• Title/Summary/Keyword: 얼음의 운동

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Towing Tank Test assuming the Collision between Ice-going Ship and Ice Floe and Measurement of Ice Floe's Motion using Machine Vision Inspection (내빙선과 유빙의 충돌을 가정한 예인수조실험 및 머신비전검사를 이용한 유빙의 운동 계측)

  • Kim, Hyo-Il;Jun, Seung-Hwan
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.10a
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    • pp.33-34
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    • 2015
  • The voyage and cargo volume passing through the Arctic route (NSR) have been gradually increased. The ship-ice collision is one of the most biggest factors threatening the safety navigation of ice-going ships. A lot of researchers are trying to reveal the ship-ice collision mechanism. In this study, some tests that a model ship is forced to collide with disk-shaped synthetic ice are carried out in a towing tank. Then, ice floe's motion (velocity and trajectory) is measured by machine vision inspection.

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빙상경기장의 공조설비

  • 심재곤
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.30 no.5
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    • pp.30-36
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    • 2001
  • 건축, 설비, 생산 등의 공학기술의 진보, 경제력의 성장, 관람 스포츠의 대중화, 생활기반의 여유 등으로 실내체육관의 보급이 증가하고 있으며 빙상 경기장도 이와 같은 추세에 따라 건립이 증가하고 있다. 빙상 경기장은 얼음이 기본조건으로 대부분 천연 또는 인공얼음을 사용하지만 특수한 플라스틱 판을 얼음 대신 이용하는 경우도 있다. 빙상경기를 기사조건이나 계절에 관계없이 4계절 운동으로 할 수 있는 실내 빙상경기장의 종류, 구조, 냉각관 재질 및 설계 시 유의사항 등을 기술하고자 한다.

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Development of a curling pad performance test system to support Korea curling team (국가대표 컬링 대표팀 지원을 위한 컬링 패드 성능 시험 시스템 개발)

  • Kim, Taewhan;Lee, Sangcheol;Kil, Sekee
    • Journal of the Korea Convergence Society
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    • v.11 no.10
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    • pp.25-30
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    • 2020
  • In this study, a test system which can test performance of curling pad was developed to support Korea curling team. The developed system consists of a water tank, a mechanical pad driving system that can perform sweeping movement using a curling pad on surface of ice made by the water tank, and temperature sensors monitoring ice and air temperatures. To control the temperature of ice and humidity/temperature of air around the ice, all system are installed in a chamber that can isolate the developed system from external environment. Eight kinds of curling pads were tested using the developed system. Test result showed that each curling pad revealed different rate of ice temperature increasing. The pad with the highest rate of ice temperature rising was found to be the same as the most preferred pad by the athletes. Therefore, it was confirmed that the method of measuring change of ice temperature by the sweeping performed in this study is an effective method to test the performance of the pad.

인터뷰: 고정일 동서문화사 대표 -"전쟁은 무슨 일이 있어도 절대 안돼" 출판과 인쇄는 문화운동의 중심지

  • Im, Nam-Suk
    • 프린팅코리아
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    • v.10 no.6
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    • pp.92-95
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    • 2011
  • 오는 6월 25일은 한국전쟁이 발발한지 61년이 되는 날이다. 6.25를 겪은 세대이자 '불과 얼음'이라는 6.25전쟁을 소재로 한 소설을 발표한 고산 고정일 동서문화사 대표를 만났다. 고정일 대표는 나이 16세에 출판사를 창업하여 55년을 한결같이 책만들기에만 힘써왔다. 오늘도 다른 사람의 책을 만들고 있으며, 이와 함께 자신의 소설과 동화를 지으며 하루하루를 살아가고 있다.

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A poroelastic model for ultrasonic wave attenuation in partially frozen brines (부분 동결된 소금물에서의 초음파감쇠에 대한 다공성탄성 모델)

  • Matsushima, Jun;Nibe, Takao;Suzuki, Makoto;Kato, Yoshibumi;Rokugawa, Shuichi
    • Geophysics and Geophysical Exploration
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    • v.14 no.1
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    • pp.105-115
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    • 2011
  • Although there are many possible mechanisms for the intrinsic seismic attenuation in composite materials that include fluids, relative motion between solids and fluids during seismic wave propagation is one of the most important attenuation mechanisms. In our previous study, we conducted ultrasonic wave transmission measurements on an ice-brine coexisting system to examine the influence on ultrasonic waves of the unfrozen brine in the pore microstructure of ice. In order to elucidate the physical mechanism responsible for ultrasonic wave attenuation in the frequency range of 350.600 kHz, measured at different temperatures in partially frozen brines, we employed a poroelastic model based on the Biot theory to describe the propagation of ultrasonic waves through partially frozen brines. By assuming that the solid phase is ice and the liquid phase is the unfrozen brine, fluid properties measured by a pulsed nuclear magnetic resonance technique were used to calculate porosities at different temperatures. The computed intrinsic attenuation at 500 kHz cannot completely predict the measured attenuation results from the experimental study in an ice-brine coexisting system, which suggests that other attenuation mechanisms such as the squirt-flow mechanism and wave scattering effect should be taken into account.

Epidemiological Investigation on an Outbreak of Enterotoxigenic E. coli among the Baseball Club Students of High School in Ulsan City, 2014 (2014년 울산시 일개 고등학교 야구부원들에서 발생한 장독소생성대장균의 유행에 관한 역학조사)

  • Kang, Young-Eun;Lim, Hyun-Sul;Lee, Kwan;Kim, Byung-Seok
    • Journal of agricultural medicine and community health
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    • v.40 no.2
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    • pp.53-61
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    • 2015
  • Objectives: An outbreak of food poisoning occurred among the baseball club students at a high school in Ulsan city in 2014. An epidemiological investigation was carried out to examine the infection source and the transmission route of pathogen, and to prevent a recurrence. Methods: A questionnaire survey was conducted for 26 male students and 2 food handlers. Rectal swabs were examined in 7 students and the 2 food handlers, and an environmental investigation was performed. A retrospective cohort study was used to evaluate the association between risk factors and disease. Results: The attack rate was 35.7% (10 persons/28 persons) from June 9 to 14, and Enterotoxigenic E. coli ST/LT was isolated from 7 among 28 persons. The study revealed that no food was a significant risk factor for the outbreak. There were no connection between environmental factors and the outbreak. Conclusions: The major risk factors for this outbreak were presumed to be the contaminated ice cube and ice making machines and eating ice cube from the machines. More strict personal and environmental hygiene need to be enforced to prevent such outbreaks.

Cooling Strategy for Improving the Performance of Endurance Sports in Heat (고온 환경에서 지구성 스포츠의 운동수행력 향상을 위한 냉각요법의 전략)

  • Park, Chan-Ho;Kwak, Yi-Sub
    • Journal of Life Science
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    • v.27 no.5
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    • pp.591-599
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    • 2017
  • It is well established that endurance performance is negatively affected by environmental heat stress. Numerous scientific investigations have attempted to improve performance in the heat with pre-cooling and per-cooling for endurance athletes. Some cooling strategies are more logistically challenging than others, and thus are often impractical for use in training or competition. The purpose of this study was to review the literature on the use of cooling interventions in the improvement of performance and recovery from exercise-induced heat stress. We undertook an examination that focused on the effects of pre-cooling and per-cooling on the improvement in endurance performance and the effects of post-exercise cooling on recovery. The benefits for pre-cooling and per-cooling strategies undertaken in the laboratory setting could be employed by athletes who compete in hot environmental conditions to improve performance. Most laboratory studies have shown improvements in endurance performance following pre-cooling and per-cooling, and in recovery following post-cooling. Cooling strategies such as cooling vest, neck cooling collar, menthol and ice slurry are practically relevant to sports field. Cooling interventions that can be applied frequently to reduce thermal strain prior to, during and directly after training appear to be the best effective strategy to improve performance and recovery. Future research is warranted to investigate the effectiveness of practical pre-cooling and per-cooling strategies in competition or field settings.

On hydraulic characteristic analysis of landslide tsunami (산사태 지진해일의 수리특성 분석에 관한 고찰)

  • Seo, Minjang;Lee, Changmin;Lee, Woo-Dong
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.203-203
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    • 2022
  • 일반적으로 지진해일은 지진, 화산에 의한 융기 또는 침강에 따른 급작스러운 해저지각 운동에 의해 발생하며, 이에 따른 수위변동과 유체운동을 일컫는다. 그 밖에 해안/해저 산사태, 운석 낙하, 빙하 붕괴와 같이 암석, 토사, 얼음, 운석이 바다, 호수의 수면과 충돌하여 해일이 발생하기도 한다. 이 산사태 해일의 피해사례는 많지 않지만, 대부분 인명피해를 동반한다. 이에 과거부터 수리모형실험을 통해 산사태로 생성된 해일의 전파과정을 조사하는 연구들이 수행되었다. 최근에는 컴퓨터 성능향상과 다양한 수치모델이 개발됨에 따라 수치해석이 많이 수행되고 있다. 그러나 산사태 해일의 생성을 직접 모의하기 위해서는 유체-구조 상호작용(FSI; fluid-structure interaction)을 고려할 수 있는 전산유체역학(CFD; computational fluid dynamics)해석이 요구되는 관계로 활발한 연구가 진행되지 않고 있다. 본 연구에서는 FSI에 기초하여 충돌모의에 특화된 LS-DYNA를 이용하여 산사태 해일의 생성, 전파 그리고 직립벽(댐)에서의 처오름 및 파압 등을 검토한다. 그리고 낙하물의 형상, 낙하 높이에 따라 생성된 해일이 댐에 미치는 영향을 분석한다. 또한, 이용하는 LS-DYNA 해석의 타당성 및 유효성을 확인하기 위하여 기존 수리모형실험에서 생성된 산사태 지진해일과 비교·검증한다. 수치해석 결과, 동일한 체적의 낙하물에서는 폭이 좁을수록 최대파고가 낙하물에 근접해 생성되었고, 폭이 넓을수록 파장이 길어지는 것을 확인할 수 있었다. 낙하물의 낙하높이가 높을수록 산사태 지진해일의 파고가 크게 생성되었다. 낙하물로부터 600m 지점에서 설치한 댐에서의 산사태 지진해일의 처오름은 파고 및 파장이 클수록 증가하였다. 산사태 지진해일의 파압 역시 처오름에 상응하게 나타났다. 그러므로 호소에서 산사태 해일이 발생한다면, 댐 및 제방의 안정성에 영향을 미칠 수 있을 것으로 판단된다.

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Development of intelligent thermoregulation textile material for sportswear (스포츠 의류용 지능형 체온조절 섬유소재 개발)

  • Oh, Dong-Ki;Jung, Koo;Yang, Gwang-Wung;Rho, Yong-Hwan
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2012.03a
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    • pp.98-98
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    • 2012
  • 최근 국내외에서 첨단 기능성 섬유에 대한 소비자들의 관심이 높아지면서 다양한 분야에서 기능성 소재들이 개발되고 있다. 특히 기능성 스포츠웨어 시장에서는 계절의 경계를 넘어 야외 활동 중에 사용할 수 있는 제품에 대한 요구가 증가되고 있는데, 날씨가 매우 덥고 햇살이 뜨거운 것에서부터, 얼음처럼 차갑고 추운 것까지 가지각색 인 경우가 있을 수 있다. 이러한 변화무쌍한 날씨에 쾌적한 활동을 하기 위해서는 외부 온도변화에 대응하여 몸을 보호하고 자연환경에 맞설 수 있는 의복의 필요성이 부각되고 있다. 본 연구에서 개발하고자 하는 지능형 체온조절 섬유는 정적상태에서는 보온성과 적외선을 방출을 통한 자가 발열기능을 부여하고, 동적상태에서는 태양열 증폭기능과 운동량에 따른 흡습발열의 기능을 통하여 자연환경과 의복환경의 변화에 대응할 수 있는 스포츠웨어 제품이다. 따라서 보온성이 우수한 PP, acrylate 원사 등을 이용하여 복합 방적사 설계 및 생산을 최적화였다. 또한 흡습발열 성능이 향상된 섬유구조체를 설계하여 개발 원사 구성에 따라 보온 발열 기능성 부여 방법을 달리하여 최적의 성능을 이끌어내는 제품을 개발하고자 하였다.

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Anterior Knee Pain Syndrome & Shin Splint (전방 슬관절 동통 증후군 및 경부목)

  • Kim, Yeung-Jin;Chun, Churl-Hong;Lee, Ji-Wan;Choo, Ji-Woong
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.9 no.1
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    • pp.7-15
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    • 2010
  • Anterior knee pain syndrome would best be defined as a painful condition that arises in or around the patellofemoral joint and is insidious in onset and bilateral, with an enigmatic entity with multiple causes. Although its etiology is uncertain, the cause is often considered to be abnormal lower limb biomechanics, pathology of extensor mechanism, disorder of patellofemoral joint, malalignment or lateral tracking of the patella, soft tissue tightness, muscle weakness. The measurement of patellar alignment has come to be accepted as an integral part of the examination of anterior knee pain syndrome. Various measurement techniques exist, both clinical and radiological, and these have been frequently used in the diagnosis and treatment of the condition.?Treatment depends on the underlying cause of anterior knee pain and should be directed to the cause rather than to the results. Most often, this involves non-surgical measures, such as anti-inflammatory medications, quadriceps exercises, and hamstring stretching. Shin splint, or medial tibial stress syndrome refers a syndrome of pain running along the inner distal 2/3 of tibia shaft. Shin splint is a common problem for athletes whose sport involves a repeated, jarring impact to the leg. A major factor determining the efficacy of the treatment is that correct diagnosis be made of the problem. The varied etiology has led to the development of several theories as to the cause, treatment, rehabilitation and prevention of shin splint. The management is rest, ice massages, pain relief by medication, and muscle strengthening exercise. Proper rehabilitation and preventative measures can ensure that there is no further recurrence.

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