• 수산해양기술연구
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• 제49권3호
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• pp.270-281
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• 2013

Hydro-acoustic surveys with scientific echo sounder were carried out to estimate the total density and distribution of the juvenile cod in Jinhae bay, Korea. The surveys were conducted 4 times from May to June using 2 frequency method (38kHz and 120kHz) and beam trawl were used to investigate the species composition. Also the catch amounts of juvenile cod were compared with the cod density estimated by the hydro-acoustic method. It was confirmed that the juvenile cod was stayed in Jinhae bay in early June and There was the relationship between catch of juvenile cod and the estimated density by hydro-acoustic survey. The number of juvenile cod was consequently about 365,000 fish (CV 12.9%) in May and 113,000 fish (CV 9.2%) in May based on the hydro-acoustic data.

• 한국해양공학회지
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• 제23권1호
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• pp.89-95
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• 2009

The purpose of the present study was to evaluate the safety under extreme environmental conditions and the dynamic safety under service environment conditions, of oceanographic buoy mooring systems consisting of a variety of materials, including chain, wire rope, nylon rope, and polypropylene rope. For the static safety assessment of a mooring system, after the calculation of external forces and the division of a mooring system into finite elements, the numerical integral was conducted to yield the elemental static tension until satisfying the geometrical convergence condition. To evaluate the dynamic safety, various processes were considered, including data collection about the anticipated areas for mooring, a determination of the parameters for the interpretation, the interpretation of the dynamic characteristics based on an analytic equation that takes into account the heave motion effect of a buoy hull and a mooring system, and a fatigue analysis of the linear cumulative damage. Based on the analysis results, a supplementary proposal for a wire rope that has a fracture in an actual mooring area was established.

• Journal of Advanced Marine Engineering and Technology
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• 제34권8호
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• pp.1222-1229
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• 2010

비선형 측심기를 이용한 초고해상 음향탐사는 기존의 고해상 음향탐사보다 투과력은 작지만 해상력이 뛰어나기 때문에 천해역에서의 해저환경조사에 유용하게 사용된다. 비선형 지층탐사 시스템은 정확한 수심측정 뿐 아니라 퇴적층과 하부구조에 대한 상세한 정보를 제공한다. 특히 상부 퇴적층의 정밀층후 및 퇴적구조 확인을 통해 해저에 파묻혀 있는 pipeline, 침몰선박, 인위적 물체 등에 대한 탐색에 이용된다. 이 연구에서는 초고해상 지층탐사기를 이용하여 얻어진 지층탐사 기록과 지질자료를 대비하여 오염퇴적층을 구분하였다. 그리고 지층 기록에 나타나는 음향이상을 해석하여 해저에 매설된 케이블의 매설 깊이를 검측하였다.

• 한국기계가공학회지
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• 제19권7호
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• pp.89-97
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• 2020

Container vessels continue to grow in size, led by global shipowner. Large ships can be loaded more cargo at a time, reducing the cost of transportation per teu. this eventually leads to economies of sale, in which the production cost per unit decreases with increasing output. in accordance with the 70th Convention of the Marine Environment Protection Committee of the International Maritime Organization, as of January 1, 2020, MARPOL Annex VI Regulation 14.1.3 will be effective. All vessels must be meet these criteria to reduce Sox emissions and reduce NOx emissions by reducing the content of manned sulfur oxides from 3.5% to less than 0.5%, otherwise IACS Member States Entry to the port is denied. in order to do that need to LNG storage tank. in this study characteristic of the material after line heating (600℃,700℃,800℃,900℃) of 9% Ni steel used in the manufacture of LNG fuel tank of ship were verified using by mechanical test. In the heating method by line heating. The initial properties of steel are changed by variables such as temperature, time, speed. The experimental data of line heating presented in this paper confirmed that the initial change of 9% Ni steel could be minimized.

• 여성건강간호학회지
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• 제1권1호
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• pp.28-43
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• 1995

The relationship between perceived social support and adaptation to maternal role for first-time mothers was investigated in this descriptive correlational study. A nonprobable sample of 90 first-time mothers were selected, who had uncomplicated perinatal experiences and delivered healthy and term newborns as well. The data was collected during a home interview at 4-6weeks postpartum. The outcome of adaptations was defined as the level of sensitivity in parent-infant interactions and of the self confidence in infant care. The perception of social support in the primiparous was assessed by the NSSQ during the postpartum. The results obtained from this study are summarized as follows : 1. The mean score of the perceived total functional support was $116.6{\pm}37.5$ points (affective : 38.1 affirmative : 39.3, aid : 39.3), and the score of the total network support was $45.2{\pm}13.9$ points (size : 4.9, duration :19.8 frequency : 20.4). These scores tended to be slightly low. 2. The mean score of the self confidence on the infant care activity as the subjective aspect of the maternal role adaptation (MRA) was 56.5 points (86.9%), whereas that of the sensitivity of the mother-infant interaction of the MRA was 78.9 points (63.2%). 3. The subjective aspect of the MRA has showed a positive relation ship with the aid dimension of the functional support. And the objective aspect of the MRA also showed a positive relationship with the total functional support and the total network support. However the correlating degrees were slightly low. In conclusion, the primiparous mothers perceived that they had received a small amount of social support during the postpartum period, suggesting the need of various kinds of social support to promote the MRA for the primiparous.

• 한국수산과학회지
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• 제3권2호
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• pp.117-119
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• 1970

1967년 11월부터 1968년 12월까지 사이에 부산부근의 낙동강 유역인 선암, 가락, 성산, 하단에서 채집된 체장 7cm부터 33cm까지 사이의 풀망둑 Synechogobius hasta (TEMMINCK et SCHLEGEL) 1,050개체를 재료로 체장$\cdot$체중의 상관 관계를 조사하였다. 1) 전 개체에서 체장의 신장에 따른 체중의 회귀를 식으로 표시하면 $Y=0.09863X^{2.17926}$이였다. 2) 체장 20.5cm부터 27.5cm까지 사이에서는 성숙자 산란의 영향으로 정상적인 상대 성장을 보이지 않는다 (Fig. 1). 3) 체장 7.5cm부터 19.5cm까지의 상대 성장은 $Y=0.04995X^{2.472l6}$, 체장 28.5cm부터 32.5cm까지의 상대 성장은 $Y=0.0004127X^{3.67265}$으로 표시되었다.

• 한국수산과학회지
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• 제35권6호
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• pp.563-567
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• 2002

Developing base data on luring fish schools into netting position by the use of underwater audible sound on japanese parrot fish Oplegnathus fasciatus found in the coastal waters of Jeju Island, S. Korea. Auditory threshold was determined by the heartbeat condition technique using pure tones coupled with a delayed electric shock. The audible range of japanese parrot fish extended from 80 Hz to 500 Hz with a peak sensitivity at 200 Hz. The mean auditory thresholds at the frequencies of 80 Hz, 100 Hz, 200 Hz,300 Hz and 500 Hz were 104 dB, 95 dB, 91 dB, 99 dB and 113 dB, respectively. As the frequency became higher than 200 Hz, the auditory threshold increased almost linearly with increasing frequency. Critical ratios of fishes measured in the presence of masking noise in the spectrum level range of 69$\~$78 dB (0 dB re 1$\mu$Pa/$\sqrt{Hz}$) ranged from 21 dB to 40 dB at test frequencies. The noise spectrum level at the start of masking was about 70 dB within the test frequency range. The sound pressure level of 100$\~$200 Hz recognized by japanese parrot fish under the ambient noise is above 91 dB and the critical ratio for them is above 21 dB.

• 한국항해항만학회지
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• 제33권8호
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• pp.531-537
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• 2009

항만국 통제 점검(Port State Control Inspection)은 해양 선박사고의 대부분이 선박 자체의 결함 보다는 인적 과실에 의하여 발생되고 있다는 사실을 인지하고 선박을 운항하고 있는 선원의 자격 검증과 교육훈련 부문의 점검을 강화하고 있다. 이에 따라 날로 강화되고 있는 국제 협약과 국제 법규를 충족시키기 위한 선원의 재교육훈련을 어떻게 효과적이고 효율적으로 시행하느냐가 해운기업에 있어서 풀어나가야 할 숙제라 할 수 있다. 이에 본 연구에서는 국내 S사의 피 교육자들을 대상으로 설문조사를 실시하고 연령, 학력, 근무연수, 직위 등을 기준으로 응답자를 분류하여 교육 훈련의 목적 및 필요성, 자기 동기부여, 교육효과 및 성과, 교육훈련의 만족도 등 4개 항목에 대한 인식의 차이를 분석하고 교육의 효과를 높일 수 있는 교육 방안 수립을 위한 시사점을 도출하였다.

• 한국항해항만학회지
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• 제38권6호
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• pp.585-591
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• 2014

본 논문의 주 목적은 프루드 수가 0.5 이상인 중형 경비정의 속도성능을 모형시험 이전에 CFD 결과를 바탕으로 기존의 모형시험자료를 활용하였다. 모형시험 이전에 CFD를 이용하여 선속 별로 추정된 제동마력이 주어진 엔진마력을 만족하는지를 평가 하였다. 대상선박은 선미가 서로 다른 두 가지 선형을 선정하였다. 점성 유동장 계산은 상용 CFD 코드인 STAR-CCM+를 사용하였으며, 자유수면과 자세 변화(동적 트림)를 모두 고려하였다. 알몸 선체의 저항 값은 CFD를 이용하여 추정되었다. 점성 유동 해석을 통해 두 가지 선형의 자유수면 파형, 압력분포, 한계유선 그리고 프로펠러 면에서의 속도분포를 비교하였다. 점성 유동 해석 결과를 바탕으로 두 가지 선형에 대한 유효마력 즉, 저항성능을 평가하였다. 부가물 부착에 따른 저항 증가량과 준추진효율 계수(ETAD, ${\eta}_D$)는 모형시험 자료를 활용하였다. 중형 경비정과 같은 고속선박에 관한 속도성능 추정법이 CFD와 기존 시험자료를 이용하여 개발되었다.

• 재활간호학회지
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• 제2권1호
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• pp.85-94
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• 1999

The purposes of this study were to identify sexual interest and adjustment in patients with spinal cord injury and to determine the factors that relate to sexual adjustment. A total of 134 persons in this study was the members of spinal cord injury organization and the impatients in rehabilitation unit between February and June 1999. Five questionnaires were answered concerning importance of life events, sexual concern, sexual adjustment, relationship with a sex partner, and depression. The collected data were analyzed by Frequency, t-test, ANOVA and pearson correlation. The results were as follows : 1) Considering the importance among 11 areas of life, economic status occupied the top, sex life held the sixth rank, and the mean rating for social life being 3.78 was the lowest of all. 2) As regard to 7 topics related to sexuality, the most attention was drawn to methods and techniques achieving sexual satisfaction, and the next interest was for helping partners cope emotionally with sexual dysfunction. 3) The mean for sexual adjustment and depression was average, and the mean for sex partner relationship was high. 4) Sexual adjustment in spinal cord injury patients correlated with economic status and sex partner relationship. While It was inversely correlated with age and depression. It was found that lower age and less depression play a positive role on sexual adjustment by SCI people. Also, higher economic status and favorable sex partner relationship increase sexual adjustment. In conclusion, a sex partner relationship, depression, economic status, and age seemed to influence on their sexual adjustment after SCI. Also, psychosocial factors would be more important for satisfying sexual life and relation ship rather than physical factors.