• ETRI Journal
• /
• 제45권6호
• /
• pp.1007-1021
• /
• 2023

Stroke is the leading cause of permanent disability in adults, and it can cause permanent brain damage. According to the World Health Organization, 795 000 Americans experience a new or recurrent stroke each year. Early detection of medical disorders, for example, strokes, can minimize the disabling effects. Thus, in this paper, we consider various risk factors that contribute to the occurrence of stoke and machine learning algorithms, for example, the decision tree, random forest, and naive Bayes algorithms, on patient characteristics survey data to achieve high prediction accuracy. We also consider the semisupervised self-training technique to predict the risk of stroke. We then consider the near-miss undersampling technique, which can select only instances in larger classes with the smaller class instances. Experimental results demonstrate that the proposed method obtains an accuracy of approximately 98.83% at low cost, which is significantly higher and more reliable compared with the compared techniques.

• 한국해안·해양공학회논문집
• /
• 제27권1호
• /
• pp.38-49
• /
• 2015

지진해일에 대한 기존의 연구는 이차원 Boussinesq 모형과 Solitary wave에 기초한 수치해석이 그 주류를 이룬다. 최근 Solitary wave에 의한 처오름 높이가 관측치를 하회한다는 인식에 기초하여 지진해일 내습전 해안선이 전진하는 현상의 모의가 가능한 Leading Depression N (LDN) Wave가 제시되었으며 이에 기초하는 경우 보다 정확한 모의가 가능한 것으로 보고된 바 있다. 이러한 성과에도 불구하고 수리모형 실험의 경우 안정적인 Leading Depression N (LDN) Wave의 구현에 상당한 어려움을 겪어왔다. 이러한 이차원 Boussinesq 모형과 삼차원 수리모형 실험에서의 상충된 결과는 이차원 Boussinesq 계열 파랑 모형 유도과정에서 수행되는 파랑의 비선형성과 분산성이 균형을 이룬다는 가정과 이로 인해 다소 과소하게 평가된 분산성에 기인하는 것으로 판단된다. 이러한 인식에 기초하여 본고에서는 삼차원 수치수조에서 비교적 안정적인 LDN 파형의 조파가 가능한 수정 조파기법과 Navier Stoke 파랑모형에 기초하여 Hybrid Breaker의 지진해일에 의한 처오름 저감효과를 수치 해석하였다. 파랑모형의 검증은 불규칙 파랑을 대상으로 기 수행된 수리모형 실험결과를 토대로 진행되었으며, 그 결과 비교적 근접한 처오름 높이를 얻을 수 있었다. 세 개의 유수실과 전면 경사면으로 구성된 Hybrid Breaker의 경우 일반 경사제에 비해 H = 5m의 경우 약 13%, H = 6 m의 경우 10%정도의 처오름 저감 효과를 지니는 것으로 모의되었다.

• 재활간호학회지
• /
• 제9권1호
• /
• pp.15-24
• /
• 2006

Purpose: This study was to explore the cognitive function of Korean-Chinese stroke patient in China. Method: The study sample was 100 who were possible to communicate and agreed. The data were collected from one Brain's hospital at Yanji in China and by trained nurse from December 12, 2005 to April 28, 2006. The measurement tools were Digit span, Trail making, and MMSE-K. The data were analysed by SPSS Win 11.5 using frequency, t-test, ANOVA, and Pearson's correlation coefficients. Results: The mean score of DSF was 5.07, 3.42 of DSB, 161.37 of TMA, 229.28 of TMB, 22.64 of MMSE-K. There was a significant difference in DSF (F=6.35, p=.001), DSB (F=6.10, p=.001), TMA (F=3.53, p=.018), TMB (F=3.26, p=.025), MMSE-K score (F=12.97, p=.000) according to age, and DSF (F=6.67, p=.000), DSB (F=6.01, p=.000), TMA (F=5.82, p=.001), TMB (F=6.23, p=.001), and MMSE-K score (F=13.02, p=.000) according to educational level, and DSF (F=5.35, p=.006), DSB (F=3.16, p=.047), TMA (F=3.30, p=.041), TMB (F=3.42, p=.037), and MMSE-K score (F=4.95, p=.009) according to duration of disease, and DSB (F=3.54, p=.018), and MMSE-K (F=6.05, p=.001) according to frequencies of hospitalization. There was high correlation between DSF and DSB (r=.581, p=.000), TMA and TMB (r=.936, p=.000), MMSE-K and DSF (r=.579, p=.000), MMSE-K and DSB (r=.591, p=.000), DSF and TMA (r=.727, p=.000), and DSF and TMB (r=.721, p=.000). Conclusion: The cognitive evaluation score of Korean-Chinese stroke patients in China was in normal limit. The age, educational level, duration of disease and income were significant demographic characteristic affecting cognitive function. Further study need to compare the cognitive function of Korean-Chinese stoke patients in China and stoke patients in Korea.

• 재활복지
• /
• 제18권4호
• /
• pp.221-235
• /
• 2014

최근 급속한 인구 고령화로 인해 뇌졸중의 발생빈도가 증대되고 있으며, 후천적 장애의 주요 발생요인이 되고 있다. 본 연구는 뇌졸중의 후유증으로 인한 장애를 극복하기 위한 재활 과정에서 사용되는 보조장비인 체위제어용 자세변환기에 관한 것이다. 본 논문에서는 국내와 일본의 자세변환기 용품을 조사하여 기능과 용도에 따라 분류와 비교를 수행하였고, 와상체위를 제어하기 위해 스마트 고기능 자세변환 시스템의 설계방식을 제안하였다. 이는 욕창방지 튜브와 체위 경사동작 튜브를 통합한 매트리스 동작을 갖도록 고안된 것이다. 또한 스마트 기능을 추가하여 현재 기기 상태의 모니터링과 기본자세변경, 교대부양 및 체위제어의 무선 기능의 수행이 가능하도록 설계하였다. 시스템제어 하드웨어는 3개의 주요부, 즉 센서 검출부, 모터구동 제어부, 블루투스(Bluetooth) 통신을 위한 시스템제어부로 구성되어 있다. 결과로서, 본 연구에 의해 설계된 시스템이 최근 인터넷 정보화 기술의 적용분야인 IoT(Internet of Things) 기술이 접목된 고기능 스마트 자세변환장치로 실용화 될 수 있음을 확인하였다.

• 대한의용생체공학회:의공학회지
• /
• 제2권2호
• /
• pp.89-102
• /
• 1981

The recirculating flows which occur in the prosthetic heart valve have been known to cause several diseases in the human body. And the recent studies show that the shear stress at the wall of the artery is also very important factor in the formation of thrombus. And many studies knave been devoted in obtaining more information about the blood flow through the prosthetic heart valve. In this Paper, the steady axisymmetric flow through the Disc-Type Heart Valve is studied by using the numerical method. The geometry of the Disc-Type Heart Valve is simplified, and the flow is assumed to be steady axisymmetric flow. The vorticity transport equation derived from the Wavier-Stoke's equation is used as the governing equation, and the explicit finite difference method is used to obtain the steady state solution. The results for several Reynolds numbers show that the recirculating flow becomes large as the Remolds number increases. Furthermore, it can be shown that the magnitudes of the vorticity and the stresses are also increased with the Reynolds number, but there is only a little change in their configurations of distribution and in their positions of maximum values.

• 근관절건강학회지
• /
• 제19권2호
• /
• pp.107-119
• /
• 2012

Purpose: This study was conducted to extract international classification of functioning, disability, and health (ICF) core sets for measuring functional status in acute stroke patients, and to evaluate clinical applicability of the core sets. Methods: A set of 22 ICF items on functional status in acute stroke patients were extracted from the Korean general ICF core sets and ICF core sets for stroke patients. The extracted ICF functional items were assessed at the time of admission and discharge among 100 stroke patients who were admitted in a university hospital. Results: Comparing to functional status at admission of acute stroke patients, the overall functional status at discharge was improved. However, functions on defecation, skin protection, and relationship with immediate family at the time of discharge were not significantly changed. Conclusion: The set of ICF functional items identified in this study may be reliable and valid to assess acute stoke patients' body functions, activities and participation and environmental factors in the holistic and comprehensive nursing context. Nursing interventions on bowel elimination and skin protection for acute stroke patients need to be developed.

• 대한조선학회논문집
• /
• 제41권6호
• /
• pp.24-32
• /
• 2004

The effects of guide vanes and tip clearances on the characteristics nf axial flow fans are investigated both computationally and experimentally. Performance test of fans carried out in full scale shows considerable effects of tip clearance between rotor tip and duct on the characteristics of fans. The tested results are compared with the computation based on the finite volume method to solve the Navier-Stoke equations with $textsc{k}$-$\varepsilon$ turbulence model. The comparison shows good agreements between experimental and computational results. In addition, the effects of shape of guide vanes are numerically studied. The results show that increased volume of separated region around the guide vane reduces the recovery of tangential component of kinetic energy in the wake, resulting in loss of efficiency

• Journal of Acupuncture Research
• /
• 제20권2호
• /
• pp.161-172
• /
• 2003

Objective : This study was designed to investigate the relation between the angiotensin converting enzyme(ACE) gene polymorphism and stroke in the Korean population. Methods : This study was carried out on 58 stroke patients who were hospitalized in the department of acupuncture & moxibustion, college of Oriental Medicine, Kyung-Hee University and 61 healthy control subjects. Blood samples from all subjects were obtaind for DNA extration. The extracted DNA was amplified by polymerase chain reaction(PCR). PCR products were visualized by 2% agarose gel electrophoresis. Results : The sub-genotypes of ACE gene were II homozygotes, ID heterozygotes, DD homozygotes. While the distribution of ACE polymorphism in control subjects was 31%, 51%, 18%, the distribution of it in stoke patients was 33%, 52%, 16%(II, ID, DD). Thus, there was no significant different between the control and stroke groups. Conclusions : we conclude that there is no significant association between ACE gene polymorphism and storke in Korean papulation. However, the findings of this study need to be confirmed in large patients and further studies. Additional epidemiologicallly based studies of the effects and relationship between ACE or other genes and lifesyles with regard to stroke required.

• Journal of Korean Biological Nursing Science
• /
• 제16권1호
• /
• pp.52-59
• /
• 2014

Purpose: The purpose of this study was to investigate antioxidant capacity and relating factors including gender, obesity, lifestyle factors, and nutrient intake in chronic stroke patients. Methods: A total of 188 chronic stroke patients who visited a medical center in Seoul participated in the study. A structured questionnaire was used to assess their clinical characteristics and lifestyles. Blood samples were collected for ferric reducing ability of plasma (FRAP) for antioxidant capacity. Dietary intake of the patients were obtained for 2 days by 24 hours recall method. Results: The mean FRAP was $392.0{\mu}mol/L$. According to the hierarchical multiple regression analysis, the factors related to high FRAP were male sex (p=.036), alcohol drinking (p=.013), and calorie intake deficiency (p=.005). Conclusion: We found that antioxidant capacity was related to lifestyle factors including alcohol drinking, and calorie intake in chronic stroke patients. A tailored strategy is needed to increase antioxidant capacity according to gender and lifestyles in the chronic phase of stoke patients.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2010년 춘계학술대회논문집
• /
• pp.195-200
• /
• 2010

Numerical investigation was conducted to study the effects of after-body configurations and nozzle lip on the PIFS(Plume Induced Flow Separation) and eat flux to the base face. Two dimensional and axi-symmetric non-equilibrium Navier-Stoke's solver with $k-{\omega}$ SST turbulence model was used to solve the launching vehicle type configuration with propulsive jet. The experimental result of Robert J. McGhee was compared with our computational results for code validation. Three types of the after-body configurations (Straight, Boat-tail, Flare type) were simulated for this study. And the nozzle lip effect was studies using the three types of base configurations same simulation conditions. As a result of numerical investigations, higher pressure ratio condition and boat-tail after-body configuration caused severe PIFS phenomenon but the flare type after-body configuration and low pressure ratio suppressed PIFS. Flare type after-body configuration and low pressure ratio case reduced heat flux to base face. The nozzle lip dispersed the heat flux widely along the base face and the nozzle lip.