• 제목/요약/키워드: The last Sea

검색결과 402건 처리시간 0.026초

Research and Anaysis of Wave Energy Characteristic for Wave Generation System

  • Oh Jin-Seok
    • Journal of Advanced Marine Engineering and Technology
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    • 제30권4호
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    • pp.520-526
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    • 2006
  • Wave Energy is a derivative of the solar energy input to the earth, which is accumulated on open water surfaces by the action of the winds Waves are disturbances in the water surface. This paper is interested primarily in progressive waves, which carry energy from one place to another Waves are irregular in size and frequency. Moreover the surface of the sea is one of the most hostile environments for engineering structures and materials. The idea of harnessing the tremendous power of the ocean's waves is not new. Hundreds of wave energy conversion techniques have been suggested over the last two centuries. Although many WECS (Wave Energy Conversion Systems) have been invented, only a few systems have been tested and evaluated. This paper describes the characteristic of WES (Wave Energy System) in terms of, devices, resource and potential, etc.. Finally, this paper provides a summary of general and specific conclusions and recommendations concerning WECS potential in Korea.

초음파를 이용한 해저면 영상화 기법에서의 Gain Control에 관한 연구 (A Study on the Gain Control for Underwater Side Scan Sonar System)

  • 이철원;오영석;우종식
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2000년도 추계학술대회 논문집
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    • pp.216-221
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    • 2000
  • This paper deals with the Gain Control in the processing of the underwater acoustic image obtained from side scan sonar(SSS) system. At first, this paper describes the principles of SSS that is a surveying equipment for the underground of the rivers or dams as well as sea floor. Then this paper analyzes the cause and effects of the time varying intensity from the view point of transmission loss and beam pattern. At last, the time varying gain filter that is adopted by the towfish is introduced.

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해상보안체제(ISPS Code)의 도입 방향에 관한 연구 (A Study on the Introduction of Maritime Security System(ISPS Code))

  • 노창균
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2003년도 춘계학술발표회
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    • pp.7-15
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    • 2003
  • This paper is intended as an investigation of introduction of Maritime Security System. In the last few years, several articles have been devoted to the study of ISPS Code(International Code for the Security of Ships and of Port Facilities). The Diplomatic Conference on Maritime Security held in London in December 2002 adopted new provisions in the International Convention for the Safety of Life at Sea, 1974 and this ISPS Code to enhance maritime security. These new requirements form the international framework through which ships and port facilities can co-operate to detect and deter acts which threaten security in the maritime transport sector. Accordingly, the purpose of this paper is to suggest an introduction of Maritime Security System and understanding of ISPS Code.

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지진 매개변수에 따른 지진해일 초기 수면 (Initial Free Surface Profile of Tsunamis by Earthquake Parameters)

  • 조용식;김재홍;손대희;김성민
    • 한국방재학회 논문집
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    • 제6권2호
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    • pp.61-68
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    • 2006
  • 지진 매개변수에 의해 지진해일의 초기 수면형상이 결정된다. 본 연구에서는 해저지진에 의해 발생하는 지진해 일의 초기 수면형상의 변화에 대한 지진 매개변수의 영향을 연구한다. 대상 지진해일은 지난 수십 년 동안 우리나라에 가장 큰 피해를 입힌 1983년 동해 중부 지진해일이다. 지진 매개변수 중에서는 strike angle(${\theta}$)이 초기수면형상에 가장 큰 영향을 주었다.

Wave height from satellite altimetry and its comparison with ECMWF product

  • Kim, Seung-Bum;Cotton, P.David
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.337-340
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    • 2002
  • Monitoring of wave height is important primarily to reduce storm risks at sea and along the coast. Wave heights in recent years have increased 50% for the last 40 years, thus requiring intensive monitoring. Satellite altimetry offers a powerful tool for regular and extensive monitoring of the wave height. We extracted significant wave height (SWH) using several altimeter missions from 1987-1995 over the Northwest Pacific and compared with ECMWF reanalysis (ERA) products. For large wave heights > 2.5 m, the ERA wave heights are smaller than the altimetric ones, while for small wave heights the ERA wave heights are larger. Comparison in SWH between altimetric derivations and ERA model products shows the discrepancy of 0.46-0.21$\times$SWH(m).

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Fuzzy Multi Criteria Evaluation for Performance of Vietnam Container Shipping Companies (Focussing on domestic companies including to previous study)

  • NGO, Phuong Thao;YOON, Dae-Gwun;KEUM, Jong-soo
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2017년도 공동학술발표회
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    • pp.166-166
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    • 2017
  • Nowadays, container transport services play a substantial role in global cargo transportation by serving as an intermodal between the exporter and importer. Container shipping has become increasingly important over the past few decades due to its obvious advantages. However, Vietnam's container market has shown severely ongoing competition among numerous domestic and foreign shipping lines resulting in serious consequences occurring such as the freight rates substantially decreasing within the last ten years. In fact, Vietnam's sea lanes have become more defensive to cover the losses of shipping companies. Selection of criteria for competitive evaluation of container transport companies is necessary to help recognize the problems within the enterprise especially relating to its position in the market and from here, business management are able to put strategic plans in place and reasonable policy in order to be able to survive and grow.

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Bilinear mode predictive control methods for chemical processes

  • Yeo, Yeong-Koo;Oh, Sea Cheon;Williams, Dennis C.
    • 제어로봇시스템학회지
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    • 제2권1호
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    • pp.59-71
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    • 1996
  • In the last decade, the model predictive control methods have enjoyed many industrial applications with successful results. Although the general predictive control methods for nonlinear chemical processes are not yet formulated, the promising features of the model predictive control methods attract attentions of many researchers who are involved with difficult but important nonlinear process control problems. Recently, the class of bilinear model has been introduced as an useful tool for examining many nonlinear phenomena. Since their structural properties are similar to those of linear models, it is not difficult to develop a robust adaptive model predictive control method based on bilinear model. We expect that the model predictive control method based on bilinear model will expand its region in the world of nonlinear systems.

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바다목장화를 위한 다목적 수산기지의 기초설계 (Basic Design of Multipurpose Fisheries Base for Marine Ranching Program)

  • 김현주;이나리
    • 한국해양공학회지
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    • 제13권4호통권35호
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    • pp.143-150
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    • 1999
  • Multipurpose fisheries base was conceptually designed to establish marine ranching system in the coastal waters around Tongyoung, southern sea of Korea. Fisheries base for marine ranching system has integrated various facilities which were required for the process of spawning, rearing, training, releasing, monitoring and catching functions. This base has five steel piles for supporting upper structure and systems. Four steel piles are surrounded by circular net pen made by steel wire, they have the function of the protection against fouling for pile and scouring for bottom soil as well as secondary rearing and short stocking. We can use the last pile to moor a ship and access to the base. Principal structure with steel piles is designed by optimization technique considering design external forces in the coastal waters of return period of 50 years. Design optimization Problem is formulated for this base. Optimal design of multipurpose fisheries base is numerically investigated by sequential quadratic programming method.

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Fuzzy AHP Evaluation for Performance of Container Shipping Companies in Vietnam (Developing on the Model of Previous Study for the Domestic Lines)

  • Yoon, Dae-Gwun;Ngo, Phuong Thao;Keum, Jong-Soo
    • 한국항해항만학회지
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    • 제42권5호
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    • pp.365-370
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    • 2018
  • Currently, container transport services play a substantial role in global cargo transportation, by serving as an intermodal between exporter and importer. Container shipping has become increasingly important over the past few decades, due to obvious advantages. However, Vietnam's container market has shown severely ongoing competition among numerous domestic and foreign shipping lines, resulting in serious consequences occurring such as freight rates substantially decreasing within the last 10 years. Vietnam's sea lanes have become more defensive, to cover losses of shipping companies. Selection of criteria for competitive evaluation of container transport companies is necessary, to facilitate addressing the problems within the enterprise, especially relating to its position in the market and from here, business management can implement strategic plans and reasonable policy, to survive and grow.

제빵과정에 있어서 밀가루 지방질, 쇼트닝 및 유화제의 역할 (A Three Way Contribution of Wheat Flour Lipids, Shortening and Surfactants to Bread-making)

  • 정옥경
    • 한국식품과학회지
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    • 제13권1호
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    • pp.74-89
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    • 1981
  • Breadmaking is a complex system in which many variables govern the production of acceptable bread. Lipids, a minor component of wheat flour, function importantly in bread-making. Shortening, or fat, is one of the essential ingredients in commercial baking. Beneficial shortening effect depends on type and quantity of lipids present in wheat flour and also on wheat flour quality. Surfactants have been used in baking industry during last decade because certrain surfactants can replace shortening and/or natural flour lipids. A proper combination of lipidshortening-surfactant is more useful in the production of specialty breads such as whole wheat breads, high protein breads, high fiber breads or even non-wheat composite breads rather than in the production of regular white breads. This presentation is a review of recent studies on the contribution of flour lipids, shortening, and surfactants, alone or in combination in the production of breads; illustrations are mainly from data obtained in the author's laboratory.

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