• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권2호
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• pp.141-146
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• 1999

The eigenvalue equations of multiple waveguides with step-index profile are derived by using the WKB theory. Phase changes unique to step-index discontinuity areintroduced when applying the WKB connection formula to turning points. The transfer matrix method is employed for the analysis of multiple structure and the derived eigenvalue equation are represented in the recursive form. The results by the WKB are compared with those by the FEM for a three-waveguide coupler.

• Journal of Korean Neurosurgical Society
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• 제50권3호
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• pp.248-251
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• 2011

Intracranial pial arteriovenous fistulas (AVFs) are rare vascular lesions of the brain. These lesions consist of one or more arterial connection to a single venous channel without true intervening nidus. A 24-year-old woman visited to our hospital because of headache, vomiting, dizziness and memory disturbance that persisted for three days. She complained several times of drop attack because of sudden weakness on both leg. Cerebral angiograms demonstrated a giant venous aneurysm on right frontal lobe beyond the genu of corpus callosum, multiple varices on both frontal lobes fed by azygos anterior cerebral artery, and markedly dilated draining vein into superior sagittal sinus, suggesting single channel pial AVF with multiple varices. Transarterial coil embolization of giant aneurysm and fistulous portion resulted in complete disappearance of pial AVF without complication.

• Ocean Systems Engineering
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• 제8권2호
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• pp.201-221
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• 2018

In this paper a comprehensive study for the structural control of Jacket platform with Magneto-Rheological (MR) damper is presented. The control is implemented as a closed loop feedback of the applied voltage in the MR Damper using fuzzy logic. Nine cases of combinations with MR damper are presented to complete the work. The selection of the MR damper (RD 1005-3) is based on the operating parameters (i.e., the range of frequency and displacement). Bingham model is used to obtain the control forces. The damping co-efficient of the model is obtained using empirical relationship between the voltage in the MR damper and input velocity from the structural members. The force acting on the structure is obtained from Morison equation using P-M spectrum. The results show that the reliable control was obtained when there was a continuous connection of multiple MR dampers with the lower levels of the structure. Independent MR dampers at different levels provided control within a range, while the MR dampers placed at alternate positions gave very high control.

• 한국통신학회논문지
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• 제25권3B호
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• pp.399-407
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• 2000

Recently, supporting ATM networks under LINUX operating systems environment has been actively studied. An ATMARP server in a conventional LINUX environment was designed under the ATMARP single-server to operate independently within a Local IP Subnet(LIS). In this paper, an ATMARP multi-server is introduced and implemented an ATMARP-server managing multiple LIS's on the LINUX-based IPOA. The ATMARP protocol processing functions and addition/deletion functions on management tables are required to implement the ATMARP multi-server. These functions can solve the problem of increasing the number of ATMARP servers in ATMARP single-server environment. The file transmission experiment with a connection configuration between LIS's shows that multiple LIS' con be managed by an ATMARP-server. As the results, the ATMARP multi-server scheme yields a smaller number of servers than that of the conventional ATMARP single-server scheme, and the network composition can be improved substantially.

• 제어로봇시스템학회논문지
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• 제11권2호
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• pp.144-151
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• 2005

We propose an optimization method to reduce the assembly time of chip mounters. Feeder arrangement and assembly sequence are determined considering the multiple feeder assignment. The problem is divided into two sub-problems: feeder arrangement problem and assembly sequence problem. We present mathematical model for each sub-problem. The clustering algorithm and assignment algorithm are applied to solve the feeder arrangement problem. The assignment algorithm and connection algorithm are applied to solve the assembly sequence problem. Simulation results are then presented to verity the usefulness of the proposed method.

• 소성∙가공
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• 제14권9호통권81호
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• pp.756-763
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• 2005

The applicability and productivity of hydroforming process can be increased by combining pre- and post-forming processes such as the bending, piercing and embedding process. For the fabrication of automotive parts, the hollow bodies with connecting nuts are widely used to connect parts together. Hollow body with connecting nuts has been conventionally fabricated by welding nuts or screwing in autobody screws. It requires multiple steps and devices fur the welding and/or screwing Therefore in this study, hydro-embedding process that combines the hydraulic embedding of connecting element(nut) with hydroforming process is investigated. Studies on the hydro-embedding technology have been performed to optimize the shape of the connecting element by analyzing the deformed mode of the embedded tube The effects of the shape of the screw tip, screw thread and shape of thread on the connection force between the tube and the connecting element have been investigated to optimize the shape of connecting element. Finite element analysis has also been performed to provide deformation behaviors of the tube surrounding a hole produced by hydro-embedding.

• Journal of the Korean Wood Science and Technology
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• 제28권4호
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• pp.72-82
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• 2000

Attempts were made to analyze the behavior of single and multiple-bolted connections through theoretical methods such as European yield theory, empirical approaching method, and semi-rigid theory instead of many experimental methods that have been actually inefficient and non-economical. In the case of a single-bolted connection, if accurate characteristic values of a material could be guaranteed, it would be more convenient and economical to perform the behavior analysis using a model based on the semi-rigid theory, instead of the existing complex yield model, or the empirical formula which produces errors, giving different results from the actual ones. If the variables of equation determining the load and deformation could be appropriately controlled, the analytical method in conjunction with a semi-rigid theory could be effectively applied to obtain the desirably predicted value, considering that the appropriate solution could be derived through a simpler equation using a less difficult method compared to the existing yield model. It is concluded that analytical method with semi-rigid theory can be used in the behavior analysis of bolted connection because our developed method showed excellent analysis ability of behavior until number of bolt is two. Although our analytical method has the disadvantage that the number of bolt is limited to two, it is concluded that it has the advantage than numerical method which complicated and time-consuming.

• 대한토목학회논문집
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• 제32권5D호
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• pp.519-525
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• 2012

본 연구에서는 역세권개발의 핵심요소로서 3가지를 제시하였다. 우선 역의 입지에 따른 주변토지이용, 철도노선 개수에 따른 역사유형, 역사개발방식을 고려한 역세권개발 유형을 제시하는 것이다. 다음은 역세권 개발이 성공하려면 역의 기능이 제대로 발휘되어야 한다. 이를 위해 역으로의 접근성을 판단하는 적정수준의 연계체계 구축방안을 제시하였다. 마지막으로 역으로의 접근 후 승객이 편리하게 환승할 수 있도록 하는 승하차 시설을 배치기준을 제시하였다.

• 통합자연과학논문집
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• 제11권4호
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• pp.192-196
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• 2018

The mobile agent paradigm can be exploited in a variety of ways, ranging from low-level system administration tasks to middle ware to user-level applications. Mobile agents can be useful in building middle-ware services such as active mail systems, distributed collaboration systems, etc. An active mail message is a program that interacts with its recipient using a multimedia interface, and adapts the interaction session based on the recipient's responses. The mobile agent paradigm is well suitable to this type of application, since it can carry a sender-defined session protocol along with the multimedia message. Mobile agent communication is possible via method invocation on virtual references. Agents can make synchronous, one-way, or future-reply type invocations. Multicasting is possible, since agents can be aggregated hierarchically into groups. A simple check-pointing facility has also been implemented. Another proposed solution is to use multi agent computer systems to access, filter, evaluate, and integrate this information. We will present the overall architectural framework, our agent design commitments, and agent architecture to enable the above characteristics. Besides, the each information needed a mobile agent system such as text, graphic, image, audio and video etc, constructed a great capacity multimedia database system. However, they have problems in establishing connections over multiple subnetworks, such as no end-to-end connections, transmission delay due to ATM address resolution, no QoS protocols. We propose a new connection management scheme in the thesis to improve the connection management involved of mobile agent systems.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 2부
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• pp.115-120
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• 2008

본 논문은 하나의 미디어아트 작품에 대한 분석과 구현된 기술을 제공한다 3차원 그래픽 기술을 이용하여 다중 동영상 플레이어를 구현하였으며, 모든 동영상은 상호 연동되어 동작한다 컴퓨터의 소프트웨어로 구현된 동영상 플레이어에 관객이 참여하여 관객 스스로 감성적 자극을 얻을 수 있도록 구상하였다. 각 플레이어에 인간의 희로애락을 표현하며 특정화면에 대한 경험의 공감을 표현한다. 시스템의 성능에 따라 N2개 플레이어가 증가될 수 있으며, 더욱 많은 동영상간의 복합적인 연계를 통해 예술적 메시지를 전달할 수 있을 것으로 생각한다.