• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
• /
• pp.120-122
• /
• 2006

The paper concerns the hybrid optimization of fuzzy inference systems that is based on Hierarchical Fair Competition-based Parallel Genetic Algorithms (HFCGA) and information data granulation. The granulation is realized with the aid of the Hard C-means clustering and HFCGA is a kind of multi-populations of Parallel Genetic Algorithms (PGA), and it is used for structure optimization and parameter identification of fuzzy model. It concerns the fuzzy model-related parameters such as the number of input variables to be used, a collection of specific subset of input variables, the number of membership functions, the order of polynomial, and the apexes of the membership function. In the hybrid optimization process, two general optimization mechanisms are explored. Thestructural optimization is realized via HFCGA and HCM method whereas in case of the parametric optimization we proceed with a standard least square method as well as HFCGA method as well. A comparative analysis demonstrates that the proposed algorithm is superior to the conventional methods.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.204-206
• /
• 2007

In this study, we introduce the optimization method of fuzzy inference systems that is based on Hierarchical Fair Competition-based Parallel Genetic Algorithms (HFCGA) and information data granulation, The granulation is realized with the aid of the Hard C-means clustering and HFCGA is a kind of multi-populations of Parallel Genetic Algorithms (PGA), and it is used for structure optimization and parameter identification of fuzzy model. It concerns the fuzzy model-related parameters such as the number of input variables to be used, a collection of specific subset of input variables, the number of membership functions, the order of polynomial, and the apexes of the membership function. In the optimization process, two general optimization mechanisms are explored. The structural optimization is realized via HFCGA and HCM method whereas in case of the parametric optimization we proceed with a standard least square method as well as HFCGA method as well. A comparative analysis demonstrates that the proposed algorithm is superior to the conventional methods. Particularly, in parameter identification, we use the UNDX operator which uses multiple parents and generate offsprings around the geographic center off mass of these parents.

• 보건의료산업학회지
• /
• 제14권1호
• /
• pp.15-30
• /
• 2020

Objectives: This study investigated outpatient health care satisfaction and influential factors using data from the "2018 Health Care Experience Survey". Methods: Data on 6,705 participants in the Health Care Experience Survey were statistically examined using a t-test, ANOVA, and multiple regression analysis. Results: First, the level of satisfaction among outpatients was generally positive, and satisfaction among older people was high. Second, the significant factors of outpatient overall satisfaction were gender, consultation time, waiting time, reason for choosing institution, satisfaction with doctors, nurses, institutions, and the therapeutic result. Third, influential factors of intention to recommend were education, institution type, reason for choosing institution, satisfaction with doctors, nurses, institutions, and the therapeutic result. Conclusions: In order to improve the overall satisfaction of outpatients, the treatment method should be improved. For example, the doctor should devote more time for and engage in sufficient conversation with the patient, the nurse should be polite, and patients should be given easy-to-understand explanations.

• 보건의료산업학회지
• /
• 제14권1호
• /
• pp.161-176
• /
• 2020

Objectives: The purpose of this study was to investigate the effects of health status and health behaviors on health-related quality of life in Korean adults. Methods: The study was based on the 2017 National Health and Nutrition Survey. Of the total 8,127 people, 5,780 (71.1%) participated: 2,553 (44.2%) were male and 3,227 (55.8%) were female. The variables for this study were demographic factors, disease count, subjective health status, health behaviors, and health-related quality of life (measured by the EQ-5D Index). Results: After analysis, the statistically significant factors associated with health-related quality of life were gender, age, income, education, daytime health status, number of comorbidities (6 or more) and stress. Conclusions: Seven demographic factors have been identified as having a significant impact on health-related quality of life, categorized by model, gender, age and income. Therefore, it is possible that quality of life can be improved through proactive management and by improving subjective health status and health behaviors while in considering of demographic and sociological factors by providing indicators as per gender and age.

• Korean Journal of Radiology
• /
• 제23권6호
• /
• pp.581-597
• /
• 2022

Left ventricular (LV) wall thickening, or LV hypertrophy (LVH), is common and occurs in diverse conditions including hypertrophic cardiomyopathy (HCM), hypertensive heart disease, aortic valve stenosis, lysosomal storage disorders, cardiac amyloidosis, mitochondrial cardiomyopathy, sarcoidosis and athlete's heart. Cardiac magnetic resonance (CMR) imaging provides various tissue contrasts and characteristics that reflect histological changes in the myocardium, such as cellular hypertrophy, cardiomyocyte disarray, interstitial fibrosis, extracellular accumulation of insoluble proteins, intracellular accumulation of fat, and intracellular vacuolar changes. Therefore, CMR imaging may be beneficial in establishing a differential diagnosis of LVH. Although various diseases share LV wall thickening as a common feature, the histologic changes that underscore each disease are distinct. This review focuses on CMR multiparametric myocardial analysis, which may provide clues for the differentiation of thickened myocardium based on the histologic features of HCM and its phenocopies.

• Investigative Magnetic Resonance Imaging
• /
• 제18권4호
• /
• pp.314-322
• /
• 2014

배경: 심장의 이완기능 이상은 비대성심근증 환자에서 흔히 발견되는 문제이다. 본 연구는 비대성심근증 환자의 심장 이완기능을 평가하는 데 있어, 승모판과 폐정맥의 유속을 이용한 MRI의 역할을 알아보고자 하였다. 방법과 결과: 승모판과 폐정맥의 유속을 이용한 위상차 MRI와 심초음파검사가 59명 (남:여 = 44:15, 평균 연령 = 51세)의 비대성심근증 환자에서 시행되었다. 49명의 환자가 심초음파검사에서 다양한 정도의 심장 이완기능 이상을 보였다; grade 1 (20명), grade 2 (27명), and grade 3 (2명). MRI로 계산한 승모판 유속인자들 (E, A, E/A ratios)은 심초음파검사로 구한 동일 인자들과 양의 상관관계를 보였다 (Pearson's r values = 0.47, 0.60, 0.75 for E, A, E/A, respectively, all P < 0.001). MRI로 폐정맥 유속정보를 이용하는 경우, pseudo-normalized pattern (8명)이 정상 충만 양상(filling pattern) (17명)과 구분될 수 있었고, 이들을 이용하여 이완기능 정도를 평가를 하는 경우, 심장 MRI가 심초음파검사와 중등도의 일치도를 보였다 (kappa value = 0.45, P < 0.001). 결론: 비대성심근증 환자에서 위상차 MRI를 이용한 심장 이완기능 평가는 임상적으로 적용 가능한 방법이며, 폐정맥 유속 분석을 추가하는 경우, 정상과 pseudo-normal을 구분하는데 유용하다.

• 한국임상수의학회지
• /
• 제26권4호
• /
• pp.362-366
• /
• 2009

비대심장근육병증은 고양이에서 가장 흔히 발생하는 심장근육병증의 한 종류이다. 원인은 명확하지 않지만, 어떤 예에서는 유전적인 원인이 작용하는 것으로 생각된다. 혈전색전증은 심장근육병증이 있는 고양이에서 심각한 합병증을 야기한다. 서울대학교 동물병원에 구토 이후에 양쪽 후지마비를 주소로 내원한 2마리의 고양이에서, 내원 당시 고양이는 침울한 상태였고, 양쪽 후지는 청색증을 보였고 냉감과 통증을 나타내었다. 심잡음이 두 마리 모두에서 청취되었다. 일반 촬영과 심초음파 평가를 통해 비대심장근육병증을 진단하였다. 대동맥 분기부 혈전색전증을 복부 초음파 검사를 통해 확인하였다. 두 고양이 모두 폐사하였으며, 그 중 한 마리에서는 부검을 통해 비대심장근육병증 및 안장모양 혈전을 확인하였다.

• Preventive Nutrition and Food Science
• /
• 제11권1호
• /
• pp.42-47
• /
• 2006

This study investigated the effects of mulberry leaf extract on lipid metabolism in rats fed a high cholesterol diet. Sprague-Dawley male rats weighing $100{\pm}10g$ were randomly assigned either to one of two normal diet groups, with (NE group) or without (N group) mulberry extract, or one of four high cholesterol groups containing 1% cholesterol and various levels of dietary mulberry leaf extract. The rats fed high cholesterol diets were subdivided into 4 groups according to level of mulberry extract; Mulberry extract free group (HC group), 0.8% mulberry leaf extract group (HCL group), 1.6% mulberry leaf extract (HCM group) and 3.2% mulberry leaf extract (HCH group). The rats were fed their respective diets ad libitum for 4 weeks. The levels of serum triglyceride, total cholesterol and LDL-cholesterol of the HC group were higher than mulberry leaf extract supplemented groups. In contrast, the levels of serum HDL-cholesterol in groups supplemented with mulberry leaf extract were significantly lower than that of HC group. Hepatic total lipids, triglycerides, and cholesterol were significantly higher in the high cholesterol groups compared to those of the normal group, but were lower in the HCL, HCM and HCH groups than in the HC group. HMG-CoA reductase activity was significantly decreased in the HC and HCL groups compared to the normal and NE groups. However, the activities in the HCM and HCH group were similar to that of the normal group. The activity of acyl-CoA-cholesterol acyl transferase (ACAT) was increased in high cholesterol groups compared to the normal group. However, the activity was lower for all of the high cholesterol groups fed mulberry leaf extracts, and was lowest for the highest supplemented group (HCH), with no significantly difference from the normal group. In conclusion, the reduction in serum and hepatic lipid composition by mulberry leaf extract may be due to its modulation of HMG-CoA reductase and ACAT activities.

• 대한환경공학회지
• /
• 제35권2호
• /
• pp.144-150
• /
• 2013

본 연구에서는 고급산화공정에서 촉매제로 사용되는 산화철 나노입자를 세라믹 멤브레인 표면에 부착하여 오존 산화 공정과 연계 처리가 가능한 반응성 세라믹 멤브레인을 합성하고, 이를 이용한 하이브리드 세라믹 멤브레인 시스템(일원화된 오존-멤브레인 시스템)을 통해 자연유기화합물에 의한 막 오염 제어 특성을 평가하였다. 디스크 형태의 알루미나 정밀여과 및 한외여과 세라믹 멤브레인에 소결법을 사용하여 산화철 나노입자를 부착하였으며, 산화철 나노입자 양에 따른 반응성 세라믹 멤브레인의 특성을 분석하였다. 주사전자현미경(SEM) 분석을 통해 세라믹 멤브레인 표면 위에 산화철 나노입자 층이 형성되었음을 확인할 수 있었고, 부착된 산화철 나노입자의 크기는 대략 50 nm임을 확인할 수 있었다. 반응성 세라믹 멤브레인과 기존 세라믹 멤브레인의 막 투과 성능(Pure water permeability) 비교 실험 결과 큰 차이를 보이지 않았는데, 이는 반응성 세라믹 멤브레인 표면에 형성된 산화철 나노입자 층이 멤브레인의 투과 유량에 큰 영향을 끼치지 않음을 확인할 수 있었다. 하이브리드 세라믹 멤브레인 시스템을 통한 자연유기화합물의 막 오염(Fouling) 및 막 오염 회복(Fouling recovery) 실험을 통해, 반응성 세라믹 멤브레인을 사용한 시스템이 산화철 나노입자와 오존과의 반응을 통해 생성된 수산화라디칼이 보다 효율적으로 자연유기화합물을 분해하여 막 오염을 저감하는 것을 확인할 수 있었다. 또한 원수와 처리수 내의 자연유기화합물 분석을 통해, 반응성 세라믹 멤브레인 시스템이 보다 효과적으로 자연유기화합물의 방향성 성분 감소, 고분자량 비율 감소, 소수성 성분 감소 등을 통해 막 오염을 제어함을 확인할 수 있었다.

• Korean Journal of Radiology
• /
• 제22권7호
• /
• pp.1054-1065
• /
• 2021

Objective: We implemented a novel resectable myocardial model for mock myectomy using a hybrid method of three-dimensional (3D) printing and silicone molding for patients with apical hypertrophic cardiomyopathy (ApHCM). Materials and Methods: From January 2019 through May 2020, 3D models from three patients with ApHCM were generated using the end-diastolic cardiac CT phase image. After computer-aided designing of measures to prevent structural deformation during silicone injection into molding, 3D printing was performed to reproduce anatomic details and molds for the left ventricular (LV) myocardial mass. We compared the myocardial thickness of each cardiac segment and the LV myocardial mass and cavity volumes between the myocardial model images and cardiac CT images. The surgeon performed mock surgery, and we compared the volume and weight of the resected silicone and myocardium. Results: During the mock surgery, the surgeon could determine an ideal site for the incision and the optimal extent of myocardial resection. The mean differences in the measured myocardial thickness of the model (0.3, 1.0, 6.9, and 7.3 mm in the basal, midventricular, apical segments, and apex, respectively) and volume of the LV myocardial mass and chamber (36.9 mL and 14.8 mL, 2.9 mL and -9.4 mL, and 6.0 mL and -3.0 mL in basal, mid-ventricular and apical segments, respectively) were consistent with cardiac CT. The volume and weight of the resected silicone were similar to those of the resected myocardium (6 mL [6.2 g] of silicone and 5 mL [5.3 g] of the myocardium in patient 2; 12 mL [12.5 g] of silicone and 11.2 mL [11.8 g] of the myocardium in patient 3). Conclusion: Our 3D model created using hybrid 3D printing and silicone molding may be useful for determining the extent of surgery and planning surgery guided by a rehearsal platform for ApHCM.