본 논문에서는 해저케이블 부두 하역용 장비인 코일링 암(coiling arm)에 대한 국산화 자체개발 내용 중 구조설계 및 해석 결과 내용을 제시하였다. 상세 구조설계를 위해 3차원 CAD 프로그램을 이용하여 고 정밀도의 모델링을 수행하였고, 유한요소 기법을 이용하여 전산구조해석을 수행하였다. 코일링 암의 활용 목적에 맞추어 하역대상 케이블을 선박에서 케이블 탱크로 하역시 효과적으로 가이드 할 수 있도록 베어링 및 롤러 부품을 설계하여 메인 암이 회전하고 케이블 가이드가 이동할 수 있도록 하였고, 기존의 외국 모델에서 사용하던 와이어 및 모터 시스템을 이용한 케이블 가이드 작동방식을 유압 시스템을 이용한 작동방식으로 변경하여 원가절감을 달성하면서 사용자가 직관적으로 작동할 수 있도록 설계하였다. 장비 자체의 자중 및 하역 케이블 하중조건에 대한 응력 해석을 수행하였고, 유압시스템의 과작동에 따른 파손 가능성을 고려하였다. 케이블 가이드의 운동 및 설치 지면의 경사도에 따른 전복 안전성 해석을 수행하였으며, 설치장소의 풍하중 효과도 추가로 고려하였다. 본 연구를 통해 기존 수입품 코일링 암의 작동방식 개선과 독자적인 구조설계 및 해석 방법을 확립하였으며, 실제 국내 최초로 자체 개발된 제품의 현장설치 완료 및 하역작업의 효율적이고 정상적인 운영을 완료 및 검증하였다.

This study develops an efficient numerical algorithm to predict wave-resistance performance of a catamaran hull. The developed numerical algorithm is applied to evaluate wave-resistance performance for two different twin hull forms with a asymmetric and a symmetric mono hull. Numerical calculations and model tests are compared to validate a developed numerical algorithm adopted in the current work. Comparisons are carried out through the sinkage at the bow and stern, the trim and the wave-making resistance coefficient. Model test is performed in order to verify the numerical results. The comparative analysis study regarding hydrodynamic characteristic of different twin hull forms is worthy of application in the catamaran hull form development stage.

PURPOSES: Design of approach roads of rest areas in highway has many drawbacks such as geometric design elements. There has been traffic accidents occured in these approach roads of rest areas. Thus, design criteria is required in order to protect accidents from being occurred. In case of Korea, geometric structure design criteria of entry facilities, such as toll-gate, interchange, junction etc was established. However there are no presence in a detailed standards for geometric structure of the rest area which affiliated road facilities. METHODS: In this study, analytic on accidents was carried out in regards to the entry of geometric structure of resting areas by utilizing a sight survey and an investigation research of traffic accidents. The survey was targeting 135 general service areas. Collisions with physical channelization and safety facilities occurred due to speeding, rapid entry, and etc at the entrance nose section. At the entrance connector roads, accidents caused by speeding, negligence, over-operation of handle of drivers were main reason of accidents. Discriminant analysis were conducted about geometric elements to distinguish influencing factors for traffic accidents. the lengths and access angles of the entrance connector roads were regarded as to have the high relation with traffic accidents. RESULTS: After classifying the design section of resting areas' entry as well as derive design elements on each section, a speed measurement by targeting entry of rest areas and car behavior surveys were performed, then each element's minimum standard was derived through the analyses. According to the speeds at the starting/end point of entrance connector road, the range of the junction setting angle of the entrance connector road is defined as 12˚~17˚ and the connector length model was suggested. CONCLUSIONS: Suggest improvement plans for existing rest areas that can be applied realistically. This should be corresponded to the standards of entry and exit of developed rest areas.

PURPOSES: Road Design Consistency Evaluation can guarantee road alignments with safety factors, however it can be hard work to deal with general car accident factors in only this evaluation index. Ideal Road Design Consistency Evaluation is show the mutual balance of road alignment and human factors with a variety of factors for road safety. METHODS: This study carried out overall road safety evaluations which are methods of running speeding consistency and car platoon safety analysis (driver's behaviors factors) as well. RESULTS: Out of 13 sections in a experimental road layout, safety factors of 8 sections showed 'Good' or 'Fair' status. However, 'Poor' results were found out in 5 sections. Particularly, it showed the different outcomes among the 4 evaluation methods used in this study. CONCLUSIONS: Road safety countermeasures were proposed for the potentially dangerous sections in road which failed to identify in the other methods. This study will contribute toward future study of more reliable Road Design Consistency Evaluation in the future for road safety.

PURPOSES: This study is to analyze different vehicle load effects for a bridge design of South and North Korea in order to prepare a common design specification and to secure the safety of transportation when the highway bridges of South and North Korea use together. METHODS: Based on the literature review, this study considers vehicle load effects by comparing different characteristics of the standard vehicle and other differences of the bridge design specification between South and North Korea. And structural modeling of three-span continuous PSC Beam Bridge are analyzed and the bridge capacity according different vehicle loads of South and North Korea is evaluated. RESULTS: The result of this study indicates that the bridge capacity and the design vehicle weight of North Korea are smaller than the bridge capacity and the design vehicle weight of South Korea. Also this study demonstrates that the design vehicle array and other characteristics of North Korea are very different than the design vehicle array and other characteristics of South Korea. CONCLUSIONS: It is expected that the outcomes of this study can be useful in the set-up of South-North Bridge Specification because similar previous studies are rarely found.

In this study, a theoretical investigation of optimized sleeper spacing which can suppress resonances of a railway track is attempted. To achieve this, we introduced a minimization problem in which the objective function is given by the wave transmittance and the design variable is defined by sleeper distribution. In the analysis the rail is modeled by a Timoshenko beam and the sleeper is represented by a mass. The infinite track analysis is realized by attaching the transmitting boundaries at both ends of the finite optimization region. Through numerical analyses the sleeper spacing effective in reduction of the transmittance is discussed. Furthermore, the feasibility of the proposed method is validated in the aspect of vibration reduction through response analyses for a harmonic load.

A level set based topological shape optimization method for nonlinear structure considering hyper-elastic problems is developed. To relieve significant convergence difficulty in topology optimization of nonlinear structure due to inaccurate tangent stiffness which comes from material penalization of whole domain, explicit boundary for exact tangent stiffness is used by taking advantage of level set function for arbitrary boundary shape. For given arbitrary boundary which is represented by level set function, a Delaunay triangulation scheme is used for current structure discretization instead of using implicit fixed grid. The required velocity field in the actual domain to update the level set equation is determined from the descent direction of Lagrangian derived from optimality conditions. The velocity field outside the actual domain is determined through a velocity extension scheme based on the method suggested by Adalsteinsson and Sethian(1999). The topological derivatives are incorporated into the level set based framework to enable to create holes whenever and wherever necessary during the optimization.

A topology optimization method for phononic crystals is developed for the design of sound barriers, using the level set approach. Given a frequency and an incident wave to the phononic crystals, an optimal shape of periodic inclusions is found by minimizing the norm of transmittance. In a sound field including scattering bodies, an acoustic wave can be refracted on the obstacle boundaries, which enables to control acoustic performance by taking the shape of inclusions as the design variables. In this research, we consider a layered structure which is composed of inclusions arranged periodically in horizontal direction while finite inclusions are distributed in vertical direction. Due to the periodicity of inclusions, a unit cell can be considered to analyze the wave propagation together with proper boundary conditions which are imposed on the left and right edges of the unit cell using the Bloch theorem. The boundary conditions for the lower and the upper boundaries of unit cell are described by impedance matrices, which represent the transmission of waves between the layered structure and the semi-infinite external media. A level set method is employed to describe the topology and the shape of inclusions. In the level set method, the initial domain is kept fixed and its boundary is represented by an implicit moving boundary embedded in the level set function, which facilitates to handle complicated topological shape changes. Through several numerical examples, the applicability of the proposed method is demonstrated.

Finite element analysis is to approximate a geometry model developed in computer-aided design(CAD) to a finite element model, thus the conventional shape design sensitivity analysis and optimization using the finite element method have some difficulties in the parameterization of geometry. However, isogeometric analysis is to build a geometry model and directly use the functions describing the geometry in analysis. Therefore, the geometric properties can be embedded in the NURBS basis functions and control points so that it has potential capability to overcome the aforementioned difficulties. In this study, the isogeometric structural analysis and shape design sensitivity analysis in the generalized curvilinear coordinate(GCC) systems are discussed for the curved geometry. Representing the higher order geometric information, such as normal, tangent and curvature, yields the isogeometric approach to be the best way for generating exact GCC systems from a given CAD geometry. The developed GCC isogeometric structural analysis and shape design sensitivity analysis are verified to show better accuracy and faster convergency by comparing with the results obtained from the conventional isogeometric method.

Geometric configurations such as hull shape, wall thickness, stiffener layout, and type of construction materials are the key factors influencing the structural performance of pressure hulls. Traditional theoretical approach provides quick and acceptable solutions for the design of pressure hulls within specific geometric configuration and material. In this paper, alternative approaches that can be used to obtain optimal geometric shape, wall thickness, construction material configuration and stiffener layout of a pressure hull are presented. CAE(Computer Aided Engineering) based design optimization tools are utilized in order to obtain the required structural responses and optimal design parameters. Optimal elliptical meridional profile is determined for a cylindrical pressure hull design using metamodel-based optimization technique implemented in a fully-integrated parametric modeler-CAE platform in ANSYS. While the optimal composite laminate layup and the design of ring stiffener for a thin-walled pressure hull are obtained using gradient-based optimization method in OptiStruct. It is noted that the proposed alternative approaches are potentially effective for pressure hull design.

2차원적 이미지에 생동감 있는 3-D 깊이감을 구현하기 위한 노력은 입체 지각에 대한 이론적 이해 및 그에 따른 기술적 발전과 더불어 오래 동안 지속되어 왔다. 본 논문에서는 입체경을 사용한 입체시 구현 원리에 기반을 둔 대중적인 입체경들을 간략히 개괄하고, 이들 중 액티브 셔터 방식의 입체경이 사용된 시각기억 실험 사례를 소개하였다. 실험에 참가한 피험자들은 자극들의 지각된 깊이를 기억하였으며, 이에 대한 기억 정확도가 측정되었다. 기억 및 검사를 위한 항목들의 깊이감은 1) 단안, 2) 양안 그리고 3) 단안과 양안 단서가 사용된 조건으로 각기 달리 처치되어 구분되었다. 참가자들의 기억 수행은 양안단서만이 처치된 조건에서 가장 낮았던 반면, 양안단서와 단안단서가 동시에 구현되었을 때 가장 높았다. 이러한 결과는 시각기억이 깊이 정보를 저장할 때, 양안단서를 통해 구현된 정보보다 단안 단서를 통해 구현된 정보를 더 효율적으로 저장하며, 양안단서와 단안단서가 동시에 사용되었을 때 가장 효과적인 기억 수행이 가능함을 시사한다.

목적: 노안 연령층에게 성인 테의 적합성과 얼굴 형태에 적합한 안경테 설계에 필요한 자료를 제공하고 자 하였다. 방법: 안와 질환과 안 외상이 없는 40세 이상의 얼굴 정면 촬영자 총 680명(남자 244명, 여자 436명), 얼굴 정면 촬영자 중 얼굴 측면 촬영자 총 131명(남자 60명, 여자 71명)을 대상으로 안경테 설계에 필요한 자료를 계측하고 한국 성인의 데이터와 비교하여 노안 연령층의 얼굴 형태에 적합한 안경테 설계에 필요한 자료를 분석하였다. 결과: 안경테 설계에 필요한 얼굴 형태 계측값과 안경테 설계에 필요한 계산값은 한국 성인과 비교하여 유의한 차이를 보이는 것으로 나타났다. 결론: 한국 노안 연령층과 성인의 테 설계기준은 유의한 차이를 보였으며, 본 연구 결과를 근거로 한국 노안 연령층의 안경테 기준이 새롭게 마련되어야 할 것으로 사료된다.

공정제어시스템과 같은 복잡한 시스템을 감시하고 제어하기 위한 정보 디스플레이를 설계하기 위해 두 가지의 세부적인 설계문제를 효과적으로 다루어야 한다. 정보디스플레이에서 표현할 정보의 내용을 파악하고 조직화하는 문제와 그 표현할 정보를 시각적으로 잘 표현하는 문제로 구분이 된다. Ecological Interface Design (EID)는 두 문제를 다루기 위한 이론적 배경지식과 방법을 제공하는 정보디스플레이 설계의 틀이다. EID는 1990년대 초반에

It has been recognized as an important issue to design optimally a firm's logistics network for minimizing logistics cost and maximizing customer service. It is, however, not easy to get an optimal solution by analyzing trade-off of cost factors, dynamic and interdependent characteristics in the logistics network decision making. Although there has been some developments in a system which helps decision making for logistics analysis, it is true that there is no system for enterprise-wise's on-site support and methodical logistics decision. Specially, E-biz process along with information technology has been made dramatic advance in a various industries, there has been much need for practical education closely resembles on-site work. The software developed by this study materializes efficient algorithm suggested by recent studies in key topics of logistics such as location and allocation problem, traveling salesman problem, and vehicle routing problem and transportation and distribution problem. It also supports executing a variety of experimental design and analysis in a way of the most user friendly based on Java. In the near future, we expect that it can be extended to integrated supply chain solution by adding decision making in production in addition to a decision in logistics.

The issues raised so far in the development of safety-critical systems have centered on how effectively the safety requirements are met in systems design. The systems are becoming more complex due to the increasing demand on the functionality and performance. As such, the integration of both the systems design and systems safety processes becomes more important and at the same time quite difficult to carry out. In this paper, an approach to solving the problem is presented, which is based on an integrated data model. To do so, the data generated from the inputs and outputs of the systems design and systems safety processes are analyzed first. The results of analysis are used to extract common attributes among the data, thereby making it possible to define classes. The classes then become the cores of the interface data model through which the interaction between the two processes under study can be modeled and interpreted. The approach taken has also been applied in a design case to demonstrate its value. It is expected that the results of the study could play a role of the stepping stone in extending to the architecture development of the integrated process.

본 연구에서는 화력발전소에서 온배수의 형태로 배출되는 폐열을 히트펌프의 열원으로 이용하여 온실의 난방에 활용할 수 있는 히트펌프 시스템을 설계 제작하였으며, 난방 성능을 분석하여 PE 파이프 열교환기의 설계기준을 제시하고자 하였다. PE 파이프 열교환기의 내경은 20mm, 두께는 2mm였으며, Roll의 직경은 1,000mm로 하였다. 연구결과 PE파이프 열교환기의 적정 길이는 1.0RT당 75m로 설계하는 것이 바람직할 것으로 판단되었으며, 이때 히트펌프시스템의 난방성능계수(COPh)는 3.8로 나타났다.

When manufacturing die casting mold, generally, the casting layout design should be considered based on the relation among injection system, casting condition, gate system, and cooling system. Also, the extent or the location of product defects was differentiated according to the various relations of the above conditions. In this research, in order to optimize casting design of an automobile part (Gear Box) Computer Aided Engineering (CAE) was performed by using the simulation software (ZَCast). The simulation results were analyzed and compared with experimental results. During the mold filling, internal porosities caused by air entrap were predicted and reduced remarkably by the modification of the gate system and the configuration of overflow. With the solidification analysis, internal porosities caused by the solidification shrinkage were predicted and reduced by the modification of the gate system. For making a better production dieَcasting tool, cooling systems on several thick areas are proposed in order to reduce internal porosities caused by the solidification shrinkage.

스마트폰 게임 사용자들의 급속한 증가와 모바일 사용이 급증함에 따라 개인의 인증서 사용은 필수적으로 사용하도록 하고 있다. 이 개인 인증서는 편리하면서도 개인의 정보유출 및 도용의 우려가 항상 존재하게 되어 사용자들의 불안감은 항상 함께 공존하고 있다. 이에 즈음하여 본 논문에서는 기존의 아이디와 비밀번호를 입력하던 방식을 개선하여 보다 쉬우면서도 타인이 도용하지 못하게 대응하도록 철저한 개인인증 보안 알고리즘을 적용하여 실제 스마트폰 게임 인증 사용시에 적용할 수 있도록 시뮬레이션 해 보고자 하였다. 본 논문의 수행 결과로는 안전한 스마트폰 게임 인증 서비스의 활성화와 더불어 무선 인터넷 뱅킹 서비스, 온라인 쇼핑 등 무선 인터넷을 이용한 전자 상거래의 활성화에 기여할 것으로 기대된다.