, the problem associated with conventional second-order plastic-hinge analyses, which do not consider the degradation of the flexural strength caused by lateral torsional buckling, is overcome. Efficient ways of assessing steel frame behavior including gradual yielding associated with residual stresses and flexure, second-order effect, and geometric imperfections are presented. In this study, a model consisting of the unbraced length and cross-section shape is used to account for lateral torsional buckling. The proposed analysis is verified by the comparison of the LRFD results. A case studs shows that lateral torsional buckling is a very crucial element to be considered in second-order plastic-hinge analysis. The proposed analysis is shown to be an efficient reliable tool ready to be implemented into design practice.

• Journal of the Korean Geographical Society
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• v.44 no.2
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• pp.187-205
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• 2009

Failures on network components of a public transportation system can give rise to the severe degradation of entire system functionality. This paper aims at exploring how potential failures can affect the system flows and reliability of subway network systems in Metropolitan Seoul. To evaluate the range of impacts of disruptions, this research employs a probabilistic approach, network reliability. Network reliability measures the network resiliency and probability of flow loss under a variety of simulated disruptions of critical network components, transfer stations in subway system. By identifying the best and worst scenarios associated with geographical impact, as well as evaluating the criticality of transfer stations, this research presents some insights for protecting current subways systems.

• The Journal of the Korea Contents Association
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• v.21 no.3
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• pp.552-560
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• 2021

This study attempted to explore the experience of patients' having hypertension and diabetes participation in health care. 11 chronic patients who regularly visited community health centers for more than a year participated in this study. The data was collected through individual interviews and analyzed by thematic analysis method. As a result, 6 sub-themes and 3 themes derived from the data. The themes were 'Trying to utilize short consultation time efficiently', 'Answering within narrow limits to healthcare provider', 'Being lack of continuous motivation for health care'. The result showed the need for nurses to provide accurate and sufficient health information and motivate patients in supportive manner to encourage chronic patients' participation in health care.

• Korean Journal of Legislative Studies
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• v.24 no.2
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• pp.67-99
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• 2018

This study analyzes the revision bills of the National Assembly Law in the 19th National Assembly in which the National Assembly Advancement Act was enacted, with the question "who are involved in the revision of the procedural rules, and what motivates them?" The cosponsor network analysis focusing on primary sponsors of the revision bills shows that the network was constructed by party affiliations. A small number of members with high degree centrality attempted to cooperate with each other at the cosponsoring stage, but the legislation did not pass through the related committee. In addition, this study tests the four competitive hypotheses (the committee hypothesis, the distributive politics hypothesis, the ideological distance hypothesis, and the partisan affiliation hypothesis) about the motivation to propose amendments by using the regression models which include newly measured variables. Only the committee hypothesis and the partisan affiliation hypothesis are empirically supported. This implies that partisan consideration is still significant in amending the National Assembly Law even after the National Assembly Advancement Act, and thus party leaders' willingness to seek bipartisan compromises is at the heart of problem-solving.