• Title/Summary/Keyword: multi modes

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The Comparison of Quantitative Indices by Changing an Angle of LAO View in Multi-Gated Cardiac Blood Pool Scan (게이트 심장 혈액풀 스캔에서 좌전사위상 각도의 변화에 따른 정량적 지표 비교)

  • Yoon, Soon-Sang;Nam, Ki-Pyo;Ryu, Jae-Kwang;Kim, Seong-Hwan
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.1
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    • pp.57-61
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    • 2012
  • Purpose: The multi-gated cardiac blood pool scan is to evaluate the function of left ventricle (LV) and usefully observe a value of ejection fraction (EF) for a patient who is receiving chemotherapy. To calculate LVEF, we should adjust an angle of left anterior oblique (LAO) view to separate both ventricles. And by overlapped ventricles, it is possible to affect LVEF. The purpose of this study is to investigate and compare quantitative indices by changing an angle of LAO view. Materials and methods: We analyzed the 49 patients who were examined by multi-gated cardiac blood pool scan in department of nuclear medicine at Asan Medical Center from June to September 2011. Firstly, we acquired "Best septal" view. And then, we got images by addition and subtraction of angle for LAO view to anterior and lateral. We compared three LAO views for 20 people by 5 degrees and 39 people by 10 degrees. And we analyzed quantitative indices, EF, end diastole and end systole counts, by automated and manual region of interest (ROI) modes. Results: Firstly, we analyzed quantitative indices by automated ROI mode. In case of 5 degrees, the averages of EF are $61.0{\pm}7.5$, $62.1{\pm}7.1$, $60.9{\pm}6.7%$ ($p$=0.841) in LAO, LAO $-5^{\circ}$ and LAO $+5^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). In case of 10 degrees, the averages of EF are $62.4{\pm}9.5$, $62.3{\pm}10.8$, $61.6{\pm}.9.3%$ ($p$=0.938) in LAO, LAO $-10^{\circ}$ and LAO $+10^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). Secondly, we analyzed quantitative indices by manual ROI mode. In case of 5 degrees, the averages of EF are $62.8{\pm}7.1$, $63.6{\pm}7.5$, $62.7{\pm}7.3%$ ($p$=0.903) in LAO, LAO $-5^{\circ}$ and LAO $+5^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). In case of 10 degrees, the averages of EF are $65.5{\pm}9.0$, $66.3{\pm}8.7$, $63.5{\pm}.9.3%$ (p=0.473) in LAO, LAO $-10^{\circ}$ and LAO $+10^{\circ}$ respectively. And there is no difference in end diastole and end systole counts ($p$<0.05). Conclusion: When an image is nearly "Best septal" view, the difference of LAO angle would not affect to change LVEF. Although there was no difference in quantitative analysis, deviations could happen when to interpret wall motion qualitatively by reading physicians.

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Effect of the Angle of Ventricular Septal Wall on Left Anterior Oblique View in Multi-Gated Cardiac Blood Pool Scan (게이트 심장 혈액풀 스캔에서 심실중격 각도에 따른 좌전사위상 변화에 대한 연구)

  • You, Yeon Wook;Lee, Chung Wun;Seo, Yeong Deok;Choi, Ho Yong;Kim, Yun Cheol;Kim, Yong Geun;Won, Woo Jae;Bang, Ji-In;Lee, Soo Jin;Kim, Tae-Sung
    • The Korean Journal of Nuclear Medicine Technology
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    • v.20 no.1
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    • pp.13-19
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    • 2016
  • Purpose In order to calculate the left ventricular ejection fraction (LVEF) accurately, it is important to acquire the best septal view of left ventricle in the multi-gated cardiac blood pool scan (GBP). This study aims to acquire the best septal view by measuring angle of ventricular septal wall (${\theta}$) using enhanced CT scan and compare with conventional method using left anterior oblique (LAO) 45 view. Materials and Methods From March to July in 2015, we analyzed the 253 patients who underwent both enhanced chest CT and GBP scan in the department of nuclear medicine at National Cancer Center. Angle (${\theta}$) between ventricular septum and imaginary midline was measured in transverse image of enhanced chest CT scan, and the patients whose difference between the angle of ${\theta}$ and 45 degree was more than 10 degrees were included. GBP scan was acquired using both LAO 45 and LAO ${\theta}$ views, and LVEFs measured by automated and manual region of interest (Auto-ROI and Manual-ROI) modes respectively were analyzed. Results $Mean{\pm}SD$ of ${\theta}$ on total 253 patients was $37.0{\pm}8.5^{\circ}$. Among them, the patients whose difference between 45 and ${\theta}$ degrees were more than ${\pm}10$ degrees were 88 patients ($29.3{\pm}6.1^{\circ}$). In Auto-ROI mode, there was statistically significant difference between LAO 45 and LAO ${\theta}$ (LVEF $45=62.0{\pm}6.6%$ vs. LVEF ${\theta}=64.0{\pm}5.6%$; P = 0.001). In Manual-ROI mode, there was also statistically significant difference between LAO 45 and LAO ${\theta}$ (LVEF $45=66.7{\pm}7.2%$ vs. LVEF ${\theta}=69.0{\pm}6.4%$; P < 0.001). Intraclass correlation coefficients of both methods were more than 95%. In case of comparison between Auto-ROI and Manual ROI of each LAO 45 and LAO ${\theta}$, there was no significant difference statistically. Conclusion We could measure the angle of ventricular septal wall accurately by using transverse image of enhanced chest CT and applied to LAO acquisition in the GBP scan. It might be the alternative method to acquire the best septal view of LAO effectively. We could notify significant difference between conventional LAO 45 and LAO ${\theta}$ view.

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A Study on Pseudo N-gram Language Models for Speech Recognition (음성인식을 위한 의사(疑似) N-gram 언어모델에 관한 연구)

  • 오세진;황철준;김범국;정호열;정현열
    • Journal of the Institute of Convergence Signal Processing
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    • v.2 no.3
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    • pp.16-23
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    • 2001
  • In this paper, we propose the pseudo n-gram language models for speech recognition with middle size vocabulary compared to large vocabulary speech recognition using the statistical n-gram language models. The proposed method is that it is very simple method, which has the standard structure of ARPA and set the word probability arbitrary. The first, the 1-gram sets the word occurrence probability 1 (log likelihood is 0.0). The second, the 2-gram also sets the word occurrence probability 1, which can only connect the word start symbol and WORD, WORD and the word end symbol . Finally, the 3-gram also sets the ward occurrence probability 1, which can only connect the word start symbol , WORD and the word end symbol . To verify the effectiveness of the proposed method, the word recognition experiments are carried out. The preliminary experimental results (off-line) show that the word accuracy has average 97.7% for 452 words uttered by 3 male speakers. The on-line word recognition results show that the word accuracy has average 92.5% for 20 words uttered by 20 male speakers about stock name of 1,500 words. Through experiments, we have verified the effectiveness of the pseudo n-gram language modes for speech recognition.

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Development of a Computation Code for the Verification of the Vulnerability Criteria for Surf-riding and Broaching Mode of IMO Second-Generation Intact Stability Criteria (IMO 2세대 선박 복원성 기준에 따른 서프라이딩/ 브로칭 취약성 기준 검증을 위한 계산 코드 개발)

  • Shin, Dong Min;Oh, Kyoung-gun;Moon, Byung Young
    • Journal of Ocean Engineering and Technology
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    • v.33 no.6
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    • pp.518-525
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    • 2019
  • Recently, the Sub-Committee on SDC (Ship Design and Construction) of IMO have discussed actively the technical issues associated with the second-generation intact stability criteria of ships. Generally, second generation intact stability criteria refer to vulnerability five modes ship stability which occurs when the ship navigating in rough seas. As waves passes the ship, dynamic roll motion phenomenon will affect ship stability that may lead to capsizing. Multi-tiered approach for second generation of intact stability criteria of IMO instruments covers apply for all ships. Each ship is checked for vulnerability to pure loss of stability, parametric roll, and broaching/surf-riding phenomena using L1(level 1) vulnerability criteria. If a possible vulnerability is detected, then the L2(level 2) criteria is used, followed by direct stability assessment, if necessary. In this study, we propose a new method to verify the criteria of the surf-riding/broaching mode of small ships. In case, L1 vulnerability criteria is not satisfied based on the relatively simple calculation using the Froude number, we presented the calculation code for the L2 criteria considering the hydrodynamics in waves to perform the more complicated calculation. Then the vulnerability criteria were reviewed based on the data for a given ship. The value of C, which is the probability of the vulnerability criteria for surf-riding/broaching, was calculated. The criteria value C is considered in new approach method using the Froude-Krylov force and the diffraction force. The result shows lower values when considering both the Froude-rylov force and the diffraction force than with only the Froude-Krylov force was considered. This difference means that when dynamic roll motion of ship, more exact wave force needs considered for second generation intact stability criteria This result will contribute to basic ship design process according to the IMO Second-Generation Intact Stability Criteria.

Sedimentologic Characteristics of the Erosional Coast in the Tide-dominated Environment (대조차환경 침식연안의 퇴적학적 특성)

  • Kum, Byung-Chul;Oh, Jae-Kyung
    • Journal of the Korean earth science society
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    • v.23 no.7
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    • pp.565-574
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    • 2002
  • Based on previous investigations of aerial photographs and topographical surveys, this study focuses on the sedimentologic features of the Daebudo area including sedimentation processes, sedimentary facies and hydrologic conditions of the erosional coast. A total of 137 surface sediments and one core (by hand auger) sediment were obtained to interpret the depositional environment of the erosional coast in the macro-tidal coast. Surface sediments are distributed from sandy gravel (sG) to silt (Z). Textural parameters are characterized not only by coarse, poorly sorted, positive skewed and multi-modal distribution in the supra-tidal flat, but also finer, relatively well-sorted, symmetric distribution in the intertidal flat. According to the C/M diagram, sediment transport modes of study area are characterized by the mixed mode of suspension and bedload in the upper-, middle-tidal flat and by uniform suspension in the lower-tidal flat due to tidal effect. Vertical sediment distribution of the core, collected near shoreline, shows coarsening-upward, poorly sorted pattern by the input of detritus resulting from coastal erosion. Considering the sedimentological features of the study area, it appears to be composed of a coastal zone changed by not only artificial reclamation, but also by natural processes such as strong wave action due to typhoons and storms during high water level and long/short-term sea level rising. As a result, tide-dominated erosional coasts show that the shore is affected by local, temporal and hydrological conditions near high tide level and that the intertidal flat is represented by a general tide-dominated sedimentary environment.

Application of Smartphone Camera Calibration for Close-Range Digital Photogrammetry (근접수치사진측량을 위한 스마트폰 카메라 검보정)

  • Yun, MyungHyun;Yu, Yeon;Choi, Chuluong;Park, Jinwoo
    • Korean Journal of Remote Sensing
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    • v.30 no.1
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    • pp.149-160
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    • 2014
  • Recently studies on application development and utilization using sensors and devices embedded in smartphones have flourished at home and abroad. This study aimed to analyze the accuracy of the images of smartphone to determine three-dimension position of close objects prior to the development of photogrammetric system applying smartphone and evaluate the feasibility to use. First of all, camera calibration was conducted on autofocus and infinite focus. Regarding camera calibration distortion model with balance system and unbalance system was used for the decision of lens distortion coefficient, the results of calibration on 16 types of projects showed that all cases were in RMS error by less than 1 mm from bundle adjustment. Also in terms of autofocus and infinite focus on S and S2 model, the pattern of distorted curve was almost the same, so it could be judged that change in distortion pattern according to focus mode is very little. The result comparison according to autofocus and infinite focus and the result comparison according to a software used for multi-image processing showed that all cases were in standard deviation less than ${\pm}3$ mm. It is judged that there is little result difference between focus mode and determination of three-dimension position by distortion model. Lastly the checkpoint performance by total station was fixed as most probable value and the checkpoint performance determined by each project was fixed as observed value to calculate statistics on residual of individual methods. The result showed that all projects had relatively large errors in the direction of Y, the direction of object distance compared to the direction of X and Z. Like above, in terms of accuracy for determination of three-dimension position for a close object, the feasibility to use smartphone camera would be enough.

A Study on Fault Detection Monitoring and Diagnosis System of CNG Stations based on Principal Component Analysis(PCA) (주성분분석(PCA) 기법에 기반한 CNG 충전소의 이상감지 모니터링 및 진단 시스템 연구)

  • Lee, Kijun;Lee, Bong Woo;Choi, Dong-Hwang;Kim, Tae-Ok;Shin, Dongil
    • Journal of the Korean Institute of Gas
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    • v.18 no.3
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    • pp.53-59
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    • 2014
  • In this study, we suggest a system to build the monitoring model for compressed natural gas (CNG) stations, operated in only non-stationary modes, and perform the real-time monitoring and the abnormality diagnosis using principal component analysis (PCA) that is suitable for processing large amounts of multi-dimensional data among multivariate statistical analysis methods. We build the model by the calculation of the new characteristic variables, called as the major components, finding the factors representing the trend of process operation, or a combination of variables among 7 pressure sensor data and 5 temperature sensor data collected from a CNG station at every second. The real-time monitoring is performed reflecting the data of process operation measured in real-time against the built model. As a result of conducting the test of monitoring in order to improve the accuracy of the system and verification, all data in the normal operation were distinguished as normal. The cause of abnormality could be refined, when abnormality was detected successfully, by tracking the variables out of the score plot.

Mode Choice Behavior Analysis of Commuter Feeder Passengers to Subway System (통근.통학자의 지하철 연계교통수단 선택행태분석)

  • 정헌영;김정주
    • Journal of Korean Society of Transportation
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    • v.18 no.5
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    • pp.69-82
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    • 2000
  • When new subway lines are considered to construct in a large city, there is a need to establish the appropriate transfer systems between subway and other transit modes, so as to increase the use of subway system. In this study, a multi-nominal logit model is developed to analyze the travel characteristics and the mode choice of subway Passengers transferring to and from the buses, minibuses and taxi. These passengers represent a large Portion of transit Passengers in Pusan city It shows that the explanatory variables that affect Passengers\` mode choice are in order of OVIT(Out-of-Vehicle Travel Time), IVTT(In-Vehicle Travel Time), transit fare,. income, gender, and age in modeling. In particular, OVTT is shown to have more significant impact on the mode choice than IYTT due to the fact that transfer trip is involved only in a short distance. Variables associated with the travel costs, however, do have an insignificant impact on the mode choice. It shows that it would be a better Policy to improve the quality of transit service using additional financial resource by increasing transit fare rather than by reducing the fare to increase travel demand. It also shows that value of travel time of OVTT is remarkably higher than that of IVTT and value of travel time of taxi Passengers is much higher than that of minibus Passengers .

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MPEG-H 3D Audio Decoder Structure and Complexity Analysis (MPEG-H 3D 오디오 표준 복호화기 구조 및 연산량 분석)

  • Moon, Hyeongi;Park, Young-cheol;Lee, Yong Ju;Whang, Young-soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.42 no.2
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    • pp.432-443
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    • 2017
  • The primary goal of the MPEG-H 3D Audio standard is to provide immersive audio environments for high-resolution broadcasting services such as UHDTV. This standard incorporates a wide range of technologies such as encoding/decoding technology for multi-channel/object/scene-based signal, rendering technology for providing 3D audio in various playback environments, and post-processing technology. The reference software decoder of this standard is a structure combining several modules and can operate in various modes. Each module is composed of independent executable files and executed sequentially, real time decoding is impossible. In this paper, we make DLL library of the core decoder, format converter, object renderer, and binaural renderer of the standard and integrate them to enable frame-based decoding. In addition, by measuring the computation complexity of each mode of the MPEG-H 3D-Audio decoder, this paper also provides a reference for selecting the appropriate decoding mode for various hardware platforms. As a result of the computational complexity measurement, the low complexity profiles included in Korean broadcasting standard has a computation complexity of 2.8 times to 12.4 times that of the QMF synthesis operation in case of rendering as a channel signals, and it has a computation complexity of 4.1 times to 15.3 times of the QMF synthesis operation in case of rendering as a binaural signals.

On-line Fundamental Frequency Tracking Method for Harmonic Signal and Application to ANC (조화신호의 실시간 기본 주파수 추종 방법과 능동소음제어에의 응용)

  • Kim, Sun-Min;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.263-268
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    • 2000
  • In this paper, a new indirect feedback active noise control (ANC) scheme based on the fundamental frequency estimation is proposed for systems with a harmonic noise. When reference signals necessary for feedforward ANC configuration is difficult to obtain, the conventional ANC algorithms for multi-tonal noise do not measure the reference signals but generate them with the estimated frequencies. However, the beating phenomena, in which certain frequency components of the noise vanish intermittently, may make the adaptive frequency estimation difficult. The confusion in the estimated frequencies due to the beating phenomena makes the generated reference signals worthless. The proposed algorithm consists of two parts. The first part is a reference generator using the fundamental frequency estimation and the second one is the conventional feedforward control. We propose the fundamental frequency estimation algorithm using decision rules, which is insensitive to the beating phenomena. In addition, the proposed fundamental frequency estimation algorithm has good tracking capability and lower variance of frequency estimation error than that of the conventional cascade ANF method. We are also able to control all interested modes of the noise, even which cannot be estimated by the conventional frequency estimation method because of the poor SIN ratio. We verify the performance of the proposed ANC method through simulations for the measured cabin noise of a passenger ship and the measured time-varying engine booming noise of a passenger vehicle.

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