• 응용통계연구
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• 제26권5호
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• pp.697-712
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• 2013

다시점 자료 연구에서 일반화추정방정식은 가상관행렬을 잘못 가정하더라도 모수의 일치추정량을 도출하므로 많이 이용된다. 하지만, 결측 체계가 완전임의결측이 아닌 경우에는 편의추정량을 제공하고, 시간-종속적 공변량이 포함된 경우에는 가상관행렬에 따라 회귀계수 추정값이 다르게 도출될 수 있는 문제점이 있다. 결측 체계가 임의결측인 경우에 발생하는 문제를 해결하기 위해 가중 방법과 다중대체 방법을 사용하는 것이 제안되었다. 본 논문에서는 시간-종속적 공변량이 포함된 이분형 반복측정자료를 GEE를 이용하여 분석할 때 다양한 결측 체계에서 일반화추정방정식 방법, 가중 방법, 다중대체 방법의 회귀계수 추정에 대한 로버스트성과 정확성을 모의실험을 통하여 비교해 보았다. 세 가지 방법 모두에서 시간-종속적 공변량의 회귀계수가 시간-독립적 공변량의 회귀계수에 비해 가상관행렬에 따라 추정값의 차이가 크게 나타났다. 다른 두 방법에 비해 다중대체 방법이 가상관행렬의 형태에 대해 더 로버스트하고 편의도 작은 추정치를 도출하였다.

• Tuberculosis and Respiratory Diseases
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• 제83권1호
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• pp.51-60
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• 2020

Background: Programmed death-ligand 1 (PD-L1) expression is tested by immunohistochemistry (IHC)-22C3, SP263, and SP142. The aim of this study is to evaluate the correlation among the three methods of PD-L1 IHC in non-small cell lung cancer (NSCLC) and clinical significance of PD-L1 expression in lung adenocarcinoma with an epidermal growth factor receptor (EGFR)-tyrosine kinase domain mutation. Methods: The results of 230 patients who were pathologically confirmed as having NSCLC; tested using PD-L1 IHC 22C3, SP263, and SP142 methods; and evaluated via the peptide nucleic acid clamping method to confirm EGFR mutation, were analyzed in this study. Results: 164 patients underwent both the SP263 and 22C3 tests. There was a significant positive correlation between the outcomes of the two tests (Spearman correlation coefficient=0.912, p<0.001), with a derived regression equation as follows: 22C3=15.2+0.884×SP263 (R²=0.792, p<0.001). There was no relationship between the expression of PD-L1 and clinical parameters, including EGFR-tyrosine kinase inhibitor (TKI) mutation. The PD-L1 expression in patients treated with EGFR-TKI yielded a 2-month-shorter progression period than that in the PD-L1-negative group. However, this did not reach statistical significance (PD-L1<1% vs. PD-L1≥1%, 10 months vs. 8 months). Conclusion: The results of the 22C3 and those of SP263 methods were in good correlation with one another. Since the PD-L1 expression is not influenced by the EGFR mutation, it is necessary to perform a PD-L1 test to set the treatment direction in the patients with EGFR-mutant NSCLC.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권4호
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• pp.215-219
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• 2019

Objectives: Postoperative paresthesia is a common complication after sagittal split osteotomy (SSO). This study aimed to compare paresthesia among different fixation methods one year postoperative. Materials and Methods: This prospective cohort study assessed subjects in four groups: class II with miniplate fixation (Group 1), class II with three-screw fixation (Group 2), class III with miniplate fixation (Group 3), and class III with three-screw fixation (Group 4). Paresthesia was evaluated one year postoperative based on a 0-10 visual analogue scale. Pearson correlation was used to evaluate associations of age and mandibular movement with paresthesia. ANOVA was used to compare paresthesia among groups. Results: A total of 80 subjects were enrolled, with 20 subjects in each of the four groups. The Pearson correlation test demonstrated a significant correlation between mandibular movement and paresthesia (P=0.001). Comparison of paresthesia among the groups showed significant differences among groups 1 and 2, 2 and 3, and 3 and 4 (P<0.05). Conclusion: The three-screw fixation method led to more paresthesia one year postoperative compared with miniplate fixation. In addition, the magnitude of mandibular movement had a positive correlation with paresthesia.

• 방송공학회논문지
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• 제16권6호
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• pp.962-968
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• 2011

기존의 무손실 압축은 일반적으로 채널간의 상관관계를 고려하지 않고 각각의 채널을 따로 압축하였다. 채널 간 상관관계를 이용하는 경우도 있으나 이들은 위성/항공 영상과 같은 경우에 제한된 것으로서 일반적인 이미지에 대해서는 만족할만한 성능을 얻지 못하였다. 본 논문에서는 컬러 이미지가 갖는 채널 간의 상관관계를 이용하여 무손실 압축의 성능을 향상시키는 방법을 제안하였다. 제안된 방법에서는 채널 간 상관관계를 표현할 수 있도록 하기 위하여, 비대칭 샘플링을 통해 주어진 영상의 모자이크 이미지를 구성하여 압축을 수행하였고, 압축된 모자이크 이미지의 정보를 이용해서 샘플링되지 않은 나머지 이미지를 예측하여 압축할 정보의 양을 감소시켰다. 제안된 방법은 압축 성능을 평가하는데 일반적으로 사용되는 데이터들에 대해서 채널 간 상관관계를 이용하지 않는 방법에 대해 35%, 채널 간 상관관계를 이용한 기존 방법에 대해 10%의 성능 개선을 보인다.

• The Journal of Korean Physical Therapy
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• 제23권5호
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• pp.57-63
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• 2011

Purpose: The aim of this research is to determine whether there is a significant correlation between the angle of the hallux valgus and dorsi-flexion of the 1st metatarsophalangeal joint (1st MPJ) as a physical factor that has a significant influence on healthy human walking. Methods: The subjects of this research were 65 female adults (130 feet) and the methods used included recording of real measurements and conducting a questionnaire. The acquired data is analyzed by the 'Simple Pearson Correlation Analysis' and 'Repeated Measures Analysis' methods. Results: The research result shows that the left area of -0.74706 and the right area of -0.76 have a relatively high negative correlation (p<0.00). Also, after conducting the 'Repeated Measures Analysis of Variance' of the angles of the hallux valgus and dorsi-flexion of the 1st metatarsophalangeal joint (1st MPJ), the result also shows that the left and right areas of -0.75 have a relatively high negative correlation. Conclusion: The present study was performed for the identification of a significant correlation between the angle of the hallux valgus and dorsi-flexion of the 1st MPJ. From the results of this study, we confirmed that there is a clear tendency for the average distribution rates of Hallux Valgus and Hallux Rigidus (Hallux Limitus) of women to show a higher increase in proportion to age.

• 한국식품과학회지
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• 제50권2호
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• pp.244-247
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• 2018

유세포분석기, 형광현미경 계수법과 현재 주로 활용하는 숙주감염에 의한 용균반검사법에 의한 박테리오파지를 계수하는 방법을 Weissella cibaria 박테리오파지로 비교 연구하였다. 상관관계 분석은 피어슨 상관 통계분석, 회귀분석, 차이검정등으로 하였다. 12개의 시료로 유세포분석기와 용균반검사에 의한 계수법을 비교한 결과는 피어슨 분석으로는 96.7%의 상관관계(상관값 r=0.967, $R^2=0.9352$)와 차이검정은 1.063을 보였다. 형광현미경과 용균반검사에 의한 계수법 비교결과는 피어슨 분석으로는 99.0% (상관값 r=0.990, $R^2=0.9811$) 상관관계와 차이검정은 1.605이였다. 그러므로 유세포분석기와 형광현미경 계수법은 용균반검사 계수법과 같이 W. cibaria 박테리오파지 계수에 적합할 것으로 사료된다.

• 한국음향학회지
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• 제9권2호
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• pp.42-52
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• 1990

음향전파 측정에 상호상관법(직접법과 M계열 변조상관법)을 이용하므로서 임펄스 입력에 의한 경우와 같은 결과를 얻을 수 있다는 것과, 또 상호상관법의 특징인 외란노이즈의 영향을 줄일 수 있었던 것 등을 건축음향분야에서 측정계를 대상으로 하여 이론적으로 정리하였다. 또 이들 계측법을 응용하여 흡음재료의 사입사 흡음특성의 측정, 실의 단독 단음응답 및 잔향감쇄 과정의 측정, 음압레벨 분포, 차음성능 등을 측정하고 여러 건축음향측정에서 이들 방법이 유효하다는 것을 실험적으로 확인하였다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.178-182
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• 2007

In this study, we evaluated current raingauge network of Soyanggang dam region applying spatial-correlation analysis and Entropy theory to recommend an optimized raingauge network. In the process of analysis, correlation distance of raingauge stations is estimated and evaluated via spatial-correlation method and entropy method. From this correlation distances, respective influencing radii of each dataset and each methods is assessed. The result of correlation and entropy analysis has estimated correlation distance of 25.546km and influence radius of 7.206km, deducing a decrease of network density from $224.53km^2$ to $122.47km^2$ which satisfy the recommended minimum densities of $250km^2$ in mountainous regions(WMO, 1994) and an increase of basin coverage from 59.3% to 86.8%. As for the elevation analysis the relative evaluation ratio increased from 0.59(current) to 0.92(optimized) resulting an obvious improvement.

• 한국멀티미디어학회논문지
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• 제24권4호
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• pp.528-537
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• 2021

Face recognition has gained significant notice because of its application in many businesses: security, healthcare, and marketing. In this paper, we will present the recognition method using the combination of correlation filters (CF) and Support Vector Machine (SVM). Firstly, we evaluate the performance and compared four different correlation filters: minimum average correlation energy (MACE), maximum average correlation height (MACH), unconstrained minimum average correlation energy (UMACE), and optimal-tradeoff (OT). Secondly, we propose the machine learning approach by using the OT correlation filter for features extraction and SVM for classification. The numerical results on National Cheng Kung University (NCKU) and Pointing'04 face database show that the proposed method OT-SVM gets higher accuracy in face recognition compared to other machine learning methods. Our approach doesn't require graphics card to train the image. As a result, it could run well on a low hardware system like an embedded system.

• 한국환경보건학회지
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• 제47권1호
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• pp.64-77
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• 2021

Objective: Biological monitoring of trace elements in human blood samples has become an important indicator of the health environment. The purpose of this study was to detect and evaluate multiple metal items in blood samples based on ICP-MS, to perform comparative evaluation with the existing analysis method, and to develop and verify a new method. Methods: 100 μL of whole blood from 80 healthy subjects was used to analyze ten metals (Sb, tAs, Cd, Pb, Mn, Hg, Mo, Ni, Se, Tl) using ICP-MS. Verification of the analysis method included calculation of linearity, accuracy, precision and detection limits. In addition, a comparative test with the conventional graphite furnace atomic absorption spectroscopy (GF-AAS) method was performed. In the case of Pb, Cd, and Hg in whole blood, cross-analysis between Pb, Cd, and Hg analysis methods was performed to confirm the difference between the existing method and the new method (ICP-MS). Results: The coefficient of determination (R2) was 0.999 or higher in seven items and 0.995 or higher in three items. The Pb result showed that Pearson's correlation coefficient was very high at 0.983, and the intraclass correlation coefficient was 0.966. The Cd result showed that Pearson's correlation coefficient was 0.917 between the existing method and the new analysis concentration value. Its intraclass correlation coefficient was 0.960, and there was no significant difference between the two groups. Hg had a low correlation at 0.687, and the intraclass correlation coefficient was 0.761, which was lower than that of Pb and Cd. The intra-day and inter-day accuracy of Pd and Cd were satisfactory, but Hg did not meet the criteria for both accuracy and precision when compared with the conventional analysis method. Conclusion: This study can be meaningful in that it proposes a more efficient and feasible analysis method by verifying a blood heavy metal concentration experiment using multiple simultaneous analyses. All samples were processed and analyzed using the new ICP-MS. It was confirmed that the agreement between the two methods was very high, with the agreement between the current and new methods being 0.769 to 0.998. This study proposes an efficient simultaneous methodology capable of analyzing multiple elements with small samples. In the future, studies of various applications and the reliability of ICP-MS analysis methods are required, and research on the verification of accurate, precise, and continuous analysis methods is required.