• Proceedings of the Korea Information Processing Society Conference
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• 2017.11a
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• pp.75-77
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• 2017

디지털 제어와 사물 인터넷을 통한 네트워크 기반 제어가 확산되면서 정밀 제어를 위한 양자화 오류에 대한 고려의 중요성이 증가하고 있다. 본 연구에서는 이산 시간 출력 궤환 제어 시스템에서 제어 신호 생성에 사용되는 시스템 출력 신호에 양자화 오류가 있을 때, 리아푸노프 시스템 안정성을 보장하는 조건을 선형 행렬 부등식을 통하여 제시한다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.7
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• pp.982-987
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• 1990

In this paper, the difference between call processing routing of general purpose ESS and that of special purpose ESS, such a TDX-ACD, was specified by analyzing the call processing capacity of special purpose ESS. Then the load sharing method was proposed in orde to reduce the overload condition in specific processors. Finally, measirement value was illustrated nad compared with simulation value.

• Proceedings of the Korea Information Processing Society Conference
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• 2018.05a
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• pp.592-593
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• 2018

사물 인터넷 환경에서 제어 시스템이 네트워크에 연결되면서 정밀 제어를 위한 양자화에 대한 고려가 중요해 지고 있다. 본 연구에서는 프로세스 잡음이 존재하는 이산 시불변 선형 시스템에서 실용적 관찰성을 달성하기 위해서 필요로 하는 데이터 양에 대한 조건을 제시한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.11a
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• pp.639-640
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• 2008

최근 개발이 활발한 IT 기술 중 웹 기술을 응용하여 여러 가지 산업 기기와 그 부품들에 대하여 상태의 온라인 감시에 기반을 둔 진단 및 유지보수 등을 통합적으로 관리 할 수 있는 시스템의 개발에 관하여 소개하였다. 지능화되고 복잡해지기 쉬운 현대의 다양한 유지보수 기법들의 개발이 완료된 후, 기존 시스템의 통합과 사용법 숙지 등의 어려움으로 시너지 효과가 발휘되지 않는 문제점을 극복하고 다양한 사용자들을 위한 원격응용이 가능할 것이다.

• Applied Biological Chemistry
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• v.41 no.2
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• pp.147-152
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• 1998

As a part of investigation for utilizing seafood processing by-products as a functional food source, we investigated the processing condition (extraction methods and autoclaving time) of a functional calcium-based powder from fish bones and its characteristics. The calcium-based powder from Alaska pollack bone by autoclaving in water showed lower in the calcium content and higher in the yields and the soluble calcium ratio than those from fish bone by the other calcium extraction methods. As the autoclaving time elapsed up to 40 min, the content and soluble ratio of calcium increased, and the yield decreased. On the other hand, there were no difference found in those among calcium-based powders autoclaved for 40 min and over. Judging from the results, the calcium-based powder from Alaska pollack autoclaved in water for 40 min (CAP) was superior to those from fish bone by the other processing condition. The CAP was mostly solublized by shaking $(37^{\circ}C)$ for 1 hr at the acidic condition (pH 2.0). The soluble calcium ratio of acid-solublized CAP was about 59% by shaking $(37^{\circ}C)$ for 3 hr and over at the neutral condition (pH 7.0).

• Journal of Korea Foundry Society
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• v.18 no.5
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• pp.474-480
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• 1998

Microstructural characteristics of semi-solid state processed hypereutectic Al-Si alloys have been investigated. Main concern of the present study is to investigate the effects of P and Sr addition on the size and morphology change of the primary Si particles. Refinement of the primary Si particles was observed with the addition of P and Sr at the early stage of semi-solid state processing, but such a refining effects became negligible resulting in Si particles with a near-spherical morphology with continuous stirring. This implies that the microstructural transformation mechanism became more dependent to stirring effects than to the alloying effects during semi-solid state processing. Brittle fracture and agglomeration were proposed as the mechanisms for microstructural alterations during semi-solid state processing.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.98-102
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• 2009

Almost all injection molds have multi-cavity runner system for mass production, which are designed with geometrically balanced runner system in order to accomplish filling balance between cavity to cavity during processing. However, even though geometrically balanced runner is used, filling imbalance has been observed. Filling imbalance could be decreased by modifying processing conditions such as injections rate, mold temperature, injection pressure, melt temperature that are related to shear, viscosity. In this study, a series of experiment was conducted to investigate filling imbalance variation when modifying runner layout and polymer and to determine which processing condition influences as the primary cause of filling imbalance in geometrically balanced runner system. The filling imbalance was decreased up to result range of $3{\leq}DFI{\leq}8(%)$ by using a new runner system for balanced filling.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.97-105
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• 1998

The fiber oriented condition inside fiber reinforced composite material is a basic factor of mechanical properties of composite materials. It is very important to meausure the fiber orientation angle for the determination of molding conditions, mechanical characteristics, and the design of composite materials. In the work, the fiber orientation distribution of simulation figure plotted by PC is measured using image processing in order to examine the accuracy of intersection counting method. The fiber orientation function measured by intersection counting method using image processing is compared with the calculated fiber orientation function. The results show that the measured value of fiber orientation function using intersection counting method is lower than the calculated value, because the number of intersection between the scanning line and the fiber with smaller fiber aspect ratio is counted less than with larger fiber aspect ratio.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1991.11a
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• pp.87-94
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• 1991

This Paper is to aim the microdefect evaluation of semiconductor Package into a quantitative from NDI's image processing of ultrasonic wave. Accordingly, for the detection of delamination between the Joining condition of boundary microdefect of semiconductor packaga the result from sampling original image, histogramming, binary image or image processing of multinumerloal value is such as the follows. ([) The least limitation from the microdefect detection of the semiconductor package by surveying high ultrasonic wave seems to be about 0.8 $\mu\textrm{m}$ in degree. (2) A result of applying the image processing of multinumerical value to the semiconductor package it was possible to devide the Category into the effectiveness.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.455-460
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• 2007

A self-sensing circuit for piezo inkjet has been designed in order to monitor the operating condition during printing. In order to verify the circuit, both ink droplet images from strobe LED and vibration signals from the laser vibrometer were measured and compared with self-sensing signal. Experimental results show that self-sensing signal was effective in detecting the pressure wave change due to the bubble trapped in inkjet printhead.