• Journal of Preventive Medicine and Public Health
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• 제53권4호
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• pp.256-265
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• 2020

Objectives: We compared the associations of 3 computed tomography (CT)-based abdominal adiposity indexes with non-alcoholic fatty liver disease (NAFLD) among middle-aged Korean men and women. Methods: The participants were 1366 men and 2480 women community-dwellers aged 30-64 years. Three abdominal adiposity indexes-visceral fat area (VFA), subcutaneous fat area (SFA), and visceral-to-subcutaneous fat ratio (VSR)-were calculated from abdominal CT scans. NAFLD was determined by calculating the Liver Fat Score from comorbidities and blood tests. An NAFLD prediction model that included waist circumference (WC) as a measure of abdominal adiposity was designated as the base model, to which VFA, SFA, and VSR were added in turn. The area under the receiver operating characteristic curve (AUC), integrated discrimination improvement (IDI), and net reclassification improvement (NRI) were calculated to quantify the additional predictive value of VFA, SFA, and VSR relative to WC. Results: VFA and VSR were positively associated with NAFLD in both genders. SFA was not significantly associated with NAFLD in men, but it was negatively associated in women. When VFA, SFA, and VSR were added to the WC-based NAFLD prediction model, the AUC improved by 0.013 (p<0.001), 0.001 (p=0.434), and 0.009 (p=0.007) in men and by 0.044 (p<0.001), 0.017 (p<0.001), and 0.046 (p<0.001) in women, respectively. The IDI and NRI were increased the most by VFA in men and VSR in women. Conclusions: Using CT-based abdominal adiposity indexes in addition to WC may improve the detection of NAFLD. The best predictive indicators were VFA in men and VSR in women.

• Journal of the Korean Data and Information Science Society
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• 제14권3호
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• pp.429-440
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• 2003

Variable sampling rate (VSR) control charts vary the sampling interval and/or the sample size according to value of the control statistic. It is known that $\bar{X}$ charts with VSR scheme lead to large improvements in performance over those with fixed sampling rate (FSR) scheme. In this paper, we studied $\bar{X}$ charts with several VSR schemes, and compared their statistical performance each other.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 한국컴퓨터종합학술대회 논문집 Vol.32 No.1 (A)
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• pp.442-444
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• 2005

본 논문에서는 대규모의 센서 네트워크(Large Scale Sensor Networks)에서 가상 싱크 로테이션(Virtual Sink Rotation) 이라 불리는 새로운 라우팅 프로토콜을 제안 한다. VSR은 많은 수의 소스(source) 와 많은 수의 이동성을 가지는 싱크(sink)를 효율적으로 지원한다. VSR의 주 아이디어는 두 가지로 나뉘는데, 첫 번째는 싱크 이동으로 인한 위치 업데이트를 줄일 수 있는 가상 싱크라는 개념으로 소스 의 데이터를 모으고 모아진 데이터를 싱크에 전달 하여 준다. 두 번째는 싱크 주변의 노드들의 급격한 에너지 소모로 인하여 VSR은 가상 싱크 로테이션 알고리즘을 사용한다. 가상 싱크 로테이션은 네트워크의 노드들이 에너지를 균일하게 소모 시키도록 하고, 네트워크 수명을 늘린다. VSR 라우팅 프로토콜 과 기존에 제안된 논문의 비교 실험 결과를 통하여 에너지 소모, 메시지 지연 시간, 전송 효율 등에서 좋은 성능을 가지는 것을 보여줄 것이다.

• 한방비만학회지
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• 제8권1호
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• pp.89-99
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• 2008

Objectives Obesity is not only a matter of accumulation of adipose tissue but also a projection of self-cognition. This study examined the association between low self-esteem and visceral obesity; visceral adipose tissue (VAT) and visceral adipose tissue /subcutaneous adipose tissue ratio (VSR). Methods This cross-sectional study was performed in pre-menopausal obese(BMI $\geq\;25\;kg/m^2$) women in Seoul, from 2007 to 2008 (n=54). Simple anthropometry including BMI and waist circumference and Computed Tomography (CT) including VAT and VSR were done. To measure self-esteem, Rosenberg self-esteem scale (SES) questionnaire was administered. Subjects were given written consent and this study was performed under the permission of institutional review board of Kyung-Hee East-west Neo Medical Center. Results There was a significant relationship self esteem (SES score) with visceral obesity (VAT and VSR). 1. SES was correlated with VAT (r=-0.377, p<0.01) and VSR (r= -0.400, p<0.01) significantly by Pearson Correlation. 2. VAT and VSR could be predicted from SES by Simple linear regression. VAT = -1.701 ${\times}$ (SES score) +161.191 ($R^2$=0.142) VSR = -1.09${\times}$$10^{-2}$ ${\times}$ (SES score) +0.858 ($R^2$=0.160) Conclusions This study proves that low self-esteem might contribute to visceral obesity in Korean pre-menopausal obese women. Self-esteem and psychological factor should be considered in treatment of visceral obesity in adult-women.

• 한국광학회:학술대회논문집
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• 한국광학회 2007년도 동계학술발표회 논문집
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• pp.135-136
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• 2007

• 한국통계학회:학술대회논문집
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• 한국통계학회 2005년도 춘계 학술발표회 논문집
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• pp.191-196
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• 2005

Knowing the time of the process change could lead to quicker identification of the responsible special cause and less process down time, and it could help to reduce the probability of incorrectly identifying the special cause. In this paper, we propose a MLE of the process change point when control charts with the fixed sampling rate (FSR) scheme or the variable sampling rate (VSR) scheme monitor a process to detect changes in the process mean and/or variance of a normal quality variable.

• Journal of international Conference on Electrical Machines and Systems
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• 제3권4호
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• pp.433-445
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• 2014

Single phase voltage source converter (VSC) is an important power electronic converter (PEC), including single-phase voltage source inverter (VSI), single-phase voltage source rectifier (VSR), single-phase active power filter (APF) and single-phase grid-connection inverter (GCI). As the fundamental part of large scale PECs, single-phase VSC has a wide range of applications. In the paper, as first, on the basis of the concept of the discontinuous pulse-width modulation (DPWM) for three-phase VSC, a new DPWM of single-phase VSR is presented by means of zero-sequence component injection. Then, the transformation from stationary frame (abc) to rotating frame (dq) is designed after reconstructing the other orthogonal current by means of one order all-pass filter. Finally, the presented DPWM based single-phase VSR is established analyzed and simulated by means of MATLAB/SIMULINK. In addition, the DPWMs presented by D. Grahame Holmes and Thomas Lipo are discussed and simulated in brief. Obviously, the presented DPWM can also be used for single-phase VSI, GCI and APF. The simulation results show the validation of the above modulation algorithm, and the DPWM based single-phase VSR has reduced power loss and increased efficiency.

• 품질경영학회지
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• 제32권4호
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• pp.252-264
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• 2004

Variable sampling Interval (VSI) control charts vary the sampling interval according to value of the control statistic while the sample size is fixed. It is known that control charts with 2-state VSI scheme, which uses only two sampling intervals, give good statistical properties. Variable sample size (VSS) control charts vary the sample size according to value of the control statistic while the sampling interval is fixed. In the VSS scheme no optimal results are known for the number of sample sizes. It is also known that the variable sampling rate (VSR) $\bar{X}$ control chart with 2-state VSS and 2-state VSI scheme leads to large improvements In performance over the fixed sampling rate (FSR) $\bar{X}$ chart, but the optimal number of states for sample size Is not known. In this paper, the VSR Χ charts with multi-state VSS and 2-state VSI scheme are designed and compared to 2-state VSS and 2-state VSI scheme. The multi-state VSS scheme is considered to, achieve an additional improvement by switching from the 2-state VSS scheme. On the other hand, the multi-state VSI scheme is not considered because the 2-state scheme is known to be optimal. The 3-state VSS scheme improves substantially the sensitivity of the $\bar{X}$ chart especially for small and moderate mean shifts.

• Journal of Yeungnam Medical Science
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• 제31권1호
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• pp.9-12
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• 2014

Postinfarction ventricular septal rupture (VSR) is a rare but fatal complication of acute myocardial infarction. In many cases, postinfarction VSR leads to hemodynamic instability and urgent surgical treatment is necessary. Here we describe a case of a patient with right ventricular (RV) dysfunction caused by acute RV infarction and with cardiogenic shock, whose condition improved after development of postinfarction VSR, but the patient died after corrective surgery.

• 품질경영학회지
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• 제33권4호
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• pp.117-122
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• 2005

Variable sampling rate(VSR) scheme varies the sampling rate for the current sample depending on the previous value of the control statistic. In this paper, we propose EWMA control charts with variable parameter(VP) scheme, which allows both the sample rate(the sample size or the sampling interval) and the weight to vary. We investigate the effectiveness of the VP scheme relative to the fixed parameter(FP) scheme and the VSR scheme in EWMA control charts. It is shown that using the VP scheme gives some improvements to the ability in detecting small and moderate shifts in the process normal mean.