• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2260-2262
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• 2000

In this paper, micromirror which can rotate 45 degree is designed, analyzed and fabricated. The micromirror is parallel to the substrate initially. When external magnetic field is applied, a micromirror can rotate to align its easy axis to the field. The size of micromirror array is $10{\times}10$. The mirror plate and spring is made of aluminium, and nickel is used as soft magnetic material. To obtain 45 degree angular deflection, dimension ratio between stopper length and thickness of sacrificial layer is properly selected. By using electrostatic force, individual actuation is possible.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.11a
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• pp.777-783
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• 2000

As the disk rotation speed increases in information storage devices, aerodynamically excited disk vibration is induced by airflow around the disk. This paper investigates both experimental and theretical studies on the flutter instability. From the experimental results using an ASMO disk, it is found that the three nodal diameter mode of the optical disk experiences its flutter instability around 8750 rpm. At the flutter speed, the amplitude of the corresponding mode increases dramatically and the backward natural frequency does not increase with increasing rotational speeds. The experimental results on flutter instability are compared with analytical predictions.

• Korean Architects
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• s.630
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• pp.16-21
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• 2021

서울 용산구 한강대로에 위치한 529제곱미터 규모의 2층 사옥 '유신재'. 일제강점기 시절 건설된 벽돌(연와조)과 철근콘크리트조, 목조 트러스 지붕 구조의 이 낡은 건물은 준공(1926.06.23)된 지 90년이 훌쩍 넘었으며, 건물주인 (주)유신이 역삼동으로 사옥을 이전한 후 30여 년간 문서보관소로 사용돼왔다. 그런 이 건물이 지난 4월부터 8월까지의 공사를 거쳐 유신건축(주.유신건축 종합건축사사무소)의 사옥으로 새롭게 태어났다. 근 100여 년의 흔적을 그대로 간직한 건물의 리모델링 설계자는 유신건축의 김지덕 건축사(부(父))·김우영 건축사(자(子)/ 영국왕립건축사) 부자(父子)다. 지난 9월 24일, 유신재에서 함께 일하고 있는 두 부자 건축사의 이야기를 직접 들어보았다.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.85-92
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• 2003

Generally, ordinary portland cement(OPC) is widely used for grouting to reduce permeability of ground under the foundations of structures. But, it is hard to be injected into the microscopic voids, fissures and crevices in soil or rock formation for the OPC material. Therefore new method what is called MSG(Micro Silica Grouting) has been developed recently to improve the weak point of the OPC material. In this case study, in order to verify performance of the MSG's water cut-off, trial injections were performed in rear of CIP(Cast in Place Pile) on the site A(weathered soil) and B(alluvial soil) that are constructed for the subway No. 9 nowadays. To take the proper grouting method of the MSG in the trial injecting, the injections are carried out for grouting types(constant pressure or fixed Quantity) and grouting methods(1.5shot or 2.0shot) and to confirm the effects of water cut-off and the injection range of the MSG, the tests of permeability and indicator(phenolphthalein) response were performed before and after the injection. Through the tests results, we could affirm the effects of water cut-off of the MSG and the injection range for the weathered and alluvial soil layers near the Han River. Finally we could make sure the application of the MSG method in actual construction under the layers.

• Journal of Broadcast Engineering
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• v.19 no.2
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• pp.227-239
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• 2014

This paper proposes an enhance prediction for conventional near-lossless coder to effectively lower external memory bandwidth in image processing SoC. First, we utilize an already reconstructed green component as a base of predictor of the other color component because high correlation between RGB color components usually exists. Next, we can improve prediction performance by applying variable block size prediction. Lastly, we use minimum internal memory and improve a temporal prediction performance by using a template dictionary that is sampled in previous frame. Experimental results show that the proposed algorithm shows better performance than the previous works. Natural images have approximately 30% improvement in coding efficiency and CG images have 60% improvement on average.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.5
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• pp.475-484
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• 2020

Individual curing process of each layer in two resin composites can be caused the separation between two layers. In this study, co-curing process for two resin composites is suggested to improve the inter-layer bonding. Glass fiber reinforced composites with phenolic and epoxy resins were manufactured by co-curing process, and several types of glass/phenolic composites were considered to confirm the application on two resin composites. Experiments for smoke resistance, scratch resistance and flexural strength were carried out to verify requirements corresponding to thermal and mechanical environments. It was validated that two resin composites with phenolic resin impregnated prepreg exhibits good thermal and mechanical characteristics, and it can serve as highly effective composite structures in aerospace and many industry areas.

• The Journal of the Acoustical Society of Korea
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• v.20 no.8
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• pp.19-23
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• 2001

DSP-based implementation is pervasive in wireless communication parts for systems and handsets according to developing high-speed and low-power programmable Digital Signal Processor (DSP). In this paper, we present a real-time implementation of multi-channel Adaptive Multi-rate (AMR) speech coder. The real-time implementation of an AMR algorithm is achieved using 32-bit fixed-point TMS320C6202 DSP chip that operates at 250 MHz. We performed cross compile, linear assembly optimization and TMS320C62xx assembly optimization for real-time implementation. Furthermore, speech data input/output function and communication function with external CPU is included in an AMR speech coder. The AMR Speech coder developed using DSP EVM board was evaluated in ETRI IMT-2000 Test-bed system.

• Journal of Korean Classical Literature and Education
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• no.15
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• pp.265-301
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• 2008

In this writing, issued beauty as Hyangga(향가) creative motivation into the focus, its expression modality is discussed and then an aesthetic sense of Sil-la is considered. For its research, in "Samkukyusa"("삼국유사") some Hyangga - , , , - that have phraseologies for beauty meaning are choose for the discuss. First, beauty as Hyangga(향가) creative motivation were expressed by above methods. 1. Beauty as desires for acquisition and confirmation in 2. Beauty that the subject (the writer) looked upon in 3. Beauty that felt pathetic for declining in 4. Beauty that arouse from disillusion in Second, an aesthetic sense of Sil-La in "Samkukyusa"("삼국유사") showed as the above. 1. Physical beauty that Sil-La were attracted by 2. Beauty as the glorified object that Sil-La were attracted by 3. Beauty as the virtue notion that Sil- La were attracted by In consequence, it is discussed that Sil-La had an aesthetic sense as the perfect virtue united the transcendence and the real.

• Proceedings of the Korean Society of Computer Information Conference
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• 2022.01a
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• pp.227-230
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• 2022

본 연구에서는 실질적 학습자가 교수자로 착각을 한 상태에서 아바타를 학습시키는 과정을 통해 학습이 되게 하는 구조를 설계하고 제안하였다. 시스템 관리자와 교육자료 형성자를 제외하면, 교수자로 착각하고 있는 '학습자'와 학습자의 공부를 위해 노력하는 학습 가이드 역할을 '학습 관찰자', 학습이 되는 아바타로 구성된다. '학습 관찰자'는 학습 방향을 제시하여 아바타가 활동하는 방향을 지시하게 되며, 아바타는 지시된 방향에서 1:1 학습과 같은 형태로 교수자 입장 학습자에게 공부도움을 요청하게 된다. 아바타의 학습은 인공지능 지도 학습 방법을 이용하여 학습되도록 하며, 교수자로 착각하는 학습자는 아바타 학습 시 아바타에 의해 슬며시 제공되는 학습 자료를 참고하며 아바타를 공부시키게 되는 데 아바타를 공부시킨다고 노력하는 과정이 교수자로 착각된 학습자가 공부가 되는 것이다. 또한 이렇게 학습하는 과정을 거쳐 지식이 성장한 아바타는 아바타들이 경쟁하는 경진 대회에 참가하게 되며 교육자로 착각하는 학습자는 관전 또는 코치를 하며 학습을 하게 된다. 이러한 방법을 통해 교육자로 착각하는 학습자는 부모의 마음으로 적극적으로 공부를 하게 유도하며, 흥미를 갖고 공부를 하게 할 뿐 아니라, 가르치는 사람에 준하는 깊이 있는 지식을 갖도록 유도하며, 본 시스템과 온라인 오프라인을 통해 연결 되게 한 운동 기구 및 운동 환경을 이용하여 운동 하도록 유도하고 파워가 되도록 하여 운동 활동을 유도하며, 단계 마다 적당한 보상 점수들이 제공되도록 하여 지덕체가 성장되도록 하는 설계이다.

• Journal of the Korean Society of Earth Science Education
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• v.16 no.3
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• pp.374-384
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• 2023

This study investigated the impact on pre-service teachers during the development of an integrated science education program, emphasizing group intelligence, values, and software application in response to societal demands. The results revealed several key findings. Firstly, the development of an integrated science education program utilizing group intelligence enhanced the learning motivation of pre-service teachers, particularly demonstrating improvements during the implementation phase. Secondly, the group intelligence-based development of the integrated science education program cultivated the group intelligence competence of pre-service teachers, manifesting positive effects throughout the entire process of program development, demonstration, and feedback. Thirdly, it was evident that the integration of software and individual values into science curriculum requires specialized support.