• Nuclear Engineering and Technology
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• v.55 no.9
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• pp.3140-3149
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• 2023

In theory, the sharp dose falloff at the distal end of a proton beam allows for high conformal dose to the target. However, conformity has not been fully achieved in practice, primarily due to beam range uncertainty, which is approximately 4% and varies slightly across institutions. To address this issue, we developed a new range verification system prototype: a multi-slit prompt-gamma camera (MSPGC). This system features high prompt-gamma detection sensitivity, an advanced range estimation algorithm, and a precise camera positioning system. We evaluated the range measurement precision of the prototype for single spot beams with varying energies, proton quantities, and positions, as well as for spot-scanning proton beams in a simulated SSPT treatment using a phantom. Our results demonstrated high accuracy (<0.4 mm) in range measurement for the tested beam energies and positions. Measurement precision increased significantly with the number of protons, achieving 1% precision with 5 × 10⁸ protons. For spot-scanning proton beams, the prototype ensured more than 5 × 10⁸ protons per spot with a 7 mm or larger spot aggregation, achieving 1% range measurement precision. Based on these findings, we anticipate that the clinical application of the new prototype will reduce range uncertainty (currently approximately 4%) to 1% or less.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.294-298
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• 2000

A new pulse multiplication technique based on 6-pulse thyristor converters is proposed in this paper. With the proposed technique 12-pulse 18-pulse and 24-pulse operations have been obtained both on the input current and on the output voltage. A control strategy over the whole range of phase angle is provided along with sophisticated input current and output voltage analysis. Experimental results from a laboratory prototype verify the proposed theory.

• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.577-580
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• 2003

본 논문에서는 캐릭터 디자인 프로세스의 필요성을 충족시켜주기 위해 프로토타입 이론(prototype theory)에 대한 문제점을 파악하고 이를 보완하기 위하여 전형성과 동시에 중요하게 인지되는 또 다른 속성 즉 형태 심미성의 개념적 구조를 파악하였다. 그리고 심미성을 측정 할 수 있는 척도를 검증한 선행 연구를 바탕으로 심미적 영향요소중의 하나인 비례(proportion)를 추출 하였다. 이를 적용한 새로운 캐릭터 디자인 프로세스를 구축하여 캐릭터 디자이너의 아이디어 발상의 한계성을 극복하고 소비자가 선호할 수 있는 캐릭터 디자인을 창출하여 캐릭터 디자인의 성공확률을 높이고자 하는데 연구의 목적이 있다.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.152.3-152
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• 2001

This paper describes an application of an air-pulse actuator for vibration control of a framed structure. Dynamic characteristics of the prototype actuator that utilizes an air-jet reaction force pulsated by an electromagnetic valve were investigated to use it as a control actuator. Using a control law based on the sliding mode control theory, experiments of the vibration control were carried out. The experimental results verified the validity of the actuator performance.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.749-752
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• 1999

A new interface circuit for variable resistive sensors is proposed. The interface circuit compose of only two strain gages, a voltage-to-current converter, and current mirror with two outputs. A new dual slope A/D converter based on linear operational transconductance amplifier for the testing of prototype interface circuit is also described. The theory of operation is presented and experimental results are used to verify the theoretical predictions. The results show close agreement between predicted behaviour and experimental performance.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.1226-1229
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• 2008

In this paper, we designed sandwich type pressure regulator for air pressure control system. As a result of research, we obtained several important conclusions. First, we decided theory of poppet valve and relief valve which are used in sandwich type pressure regulator, and then designed prototype of pressure regulator. Second, we organized circuit diagram of dual pressure regulator of air pressure control system.

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2000.06a
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• pp.285-291
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• 2000

필수적/수의적 논항의 이분법적 구분과 이에 따라 정문/비문을 논하는 것이 언어학과 자연어처리학에서 정설로 인정되어 왔다. 그러나 본 연구에서는 논항의 생략 현상과 왜 이러한 생략이 발생하는지에 대해 인지적인 관점에서 살펴봄으로써 기존의 이분적 개념들이 구문분석에 적합치 않음을 지적하였다. 그리고 이러한 문제점을 해결하기 위해 원형이론(prototype theory)을 도입하여 '필수적 논항도'와 '확률적 격구조'란 개념을 제안하였다. 이러한 개념들이 자연어처리의 구문분석에 효율적으로 적용될 수 있을 것으로 기대된다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.428-434
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• 2002

Almost all buildings/infrastructures made of composite materials are fabricated without proper design. Unlike airplane or automobile parts, prototype test is impossible. One cannot destroy 10 story buildings or 100 meter-long bridges. In order to realize “composites in construction”, the following subjects must be studied in detail, for his design: Concept optimization, Simple method of analysis, Folded plate theory, Size effects in failure, and Critical frequency Unlike the design procedures with conventional materials, his design should include material design, selection of manufacturing method, and quality control methods, in addition to the fabrication method.

• IE interfaces
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• v.12 no.1
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• pp.158-165
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• 1999

One solution to the estimation of product reliability during the development phase is to measure reliability improvement over time and compare this improvement to previous product development progress. This paper presents the reliability growth theory and applies it to some subsystems of vehicles during their design, development and prototype testing. The data presented illustrates explicitly the prediction of the reliability growth in the product development cycle. The application of these techniques is a part of the product assurance function that plays an important role in product reliability improvement.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.571-575
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• 2001

A protection scheme for hybrid active power filters, which is combined shunt passive filter and small rated series active filter, is presented and analyzed in this paper. The proposed series active power filter operated as a high impedance 'k($\Omega$)' to the fundamental component when over current occurs in the power distribution system, and three control strategies are proposed in this paper. The first is the method by detecting the fundamental source current through the p-q theory, the second is the method by detecting the fundamental component of load current in Synchronous Reference Frame (SRF) and the third is the method by detecting the input voltage. When the over current occurs in the power distribution system, the proposed scheme protects the series active power filter without additional protection circuits. The validity of proposed protection scheme is investigated through experimental result for the prototype hybrid active power filter system.