• 한국항공우주학회지
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• 제38권1호
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• pp.22-28
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• 2010

복합재 구조물의 손상을 탐지하기위해 비파괴 검사법이 폭넓게 사용되고 있다. 태핑시험은 복합적층판의 손상을 탐지하는데 가장 일반적으로 사용하는 방법이다. 이 방법은 가벼운 해머 같은 장치를 이용하여 검사부위를 두드리고, 국부적인 강성변화를 이용하여 구조물의 손상을 평가한다. 진동신호의 변화는 동적인 접촉하중을 측정하여 탐지할 수 있다. 본 연구에서는 구조물에 층간분리나 표면균열 등의 손상이 존재하는 경우 태핑 시 충격하중이력의 특성이 변하는 것을 보였다. 그리고 손상의 영향을 검토하기위해 균열이 있는 복합재 로터블레이드에 대한 충격해석을 수행하였다.

• The Journal of Asian Finance, Economics and Business
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• 제7권10호
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• pp.751-759
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• 2020

This study examines the impact of mergers on the financial performance of the Jordanian public shareholding companies. The study employs data collected for a sample of 10 Jordanian non-financial public firms that were engaged in legal horizontal merger deals between 2000 and 2013. The data was collected from the published annual financial reports of the merging companies and comparative companies for three years before the merger and three years after the merger. Event study methodology was applied to examine the data. Four measures of financial performance (FP) were used, which are return on assets (ROA), return on equity (ROE), earnings per share (EPS), and net profit margin (NPM). Two methods were used in the analysis - the change model and the intercept model using financial performance raw data and industry-adjusted data. The findings in general showed no significant impact of mergers on the financial performance of merging firms using the change model. However, by using the intercept model, significant impact of mergers on the financial performance was found on the sample of the study. The significant impact was found for mergers on the raw ROE of the merging firms, and on the ROA and NPM of the industry-adjusted firms.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2016년도 학술발표회
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• pp.204-204
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• 2016

Thailand had set the National Water Management Strategy which covered main six areas in the next 12 years, i.e., by priority: (1) water for household, (2) water for agricultural and industrial production, (3) water for flood and drought management, (4) water for quality issue, (5) water from forest conservation and soil erosion protection, (6) water resources management. However due to the climate change impact, there is a question for all strategies is whether to complete this mission under future climate change. If the impact affects our target, we have to clarify how to mitigate or to adapt with it. Vulnerability assessment was conducted under the framework of ADB's (with the parameters of exposure, sensitivity and adaptive capacity) and the assessments were classified into groups due to their different characteristic and the framework of the National Water Management Strategy, i.e., water supply (rural and urban), water for development (agriculture and others), water disasters (floods (flash, overflow), drought, water quality). The assessments identified the parameters concerned and weight factors used for each groups via expert group discussions and by using GIS mapping technology, the vulnerability maps were produced. The maps were verified with present water situation data (floods, drought, water quality). From the analysis result of this water resources management strategy, we found that 30% of all projects face the big impacts, 40% with low impact, and 30% for no impact. It is clear that water-related agencies have to carefully take care approximately 70% of future projects to meet water resources management strategy. It is recommended that additional issues should be addressed to mitigate the impact from climate risk on water resource management of the country, i.e., water resources management under new risk based on development scenarios, relationship with area-based problems, priority definition by viewpoints of risk, vulnerability (impact and occurrence probability in past and future), water management system in emergency case and water reserve system, use of information, knowledge and technology in management, network cooperation and exchange of experiences, knowledge, technique for sustainable development with mitigation and adaptation, education and communication systems in risk, new impact, and emergency-reserve system. These issues will be described and discussed.

• 한국운동역학회지
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• 제20권1호
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• pp.25-32
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• 2010

This study was performed to investigate the kinematic factors on the head hitting motion based on weight change of bamboo swords in kumdo. The kinematic factors, needed time per phase, COB displacement and velocity, angle(wrist, elbow, shoulder joint, hip joint, knee joint), were analyzed by the 3-D motion analysis method against 6 male middle school athletes. The results were as follows. 1. The needed time of head hitting motion based on weight change of bamboo swords was shorter when weight was heavier. 2. The COB displacement of left/right was bigger when weight was heavier. the displacement of right foot was higher at backswing phase and impact phase when weight was heavier and at impact time when weight was lighter. 3. The COB velocity was faster at impact time when weight was heavier, the velocity of sword tip was fastest for each event with bamboo sword weight of 440 g. 4. The angle of left elbow was smaller at top of backswing and impact when weight was heavier, the angle of left shoulder was bigger when weight was heavier, the right knee angle was biger at start when weight was heavier, at impact when weight was lighter.

• 대한기계학회논문집A
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• 제31권7호
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• pp.764-776
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• 2007

On the human-rifle system, the human body is affected by the firing impact. The firing impact will reduce the firing accuracy and change the initial shooting posture. Therefore the study of biomechanical characteristics using human-rifle modeling and numerical investigation is needed. The musculoskeletal model is developed by finite element method using beam and spar elements. In this study structural analysis has been performed in order to investigate the human body impact by firing of 5.56mm small caliber machine gun. The firing experiments with the standing shooting postures were performed to verify analytical results. The result if this study shows analytical displacements of the human-rifle system and experimental displacements of the real firing. As the results, the analytical displacement and stress of human body are presented.

• 패션비즈니스
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• 제21권4호
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• pp.61-72
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• 2017

The purpose of this study was to analyze the impact of climate change cognition on clothing behavior of fashion consumers to understand the impact of climate change on the fashion system. An online survey was conducted of 385 people in their 20s-50s working in the fashion industry as well as general consumers. Data collected from surveys were analyzed by factor analysis and t-test. Results are as follow: First, climate change cognition consists of four sub-dimensions, which are 'knowledge of climate change' and 'recognition of climate change in Korea'. Second, clothing behavior related with climate change consists of six sub-dimensions, which are 'environmentally-friendly fashion purchases', 'new clothes-wearing style affected by climate change', 'ethical fashion consumption', 'pursuit of functional fashion', 'pursuit of seasonless fashion', and 'clothes-wearing in response to climate change.' Last, the group with higher cognition of climate change than the group with lesser cognition had significantly higher degree of trying new styles created because of climate change, making ethical fashion purchases, pursuing functional fashion, and wearing clothes in response to climate change.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.262-264
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• 2002

This paper describes the proposed application of MLF(marginal loss factor) in korean wholesale electricity market in accordance with the proposal of wholesale market design, and presents the analysis result of the impact of MLF change on the electric power trading when the reference node for the MLF calculation is changed.

• 환경영향평가
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• 제25권4호
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• pp.296-306
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• 2016

기후변화에 대한 영향 및 위험은 지역적, 국지적 차원에서 더욱 확장되므로 기후변화에 따른 지역적 영향 및 특성을 반영한 기후변화 적응대책 마련의 필요성이 커지고 있다. 이에 본 연구에서는 기초지자체 적응대책의 분야별 사업 수 및 예산의 특성을 분석하고 피해사례와 비교 검토하여 기후변화 적응대책의 개선방향을 제시하고자 했다. 기초지자체 적응대책 특성 분석을 위해 군집분석을 통하여 지자체 적응대책의 유형별 특성을 파악 했다. 적응대책의 계획이 실제 기후변화로 인한 피해 내용을 잘 반영하고 있는지 검토하기 위하여 과거 24년 동안 지자체별 관측 영향 결과(신문기사 2,565건)와 비교 분석을 수행했다. 군집분석 수행 결과 군집은 4가지 유형으로 구분되었다. 전국 피해 유형으로 재난재해, 건강 부분에서 공통적으로 피해 빈도가 높은 것으로 분석되었으며, 적응계획 또한 재난재해, 건강, 농업, 물 관리 순서로 높은 비율을 보였다. 하지만 피해 사례 반영의 비중과 단기 및 장기 미래에 대한 고려 수준에 따라서 각 군집별로 피해빈도와 적응계획의 특성에서 차이를 보였다. 본 연구의 결과는 향후 기초지자체 특성 및 지역별 실질적 피해에 기반 한 적응대책 마련의 기초자료로 활용될 수 있을 것이라고 판단된다.

• 한국운동역학회지
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• 제17권1호
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• pp.29-39
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• 2007

This study were obtained elapsed time phase-by-phases, displacement, user angle, velocity and angular velocity to analyse kinematically contributing factors at impact of forehand drive motion, on targeting three male players. The results of the study were presented as follows; In the forehand drive swing, the elapsed time by phases was a total of .52 seconds: .30 seconds from backswing to impact and .22 seconds from impact to follow-through, Considering the mean change in locations of COM of each(part$\rightarrow$body segment) at impact, racket head, left shoulder, right wrist and left hip, the left-right directions(X-axis) were showm to be each $.61{\pm}.03$, $1.19{\pm}.08$, $.66{\pm}.03$, $.94{\pm}.06$, and $.45{\pm}.03m$. The displacement differences of COM of each body segment were shown to be -.57, -.05, -.33, and .16m. For the vertical direction(Z-axis), the center of mass was lowest at impact and highest at E3. For the displacement of the right wrist on the left hip, the right wrist moved to .82m to the lower direction without change in the locations of the hip from E1 from E2. When the left hip moved .02m from E2 to E3, the right wrist moved .7m in the upper direction. In respect to the velocity of each body segment, the hip and the shoulder joint accelerated and then the wrist followed. Then the right wrists of all the subjects and their racket heads showed maximum speed, and an effective swing was observed. At the angle of each part, the angle of the right wrist was the smallest at the backswing and the largest at the moment of the impact. Then it increased gradually in the follow-through section. In respect of angular velocity for subject A, the hip moved and the largest change occurred. Immediately before the impact, the subject made a swing using his right wrist, his hip, and the shoulder joint, showing the maximum value, which was judged to be effective.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 추계학술대회 논문요약집
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• pp.16-16
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• 2003

In this study, for a safety assessment of wheelchair occupant in side impact, we used a dynamic sled impact test results. The test was carried out total 6 times and impact speed was 13g$\pm$0.43/28km/h$\pm$0.95, By using EURO SID-1 dummy, head performance criteria(HPC), abdominal peak force, etc. were measured. We evaluated wheelchair occupant safety by motion criteria(MC) which was measured by head, trunk and side deformation change of wheelchair and Head & Neck injury criteria(HNI) measured by using head and neck deformation angle and time relation. When we assumed that the maximum injury value in side impact was 100%, the results of motion criteria(MC) of wheelchair occupant were max 80.3, mim 32.3 and average 60.3%, Head & Neck injury criteria(HNI) value were max 118.4, min 14.5 and average 59.7%.