• 제목/요약/키워드: marine structure

검색결과 2,408건 처리시간 0.025초

A Study on Restructuring of the Marine Products Value Chain and the Development of E-commerce Trading Systems in the Ubiquitous Environment (유비쿼터스 환경에서의 해양수산물 유통 가치사슬 혁신 및 전자상거래 시스템 구축에 관한 연구)

  • Pak, Myong-Sop;Kim, Jong-Uk;Lee, Won-Jun;Park, Sang-Cheol
    • Journal of Information Technology Services
    • /
    • 제5권2호
    • /
    • pp.125-136
    • /
    • 2006
  • In general, the distribution structure of marine products is very vulnerable to the uncertainties in the process from the production to the sale, and a lot of difficulty is thus inevitable in the supply control. Such a distribution structure is a very critical issue in securing the suability of marine products through systematic quality and hygiene control of marine products, and it is thus time to discuss the method to innovate and restructuring the distribution structure of marine products. From this point of view, this study approached the flow from production to consumption in view of SCM(supply chain management) beyond the partial discussion conducted so far for the distribution structure in the field of marine products. Further, this study suggested the establishment of electronic commerce systems with a traceability system built in RFID for marine products as an alternative of redesigning distribution infrastructure in the ubiquitous environment. From the results, we assured that such an electronic commerce system would be a new measure to improve the structure currently causing inefficiency and excessive distribution cost for the distribution structure of marine products.

On the characteristics of the motion and the mooring force of a mid-layer type floating structure in waves

  • Miyahara, Rie;Shoji, Kuniaki;Mita, Sigeo;Nagase, Risa
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 한국항해항만학회 2004년도 Asia Navigation Conference
    • /
    • pp.226-234
    • /
    • 2004
  • In this study experiments are conducted with a mid-layer type structure. This structure can operate not only at water surface but also in water. Six degrees of freedom oscillations of the structure and mooring force were measured by model experiments. From these experiments, it was shown that the lattice model has two peaks in the surge response curve and the oscillation amplitude and mooring forces increase according to the distance of separation between water level and upper deck.

  • PDF

Study of the Effect of Crankshaft Model in Shaft Alignment Analysis (추진축계 정렬해석에서 엔진내부 축 모델의 영향에 관한 연구)

  • Kim Kwang Seok;Yeun Jung Hum;Kang Joong Kyoo;Heo Joo Ho
    • Special Issue of the Society of Naval Architects of Korea
    • /
    • 대한조선학회 2005년도 특별논문집
    • /
    • pp.206-210
    • /
    • 2005
  • As design trends has changed to have flexible aft hull structure, increased power output and stiffer shafting system, owners and classification societies have more concerned about shaft alignment. In the shaft alignment analysis, there are many uncertainties which are related in propeller generated force, bearing stiffness, crank shaft model and etc. in this study, it is focused on the effect of crankshaft model by comparing between equivalent model and actual crankshaft model.

  • PDF

Stability Analysis of Marine Structure Foundation Constructed by Deep Mortar Piles (심층몰탈파일로 조성된 항만구조물 기초의 안정성 검토)

  • 천병식;여유현;김경민;양진석;김도식
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • 한국해양공학회 2001년도 춘계학술대회 논문집
    • /
    • pp.228-233
    • /
    • 2001
  • In this case study, under conideration of field situations, such as increase of water level, height increment of the marine structure, dredging and backfill, the stability analysis of sliding and lateral flow of the marine structure in OOOharbor was carried out, and foundation reinforcement methods was presented. based on the results of site investigation, the stability analysis of slope sliding and lateral flow was performed as following. In section BH-1, 2, the analysis was performed in two cases that the marine structure was heightened and filled, and not heightened and filled. In section BH-1, 4, heightened and filled. The analysis results showed that the stabilities of slope sliding and lateral flow in section BH-1, 2, 3, 4 were unstable. After additional reinforcements with Deep Mortar Pile, the stabilities in section BH-1, 2, 3, 4 were evaluated as efficiently large.

  • PDF

A Study on Duty Competency and Utilizing Package Development for Construction of Marine Terminal Structure (해양터미널구조물설치분야 직무능력 및 활용패키지 개발에 대한 연구)

  • PARK, Jong-Un;KANG, Beodeul;BAEK, In-Hum
    • Journal of Fisheries and Marine Sciences Education
    • /
    • 제28권2호
    • /
    • pp.456-464
    • /
    • 2016
  • NCS development for construction of marine terminal structure was carried out through following procedures such as analysis on characteristics, analysis on duty, development of the first draft for standards, validation of industry sites, duty competency standards through expert committee, and utilizing package. The results were as follows. Firstly, duty competency was classified as levels from 3 to 7. Educational training institutions were followed by 22 universities, 21 colleges, 16 graduate schools, and 10 high schools. Secondly, developed standards were consisted of duty and competency unit. The name of duty was construction of marine terminal structure and competency units were consisted of 9 items as survey on economic effect, evaluation of conditions on construction environment, plan for construction of structure, construction of transfer, mooring, and power equipment, and construction, startup test, and maintenance of terminal structure. 33 competency unit elements below 9 competency units were developed. Thirdly, utilizing package was developed into 3 areas of life-long career path, training criteria, and guidelines for exam according to national competency standards for in order to develop development of labor's career and perform personal management such as hiring and promotion in industry sites.

Pelagic larval dispersal habits influence the population genetic structure of clam Gomphina aequilatera in China

  • Ye, Yingying;Fu, Zeqin;Tian, Yunfang;Li, Jiji;Guo, Baoying;Lv, Zhenming;Wu, Changwen
    • Genes and Genomics
    • /
    • 제40권11호
    • /
    • pp.1213-1223
    • /
    • 2018
  • Pelagic larval dispersal habits influence the population genetic structure of marine mollusk organisms via gene flow. The genetic information of the clam Gomphina aequilatera (short larval stage, 10 days) which is ecologically and economically important in the China coast is unknown. To determine the influence of planktonic larval duration on the genetic structure of G. aequilatera. Mitochondrial markers, cytochrome oxidase subunit i (COI) and 12S ribosomal RNA (12S rRNA), were used to investigate the population structure of wild G. aequilatera specimens from four China Sea coastal locations (Zhoushan, Nanji Island, Zhangpu and Beihai). Partial COI (685 bp) and 12S rRNA (350 bp) sequences were determined. High level and significant $F_{ST}$ values were obtained among the different localities, based on either COI ($F_{ST}=0.100-0.444$, P<0.05) or 12S rRNA ($F_{ST}=0.193-0.742$, P<0.05), indicating a high degree of genetic differentiation among the populations. The pairwise $N_m$ between Beihai and Zhoushan for COI was 0.626 and the other four pairwise $N_m$ values were >1, indicating extensive gene flow among them. The 12S rRNA showed the same pattern. AMOVA test results for COI and 12S rRNA indicated major genetic variation within the populations: 77.96% within and 22.04% among the populations for COI, 55.73% within and 44.27% among the populations for 12S rRNA. A median-joining network suggested obvious genetic differentiation between the Zhoushan and Beihai populations. This study revealed the extant population genetic structure of G. aequilatera and showed a strong population structure in a species with a short planktonic larval stage.

An Experimental Study for the Fatigue Strength Assessment of Longi-web Connections (Longi-web 연결부의 피로강도 평가에 관한 실험적 연구)

  • Kang, Sung-Won;Kim, Jeong-Hwan;Kim, Kwang-Seok;Kang, Joong-Kyoo;Heo, Joo-Ho;Kim, Myung-Hyun
    • Journal of the Society of Naval Architects of Korea
    • /
    • 제45권1호
    • /
    • pp.87-92
    • /
    • 2008
  • In the load-carrying fillet weldments, which are common in ship structures, fatigue cracks can occur at the weld root, in addition to the weld toe. In particular, fatigue cracks originating from the weld root are difficult to detect and cause a significant reduction in the fatigue strength of a weldment. Therefore, it is important to note the fatigue failure mode of load-carrying fillet weldment. In this study, a series of fatigue test was carried out for the fatigue strength evaluation of longi-web connections that are typical kinds of the load-carrying fillet weldment.

Biodiversity and Community Structure of Marine Benthic Organisms in the Rocky Shore of Dongbaekseom, Busan

  • Yoo, Jong-Su
    • ALGAE
    • /
    • 제18권3호
    • /
    • pp.225-232
    • /
    • 2003
  • Species composition, community structure and biodiversity of marine benthic community were studied in the rocky shore of Dongbaekseom, Busan. A total of 82 species of marine algae including 4 Cyanophyta, 11 Chlorophyta, 20 Phaeophyta and 47 Rhodophyta are listed. The dominant algal species were Ulva pertusa, Chondria crassicaulis, Corallina spp. and Melobesioidean algae. Sargassum thunbergii, Chondracanthus intermedia, Gelidium divaricatum and Ralfsia verrucosa were subdominant in cases of different seasons and vertical layers. Chthamalus challengeri, Littorina brevicula and Mytilus edulis were dominant zoobenthic species upper-middle layer of the intertidal zone. The community structure of this area seemed to be controlled by spatial competition with benthic marine algae. The species diversity indices estimated from different sources were quite different. Indices from coverage were 1.87, 3.98 from frequency, 2.26 from the average of total frequency and coverage and 2.15 from importance value. The similarity indices on the present study showed decreasing trends comparing to the previous benthic algal composition researches.

A New Analog of Antimycin from Streptomyces sp. M03033

  • Seo, Young-Wan;Cho, Ki-Woong;Rho, Jung-Rae;Mo, Sang-Jun;Shin, Jong-Heon
    • Journal of Microbiology and Biotechnology
    • /
    • 제11권4호
    • /
    • pp.663-667
    • /
    • 2001
  • A new secondary metabolite was isolated from the culture broth and mycelium of Streptomyces sp. collected from marine sediment. The structure of this compound was determined to be N-formylantimycic acid methyl ester, an acyclic derivative of antimycin, on the basis of combined chemical and spectral methods. The structure-activity relationship of antimycins is discussed.

  • PDF