Korea University

About: Korea University is a education organization based out in Seoul, South Korea. It is known for research contribution in the topics: Population & Catalysis. The organization has 39756 authors who have published 82424 publications receiving 1860927 citations. The organization is also known as: Bosung College & Bosung Professional College.

The reliability and validity of the Korean version of the Epworth sleepiness scale.

Abstract: The Epworth sleepiness scale (ESS) is widely used to measure the subject's average sleep propensity across those different situations in daily life, particularly in patients with sleep-disordered breathing The purposes of this study were to test the hypothesis that the Korean version of the ESS (KESS) is valid and evaluate its usefulness We developed the KESS, which involved translating into Korean and then translating back into English to check its accuracy A total of 273 participants (181 obstructive sleep apnea (OSA)—37 mild, 61 moderate, 83 severe, 32 simple snoring and 60 normal) were included in this study All subjects completed the overnight polysomnograph and 53 of the total subjects were randomly selected for a retest with the questionnaire approximately 2∼4 weeks later The associations between KESS and the degree of OSA were examined through ANCOVA, adjusted for age, sex and BMI The total score and each item's score of KESS in patients with OSA were significantly higher than subjects with normal controls (p < 001) As the severity of OSA increased, the KESS showed significantly increasing patterns (p for trend <001) The KESS in patient groups showed good internal consistency (Cronbach's α = 090) and test–retest reliability (r = 078 to 093) The KESS is a reliable and valid tool for screening patients with daytime sleepiness in Korea

A meshfree method based on the local partition of unity for cohesive cracks

Abstract: We will present a meshfree method based on the local partition of unity for cohesive cracks. The cracks are described by a jump in the displacement field for particles whose domain of influence is cut by the crack. Particles with partially cut domain of influence are enriched with branch functions. Crack propagation is governed by the material stability condition. Due to the smoothness and higher order continuity, the method is very accurate which is demonstrated for several quasi static and dynamic crack propagation examples.