• 제목/요약/키워드: quantification technique

검색결과 216건 처리시간 0.029초

Two-point Dixon기법을 이용한 간의 지방정량화에 Gd-EOB-DTPA가 미치는 영향 (Effect of Gd-EOB-DTPA on Hepatic Fat Quantification using Two-point Dixon Technique)

  • 구노현;최관우;유병규
    • 한국콘텐츠학회논문지
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    • 제17권7호
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    • pp.215-221
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    • 2017
  • 본 연구는 two-point Dixon기법을 이용한 간의 지방정량화 검사 시 가돌리늄 조영제인 Gd-EOB-DTPA가 지방정량화에 어떠한 영향을 미치는지 알아보고자 하였다. 연구방법은 2016년 4월부터 동년 9월까지 two-point Dixon 기법을 이용해 간의 지방정량화 검사를 시행한 60명을, 두 그룹(정상의 간기증자 30명, 비정상의 간 지방증 환자 30명)으로 분류한 후 조영제 주입에 따른 지방분율의 변화를 비교 평가하였다. 연구 결과, 두 그룹 모두 조영제 주입 전 보다 후의 지방분율이 크게 감소(간 기증자 -33.8%, 간 지방증 환자 -47.2%)하는 것으로 나타나 Gd-EOB-DPTA가 지방정량화에 영향을 미친다는 것을 알 수 있었다. 결론적으로 two-point Dixon기법을 이용해 간 지방정량화 검사를 시행할 경우, Gd-EOB-DTPA 주입 전에 영상을 획득해야 지방분율의 변화를 최소화 할 수 있어 정확한 진단을 할 수 있다.

Detection and quantification of structural damage under ambient vibration environment

  • Yun, Gun Jin
    • Structural Engineering and Mechanics
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    • 제42권3호
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    • pp.425-448
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    • 2012
  • In this paper, a new damage detection and quantification method has been presented to perform detection and quantification of structural damage under ambient vibration loadings. To extract modal properties of the structural system under ambient excitation, natural excitation technique (NExT) and eigensystem realization algorithm (ERA) are employed. Sensitivity matrices of the dynamic residual force vector have been derived and used in the parameter subset selection method to identify multiple damaged locations. In the sequel, the steady state genetic algorithm (SSGA) is used to determine quantified levels of the identified damage by minimizing errors in the modal flexibility matrix. In this study, performance of the proposed damage detection and quantification methodology is evaluated using a finite element model of a truss structure with considerations of possible experimental errors and noises. A series of numerical examples with five different damage scenarios including a challengingly small damage level demonstrates that the proposed methodology can efficaciously detect and quantify damage under noisy ambient vibrations.

다속성 의사결정법과 퍼지정량화 이론을 이용한 공정계획 선택에 관한 연구 (A study on process-plan selection via multiple attribute decision-making approach and fuzzy quantification theory)

  • 임춘우;이노성
    • 제어로봇시스템학회논문지
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    • 제3권5호
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    • pp.490-496
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    • 1997
  • This paper describes a new process-plan selection method using a modified Fuzzy Quantification Theory(FQT). The problem of process-plan selection can be characterized by multiple attributes and used subjective, uncertain information. Fuzzy Quantification Theory is used for handling such information because it is a useful tool when human judgment or evaluation is quantified via linguistic variables, and the proposed method is concerned with the selection of a process plan by derivation of the values of categories for each attribute. In this paper, a modified Fuzzy Quantification Theory(FQT) is described and the procedure of this approach is explained and examples illustrated.

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Sensitivity of quantitative symmetry measurement algorithms for convergent beam electron diffraction technique

  • Hyeongsub So;Ro Woon Lee;Sung Taek Hong;Kyou-Hyun Kim
    • Applied Microscopy
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    • 제51권
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    • pp.10.1-10.9
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    • 2021
  • We investigate the sensitivity of symmetry quantification algorithms based on the profile R-factor (Rp) and the normalized cross-correlation (NCC) coefficient (γ). A DM (Digital Micrograph©) script embedded in the Gatan digital microscopy software is used to develop the symmetry quantification program. Using the Bloch method, a variety of CBED patterns are simulated and used to investigate the sensitivity of symmetry quantification algorithms. The quantification results show that two symmetry quantification coefficients are significantly sensitive to structural changes even for small strain values of < 1%.

LII/LIS 기법을 이용한 층류확산화염 매연입자의 정량화 (Quantitative Measurements of Soot Particles in a Laminar Diffusion Flame Using a LII/LIS Technique)

  • 정재우;이원남;한용택;김병수;이춘범;김덕진;이기형
    • 한국연소학회지
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    • 제8권4호
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    • pp.1-8
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    • 2003
  • In this study, the quantification of soot particles in laminar diffusion flame with LII/LIS methods was performed. In these quantification, soot diameter, number density and volume fraction are included. For the quatification of soot particles, calibration tests are needed and the development of algorithm has to be performed. So, in this study, extinction and scattering test at co-flow burner were performed to acquire calibration data. And algorithm for LII/LIS simultaneous measurement for the quantification of soot were developed. The algorithm, which was the quantification of simultaneous photographing using one ICCD camera, to measure LII/LIS signal simultaneously, the best fitted light intensity and acquisition time was needed.

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Sampling Methods for Quantification of Solid-state Phases in Powder Samples with Solid-state NMR Spectroscopy

  • Han, Oc-Hee;Kim, Sun-Ha;Ko, Tae-Jung
    • Bulletin of the Korean Chemical Society
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    • 제30권5호
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    • pp.1077-1079
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    • 2009
  • To minimize the variance in the quantification of solid-state phases in powder samples, gently placing polycrystalline samples one next to another directly in a sample holder is better than trying to mix them homogeneously prior to transferring to a sample holder. However, the solid-state cross polarization-magic angle spinning (CP-MAS) nuclear magnetic resonance (NMR) spectroscopy results demonstrated that it is essential in this sampling method to place all the samples in the location of consistent signal sensitivity. The same sampling method may be employed in other spectroscopic quantification techniques of solid-state phases if the method to limit the sample to the location with uniform signal sensitivity in the sample holder is adapted to each technique.

수량화 제3 방법의 축소 해 (Shrinkage Solution of Quantification Method III)

  • 허명회;이용구
    • 응용통계연구
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    • 제19권2호
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    • pp.331-338
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    • 2006
  • 수량화 제3방법은 일본의 하야시(Hayashi)에 의해 창안된 교차표 분석 기법으로 사회조사 및 마케팅 조사 자료의 분석에서 매우 유용하다. 그러나 반응빈도가 작은 일부 범주들이 특이하게 큰 수량화 값을 갖는 경우가 있어 불안정한 과잉 해석으로 이어지기도 한다. 본 교신은 이 문제를 해결하고자 한 연구로서 수량화 제3방법을 새로 정식화하고 축소 해 (shrinkage solution)를 제안할 것이다. 그리고 실제 조사 자료에 새 방법론을 적용해 보고자 한다.

후두 내시경 영상에서의 성문 분할 및 성대 점막 형태의 정량적 평가 (Segmentation of the Glottis and Quantitative Measurement of the Vocal Cord Mucosal Morphology in the Laryngoscopic Image)

  • 이선민;오석;김영재;우주현;김광기
    • 한국멀티미디어학회논문지
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    • 제25권5호
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    • pp.661-669
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    • 2022
  • The purpose of this study is to compare and analyze Deep Learning (DL) and Digital Image Processing (DIP) techniques using the results of the glottis segmentation of the two methods followed by the quantification of the asymmetric degree of the vocal cord mucosa. The data consists of 40 normal and abnormal images. The DL model is based on Deeplab V3 architecture, and the Canny edge detector algorithm and morphological operations are used for the DIP technique. According to the segmentation results, the average accuracy of the DL model and the DIP was 97.5% and 94.7% respectively. The quantification results showed high correlation coefficients for both the DL experiment (r=0.8512, p<0.0001) and the DIP experiment (r=0.7784, p<0.0001). In the conclusion, the DL model showed relatively higher segmentation accuracy than the DIP. In this paper, we propose the clinical applicability of this technique applying the segmentation and asymmetric quantification algorithm to the glottal area in the laryngoscopic images.

질적변수에 대한 계량화를 통한 사면붕괴 예측모형 (Prediction Modeling through Quantification for Qualitative Variables)

  • 나종화;유혜경;남은미;조완섭
    • 한국산업정보학회논문지
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    • 제14권5호
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    • pp.281-288
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    • 2009
  • 본 논문에서는 수량화 방법과 AHP(Analytic Hierarchy Process) 기법을 사용하여 산사태 발생에 대한 통계적 예측모형을 구축하는데 목적이 있다. 수량화(Quantification) 방법은 질적변수에 수량을 부여하는 통계적 방법으로, 기 조사된 자료에 기반하여 분석을 수행하는 방법이다. 본 논문에서는 서구의 다변량분석 기법인 정준상관분석의 결과를 토대로 수량화 과정을 구체적으로 제안한다. 데이터에 기반한 수량화 방법과는 팔리 AHP 기법은 일종의 다기준 의사결정을 위해 사용되는 기법으로, 설문자료에 기반한 분석법이다. 실제자료에 대한 분석으로 산사태 발생여부를 측정한 자료(한국지질자원연구원 제공)와 전문가 설문을 통해 수집된 자료를 이용하였다. 이들 자료에 대해 수량화 분석과 AHP분석을 통해 산사태 발생여부를 예측할 수 있는 두 종류의 평가표와 함께 로지스틱 회귀를 통한 통계적 예측모형을 개발하였으며, 두 모형간의 성능비교와 안정성 평가를 수행하였다.

로터리 압축기 내부의 오일 거동 가시화 및 정량화 (Visualization and Quantification of Oil Behavior inside Rotary Compressor)

  • 조필재;김윤석;이승갑;윤영;고한서
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1580-1585
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    • 2004
  • A quality of a refrigeration cycle and a reliability of a compressor can be reduced if a refrigerant including excessive lubricating oil is exhausted from the compressor. Thus, the analysis of the oil behavior inside the compressor is required to prevent the problem. A tested rotary compressor with visualization windows has been manufactured in this study to investigate the oil behavior using developed visualization techniques. The oil behaviors at various operating conditions have been quantified to obtain the relationship with the outlet pressure inside the compressor. Also, the effect of the operating conditions on the quantity of the exhausted oil from the rotary compressor has been investigated using the visualization technique.

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