• 센서학회지
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• 제16권4호
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• pp.319-323
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• 2007

This paper describes the mechanical characteristics of poly 3C-SiC thin films grown on Si wafers with thermal oxide. In this work, the poly 3C-SiC thin film was deposited by APCVD method using only Ar carrier gas and single precursor HMDS at $1100^{\circ}C$. The elastic modulus and hardness of poly 3C-SiC thin films were measured using nanoindentation. Also, the roughness of surface was investigated by AFM. The resulting values of elastic modulus E, hardness H and the roughness of the poly 3C-SiC film are 305 GPa, 26 GPa and 49.35 nm respectively. The mechanical properties of the grown poly 3C-SiC film are better than bulk Si wafers. Therefore, the poly 3C-SiC thin film is suitable for abrasion, high frequency and MEMS applications.

• 대한조선학회지
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• 제20권1호
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• pp.29-33
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• 1983

The loading condition, of a ship, especially a multi-purpose cargo carrier, in service, is often changed. Then, the prediction of natural frequency changes is necessary to provide measures for prevention of ship vibrations. In this paper a simplified method for the above purpose is presented. The bases of the method are analytical solutions for the lateral vibrations of uniform Timoshenko beams carrying a concentrated mass and the Dunkerley's formula. In this method a ship in the standard ballast condition is reduced to a uniform Timoshenko beam having same system parameters as those of the midship section. To investigate the validity of the proposed method, numerical calculations are carried out for a 46,000 DWT bulk carrier and compared with detailed calculations based on the finite difference method. Even in cases those the cargoes in a hold, length of which is about 13% of the ship's length, are reduced to a concentrated mass, the proposed method gives results of several percent differences from the detailed calculations up to the six-noded mode.

• 대한조선학회 특별논문집
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• 대한조선학회 2015년도 특별논문집
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• pp.41-45
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• 2015

In this study reviewed the validity of the estimated optimum trim by the numerical analysis. For this purpose, the numerical analysis of the trim optimization for 6500TEU container carrier and capesize bulk carrier were carried out using Star-CCM+, which results were compared with the results of model tests. The reliability of results of the numerical analysis was confirmed via comparing the resistance determined by the numerical analysis and model test. The performance of self-propulsion at each trim conditions were estimated using the calculated resistance by numerical analysis. The BHP at each trim condition were calculated by estimated performance of self-propulsion, which trend of results were confirmed similar trend of result of model test.

• 한국기계연구소 소보
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• 통권9호
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• pp.183-191
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• 1982

This report describes the analysis method of the full-scale propulsive performance by using the data of model test and the full-scale speed trial. The model test data were analyzed by the computer program "PPTT" based on "1978 ITTC Performance Prediction Method for Single Screw Ships." Also the full-scale speed trial data were analyzed by the computer program "SSTT" based on the newly proposed “SRS-KIMM Standard Method of Speed Trial Analysis." An analysis of model and full-scale test data was carried out for a 60.000 DWT Bulk Carrier and the correlation between model and full-scale ship was stuied.

• 전자공학회논문지A
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• 제30A권7호
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• pp.38-46
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• 1993

Based on the close correlation between the optoelectronic and electrical characteristics of laser diodes, this paper is to present an exact model for electrical characteristics of laser diodes with bulk active layers so that the optoelectronic characteristics may be estimated from the electrical Characteristics. Among the considered models, the most exact model is shown to be one which uses the Fermi-Dirac integral and the bimolecular recombination and takes into account the energy-gap shrinkage with the injected carrier density.

• 대한조선학회지
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• 제41권2호
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• pp.4-24
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• 2004

우리나라 조선해양산업은 1970년대 초에 본격적으로 세계 조선시장에 진출하여 짧은 기간에 세계 1위의 조선대국으로 도약하였다. 현재의 위상을 공고히 하고 지속적인 경쟁력 우위를 유지하기 위해서는 기존 주력제품의 원가 및 품질의 차별화 전략과 아울러 고부가 제품의 수주확대가 무엇보다 필요할 것이다. 현재 우리의 주력판매 선종인 유조선(Tanker), 산적화물선(Bulk Carrier), 6,000TEU급 미만의 일반컨테이너선 등은 이미 성숙기에 진입한 제품으로서, 기업주도로 원가절감 및 품질향상이 활발히 추진하고 있으나 조선업의 미래 성장동력으로서는 한계가 있다. (중략)

• 대한조선학회지
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• 제25권3호
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• pp.35-45
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• 1988

This paper presents a sophisticated Sequential Linear Approximation Method(SLAM) to solve nonlinear optimization problem and the performance of this method is compared with those of the Penalty Function Method(SUMT), Tangent Search Method(TSM) and Flexible Tolerance Method(FTM). To improve the convenience and flexibility in using the proposed SLAM, an user oriented design optimization language is developed and the application examples are shown for the optimization of propeller principal dimensions and the optimization of bulk carrier principal particulars.

• 무역상무연구
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• 제12권
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• pp.377-401
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• 1999

This study is focused on the privity of the contract of carriage of goods by sea, so to speak, privity between B/L holder and carrier by transfer of bill of lading, privity by attornment to delivery order and conflict between bills of lading and charterparty terms. Under a CIF contract, possession of the bill of lading is equivalent to possession of the goods, and delivery of the bill of lading to the buyer or to a third party may be effective to pass the property in the goods to such person. The bill of lading is a document of title enabling the holder to obtain credit from banks before the arrival of the goods, for the transfer of the bill of lading can operate as a pledge of the goods themselves. In addition, it is by virtue of the bill of lading that the buyer or his assignee can obtain redress against the carrier for any breach of its terms and of the contract of carriage that it evidences. In other words the bill of lading creates a privity between its holder and the carrier as if the contract was made between them. The use of delivery orders in overseas sales is commen where bulk cargoes are split into more parcels than there are bills of lading, and this practice gives rise to considerable difficulties. For example, where the holder of a bill of lading transferred one of the delivery orders to the buyer who presented it to the carrier and paid the freight of the goods to which the order related, it was held that there was a contract between the buyer and the carrier under which the carrier could be made liable in repect of damage to the goods. The contract was on the same terms as that evidenced by, or contained in, the bill of lading, which was expressly incorporated by reference in the delivery order. If the transferee of the delivery order presents it and claims the goods, he may also be taken to have offered to enter into an implied contract incorporating some of the terms of the contract of carriage ; and he will, on the carrier's acceptance of that offer, not only acquire rights, but also incur liabilities under that contract. Where the terms of the charterparties conflict with those of the bills of lading, it is interpreted as below. First, goods may be shipped in a ship chartered by the shipper directly from the shipowner. In that case any bill of lading issued by the shipowner operates, as between shipowner and charterer, as a mere receipt. But if the bill of lading has been indorsed to a third party, between that third party and carrier, the bill of lading will normally be the contract of carriage. Secondly, goods may be shipped by a seller on a ship chartered by the buyer for taking delivery of the goods under the contract of sale. If the seller takes a bill of lading in his own name and to his own order, the terms of that bill of lading would govern the contractual relations between seller and carrier. Thirdly, a ship may be chartered by her owner to a charterer and then subchartered by the chaterer to a shipper, to whom a bill of lading may later be issued by the shipowner. In such a case, the bill of lading is regarded as evidencing a contract of carriage between the shipowner and cargo-owners.

• 수산해양교육연구
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• 제29권3호
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• pp.665-676
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• 2017

Over the past several years, sea trade have increased traffic by ships which highlighted a problem of unwanted species invading the surrounding seas through ship's ballast water discharge. Maritime trade volume has continuously increased worldwide and the problem still exists. The respective countries are spending billions of dollars in an effort to clean up the contamination and prevent pollution. As part of an effort to solve marine environmental problem, BWM(Ballast Water Management) convention was adopted at a diplomatic conference on Feb. 13 2004. In order to comply harmoniously this convention by each country. This convention will be effective after 12 months from the date which 30 countries ratified accounting for more than 35% of the world merchant shipping volume. On Sep. 8 2016, Finland ratified this convention and effective condition was satisfied as 52 states and world merchant vessel fleet 35.1441%. Thus, after Sep. 8 2017, all existing vessels shall be equipped with BWTS(Ballast Water Treatment System) in accordance with D-2 Regulation, which physically handles ballast water from ballast water exchange system(D-1 Regulation). In this study, we analyzed in detail the optimal design method using the Risk Analysis and Evaluation technique which is mainly used in the manufacturing factory or the risky work site comparing with the traditional design concept method applying various criteria. The Risk Assessment Method is a series of processes for finding the Risk Factors in the design process, analyzing a probility of the accident and size of the accident and then quantifying the Risk Incidence and finally taking measures. In this study, this method was carried out for Electrolysis treatment type on DWT 180K Bulk Carrier using "HAZOP Study" method among various methods. In the Electrolysis type, 63 hazardous elements were identified.

• 대한전자공학회논문지SD
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• 제46권12호
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• pp.24-29
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• 2009

$0.18{\mu}m$ deep n-well 벌크 NMOSFET에서 측정된 차단주파수 $f_T$의 고온종속성을 모델화하기 위해, 측정된 S-파라미터를 사용한 정확한 RF 방법으로 $30^{\circ}C$에서 $250^{\circ}C$까지 전자속도 고온 데이터가 추출되었다. 이러한 추출데이터를 사용하여 개선된 온도종속 전자속도 방정식이 높은 온도의 범위에서 생기는 기존 방정식의 모델링 오차를 없애기 위해 개발되었으며 BSIM3v3 SPICE RF 모델에 구현되었다. 개선된 온도 종속 방정식은 기존 모델보다 $30^{\circ}C$에서 $250^{\circ}C$까지 측정된 $f_T$와 더 잘 일치하였으며, 이는 개선된 방정식의 정확성을 입증한다.