• Title/Summary/Keyword: ocean environmental

검색결과 3,475건 처리시간 0.087초

Changes in Free Oscillation Mode in Isahaya Bay Due to a Barrier

  • Park, Byung-Ho;Yuk, Jin-Hee
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 2003년도 한국해안해양공학발표논문집
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    • pp.259-269
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    • 2003
  • The necessary of predicting changes in tidal regime that would caused by large coastal engineering developments has been led to increased numerical modeling of tides on the continental shelf since 1970s (Flather, 1976; Choi, 1978; Greenberg, 1979). (omitted)

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새만금 방조제 건설에 의한 황해 조류체계의 교란 (Perturbation in Yellow Sea Tidal Current Regime due to Barrier Construction at Saemangeum)

  • Park, Byung-Ho;Lee, Han-Soo
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 2003년도 한국해안해양공학발표논문집
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    • pp.143-153
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    • 2003
  • The necessity of predicting changes in tidal regime that would be caused by large coastal engineering developments has been led to increased numerical modeling of tides on the continental shelf since 1970s (Flather 1976; Choi 1978; Greenberg 1979). (omitted)

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수면에 거치된 수직 다중 판에 의한 산란에서 와류로 인한 파랑 에너지의 소멸 (Vortex-Shedding-Induced Dissipation of Waves Scattering against Surface-Piercing Vertical Thin Plates)

  • Oh, Mi-Ran;Lee, Jung-Lyul
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 2003년도 한국해안해양공학발표논문집
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    • pp.276-282
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    • 2003
  • The breakwater of surface-piercing type has been developed mainly for application within bays or estuaries that are semi-protected from the direct impact of targe waves. Most of bays have soft foundation which is too weak to bear the weight of gravity type breakwater. (omitted)

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Prediction of Harbour Resonance by the Finite Difference Approach

  • Lee, Jung-Lyul;Park, Chan-Sung
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 1998년도 정기학술강연회 발표논문 초록집 Annual Meeting of Korean Society of Coastal and Ocean Engineers
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    • pp.124-129
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    • 1998
  • When the strong wind or long wave energy is transferred into the water body of a harbour, the harbour exhibits oscillatory resonant motions which often cause significant damage to moored ships and navigation hazards. Therefore, a number of theoretical and numerical investigations of such resonant oscillations have been carried out but most of them were limited to harbours connected with open sea of constant depth. (omitted)

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An Improved Approach to Identify Bacterial Pathogens to Human in Environmental Metagenome

  • Yang, Jihoon;Howe, Adina;Lee, Jaejin;Yoo, Keunje;Park, Joonhong
    • Journal of Microbiology and Biotechnology
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    • 제30권9호
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    • pp.1335-1342
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    • 2020
  • The identification of bacterial pathogens to humans is critical for environmental microbial risk assessment. However, current methods for identifying pathogens in environmental samples are limited in their ability to detect highly diverse bacterial communities and accurately differentiate pathogens from commensal bacteria. In the present study, we suggest an improved approach using a combination of identification results obtained from multiple databases, including the multilocus sequence typing (MLST) database, virulence factor database (VFDB), and pathosystems resource integration center (PATRIC) databases to resolve current challenges. By integrating the identification results from multiple databases, potential bacterial pathogens in metagenomes were identified and classified into eight different groups. Based on the distribution of genes in each group, we proposed an equation to calculate the metagenomic pathogen identification index (MPII) of each metagenome based on the weighted abundance of identified sequences in each database. We found that the accuracy of pathogen identification was improved by using combinations of multiple databases compared to that of individual databases. When the approach was applied to environmental metagenomes, metagenomes associated with activated sludge were estimated with higher MPII than other environments (i.e., drinking water, ocean water, ocean sediment, and freshwater sediment). The calculated MPII values were statistically distinguishable among different environments (p < 0.05). These results demonstrate that the suggested approach allows more for more accurate identification of the pathogens associated with metagenomes.

수산·해운계 고등학교 교과의 해양환경 내용분석 (The Contents Analysis of Ocean Environment of Textbooks for Fisheries and Marine High School students)

  • 김삼곤;김종화
    • 수산해양교육연구
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    • 제16권2호
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    • pp.143-155
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    • 2004
  • The aims of this study are to analysis about the contents associated with the ocean environment compared 17 special-subject textbooks to 2 common-subject textbooks, and to make some proposals for construction of contents. The results of it are as follows; 1. Only 17 books among 36 textbooks taught by the fisheries and marine high schools are contained to some contents related with ocean environment. The contents associated with the ocean environment take possession of 90%, 62% each of total pages in the textbooks, 'ocean pollution' and 'ocean environment'. 2. Of compulsory texts, namely, 'general fisheries', 'general ocean' and 'information treatment of fisheries-marine', the former 2 books are composed of 4.5%, 36.2% each relating with ocean environment. But the last one is nothing. 3. Therefore, even a little contents of ocean environment and its conservation, it is necessary to add as the reasonable rate to the characteristics of each book in 36 special-subject textbooks. 4. And also it is shown that the common-subject textbooks,'ocean science', ' earth science I' and 'earth science II', are composed of 35.7%, 10%, 16.7% each. So we'd like to recommend that the contents of ocean pollution and environmental conservation have to add more.

접합대순환모형의 초기조건 생산방법에 따른 북반구 겨울철 기온과 해수면 온도의 계절 예측성 비교 연구 (Comparative Study on the Seasonal Predictability Dependency of Boreal Winter 2m Temperature and Sea Surface Temperature on CGCM Initial Conditions)

  • 안중배;이준리
    • 대기
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    • 제25권2호
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    • pp.353-366
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    • 2015
  • The impact of land and ocean initial condition on coupled general circulation model seasonal predictability is assessed in this study. The CGCM used here is Pusan National University Couple General Circulation Model (PNU CGCM). The seasonal predictability of the surface air temperature and ocean potential temperature for boreal winter are evaluated with 4 different experiments which are combinations of 2 types of land initial conditions (AMI and CMI) and 2 types of ocean initial conditions (DA and noDA). EXP1 is the experiment using climatological land initial condition and ocean initial condition to which the data assimilation technique is not applied. EXP2 is same with EXP1 but used ocean data assimilation applied ocean initial condition. EXP3 is same with EXP1 but AMIP-type land initial condition is used for this experiment. EXP4 is the experiment using the AMIP-type land initial condition and data assimilated ocean initial condition. By comparing these 4 experiments, it is revealed that the impact of data assimilated ocean initial is dominant compared to AMIP-type land initial condition for seasonal predictability of CGCM. The spatial and temporal patterns of EXP2 and EXP4 to which the data assimilation technique is applied were improved compared to the others (EXP1 and EXP3) in boreal winter 2m temperature and sea surface temperature prediction.

신경망을 이용한 유조선 기름 유출사고에 따른 환경비용 추정에 관한 연구 (Estimation of Environmental Costs Based on Size of Oil Tanker Involved in Accident using Neural Network)

  • 신성철;배정훈;김현수;김성훈;김수영;이종갑
    • 한국해양공학회지
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    • 제26권1호
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    • pp.60-63
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    • 2012
  • The accident risks in the marine environment are increasing because of the tendency to build faster and larger ships. To secure ship safety, risk-based ship design (RBSD) was recently suggested based on a formal safety assessment (FSA). In the process of RBSD, a ship designer decides which risk reduction option is most cost-effective in the design stage using a cost-benefit analysis (CBA). There are three dimensions of risk in this CBA: fatality, environment, and asset. In this paper, we present an approach to estimate the environmental costs based on the size of an oil tanker involved in an accident using a neural network. An appropriate neural network model is suggested for the estimation,and the neural network is trained using IOPCF data. Finally,the learned neural network is compared with the cost regression equation by IMO MEPC 62/WP.13 (2011).

모형실험을 통한 모래지반에서 석션버켓기초의 관입저항력 평가 (Investigation on the Penetration Resistance of Suction Bucket Foundation in Sand using Model Test)

  • 김근수;권오순;오명학;장인성
    • 한국지반환경공학회 논문집
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    • 제15권6호
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    • pp.75-83
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    • 2014
  • 석션버켓기초는 펌프로 버켓 내부의 물을 외부로 배출할 때 발생한 압력차로 지반에 설치되는 기초이다. 버켓기초는 외해의 플랫폼이나 석유 가스 시추시설을 계류시키기 위한 앵커로 주로 사용되었으나, 최근 유럽을 중심으로 해상풍력발전의 기초로 적용되기 시작하면서 국내에서도 큰 관심을 받고 있다. 석션버켓기초의 관입저항력 산정은 석션버켓기초를 성공적으로 시공하기위해 고려해야 할 주요 사항 중의 하나이다. 본 연구는 석션버켓기초를 관입시킬 때 필요한 관입력을 평가하기 위해 실내모형실험을 수행하였다. 실내모형실험은 압입설치 및 석션설치에서 측정한 관입저항력을 관입성능평가에서 많이 사용되는 기존의 이론식과 비교하여 강도감소계수의 적절한 범위를 검토하였다.

Spatial-Temporal Distribution Characteristics of Bigeye and Yellowfin Tunas in Kiribati Waters

  • Taanga, Aketa Mature;Cai, Yi-Hui;Lu, Hsueh-Jung;Ni, I-Hsun
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.174-179
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    • 2006
  • Information on the distribution characteristics of tuna resources in Kiribati EEZ waters in three zones (Zone 1: west Gilbert region, Zone 2: central Phoenix region, and Zone 3: east Line region) as well as their relationship with the ocean environment is critical for sustainable managing the migratory tuna resource and fishing practices in this region. Therefore, this study is designed to investigate the spatial and temporal distribution and concentration of bigeye (BET) and yellowfin tuna (YFT) in Kiribati EEZ waters in relation to sea surface temperature (SST) and thermocline depth so as to better understand the tuna resources management basis in Kiribati waters. The geographic and temporal distribution and concentration were first displayed. Paired t-test was utilized to compare the distribution between the two tuna species based on Catch per Unit Effort (CPUE) derived from the Korean longliners during 1996 to 2004, and also among the three zones of Kiribati EEZ waters. Environmental conditions of the three zones were then compared and correlated with the CPUE of YFT and BET. In addition, the effect of ENSO phenomena on the environmental conditions and the distribution of YFT and BET within the three zones were also examined. The BET was relatively higher in the Zone 3 whereas YFT predominate in the Zone 1 and the Zone 2 due to oceanographic differences among the three zones and the ecological habitats of the two tuna species. It was suggested that El Ni?o/Southern Oscillation (ENSO) phenomena altered the oceanographic conditions of the three zones that in turn change the distribution of the two tuna species. During El Ni?o, the warm phase of ENSO, resulted in having more BET in all the three zones and the opposite observed during La Ni?a (cold phase) replacing by having relatively higher catch rate for YFT, particularly in the Zone 2. Although the results of the study are from short periods (1996 to 2004) in considering oceanographic anomality, these environmental variations should be considered into sustainable fisheries management of tuna fisheries in Kiribati EEZ waters.

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