• 제목/요약/키워드: Ice management

검색결과 121건 처리시간 0.03초

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

  • Matsushima, Jun;Nibe, Takao;Suzuki, Makoto;Kato, Yoshibumi;Rokugawa, Shuichi
    • 지구물리와물리탐사
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    • 제14권1호
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    • pp.105-115
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    • 2011
  • 유체를 포함하는 혼합 매질에서의 탄성파 고유 감쇠에 대한 다양한 메커니즘 중, 탄성파 전파 시 고체와 유체 사이에서의 상대적 운동은 가장 중요한 감쇠 메커니즘 중의 하나이다. 선행 연구에서는 얼음의 미세 공극 안에 존재하는 소금물이 초음파의 전파에 미치는 영향을 분석하기 위하여 얼음과 소금물이 공존하는 매질에서 초음파 전파 실험하였다. 부분적으로 동결된 소금물에서 각기 다른 온도에서의 초음파 감쇠의 물리적인 메커니즘을 350 ~ 600 kHz의 주파수 대역에서 규명하기 위하여, Biot 이론에 입각한 다공성의 탄생 모델을 도입하여 초음파의 전파를 측정하였다. 고체상은 얼음으로, 액체상은 소금물로 가정한 뒤 펄스 핵자기공명기술로 측정한 유체의 성질을 이용하여 각각의 온도에서의 공극률을 계산한 결과, 실험으로 측정한 감쇠값은 500 kHz에서 계산된 고유 감쇠값과 다르게 나타났으며 이는 squirt -flow 메커니즘과 파의 산란 효과와 같은 다른 감쇠 메커니즘도 고려해야 한다는 것을 의미한다.

선박조종시뮬레이터를 이용한 해적 대응훈련에 대하여

  • 이동섭
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2013년도 추계학술대회
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    • pp.105-106
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    • 2013
  • 2011년 1월 21일 새벽 대한민국 해군 청해부두는 "아던만의 여명"이라는 작전명으로 소말리아 해적에 납치되었던 M/T "삼호주얼리"호를 구출하였으며, 이 작전결과 피납선박 및 선원 21명을 구조하였으며 작전 중 선장이 부상을 입었으며 해적 8명을 사살하고 5명을 생포하는 전과를 올렸다. 한국해양수산연수원은 2011년도 도입한 Full-mission Shiphandling Simulaor(다기능 선박조종시뮬레이터)를 설치하면서 항행, 조종훈련 및 비상, 선교조직훈련 뿐 만 아니라 Offshore훈련과 Dynamic Positioning System Operator훈련, Ice Navigation훈련, 테러방지 훈련(Anti-Terror Training) 및 해적대항 훈련(Anti-Piracy Training) 등 Crisis Management훈련을 할 수 있는 기능을 추가하였으며, 특히, 테러방지 훈련(Anti-Terror Training) 및 해적대항 훈련(Anti-Piracy Training)에 대한 훈련과정을 소개하고자 한다.

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극저온에서 풍속의 영향에 따른 발열기자재의 최적설계 (Optimum Design of the Heating Equipment by Influence of Wind Speed at Cryogenic Temperature)

  • 조현준;윤원영
    • 품질경영학회지
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    • 제48권3호
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    • pp.463-479
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    • 2020
  • Purpose: The purpose of this study is to evaluate the performance of heating equipments by implementing the extreme environment in which ships navigating the ice zone are exposed and to study and apply the experimental method to infer the optimized design for each factors. Methods: It is required to verify by analysis and experiment how the environment with low temperature and wind speed implemented through the test facility affects the heating walk-way and The optimum design of the heating walk-way in that extreme environment is derived using the Taguchi technique. Results: The results of this study are as follows; It was found the effect on the condition of each factor and derive optimized conditions that satisfy the performance condition of the heating walk-way in extreme use environment. Conclusion: Ships operating in Polar waters require reliable and durable facilities for all environments during sailing.

50대 중년 남녀의 칼슘 섭취실태, 인식 및 기호도 조사 연구 (A Study on the Preference for Calcium Source Foods, Recognition and Calcium Intake of a Middle-Aged People)

  • 한재숙;이연정;최영희
    • 한국식품조리과학회지
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    • 제14권1호
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    • pp.33-43
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    • 1998
  • This study was peformed by questionnaire to investigate the recognition, preference and intake of calcium and related food behaviors of middle-aged people (males 600, females 550) in Daegu area. The daily intake was determined by 24-hr dietary recall method. The results were summarized as follows: The meal skipping, diet and nutrition consideration ratio of the subjects were 40.6, 11.1, 34.6% respectively. The recognition scores of calcium of the subjects were 14.3 for male and 15.1 for female, respectively. Also the preference scores of calcium source foods of the subjects were 3.6 for male and 3.5 for female. They preferred laver, cabbage, bean curd and lettuce, in that order, but they disliked cheese and ice cream. The variety of calcium source foods was remarkably low. Milk products were the lowest preferred and eaten calcium source foods. A day's calcium intake was 68.4% (478.6 mg) of the RDA for Koreans. There were significant positive correlations among the recognition, preference and intake scores of calcium.

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솔잎분말을 첨가한 소시지의 품질특성 (Quality Characteristics of Sausage with Added Pine Needle Powder)

  • 권순용;신명은;이경희
    • 동아시아식생활학회지
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    • 제22권3호
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    • pp.357-364
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    • 2012
  • Quality characteristics of sausage with added pine needle powder (0%, 0.5%, 1.0%, 1.5%, 2.0%, and 2.5%) as an ingredient. The basic ingredients of sausage consisted of pork meat 60%, olive oil 20%, and ice water 20%. Sensory properties of sausage were analyzed by a sensory test, and the texture and color characteristics were measured using a texturometer and color meter, respectively. In the results of the sensory test, taste, texture, and overall preference were highest in the sample with added 1.5% pine needle powder. The sausage with added 1.5% pine needle powder was moderate in color intensity, pine needle flavor, and astringent taste. Hardness and gumminess of sausage were higher in 1.0% and 1.5% pine needle powder. However, springness and chewiness of sausage showed no significant differences. In terms of color intensity of sausage, L-value and a-value were lower and b-value was higher, depending on the pine needle powder amount. Development of off-flavor of sausage during storage was greater in 0% and 1.5% added sausages than in 2.0% sausage with increasing storage time. As a conclusion, sausages with added 1.5% and 2.0% pine needle powder were the most suitable for making functional sausage with added pine needle powder.

Parametric investigation of a hybrid vehicle's achievable fuel economy with optimization based energy management strategy

  • Amini, Ali;Baslamisli, S. Caglar;Ince, Bayramcan;Koprubasi, Kerem;Solmaz, Selim
    • Advances in Automotive Engineering
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    • 제1권1호
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    • pp.105-121
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    • 2018
  • The hybrid electric powertrain is a robust solution that allows for major improvements in both fuel economy and emission reduction. In the present study, a through-the-road hybrid vehicle model with an electric motor driving the rear axle and an Internal Combustion Engine (ICE) driving the front axle has been constructed. We then present a systematic method for the determination of a real time applicable optimal Energy Management Strategy (EMS) for a hybrid road vehicle. More precisely, we compare the performance of rule-based EMS strategies to an optimization-based strategy, namely ECMS (Equivalent Consumption Minimization Strategy). The comparison is conducted in parallel with a parameterization of the size of the internal combustion engine and the implementation of a Continuously Variable Transmission (CVT) that allows following the line of best fuel economy. For the FTP-75 driving cycle, the constrained engine On-off control algorithm is shown to offer a 28% improvement potential of fuel consumption compared to the conventional internal combustion engine while the ECMS strategy achieves an improved potential of nearly 33%.

급식교와 비급식교 아동의 식생활습관에 관한 비교 연구 (A Comparative Study on Dietary Habits of Children in Elementary School by School Lunch Program)

  • 박경복;김정숙;한재숙;허성미;서봉순
    • 한국식생활문화학회지
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    • 제11권1호
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    • pp.23-35
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    • 1996
  • The main purpose of this study was to observe the effect of school lunch program on dietary habits of elementary school children and their food preferences. A questionnaire survey was conducted on 785 children and their mother in ele-mentary school with and without school lunch program. The results of this study can be summarized as follows: 1. 91.1% of subjects were eating rice for breakfast menu and 12.2% of subjects were skipping breakfast every morning. 2. Most of the children preferred fruits, ddugboggi, ice cream, fritter, cookie, bread, beverage and hot dog for snacks. 3. Despite of its restrictive practice, the school lunch program proved to be contributory to the improvement of children's food intake habits, table manners, keeping social order, sanitary consiousness, gratitude for their parents. 4. Children preferred kimbap, bokumbap and hamburger for main dish, fish jelly soup, brown seaweed soup and bean-sprout soup for soup, animal food for side dish and frying saute for cooking methods. 5. Most of the children disliked crown daisy, green pepper, mushroom, green onion, onion, dropwort, soybean and carrot for their food materials.

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국가대표 좌식배구 선수들의 운동상해 조사연구 (A Study on Sports Injuries in Korean National Sitting Volleyball Players )

  • 이창렬
    • 대한물리의학회지
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    • 제19권2호
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    • pp.107-122
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    • 2024
  • PURPOSE: This study examined sports injuries among national sitting volleyball players and to provide baseline data for the development of programs to prevent injuries and enhance performance. METHODS: The study surveyed 21 national team athletes (12 males and nine females) participating in the 4th Hangzhou Asian Para Games. The questionnaire consisted of 17 items, including general information, type of disability, sites and types of sports injuries and their causes, the current state of sports injuries and the treatment and management of injuries. RESULTS: The survey results suggested that the most common injury sites were the finger, shoulder, and waist. The most frequent types of injuries were sprain, muscle cramp, and LBP. The causes were insufficient warm-up, playing unhealed and carelessness. Injuries were most prevalent during morning training and in the winter. Most injuries occurred in practice, and the actions most likely to cause injuries were blocking, spike and sitting movements. Ice and spray were the most common treatments, usually administered by the athletes themselves. Physical therapy was the most common post-injury management, and the most common sequelae involved continuing to use despite pain. CONCLUSION: Based on these results, systematic and individualized training and therapeutic support tailored to the characteristics of sitting volleyball and the types of disabilities are necessary to prevent and manage sports injuries among national players. Continuous injury management by medical staff, particularly physical therapists, is essential to maintain the health of disabled athletes.

수도권 일부지역 외식업체의 위생 관리 현황 및 실태조사 (The Status and the Actual Sanitation Management Conditions of Food Services within the Metropolitan Area)

  • 우인애;황윤경;이윤신
    • 한국식품영양학회지
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    • 제21권3호
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    • pp.355-365
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    • 2008
  • The purpose of this study was to investigate the food sanitation awareness and performance of foodservice industry employees. Based on a literature review, a questionnaire was developed to identify the food sanitation education, experience, knowledge, and food sanitation practices of the employees. A total of 376 Korean food industry employees participated, and there were 344 usable questionnaires. In the analysis of food sanitation knowledge, the statements "clip fingernails short and do not use nail polish", and "if feeling sick, even with a minor cold, speak to your supervisor immediately", had the highest and lowest percentages of correct answers, respectively. In assessing employee sanitary management practices, many correctly acknowledged "clip fingernails short and do not use nail polish" and "wash hands after using the toilet", which received high scores; however, "use hands to pick up ice" and "if feeling sick, even with a minor cold, speak to your supervisor immediately" had low scores. The sanitary knowledge and practice levels of the employees were not significantly different according to gender, age, work area, job title, or duration of duty. Among the surveyed industries, employees of special restaurants had the least sanitary knowledge(p<0.05) and practice scores(p<0.001). Employees who had worked for $1{\sim}3$ years presented the least sanitary management practice level scores(p<0.05).). In addition, college students and participants without hygiene educational experience showed the least levels of sanitary knowledge(p<0.01). Scores for sanitary management practice were higher when hygiene education was regularly conducted more than once per month. Employees showed significantly higher knowledge and sanitary management practice levels when they were required to use a sanitary checklist(p<0.001), and employees who were trained in HACCP had significantly higher sanitary checklist scores(p<0.05). In foodservices that applied HACCP, the employees showed higher knowledge and sanitary management practice levels(p<0.001).

SVM(Support Vector Machine) 기법을 활용한 노면상태 판별 알고리즘 개발 (A Development of The Road Surface Decision Algorithm Using SVM(Support Vector Machine) Clustering Methods)

  • 김종훈;원제무
    • 한국ITS학회 논문지
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    • 제12권5호
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    • pp.1-12
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    • 2013
  • 도로의 결빙, 적설, 젖음 등 기상상황 및 표면 상태에 의한 안전사고 발생은 지속적으로 발생하고 있는 상황이다. 이는 운전자 본인의 부주의 및 안전 운전의식 부족 등 개인의 역량에 기인하는 부문도 있지만, 도로관리 주체(정부 및 공공 등)의 도로 상태 정보제공 미흡으로 인한 경우도 있어 이와 관련된 연구의 필요성이 대두되고 있는 추세이다. 본 연구는 카메라(Stereo camera)의 영상 정보를 수집하여, 편광계수 및 웨이블릿 변환(Wavelet transform) 등을 통해 기존의 단일 차원 분류알고리즘과 달리 다차원 분석이 가능한 SVM 분류기법을 활용하여 노면상태 판별 알고리즘을 개발하였으며, 실제 도로상에서 4개의 상태(마른노면, 젖은노면, 적설노면, 결빙노면)에 대한 검지 인식 성공률을 실험 및 분석하였다.