• 해양환경안전학회지
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• 제24권3호
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• pp.367-372
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• 2018

The objective of this paper is to optimize the cross-section of aluminum decking units used in the bass boats under operating conditions, and to verify the optimized model from the results via by ANSYS software. Aluminum decking unit is needed to endure specific loading while leisure activity and sailing. For a stiffer and more cost-neutral aluminum decking unit, optimization is often considered in the naval and marine industries. This optimization of the aluminum decking unit is performed using the ANSYS program, which is based on the topology optimization method. The generation of finite element models and stress evaluations are conducted using the ANSYS Multiphysics module, which is based on the Finite Element Method (FEM). Through such a series of studies, it was possible to determine the most suitable case for satisfying the structural strength found among the phase-optimized aluminum deck units in bass boats. From these optimization results, CASE 1 shows the best solution in comparison with the other cases for this optimization. By linking the topology optimization with the structural strength analysis, the optimal solution can be found in a relatively short amount of time, and these procedures are expected to be applicable to many fields of engineering.

• Steel and Composite Structures
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• 제18권4호
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• pp.811-831
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• 2015

This paper focuses on the strengthening methods used for improving the compression behaviors of perforated box-section walls as provided in the anchorage zones of steel pylons. Rectangular plates containing double-row continuous elliptical holes are investigated by employing the boundary condition of simple supporting on four edges in the out-of-plane direction of plate. Two types of strengthening stiffeners, named flat stiffener (FS) and longitudinal stiffener (LS), are considered. Uniaxial compression tests are first conducted for 18 specimens, of which 5 are unstrengthened plates and 13 are strengthened plates. The mechanical behaviors such as stress concentration, out-of-plane deformation, failure pattern, and elasto-plastic ultimate strength are experimentally investigated. Finite element (FE) models are also developed to predict the ultimate strengths of plates with various dimensions. The results of FE analysis are validated by test data. The influences of non-dimensional parameters including plate aspect ratio, hole spacing, hole width, stiffener slenderness ratio, as well as stiffener thickness on the ultimate strengths are illustrated on the basis of numerous parametric studies. Comparison of strengthening efficiency shows that the continuous longitudinal stiffener is the best strengthening method for such perforated plates. The simplified formulas used for estimating the compression strengths of strengthened plates are finally proposed.

• 한국해양공학회지
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• 제17권5호
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• pp.88-94
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• 2003

A series of tests of 5 model ships, selected from a data survey of 10 Gross Tonnage actual fishing boats, were performed in two circulating water channels (Chosun University in Korea and WJFEL in Japan), in order to develop the basic hull form of a 25 knots-class fishing boat. Resistance tests, trim and sinkage measurements and wave pattern observations etc., were included in each I1wdel test, and the model test results were compared and analyzed. The result was as follows: P-4 hull form ship changed into Deep V type bow is the best hull form with good performance, especially with regard to ship's resistance efficiency.

• 한국강구조학회 논문집
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• 제10권4호통권37호
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• pp.801-811
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• 1998

본 논문은 풍동실험을 통하여 ${\pi}$형단면을 가지는 강합성사장교의 공기역학적 특성과 제진방법에 대한 연구이다. 제진장치로는 Fairing, Extension, Post, Flap 등이 사용되었고, 가장 효과적인 개선단면을 선정하여 영각, 감쇠비와 난류실험을 수행하여 내풍안정성을 평가하였다. 실험결과 선정된 개선단면에서 공기역학적 내풍안정성이 향상되었고 공기역학적특성이 규명되었다. 따라서 본 연구에서 수행된 ${\pi}$형단면은 내풍설계의 기초 자료로 활용될 수 있을 것이다.

• 한국임상수의학회지
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• 제33권3호
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• pp.176-178
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• 2016

Here we report a case of a 7-month-old Jindo puppy with a double intussusception. On survey radiography, a soft tissue opacity mass was identified in the mid-abdomen. Abdominal ultrasonography revealed a triple-circle sign. Double intussusception was diagnosed based on these findings. Exploratory laparotomy confirmed it to be a double intussusception in the small intestine. Small intestine involving the double intussusception was surgically resected followed by anastomosis. The dog had good prognosis without any complication. To the best of our knowledge, double intussusception is an extremely rare form of intestinal disease in dogs. It may cause blood supply to that section to be greatly reduced, thus causing ischemia and necrosis of the bowel tissue. Timely diagnosis with ultrasonographic findings and immediate surgical intervention are important to improve the prognosis of such cases.

• Journal of Biosystems Engineering
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• 제31권6호
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• pp.474-481
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• 2006

In this paper, a new type blow head was developed and pneumatic application system was evaluated. The blow head had one operating factor, inserting length of collecting plate, that was directly related to discharge rate and application pattern. To determine Proper blow head arrangement and application height, a blow head set was tested. Three-way ANOVA was conducted to investigate relationships between CV value, the discharge rate and inserting length of collecting plate. The discharge rate and inserting length of collecting plate were statistically significant at p=0.01, affecting uniformity of application pattern. The best CV value among the application tests was 23.3% when the application rate and application height was 23.5 g/sec and 80 cm respectively. The worst CV value was 63.3% in 111.4 g/sec. Therefore, it is necessary to increase number of blow head in a section of the boom in improve application uniformity.

• 한국항행학회논문지
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• 제18권5호
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• pp.455-460
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• 2014

장거리 광전송 시스템에서 그룹 속도 분산과 비선형 현상에 의한 왜곡을 보상할 수 있는 분산 제어 (DM; dispersion management)와 광 위상 공액 기술이 결합된 전송 링크의 최적 설계를 위한 성능 분석을 수행하였다. 즉 전체 전송 링크의 중간에 위치한 광위상 공액기 (OPC; optical phase conjugator) 양쪽의 전송 구획에서의 잉여 분산의 상호 관계가 최적 전체 잉여 분산 (NRD; net residual dispersion)에 미치는 영향을 살펴보았다. 시뮬레이션 결과 전반 전송 구획에서의 잉여 분산과 후반 전송 구획에서의 잉여 분산의 차이를 10 ps/nm로 하여 전체 전송 링크의 NRD를 10 ps/nm로 설정하여야 가장 우수한 보상이 이루어진다는 것을 확인하였다.

• 융복합기술연구소 논문집
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• 제5권2호
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• pp.27-32
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• 2015

Air intakes are an essential component of aircraft engines. They are mainly used to offer uniform airflows to engine faces. Fighter aircraft have to mask the engine face inside the fuselage in order to reduce the Radar Cross Section(RCS). Therefore, offset intakes like a S-Duct are one of promising components for this purpose. During a fight, it is unavoidable that the flow will enter the intakes at some face angles other than zero. In this case, the performance of the aircraft engine will be influenced to the angle of incidence. In this study, the CFD analysis of the semi-circular S-Duct with AR(0.5,0) is performed to investigate the influence of the angle of incidence on the performance of the S-Duct using a distortion coefficient. To consider the adverse pressure gradient, a $k-{\omega}$ SST turbulence model is employed. The secondary flow and flow separation are observed for all computational cases. It is found that the positive incidence angle produces the best performances.

• 한국실내디자인학회논문집
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• 제14호
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• pp.107-113
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• 1998

This stud tires to present a general picture about Alessandro Mendini's unique idea of redesign. One of Italian post-war redical architect and designer mendini gives us a special opportunity to appreciate the social cultural and political context where the post-war Italian design lies. Also known as "banal design" Mendin's design revolutionized the way in which we practice utilize and think about design itself. It is my opinion that the idea of his redesign can be best understood when we consider the social contest of Italian design. Unlike that of other European countries post-war Italian design gave special emphasis on how design can or should be more than a simple activity of making aesthetic or industrial products. In terms of these possibilities Mendini was never optimistic : today we are completely controlled by dehumanized mass production and it is impossible for design to take a special role for a social change Then Mendini's pessimism is bound up with the spirit of this age widely known as postmodernism. Even though Mendini himself never characterized his design as postmodern it is not difficult to identify various postmodern elements in his idea and practice of redesign. Thus in the final section of this study I shall investigate the postmodern elements in this design and furthermore such an idea as what makes Mendini postmodern.

• 무역상무연구
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• 제30권
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• pp.59-88
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• 2006

After sources of risks are identical and measured, a decision can be made as to how the risk should be handled. A pure risk that is not identical does not disappear ; the business merely loses the opportunity to consciously decide on the best technique for dealing with that risk. The process used to systematically manage risk exposures is known as risk management. Risk management is the logical process used by business firms and individuals to deal with their exposures to loss. It is a strategy of preloss planning for postloss resources. Besides, in the enterprise judiciary researches the textbook and the instance which relate risks, and reflects it to the written contract provision and various every manuel or holds seminar. It is a risk management which this talks generally. Here it stands but it becomes a problem the quality of type and countermeasure of risks. The purpose of this paper aims to explain adequate preventions to positively predict the risk this before being materialized, in practical section which is directly exposed to these risks in introducing international sale contracts(for example, the FOB and CIF contract) and the active management method of the risk which accompanys to the execution. And also analyzes the Lite-On case which relates with an international sale contracts.