• Ocean and Polar Research
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• 제23권2호
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• pp.63-75
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• 2001

Species composition and community structure of the fouling found on the hulls of 28 ships traveling through 6 main shipping routes (SR)in the Far East Sea Basin were analyzed using statistical methods. Samples obtained during 1976-1990 expeditions of the Institute of Marine Biology were used for the analyses. These samples were taken from the ships anchored in the harbor by SCUBA diving and in dry-docks of the Vladivostok ship-repairing yard. Similar composition of the fouling communities occurred on the ships travelling the same SR. In five cases, fouling was dominated by different Cirripedia communities. And, in one case, a community of the mussel Mytilus trossulus was found. In most cases the results of the factor analyses showed extremely low level of the relationships among different animals and algal species in fouling communities. Each ocean-going ship had an original structure of the fouling. Spatially disconnected animal associations of tropical and boreal origin may simultaneously coexist at the same ship. This paper testified to the originality of the zone of anthropogenic substrata as a benthos concentrator in the pelagic regions of the world ocean. The fouling from different zones showed that each zone possesses peculiar features and regularities of the composition and relationships between organisms dwelling here.

• 한국응급구조학회지
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• 제18권2호
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• pp.45-58
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• 2014

Purpose: This study aimed to investigate the level of knowledge and education regarding basic life support (BLS) among scuba divers. Methods: Data collected from 125 scuba divers in Jeju-do were subjected to frequency, t-test, ANOVA, and Chi-square analyses using the SPSS 18.0 program. Results: 42.1% of the subjects was trained BLS for more than an hour less than 4 hours, and 52.6% of the subjects was trained BLS for less than 3 months in scuba diving institutions. Statistically significant difference was observed in the competence for performing cardiopulmonary resuscitation during BLS education according to gender and age further regarding the necessity of BLS education, significant difference was observed with respect to age, job, academic background, monthly income, and participation period of scuba divers. The divers wished to learn cardiopulmonary resuscitation (72.8%), medical first aid (8.0%), and measures to be taken in cases of trauma (8.0%). The knowledge score for BLS among scuba divers was significantly different depending on the gender, age, marital status and frequency of participation. Conclusion: It is necessary to develop and implement a safety education program for scuba divers.

• 한국해양학회지:바다
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• 제14권2호
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• pp.118-126
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• 2009

저서규조류는 하구역 먹이망을 이해하는 데 중요한 생물로서 그들의 광생리 특성에 따라 일차생산력이 크게 변화한다. 본 연구에서는 단기간 온도 변화가 저서규조류 4종(Navicula sp., Nitzschia sp., Cylindrotheca closterium, Pleurosigma elongatum)의 광합성 반응에 미치는 영향을 Diving PAM을 이용한 엽록소 형광 분석법으로 측정하여 광생리 특성을 분석하였다. 6개의 온도 조건(10, 15, 20, 25, 30, $35^{\circ}C$)에서 2시간 간격으로 24시간 동안 엽록소 형광을 측정하여 P-I 곡선을 도출하였다. 제2광계의 유효양자수율($\Phi_{PSII}$)은 대부분의 종에 있어서 온도가 증가함에 따라 감소하였으며, 상대 최대 전자전달율(rETRmax)은 최적 온도까지 증가한 후 급격하게 감소하였다. 최대 빛이용 효율($\alpha$)은 다른 광합성 매개변수에 비해 온도에 덜 민감하였으나, 높은 온도에서는 감소하였으며, 광포화 계수($E_K$)는 상대 최대 전자전달율의 반응과 매우 유사하였다. 종별 광생리 특성을 분석한 결과, Navicula sp.와 Cylindeotheca closterium가 광생리적 조절을 통하여 단시간의 온도 변화에 광순응하는 것을 확인할 수 있었다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제9권4호
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• pp.446-459
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• 2017

Naval ships are assigned many and varied missions. Their performance is critical for mission success, and depends on the specifications of the components. This is why performance analyses of naval ships are required at the initial design stage. Since the design and construction of naval ships take a very long time and incurs a huge cost, Modeling and Simulation (M & S) is an effective method for performance analyses. Thus in this study, a simulation core is proposed to analyze the performance of naval ships considering their specifications. This simulation core can perform the engineering level of simulations, considering the mathematical models for naval ships, such as maneuvering equations and passive sonar equations. Also, the simulation models of the simulation core follow Discrete EVent system Specification (DEVS) and Discrete Time System Specification (DTSS) formalisms, so that simulations can progress over discrete events and discrete times. In addition, applying DEVS and DTSS formalisms makes the structure of simulation models flexible and reusable. To verify the applicability of this simulation core, such a simulation core was applied to simulations for the performance analyses of a submarine in an Anti-SUrface Warfare (ASUW) mission. These simulations were composed of two scenarios. The first scenario of submarine diving carried out maneuvering performance analysis by analyzing the pitch angle variation and depth variation of the submarine over time. The second scenario of submarine detection carried out detection performance analysis by analyzing how well the sonar of the submarine resolves adjacent targets. The results of these simulations ensure that the simulation core of this study could be applied to the performance analyses of naval ships considering their specifications.

• 기술혁신연구
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• 제19권2호
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• pp.1-23
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• 2011

일반적으로 직원들이 자신의 경력이 정체되어 있다고 인식하게 되면 직무몰입 및 직무만족도가 낮아지고 이는 궁극적으로 성과에 부정적인 영향을 미치게 된다. 특히, 연구개발 업무와 같이 고도의 전문적인 지식이 필요한 직무에서는 경력개발이 더욱 중요한 의미를 가진다. 기존 연구들이 경력정체성의 부정적 결과에 연구의 초점을 두었다면 본 연구는 경력정체성의 선행요인을 파악하는데 중점을 두고 있다. 본 연구에서는 경력정체성의 선행 요인을 조직수준 변수와 개인수준 변수로 구분한 후 각각의 변수가 경력정체성에 미치는 직접효과 및 변수들간의 상호작용 효과를 분석하였다. 국내 정부출연연구소 연구원 및 행정직을 대상으로 실증 분석한 결과, 경력개발제도와 타 기관 근무경험은 경력정체성과 부(-)의 관계를 보였으며, 연령은 경력정체성과 정(+)의 관계를 보였다. 또한 경력개발제도와 타 기관 근무경험간의 상호작용도 유의적인 결과를 보였다.

• Journal of Ecology and Environment
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• 제41권3호
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• pp.45-53
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• 2017

Background: There have been many studies on the growth conditions of Zostera marina and Zostera japonica, but few studies have examined how spatial and temporal factors affect growth in established seagrass beds or the distribution range and shoot density. This study aims to clarify the factors that determine the temporal and spatial distribution of Zostera marina and Zostera japonica in the Seto Inland Sea east of Yamaguchi Prefecture. Methods: The study site is in Hiroshima Bay of the Seto Inland Sea, along the east coast of Yamaguchi Prefecture, Japan. We monitored by diving observation to confirm shoot density, presence or absence of both species and observed water temperature, salinity by sensor in study sites. Results: The frequency of occurrence of Zostera marina was high in all seasons, even in water depths of D.L. + 1 to -5 m ($80{\pm}34%$ to $89{\pm}19%$; mean ${\pm}$ standard deviation), but lower (as low as $43{\pm}34%$) near the breakwall, where datum level was 1 to 2 m, and it was further reduced in datum level -5 m and deeper. The frequency of occurrence of Zostera japonica was highest in water with a datum level of +1 to 0 m. However, in datum level of 0 m or deeper, it became lower as the water depth became deeper. Datum level +1 m to 0 m was an optimal water depth for both species. The frequency of occurrence and the shoot density of both species showed no negative correlation. In 2011, the daily mean water temperature was $10^{\circ}C$ or less on more days than in other years and the feeding damage by S. fuscescens in the study sites caused damage at the tips. Conclusions: We considered that the relationship between these species at the optimal water depth was not competitive, but due to differences in spatial distribution, Zostera marina and Zostera japonica do not influence each other due to temperature conditions and feeding damage and other environmental conditions. Zostera japonica required light intensity than Zostera marina, and the water depth played an important role in the distribution of both species.

• 디지털융복합연구
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• 제16권9호
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• pp.29-37
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• 2018

본 연구는 직장인들의 자기주도적 학습에 영향을 미치는 요인을 파악하는 데 연구의 목적을 두었다. 이를 위하여 충청남도 서북부 2개의 시에서 직장인 335명을 대상으로 하여 설문조사를 실시하였다. 결과 분석은 일반적 특성에 따른 자기주도적 학습의 차이 검정(T-test, ANOVA), 주요 변인 간의 상관분석, 그리고 희망과 성장 마인드셋이 자기주도적 학습에 미치는 영향을 파악하기 위하여 집단을 사원급과 대리급 이상으로 나누어 위계적 회귀분석을 실시하였다. 주요한 연구결과는 다음과 같다. 첫째, 자기주도적 학습은 성별에 따라 차이를 보였다. 둘째, 상관분석 결과 희망과 성장 마인드셋 및 자기주도적 학습은 모두 정적 상관관계를 나타내었다. 셋째, 회귀분석 결과 사원급인 경우 희망의 경로사고와 성장 마인드셋의 지능이 자기주도적 학습에 영향을 미쳤고 대리급 이상인 경우 희망의 경로사고가 영향을 미치는 것으로 나타났다. 끝으로 직위에 따라 자기주도적 학습을 높이기 위한 정책적 방안을 논의하였다.

• 대한조선학회논문집
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• 제47권4호
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• pp.628-645
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• 2010

To perform the engagement level simulation between the underwater vehicle model and the surface model those are constituted with various systems/ sub-systems, we implemented four different federates as a federation according to the IEEE 1516 HLA (High Level Architecture) protocol that is the international standard in the distributed simulation. Those are CFCS (Command and Fire Control System) federate, motion federate, external entities (torpedos, countermeasure and surfaceship) federate, and visualization federate that interacts with OSG (Open Scene Graph)-based visualization rendering module. In this paper, we present the detailed method about the model constitution for discrete event simulation in the distributed environment. For the sake of this purpose, we introduce the DEVS (Discrete Event System Specification)-HLA-based modeling method of the CFCS federate that reflects not only the interations between models, but also commands from user and tactics manager that is separated from the model. The CFCS federate makes decisions in various missions such as the normal diving, the barrier misision, the target motion analysis, the torpedo launch, and the torpedo evasion. In the perspective of DEVS modeling, the CFCS federate is the coupled model that has the tactical data process model, command model and fire control model as an atomic model. The message passing and time synchronization with other three federates are settled by the $m\ddot{a}k$ RTI (Runtime Infrastructure) that supports IEEE 1516. In this paper, we provides the detailed modeling method of the complicated model that has hierarchical relationship such as the CFCS system in the submarine and that satisfies both of DEVS modeling method for the discrete event simulation and HLA modeling method for the distributed simulation.

• Journal of Preventive Medicine and Public Health
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• 제22권1호
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• pp.71-80
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• 1989

The adverse effect of diving on the fetus may extend beyond n gestational process and outcome. Primiparous Sprague-Dawley rats were assigned to one of ten exposure schedules during gestatred $PO_2$ level, the following question about the effect of exposing a pregnant female to high partial pressure of inspired oxygen has been raised. 'What effect does an increased maternal $PIO_2$ have on fetal arterial $PO_2$ and therefore on possible fetal oxygen poisoning?' This study was carried out to observe the effects of maternal hyperoxia on gestational process and outcome. Primiparous Sprague-Dawley rats were assigned to one of ten exposure schedules during gestation. The treatment groups were subjected to either the high concentration of oxygen, or the high atmospheric pressure. On day 21 of gestation, laparotomy was performed to examine for number and distribution of implantations and live and resorbing embryos. Fetuses were weighed, and examined for gross malformations. Subsequently, they were fixed, measured in physical parameters, and examined for visceral anomalies. Minor visceral anomalies and anatomical variation was not found. Similarily, there were no significant differences when number of resorptions, mean fetal weights, pregnancy interruption rate were compared by analysis of variance. These results indicate that exposing rats to oxygen at increased atmospheric pressure doese not affect fetal health or survival.

• Journal of Advanced Marine Engineering and Technology
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• 제34권1호
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• pp.177-182
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• 2010

인공어초의 구조적 설치로 인하여 흐름의 변화가 생기며, 이로 인한 인공어초 주변의 퇴적물 수송은 침전과 매몰뿐만 아니라 저질 환경에도 영향을 미친다. 본 조사는 경상북도 포항시 해역에 시설된 사각형 어초의 시설상태를 파악하기 위하여 수중음향 영상기기인 사이드 스캔 소나(SSS), 인공위성 위치 측정기(DGPS)와 잠수조사를 통한 조사를 실시하였다. 조사 결과, 총 139개소에서 10,526개의 사각형 어초가 발견되었으며, 어초 기능 유지에 영향을 미치는 수준으로 판단되는 0.5m 이상의 매몰과 세굴은 각각 4개소(0.5~1.2m, 2.9%)와 3개소(0.5m, 2.2%)로 나타났다. 파손의 경우 10,526개의 발견된 사각형 어초 중 183개(1.74%)로 나타났다. 따라서 포항시 해역에 시설된 사각형 인공어초의 시설상태는 비교적 안정적인 것으로 나타났다.