신뢰도를 요구하는 임베디드 시스템에서의 저전력 태스크 스케쥴링

김경훈,김유나,김종,Kim, Kyong Hoon,Kim, Yuna,Kim, Jong 대한임베디드공학회 2008 대한임베디드공학회논문지 Vol.3 No.1

In this paper, we provide an adaptive power-aware checkpointing scheme for fixed priority-based DVS scheduling in dependable real-time systems. In the provided scheme, we analyze the minimum number of tolerable faults of a task and the optimal checkpointing interval in order to meet the deadline and guarantee its specified reliability. The energy-efficient voltage level at a fault arrival is also analyzed and used in the recovery of the faulty task.

요양급여적정성 평가자료를 이용한 예방적 항생제 사용과 수술부위 감염 발생의 관련성 연구

김경훈,박춘선,장진희,김남순,이진서,최보람,이병란,이규덕,김선민,염선아,Kim, Kyoung-Hoon,Park, Choon-Seon,Chang, Jin-Hee,Kim, Nam-Soon,Lee, Jin-Seo,Choi, Bo-Ram,Lee, Byung-Ran,Lee, Kyoo-Duck,Kim, Sun-Min,Yeom, Seon-A 대한예방의학회 2010 예방의학회지 Vol.43 No.3

Objectives: To examine the prophylactic antibiotic use in reducing surgical site infection. Methods: This was a retrospective study for patients aged 18 years and older who underwent gastrectomy, cholecystectomy, colectomy, cesarean section and hysterectomy. The data source was quality assessment data of the Health Insurance Review & Assessment Service gathered from medical records of 302 national hospitals. Prophylactic antibiotic use was defined as: timely antibiotic administration or inappropriate antibiotic selection. We performed hierarchical logistic regression to examine the association between prophylactic antibiotic use and surgical site infection with adjustment for covariates. Results: The study population consisted of 16 348 patients (1588 gastrectomies, 2327 cholecystectomies, 1,384 colectomies, 3977 hysterectomies and 7072 cesarean sections) and surgical site infection was identified in 351 (2.1%) patients. The rates of timely antibiotic administration and inappropriate antibiotic selection varied according to procedures. Cholecystectomy patients who received timely prophylactic antibiotic had a significantly reduced risk of surgical site infection compared with those who did not receive a timely prophylactic antibiotics (OR 0.64, 95% CI=0.50-0.83), but no significant reduction was observed for other procedures. When inappropriate prophylactic antibiotics were given, the risk of surgical site infection significantly increased: 8.26-fold (95% CI=4.34-15.7) for gastrectomy, 4.73-fold (95% CI=2.09-10.7) for colectomy, 2.34-fold (95% CI=1.14-4.80) for cesarean section, 4.03-fold (95% CI=1.93-8.42) for hysterectomy. Conclusions: This study examines the association among timely antibiotic administration, inappropriate antibiotic selection and surgical site infection. Patients who received timely and appropriate antibiotics had a decreased risk of surgical site infection. Efforts to improve the timing of antibiotic administration and use of appropriate antibiotic are needed to lower the risk of surgical site infection.

Sol-Gel 법을 이용한 칼슘-알루미네이트계 전자화물 박막의 제조와 특성

김경훈,박주석,채재홍,서원선,소성민,김태관,김형순,이병하,Kim, K.H.,Park, J.S.,Chae, J.H.,Seo, W.S.,So, S.M.,Kim, T.K.,Kim, H.S.,Lee, B.H. 한국결정성장학회 2010 한국결정성장학회지 Vol.20 No.6

Sol-gel법을 적용하여 $12CaO{\cdot}7Al_2O_3$(C12A7) 전자화물 박막을 제조하기 위해 CaO-$Al_2O_3$ sol을 제조하여 dip 코팅법을 적용하여 quartz 기판에 박막을 형성하였으며 열처리를 통해 C12A7의 박막을 제조하였다. C12A7 상의 형성 $800^{\circ}C$에서 시작되었고 $1,200^{\circ}C$ 온도에서 1시간 열처리를 통해 치밀화된 박막을 제조할 수 있었다. 제조된 C12A7 박막은 부도체였지만 수소 환원 분위기 열처리를 통해 전기전도도를 나타내기 시작했으며 $1,200^{\circ}C$ 48시간 열처리 시 120 S/cm의 전기전도도를 나타내었다. The Calcium-aluminate electride thin films on the quartz substrates was coated by sol-gel process. The crystallization of the C12A7 thin film was observed at $800^{\circ}C$ and high density C12A7 thin film was achieved on heat treatment at $1,200^{\circ}C$ for 1 hour. The reduction heat treatment of C12A7 thin film could be converted from insulator to conductor and the electrical conductivity was 120 S/cm in the C12A7 thin film heat treated at $1,200^{\circ}C$ with $H_2$ gas for 48 hours.

고속 웹 이송속도 및 복잡한 롤 패턴 형상을 고려한 R2R공정에서의 잉크전달 특성 해석

김경훈,김소희,나양,Kim, Kyung-Hun,Kim, So-Hee,Na, Yang 한국반도체디스플레이기술학회 2010 반도체디스플레이기술학회지 Vol.9 No.2

Ink transfer process from the printing roll to the moving web was investigated using a CFD technique for the application in R2R printed electronics. In line with the requirement that the web handling speed needs to be increased further for the cost competitiveness, the effects of web moving velocity with relatively complex roll patterns were analyzed. To make the present analysis more realistic, the numerical geometry and the ink properties were selected to match those of the real printing production system. Our numerical results showed that both web handling speed and complex printing-roll patterns influenced the shape of the transferred ink. As the web moving speed approaches towards 30mpm, a significant distortion of the shape of the transferred ink occurred. In the range of pattern width smaller than 100 microns, a phase distortion was also found to occur in all the printing-roll patterns considered in the present work but the ratio of the phase distortion to the line width gets smaller as the width becomes smaller. Thus, the web handling speed and the shape of printing-roll pattern will be important elements for the better printing quality under 100 micron line width range.

선형 사진트리의 선형이동을 위한 상수시간 RMESH 알고리즘

김경훈,우진운,Kim, Kyung-Hoon,Woo, Jin-Woon 한국정보처리학회 2003 정보처리학회논문지 A Vol.10 No.3

계층적 자료구조인 사진트리는 이진 영상을 표현하는데 매우 중요한 자료구조이다. 사진트리를 메모리에 저장하는 방법 중 선형사진트리 표현 방법은 다른 표현 방법과 비교할 때 저장 공간을 매우 효율적으로 절약할 수 있는 이점이 있기 때문에 사진트리와 관련된 연산의 수행을 위해 선형 사진트리를 사용하는 효율적인 알고리즘 개발에 많은 연구가 진행되어 왔다. 선형이동은 영상을 주어진 거리만큼 이동시키는 연산으로, 영상 처리의 응용에서 중요하게 사용되는 연산에 속한다. 본 논문에서는 RMESH (Reconfigurable MESH) 구조에서 3-차원 n${\times}$n${\times}$n 프로세서를 사용하여 선형 사진트리로 표현된 이진 영상의 선형 이동을 수행하는 효율적인 알고리즘을 제안한다. 이 알고리즘은 n${\times}$n${\times}$n RMESH의 계층구조에서 선형 사진트리의 위치코드들을 효율적으로 전송할 수 있는 기본적인 연산들을 이용함으로써 상수 시간의 시간 복잡도를 갖는다. Quadtree, which is a hierarchical data structure, is a very important data structure to represent binary images. The linear quadtree representation as a way to store a quadtree is efficient to save space compared with other representations. Therefore, it has been widely studied to develop efficient algorithms to execute operations related with quadtrees. The linear translation is one of important operations in image processing, which moves the image by a given distance. In this paper, we present an algorithm to perform the linear translation of binary images represented by quadtrees, using three-dimensional $n{\times}n{\times}n$ processors on RMESH (Reconfigurable MESH). This algorithm has constant-time complexity by using efficient basic operations to route the locational codes of quardtree on the hierarchical structure of n${\times}$n${\times}$n RMESH.

Effects of Agility Training with Kinesio Taping on Muscle Tone, Muscle Strength Lower Extremity and Dynamic Stability in Women Softball Players

김경훈,Hyeonhee Kim 물리치료재활과학회 2021 Physical therapy rehabilitation science Vol.10 No.4

Objective: The aim of this study was to investigate the effect of agility training with kinesio taping (ATKT) on muscle tone, muscle strength lower extremity and dynamic stability of women softball players. Design: Two groups pre-post randomized controlled designMethods: 34 softball players were recruited randomly assigned into the ATKT group and agility training with sham kinesio taping (control group). All subjects performed agility training for 30 min/day, 5 times/week for 4 weeks. The subjects in the ATKT group underwent agility trainingwith kinesio taping on vastus madialis, vastus medialis, rectus femoris, and vastus lateralis where the subects in the control group underwent agility trainingwith sham kinseio taping. Muscle tone was measured using myotonPRO. A Hand dynamometer was used to evaluate muscle strengthening of lower -extremity. Dynamic stability was measured using the side hop test. Results: Muscle tone of lower-extremity was significantly more increased in the ATKT group (mean change 0.39 ± 0.31) than in the control group (mean change 0.19 ± 0.31) (p<0.05). Muscle strength of lower-extremity was significantly more increased in the ATKT group than in the control group (p<0.05). Dynamic stability was significantly more increased in the ATKT group (mean change -1.39 ±0.45) than in the control group (mean change -0.60 ± 0.46) (p<0.05). Conclusions: We confirmed that the benefits that ATKT is effective for increasing in softball players and suggested that knee joint kinesio taping. Also, it was observed improvement of muscle tone, muscle strength and Dynamic stability.

키네시오 테이핑을 병행한 하프 스쿼트 훈련이 일반인의 몸통과 다리 근활성도 및 균형능력에 미치는 영향

김경훈,Kim, Kyung-Hun 대한고유수용성신경근촉진법학회 2022 PNF and Movement Vol.20 No.2

Purpose: The aim of this study was to identify the effects of performing the half squat exercise with Kinesio taping (HSEKT) on trunk and lower extremity muscle activity and balance ability in general university students. Methods: The 32 participants were randomly assigned to either the HSEKT group (half squats with Kinesio taping) or the control group (half squats with sham Kinesio taping). Both groups performed half squats with either Kinesio taping (HSEKT group) or sham Kinesio taping (control group) for 30 min/day, 3 times/week for 6 weeks. The Noraxon mini direct transmission system (DTS) electromyography (EMG) system was used to evaluate trunk and lower extremity muscle activity. BioRescue equipment was used to measure the movement area of the center of pressure with eyes open and eyes closed. The muscle activity of the trunk and lower extremities and the balance ability of all participants were measured before and after the intervention. An independent t-test was used to statistically analyze the pre- and post-intervention EMG and balance ability results. Results: The trunk and lower extremity muscle activity was found to have significantly improved in the HSEKT group and the control group after the intervention (p < 0.05). Also, the balance ability of the HSEKT group differed significantly after 6 weeks of training compared to that of the control group (p < 0.05). Conclusion: The findings of this study show that performing half squats with Kinesio taping had a positive effect on trunk and lower extremity muscle activity and balance ability in general university students.

신이론 신기술 - 반려견 사료개발에 필요한 기호성 평가방법

김경훈,Kim, Gyeong-Hun 한국사료협회 2011 飼料 Vol.48 No.-

방전플라즈마 소결법에 의한 탄화 붕소 세라믹스의 소결 거동 및 기계적 특성

김경훈,채재홍,박주석,김대근,심광보,이병하,Kim, Kyoung-Hun,Chae, Jae-Hong,Park, Joo-Seok,Kim, Dae-Keun,Shim, Kwang-Bo,Lee, Byung-Ha 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.1

[ $B_4C$ ] ceramics were fabricated by spark plasma sintering process and their sintering behavior, microstructure and mechanical properties were evaluated. Relative density of $B_4C$ ceramics could be achieved by spark plasma sintering method reached as high as 99% at lower temperature than conventional sintering method, in addition, without any sintering additives. The mechanical properties of $B_4C$ ceramics could be improved by the heat treatment at $1300^{\circ}C$ during sintering process which can be removed $B_2O_3$ phase from a $B_4C$ powder surface. This improvement results from the formation of a fine and homogeneous microstructure because the grain coarsening was suppressed by the elimination of $B_2O_3$ phase. Particularly, mechanical properties of the specimen experienced the $B_2O_3$ removing process improved over 30% compared with the specimen without that process.

듀얼클러치 변속기의 쉬프트 포크에 관한 피로해석 연구

김경훈,정종규,원종진,정재일,Kim, Kyounghoon,Jeong, Jongkyu,Won, Jongjin,Jeong, Jayil 한국자동차안전학회 2012 자동차안전학회지 Vol.4 No.1

본 논문은 듀얼클러치 변속기 변속 메커니즘 개발을 위한 동역학적 시뮬레이션 해석 및 피로수명 해석에 관한 연구이다. 캠을 이용한 쉬프트 포크의 이송으로 기어를 변속하는 개념을 갖는 쉬프트 메커니즘의 작동성 및 설계안 검증을 위해 캠의 회전 속도, 접촉면의 경계조건 및 싱크로나이저 슬리브에서의 저항을 반영한 모델링을 구성하여 동역학적 시뮬레이션을 실시하였다. 각 파트의 응력 및 변형률 발생을 해석하여 설계 개선안을 도출하고, 개선안이 반영된 최종 시작모델의 시뮬레이션 상 최대 응력 발생 시점에서 시프트 포크의 각 접촉면 별 외력 작용을 분석하여 이를 적용한 피로 해석을 진행하였다.