• Title/Summary/Keyword: ocean conditions

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A study on Insurance Indemnity of Salvage award. (해난구조비의 보험보상에 관한 연구)

  • 이학헌
    • Journal of the Korean Institute of Navigation
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    • v.18 no.2
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    • pp.129-149
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    • 1994
  • Sea casualties may happen in ship, cargo and the others concerned with sea transportation. : the shipo-wer, marine insurer and salvage company have been endeavored to compensate salvage award with some rule and regulation such as Marine Insurance Act, York Antwerp Rules and Average adjustment rules. Once sea casualties happened, the salvage contract is established between the owners, marine insurance and salvage company, the contract are divided into so many kinds of them. In this paper, we have an analysis on the character of the salvage contract whether the characteristic contents of them are in benefit to any party or not. In this connection with these positive or negative character of the contract, it is worthwhile to compare the actual salvage expenses contract with no cure no pay contract. LOF 1990 has been revised recently, which is based on no cure no pay, expecially, the special compensation, safety net clause of LOF 1990 could be understood in the view of the prevention of sea pollution and the preservation of sea circumstances in the world. Salvage has the complicated and quality, because the adjustment of almost salvage charges have been treated through the other sea casualties which is accompanied by and mixed with. Besides of the importance of salvage contracts, we are in need to understand that what the diversified character of salvage charges are. Furthermore the owners should carefully select the insured conditions on Hull Insurance according to the type of his company, operating ocean route, loading cargo and etc. In this paper, we would try to analyze the character of the salvage award such as General Average, Sue and Labour Charges and Particular charges. We would like to propose that the uniformed system of the salvage award. Compensation should be built up for the effective and efficient salvage operation and for reducing the claims and conflicts from the concerned parties. To this end, we could expect that the uniformed system for salvage award compensation will come to be the benefit of all owners, insurers, salvage company.

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A study for roll damping performance of a platform supply vessel with or without bilge keel using CFD (전산유체역학을 이용한 해양작업지원선의 빌지킬 유무에 따른 횡동요 성능에 관한 연구)

  • Seok, Jun;Kim, Sung-Yong;Yang, Young-Jun;Jin, Song-Han;Park, Jong-Chun
    • Journal of Advanced Marine Engineering and Technology
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    • v.40 no.9
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    • pp.791-798
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    • 2016
  • In this study, numerical simulations on the effects of bilge keel on roll motion were conducted. The numerical simulations were performed on a 110 m class PSV using the commercial viscous flow analysis software Star-CCM+. Before conducting the study on the 110 m class PSV, an additional simulation of DTMB 5512 was performed and compared with the experimental results to validate the feasibility of the numerical simulation. In the simulation on PSV, a nondimensional damping coefficient was calculated using a free roll decay simulation, and the response amplitude operator (RAO) for the roll motion was calculated with a nondimensional damping coefficient at two conditions (with/without bilge keel).

Comparative Study of Approximate Optimization Techniques in CAE-Based Structural Design (구조 최적설계를 위한 다양한 근사 최적화기법의 적용 및 비교에 관한 연구)

  • Song, Chang-Yong;Lee, Jong-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.11
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    • pp.1603-1611
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    • 2010
  • The comparative study of regression-model-based approximate optimization techniques used in the strength design of an automotive knuckle component that will be under bump and brake loading conditions is carried out. The design problem is formulated such that the cross-sectional sizing variables are determined by minimizing the weight of the knuckle component that is subjected to stresses, deformations, and vibration frequency constraints. The techniques used in the comparative study are sequential approximate optimization (SAO), sequential two-point diagonal quadratic approximate optimization (STDQAO), and approximate optimization based on enhanced moving least squares method (MLSM), such as CF (constraint feasible)-MLSM and Post-MLSM. Commercial process integration and design optimization (PIDO) tools are utilized for the application of SAO and STDQAO. The enhanced MLSM-based approximate optimization techniques are newly developed to ensure constraint feasibility. The results of the approximate optimization techniques are compared with those of actual non-approximate optimization to evaluate their numerical performances.

Enhancement of Bearing Estimation Performance at Endfire Using Cardioid Inverse Beamforming (좌우분리 역빔형성 기법에 의한 센서 축방향의 방위탐지 성능 향상)

  • 강성현;김의준;윤원식
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.1
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    • pp.21-29
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    • 2001
  • In order to detect the precise port/starboard direction of arrival of target signal in real noisy ocean environments, Inverse beamforming (IBF) algorithm is surveyed theoretically and the detection performances of IBF are analyzed with simulations. Cardioid Inverse beamforming algorithm was proposed for port/starboard discrimination and the performance was studied with simulations. It is shown that IBF has a 3dB array gain advantage over Conventional beamforming (CBF) under ideal conditions. This 3 dB advantage is proven theoretically and illustrated with simulations. The fact that the IBF beamwidth is narrower than the CBF beamwidth by a factor of 0.68 proves the performance of defection and spatial resolution improvement. Comparing the simulation results of Cardioid Inverse beamforming and Conventional Cardioid beamforming, it is shown that Cardioid Inverse beamformer has enhanced performance in minimum detection level, detection accuracy and resolution. Due to the results of moving target bearing detection test in endfire, it is shown that Cardioid Inverse beamformer has better performance, comparing the Conventional Cardioid beamformer.

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Dimension Reduction of Solid Models by Mid-Surface Generation

  • Sheen, Dong-Pyoung;Son, Tae-Geun;Ryu, Cheol-Ho;Lee, Sang-Hun;Lee, Kun-Woo
    • International Journal of CAD/CAM
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    • v.7 no.1
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    • pp.71-80
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    • 2007
  • Recently, feature-based solid modeling systems have been widely used in product design. However, for engineering analysis of a product model, an ed CAD model composed of mid-surfaces is desirable for conditions in which the ed model does not affect analysis result seriously. To meet this requirement, a variety of solid ion methods such as MAT (medial axis transformation) have been proposed to provide an ed CAE model from a solid design model. The algorithm of the MAT approach can be applied to any complicated solid model. However, additional work to trim and extend some parts of the result is required to obtain a practically useful CAE model because the inscribed sphere used in the MAT method generates insufficient surfaces with branches. On the other hand, the mid-surface ion approach supports a practical method for generating a two-dimensional ed model, even though it has difficulties in creating a mid-surface from some complicated parts. In this paper, we propose a dimension reduction approach on solid models based on the midsurface abstraction approach. This approach simplifies the solid model by abbreviating or removing trivial features first such as the fillet, mounting, or protrusion. The geometry of each face is replaced with mid-patches from the simplified model, and then unnecessary topological entities are deleted to generate a clean ed model. Also, additional work, such as extending and stitching mid-patches, completes the generation of a mid-surface model from the patches.

Effects of Sediment Improvements with Peat Moss on the Blood Properties of Blood Cockle, Tegillarca granosa (토탄을 이용한 저질개선제가 꼬막 Tegillarca granosa의 혈액학적 성상에 마치는 영향)

  • Lee, Kyoung-Seon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.16 no.1
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    • pp.43-48
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    • 2010
  • This study was designed to evaluate whether the addition of sediment improvements with natural materials to water tanks influenced the hematologic properties and muscle glycogen content of the blood cockle, Tegillarca granosa under laboratory conditions. Following a 10-d matured period of sediment improvements, blood cockles were subjected to 4 groups (0, 100, 300, $800\;g/m^2$) of sediment improvements for 14-d Only one individual died at $800g/m^2$ after 48-h Whole blood, hematocrit value and hemoglobin concentration of blood cockle were changed little by sediment improvements, however, both glucose and glycogen were increased more compared with those of the control groups.

Cooperative control system of the floating cranes for the dual lifting

  • Nam, Mihee;Kim, Jinbeom;Lee, Jaechang;Kim, Daekyung;Lee, Donghyuk;Lee, Jangmyung
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.10 no.1
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    • pp.95-102
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    • 2018
  • This paper proposes a dual lifting and its cooperative control system with two different kinds of floating cranes. The Mega-erection and Giga-erection in the ship building are used to handle heavier and wider blocks and modules as ships and off-shore platforms are enlarged. However, there is no equipment to handle such Tera-blocks. In order to overcome the limit on performance of existing floating cranes, the dual lifting is proposed in this research. In the dual lifting, two floating cranes are well-coordinated to add up the lift capabilities of both cranes without any loss such that virtually a single crane is lifting, maneuvering and unloading. Two main constraints for the dual lifting are as follows: First, two barges of floating cranes should be constrained as a rigid body not to cause a relative motion between two barges and main hooks of the two cranes should be controlled as main hooks of a single crane. In order words, it is necessary to develop the cooperative control of two floating cranes in order to sustain a center of gravity of the module and minimize the tilting angle during the lifting and unloading by the two floating cranes. Two floating cranes are handled as a master-slave system. The master crane is able to gather information about all working conditions and make a decision to control the individual hook speed, which communicates the slave crane by TCP/IP. The developed control system has been embedded in the real floating crane systems and the dual lifting has been demonstrated five times at SHI shipyard in 2015. The moving angles of the lifting module are analyzed and verified to be suitable for hoisting control. It is verified that the dual lifting can be applied for many heavier and wider blocks and modules to shorten the construction time of ships and off-shore platforms.

Enhancement of Saccharification Yield of Ulva pertusa Kjellman by High Pressure Homogenization Process for Bioethanol Production (구멍갈파래의 고압 균질 전처리 공정을 통한 바이오에탄올 생산용 당화수율 증진)

  • Choi, Woon-Yong;Lee, Choon-Geun;Ahn, Ju-Hee;Seo, Yong-Chang;Lee, Sang-Eun;Jung, Kyung-Hwan;Kang, Do-Hyung;Cho, Jeong-Sub;Choi, Geun-Pyo;Lee, Hyeon-Yong
    • KSBB Journal
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    • v.26 no.5
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    • pp.400-406
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    • 2011
  • This study was investigated to improve the saccharification yield of Ulva pertusa Kjellman by the high pressure homogenization process. It was found that the high pressure homogenization pretreatment effectively destructed the cell wall structures only by using water. The high pressure homogenization process was operated under various conditions such as 10000, 20000 or 30000 psi with different recycling numbers. The optimal condition was determined as 30000 psi and 2 pass of recycling numbers and the sugar conversion yields were 16.02 (%, w/w) of glucose and 14.70 (%,w/w) of xylose, respectively. In the case of enzymatic treating the hydrolyzates with 5 FPU/glucan of celullase and 100 units/mL of amyloglucosidase, 65.8% of carbohydrates was converted into glucose. Using the hydrolysates of Ulva pertusa Kjellman, 48.7% of ethanol was obtained in the culture S.cerevisiae. These results showed that the high pressure homogenization process could efficiently hydrolyze the marine resource by using only water for bioethanol production.

A Study on Maritime-Specialized Development of Busan International Finance Center (부산국제금융센터 해양특성화 개발방안 연구)

  • Cho, Jae-Ho;Lee, Han-Seok
    • Journal of Navigation and Port Research
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    • v.35 no.5
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    • pp.445-454
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    • 2011
  • According to financial hub related law of government, new financial hub in Busan will be differentiated from existing other financial hubs by reflecting regional characteristics as financial cluster and by connecting with business hub. Based on an ongoing busan international finance center in Munhyun innovation city. this study is focused on suggesting development methodes for international competitiveness of Busan international finance center considering of maritime-specialization connecting with citizen park and busan north port renewal districts. through the financial hub concept, types, be valid conditons, competitiveness and international case studies over the analysis of development conditions and a development plans for developing fosterage-programs suppementary and strategy, guidelines of physical developmentde direction.

Preparation of Corncob Grits as a Carrier for Immobilizing Yeast Cells for Ethanol Production

  • Lee, Sang-Eun;Lee, Choon Geun;Kang, Do Hyung;Lee, Hyeon-Yong;Jung, Kyung-Hwan
    • Journal of Microbiology and Biotechnology
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    • v.22 no.12
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    • pp.1673-1680
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    • 2012
  • In this study, DEAE-corncobs [delignified corncob grits derivatized with 2-(diethylamino)ethyl chloride hydrochloride ($DEAE{\cdot}HCl$)] were prepared as a carrier to immobilize yeast (Saccharomyces cerevisiae) for ethanol production. The immobilized yeast cell reactor produced ethanol under optimized $DEAE{\cdot}HCl$ derivatization and adsorption conditions between yeast cells and the DEAE-corncobs. When delignified corncob grit (3.0 g) was derivatized with 0.5M $DEAE{\cdot}HCl$, the yeast cell suspension ($OD_{600}$ = 3.0) was adsorbed at >90% of the initial cell $OD_{600}$. This amount of adsorbed yeast cells was estimated to be 5.36 mg-dry cells/g-DEAE corncobs. The $Q_{max}$ (the maximum cell adsorption by the carrier) of the DEAE-corncobs was estimated to be 25.1 (mg/g), based on a Languir model biosorption isotherm experiment. When we conducted a batch culture with medium recycling using the immobilized yeast cells, the yeast cells on DEAE-corncobs produced ethanol gradually, according to glucose consumption, without cells detaching from the DEAE-corncobs. We observed under electron microscopy that the yeast cells grew on the surface and in the holes of the DEAE-corncobs. In a future study, DEAE-corncobs and the immobilized yeast cell reactor system will contribute to bioethanol production from biomass hydrolysates.