• Journal of Oral Medicine and Pain
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• v.23 no.1
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• pp.37-44
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• 1998

본연구는 서울대학교 치과병원 구강진단과 악안면 동통진료실에 내원한 환자 중 임상적 검사에 의해 악관절 내장증으로 진단된 총 32명 53개의 측두하악 관절을 대상으로 악관절 조영술이나 자기공명영상을 실시하여 임상적 진단의 정확도를 알아보고 향후 이 결과를 적절히 활용하여 정확한 적응증의 설정에 도움을 주고자 시행되었다. 각 악관절을 임상적 검사, 조영술 및 자기공명영상 검사를 기준으로 정상, 정복성 관절원판 변위, 비정복성 관절원판 변위, 퇴행성 관절 질환을 동반한 정복성 관절원판 변위, 퇴행성 관절 질환을 동반한 비정복성 관절원판 변위로 구분하였다. 이상의 연구를 통하여 다음과 같은 결론을 얻었다. 1. 악관절 내장증으로 내원한 환자 32명, 총 53개 관절중, 정상인 경우가 5예, 정복성 관절원판 변위인 경우가 33예, 비정복성 관절원판 변위인 경우가 14예, 퇴행성 관절 질환을 동반한 정복성 관절원판변위인 경우가 1예이었고, 퇴행성 관절 질환을 동반한 비정복성 관절원판 변위인 경우는 없었다. 2. 악관절 조영술 검사를 시행한 35개의 관절중 임상적 검사와 일치하는 경우는 32개로 그 일치율은 91.1%이었으며, 자기공명영상 검사를 시행한 28개의 관절중 임상적 검사와 일치하는 경우는 20개로 그 일치율은 71.4%이었다. 3. 악관절 조영술 및 자기공명영상 검사를 동시에 시행한 10개 관절중 악관절 조영술 및 자기공명영상검사가 일치하는 경우는 9개이었으며 이중 8개 결과는 임상적 진단과 일치되는 소견을 보였다. 임상적 검사는 악관절 내장증의 진단에 유용한 방법임이 확인되었다. 그러나 임상적으로는 정상으로 진단되었지만 주관적인 증상을 가진 환자에게는 자기공명영상 검사와 악관절조영술 검사 등의 영상진단술식이 필요할 것으로 사료된다.

• Journal of the Korean Data and Information Science Society
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• v.26 no.1
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• pp.89-99
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• 2015

The World Economic Forum and the Korean Ministry of Knowledge Economy have selected big data as one of the top 10 in core information technology. The key of big data is to analyze effectively the properties that do have data. Clustering analysis method of big data techniques is a method of assigning a set of objects into the clusters so that the objects in the same cluster are more similar to each other clusters. Similarity measures being used in the cluster analysis may be classified into various types depending on the nature of the data. In this paper, we studied upper and lower bounds for binary similarity measures with negative matches such as Russel and Rao measure, simple matching measure by Sokal and Michener, Rogers and Tanimoto measure, Sokal and Sneath measure, Hamann measure, and Baroni-Urbani and Buser mesures I, II. And the comparative studies with these measures were shown by real data and simulated experiment.

• Korean Journal of Cognitive Science
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• v.21 no.4
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• pp.535-557
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• 2010

Researchers have shown the negative compatibility effect (NCE) consistently using arrows. However, they provided inconsistent interpretations about the reason why the NCE happens. The purpose of the present study is to test the factors suggested to be critical for the NCE including automatic inhibition, updated information and top-down control. Presented with arrays of masked prime and targets composed of colored double-headed arrows, participants demonstrated invulnerable NCE on the basis of direction of arrows in the judgment of direction with corresponding hands (Experiment 1), with reverse-mapping hands (Experiment 2) and even in the color-judgment task (Experiment 3). These results imply that the main sources of NCE might be perceptual dominance and inherent properties of stimuli and responses; this contrasts with previously proposed explanations.

• Journal of Digital Convergence
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• v.13 no.7
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• pp.109-116
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• 2015

This paper aimed to identify the relationship between satisfaction and continuous usage intention of AT(Accounting Technician) certification program using WBI(Web-Based Instruction) in the digital convergence environment. We extend satisfaction and continuous usage intention, technology acceptance model theory by adding usefulness expectation, program interface, expectation confirmation. This study was examined by using the SPSS 21.0 and AMOS 21.0. The results by analysis are as follows. First, usefulness expectation and program interface showed positive effect on the expectation confirmation, usefulness expectation had more significantly effect than the program interface. Second, expectation confirmation had significantly positive effect satisfaction, continuous usage intention. Also expectation confirmation was influenced by continuous usage intention rather than satisfaction. Third, satisfaction had positive sign on the continuous usage intention.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.2D
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• pp.203-208
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• 2011

Traffic demand is continuously increasing due to the development of urban areas in Korea. To cope with this, many efforts have been done including constructions of new roadways and increasing the number of lanes of the existing roadways. Those efforts, however, have been performed for only a short segment of target links having similar traffic characteristics. As a result, most urban cities experience bottle-neck phenomena which lead decreasing flow speed and increasing possibilities of accidents. Thus, this study aims to analyze problems of bottle-neck phenomena and effects of balancing number of lanes along the same corridor having similar traffic characteristics. For this, Route 32 passing the city of Daejeon in Korea has been selected as a case study, and a micro-simulation tool, VISSIM, has been adopted for the analysis. The results show that balanced number of lanes along the same corridor with similar traffic characteristics can increase flow speeds and enhance safety.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4303-4312
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• 2013

Study explores the effect of the member's social enterpreneurship at nonprofit organizations on cooperative behavior and proved the mediator effect of value congruency among individuals at those organizations. Examined on a nationwide scale with members at nonprofit organizations, this study indicated followings: 1. Innovativeness, Risk Management, and Social Mission. are valid 2. Innovativeness and Social Mission are related to cooperative behavior, 3. Value congruency with each other at an institution exerts positive effect on cooperative behavior, 4. Value congruency over social enterpreneurship and cooperative behavior partially, yet still positively, mediate social enterpreneurship to cooperative behavior. In other words, the higher the social enterpreneurship in each indivisual is, the higher the degree of value congruency among individuals is, leading to more frequent cooperative behavior. This study also suggests that enhancement of social enterpreureship in each individual at work through education should be considered.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.4
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• pp.284-291
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• 2021

In this paper, we study the consensus problem for multi-agent systems with input saturations. The goal of consensus is to achieve a swarming behavior of multi-agent systems by reaching the agreement through information exchange. This paper considers agents modeled by first-order dynamics with input saturations. In order to guarantee the global convergence of the agents, it is assumed that the agents are stable. Moreover, considering the disturbances, we propose the PI based duplex control method to achieve the consensus. The proposed P controller and I controller are composed of different information network. Then, we investigate the conditions of the information networks and the control gains of P, I controllers to achieve the consensus applying the Lyapunov stability theorem and the Lasalle's Invariance Principle. Finally, we conduct the simulations to validate the theoretical results.

• Pediatric Infection and Vaccine
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• v.23 no.1
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• pp.18-24
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• 2016

Purpose: There is a the great diagnostic challenge in pediatric tuberculosis especially in high burden setting. The purpose of this preliminary study is to evaluate the agreement between tuberculin skin test (TST) and interferon-gamma release assay (IGRA) including T-SPOT$^{(R)}$.TB and QuantiFERON$^{(R)}$-TB Gold (QFT-G) in Korean children. Method: This retrospective study included children and adolescents who visited to Asan Medical Center to evaluate tuberculosis infection using at least two assays of TST, T-SPOT.TB and QFT-G, from January 2014 to April 2015. Results: A total of 20 patients were included, whose median age was 13.3 years (range, 3.8-18.1 years), and all of them had history of BCG vaccination. Eleven patients had underlying diseases including 7 patients with immunosuppressant medication. The concordance rate between T-SPOT.TB and QFT-G was 90%. However, the concordance rate between TST and T-SPOT.TB was 50%, and between TST and QFT-G was 42.9%. Specificity for the diagnosis of tuberculosis infection of T-SPOT.TB, QFT-G, and TST was 93.3%, 86.7%, and 58.3%, respectively. Conclusions: Although there was a discrepancy between TST and IGRA to diagnose tuberculosis, agreement between T-SPOT.TB and QFT-G was relatively high. Further prospective study to validate the clinical usefulness of each assay for immunologic evidence of tuberculosis infection in Korean children will be mandatory.

• Korean Journal of Cognitive Science
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• v.26 no.1
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• pp.1-26
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• 2015

The purpose of this study was to examine whether the phonological information or the orthographic information plays a major role in visual word recognition. To do so, we used a non-word lexical decision task(LDT) in Experiment 1 and masked priming tasks in Experiement 2 and 3. The results of Experiment 1 showed that reaction times and the error rates were affected by the orthographic characteristics of the non-word stimuli such that orthographically similar non-words condition showed prolonged reaction times and higher error rates than control condition. In Experiment 2 and Experiment 3, the participants performed masked priming lexical decision tasks in two SOA conditions(60ms, 150ms). The results of the both experiments showed that the orthographically identical first syllable priming facilitated lexical decision of the target words while both of the pseudo-homophone priming and the phonologically identical first syllable priming did not. The dual route hypothesis(Coltheart et al, 2001), assuming that orthographic information rather than phonological information is the major source for the visual word recognition processes, fits well with the results of the current study.

• Journal of Korea Technology Innovation Society
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• v.14 no.1
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• pp.22-39
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• 2011

This study examines the wage level from a viewpoint of major-job match as part of an analysis on the skill mismatch problem in 4-year college graduates. The empirical analysis explicitly incorporate the sample selection bias as an econometric problem not only suggested but merely introduced in the earlier studies. This study also set up a major-job match variable, which was usually handled as a binary variable for analytical convenience, as a polychotomous choice variable in selection equation as provided by the survey. In particular, it considered multi-cohort survey on graduates of the years 1982, 1992, and 2002 for the empirical analysis. As a result of empirical analysis, the wage premium of a major-job match was identified. This result was consistent after the consideration of a sample selection bias and also after modeling the major-job match variable as polychotomously selective. Through an analysis classified by the major, this study identified a relatively high wage premium among Social Science, Engineering, and Science majors. However, there was a difference in the effect of selection among these majors. Also, by assessing cohort effects this study found that the skill mismatch had rapidly progressed in 1992, while difference between 1992 and 2002 cohorts are insignificant. The analysis suggests that wage level is better understood within the context of both sample selection and major-job match, and regardless of model specification the major-job match affects wage strongly.