• 한국콘텐츠학회논문지
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• 제10권3호
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• pp.1-9
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• 2010

본 논문에서는 모바일 환경에서 모션을 추정하기 위하여 특징점을 코너로 선택하고, 기존 코너 검출 알고리즘인 Rosten 알고리즘 보다 모션 추정의 정확성을 높이는 방법을 제안한다. Rosten 알고리즘은 간단한 덧셈과 뺄셈만으로 코너를 검출함에 따라 처리 속도가 빠른 장점이 있지만, 코너를 매칭하면서 모션추정의 성능이 떨어지는 단점을 가지고 있다. 우리는 Normalized Cross Correlation(NCC) 계수를 사용하여 코너를 매칭하고, 두 단계에 걸쳐 부정확한 매칭에 의한 외톨이를 제거한다. 기존의 Rosten 알고리즘과 제안하는 알고리즘을 실제 영상에서 실험을 통하여 성능을 비교하고, 실제 모바일 장치의 응용 프로그램에 적용한다. 제안한 알고리즘이 Rosten 알고리즘 보다 더 정확한 모션을 추정해 냄을 실험 결과 확인하였고, 실제 모바일 환경에서도 실시간으로 동작함을 확인하였다.

• 대한예방한의학회지
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• 제13권1호
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• pp.93-103
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• 2009

Evidences from various countries suggest that toxic heavy metals in herbal medicine may constitute a serious health problem. In order to evaluate whether the toxic heavy metals caused by herbal medicine intake, blood samples collected from 222 patients taking herbal medicine were analyzed. In average levels of analyzed metals, $0.4{\sim}33.9%$ of total samples for 8 metals such as Cd, Co, Cu, Hg, Mn, Ni, Pb and Zn except Cr and Fe exceeded the upper limit for WHO reference value. In analysis of regression coefficients indicating the levels of metals increased or decreased after taking herbal medicine for one month, however, there were different aspects by intake types for herbal medicine. For example, the metals increased by taking decoction in blood samples were as follows; Cd and Pb whether Mn, Ni and Pb as increased metals were identified in the group taking pill and decoction(combined intake group). The odds ratio showing values higher than 1 indicating that people who take herbal medicine would have possibility higher for metal accumulation in blood than that from people who do not take herbal medicine. The metals showing the odds ratio higher than 1 were Hg and Ni in decoction group, and Cd and Hg in combined intake group. However, eight of the total, 10 metals showed the odds ratios lower than 1 by taking herbal medicine. Thus, this may explain the possible role of herbal medicine as a chelator for heavy metals in body.

• Bulletin of the Korean Chemical Society
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• 제23권10호
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• pp.1459-1462
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• 2002

The kinetics of the addition of X-substituted benzylamines (BA) to Y-substituted Benzylideneacetylacetones (BAA) have been investigated in acetonitrile at $25.0^{\circ}C$. The reaction is studied under pseudo-first-order conditions by keeping a large excess of BA over BAA. The addition of BA to BAA occurs in a single step in which the addition of BA to $C_\alpha$ of BAA and proton transfer from BA to $C_\beta$ of BAA take place concurrently with a four-membered cyclic transition state structure. The magnitude of the Hammett ($p_X$) and Bronsted ($\beta_x$) coefficients are rather small suggesting an early tansition state (TS). The sign and magnitude of the cross-interaction constant, $p_{XY}$ (= -0.49), is comparatible to those found in the normal bond formation processes in the $S_N2$ and addition reactions. The normal kinetic isotope effect ($K_H/K_D$ > 1.0) and relatively low $\Delta$H^{${\neq}$}$ and large negative $\Delta$S^{${\neq}$}$ values are also consistent with the mechanism proposed.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2016년도 춘계학술대회
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• pp.79-80
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• 2016

본 논문에서는 마이크로스트립 패치의 양측 복사에지로 이중급전되는 안테나의 설계방법에 대해 연구하였다. 안테나로부터 복사된 전자파의 교차편파 레벨이 저감되도록 두 개의 급전선로가 180도 위상차를 갖도록 한다. 제시된 안테나의 동작원리와 설계방법에 대해 등가회로를 이용하여 설명하였다. 제안된 방법의 등가회로로 계산된 반사계수와 상용 안테나 설계 툴을 이용한 시뮬레이션 결과를 비교하여 본 연구의 타당성을 검증하였다.

• ETRI Journal
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• 제33권4호
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• pp.537-546
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• 2011

This paper introduces an automated method for building height recovery through the integration of high-resolution satellite images and digital vector maps. A cross-correlation matching method along the vertical line locus on the Ikonos images was deployed to recover building heights. The rational function models composed of rational polynomial coefficients were utilized to create a stereopair of the epipolar resampled Ikonos images. Building footprints from the digital maps were used for locating the vertical guideline along the building edges. The digital terrain model (DTM) was generated from the contour layer in the digital maps. The terrain height derived from the DTM at each foot of the buildings was used as the starting location for image matching. At a preset incremental value of height along the vertical guidelines derived from vertical line loci, an evaluation process that is based on the cross-correlation matching of the images was carried out to test if the top of the building has reached where maximum correlation occurs. The accuracy of the reconstructed buildings was evaluated by the comparison with manually digitized 3D building data derived from aerial photographs.

• 임상간호연구
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• 제18권2호
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• pp.307-316
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• 2012

Purpose: The purpose of this study was to develop and test psychometric properties the Korean version of the End-Stage Renal Disease Adherence Questionnaire (KESRD-AQ). The ESRD-AQ, a 46-item, multidimensional, self-administrated questionnaire which was developed to assess treatment adherence to hemodialysis (HD) attendance, medications, fluid restrictions, and diet prescription among patients on maintenance hemodialysis, has been validated. Methods: The KESRD-AQ was developed by performing both translation and backtranslation. The content validity and test- retest reliability of the KESRD-AQ were evaluated by establishing item-level content validity index (I-CVI) and intra-class correlation coefficients (ICC), respectively. Construct validity was assessed by adopting a known-group analysis comparing adheres and non-adherers using Mann-Whitney U Test. Results: 41 Korean-American patients with ESRD on HD from 3 outpatient dialysis centers in California participated in the study. The KESRD-AQ showed excellent content validity (average I-CVI=.96) and test-retest reliability (ICC=.917, p=.004). The construct validity indicated that the KESRD-AQ distinguished adheres and non-adheres (p=.02~.047). Conclusion: The KESRD-AQ is a valid and reliable instrument to measure treatment adherence.

• Child Health Nursing Research
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• 제18권4호
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• pp.157-163
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• 2012

Purpose: This study was conducted to identify the effects of life stress and depression in undergraduates on suicidal ideation. Methods: The participants in this study were 306 nursing students from three different cities. Collected data were analyzed using t-test, ANOVA, Pearson correlation coefficients, and stepwise multiple regression. Results: The mean score for life stress was 48.48, for depression, 28.59, and for suicidal ideation, 5.90. There were positive relationships between depression and life stress, suicidal ideation and life stress, and suicidal ideation and depression. The four factors of life stress, depression, school life, and gender were identified as factors influencing on suicidal ideation in undergraduates. Conclusion: The findings of this study indicate that the establishment of mental health care centers in universities, and development and implementation of nursing intervention programs for suicide prevention would be helpful.

• Structural Engineering and Mechanics
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• 제11권4호
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• pp.423-442
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• 2001

This paper presents a method of elastic-plastic analysis for planar steel frames that provides the accuracy of distributed plasticity methods with the computational efficiency that is greater than that of distributed plasticity methods but less than that of plastic-hinge based methods. This method accounts for the effect of spread of plasticity accurately without discretization through the cross-section of a beam-column element, which is achieved by the following procedures. First, nonlinear equations describing the relationships between generalized stresses and strains of the cross-section are derived analytically. Next, nonlinear force-deformation relationships for the beam-column element are obtained through lengthwise integration of the generalized strains. Elastic-plastic flexibility coefficients are then calculated by differentiating the above element force-deformation relationships. Finally, an elastic-plastic stiffness matrix is obtained by making use of the flexibility-stiffness transformation. Adding the conventional geometric stiffness matrix to the elastic-plastic stiffness matrix results in the tangent stiffness matrix, which can readily be used to evaluate the load carrying capacity of steel frames following standard nonlinear analysis procedures. The accuracy of the proposed method is verified by several examples that are sensitive to the effect of spread of plasticity.

• Nuclear Engineering and Technology
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• 제54권3호
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• pp.1049-1061
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• 2022

Neutron and gamma-ray shielding properties of Inconel 718 reinforced B₄C (0-25 wt%) were investigated using PSD software. Mean free path (MFP), linear and mass attenuation coefficients (LAC,MAC), tenth-value and half-value layers (TVL,HVL), effective atomic number (Z_eff), exposure buildup factors (EBF), and fast neutron removal cross-sections (FNRC) values were calculated for 0.015-15 MeV. It was found that MAC and LAC increased with the decrease in the content of B₄C compound by weight in Inconel 718. The EBFs were computed using G-P fitting method for 0.015-15 MeV up to the penetration depth of 40 mfp. HVL, TVL, and FNRC values were found to range between 0.018 cm and 3.6 cm, between 2.46 cm and 12.087 cm, and between 0.159 cm^-1 and 0.194 cm^-1, respectively. While Inconel 718 provides the maximum photon shielding property since it offered the highest values of MAC and Z_eff and the lowest value of HVL, Inconel 718 with B₄C(25 wt%) was observed to provide the best shielding material for neutron since it offered the highest FNRC value. The study is original in terms of several aspects; moreover, the results of the study may be used in nuclear technology, as well as other technologies including nano and space technologies.

• 한국음향학회지
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• 제28권3호
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• pp.285-289
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• 2009

본 논문에서는 음향학적 반향 제거(AES, acoustic echo suppression)를 위해 주파수영역에서 soft decision 기법에 근거한 새로운 동시통화 검출 (DTD, double-talk detection) 알고리즘을 제안한다. 제시된 방법은 효과적인 DTD를 위해 상관계수 (cross-correlation coefficient)에 기반하여 hard decision을 사용하는 기존의 알고리즘 대신 주파수 영역에서 입력 및 원단신호의 VAD (voice activity detection) 결과와 음성 통계모델에 기반한 soft decision 방법을 도입하여 전역 근단화자존 재확률 (GNSPP, global near-end speech presence probability)을 DTD에 적용한다. 제안된 알고리즘은 기존의 방법과 객관적인 실험을 통해 비교 평가한 결과 다양한 배경잡음 환경에서 우수한 성능을 보였다.