• Title/Summary/Keyword: Poor Solution

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Hydroxyapatite Formation on Fluoride Bioactive Glasses coated on Alumina (알루미나에 코팅된 불화물 생체유리에의 수산화 아파타이트 형성)

  • 안현수;이은성;김철영
    • Journal of the Korean Ceramic Society
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    • v.36 no.10
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    • pp.1087-1093
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    • 1999
  • Bioglass which is one of the surface active bionmaterials has a good biocompatibility but a poor mechanical strength, In the present work therefore two types of fluoride-containing bioglasses were coated on an alumina to improve mechanical strength. Crystallization of the coating layer and the hydroxyapatite formation on the bioactive glass coatings in tris-buffer solution were studied. When bioactive glass coated alumina was heat-treated Na2CaSi3O8 crystal was formed on the layer at lower temperature while wollastonite(CaSIO3) was obtained at higher temperature. Hydroxyapatite forming rate on the coating layer with Na2CaSi3O8 crystal was delayed with SiO2 contents in glass composition. However the hydroxyapatite was developed in 20minutes regardless SiO2 contents when the coating layer crystallized into wollastonite. More amount of P3+ ions were leached out of the coating layer with wollastonite than that with Na2CaSi3O8 crystal while Na+ and Ca2+ ions were leached out more easily from the Na2CaSi3O8 crystal containing coating layer.

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Effective Artificial Neural Network Approach for Non-Binary Incidence Matrix-Based Part-Machine Grouping (비이진 연관행렬 기반의 부품-기계 그룹핑을 위한 효과적인 인공신경망 접근법)

  • Won, You-Kyung
    • Journal of the Korean Operations Research and Management Science Society
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    • v.31 no.4
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    • pp.69-87
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    • 2006
  • This paper proposes an effective approach for the part-machine grouping(PMG) based on the non-binary part-machine incidence matrix in which real manufacturing factors such as the operation sequences with multiple visits to the same machine and production volumes of parts are incorporated and each entry represents actual moves due to different operation sequences. The proposed approach adopts Fuzzy ART neural network to quickly create the Initial part families and their machine cells. A new performance measure to evaluate and compare the goodness of non-binary block diagonal solution is suggested. To enhance the poor solution due to category proliferation inherent to most artificial neural networks, a supplementary procedure reassigning parts and machines is added. To show effectiveness of the proposed approach to large-size PMG problems, a psuedo-replicated clustering procedure is designed. Experimental results with intermediate to large-size data sets show effectiveness of the proposed approach.

The Hazard Viz-platform for the Establishment of Heatwave Response Strategies (폭염 대응전략 수립을 위한 폭염위험도 시각화 플랫폼)

  • Kim, Miyun
    • Journal of Korea Multimedia Society
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    • v.23 no.5
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    • pp.683-699
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    • 2020
  • Recently, the earth's highest temperature is rising due to severe climate change and heat wave. In addition, due to the increase of elderly population over 65, the number of heat patients is also increasing. In particular, the elderly who live alone in poor living environments, the lower income group, and the socially disadvantaged, such as children and pregnant women, are exposed to the dangers of heat waves, so the government's practical measures are urgently needed. In this study, we will build a visualization platform for each level of heat wave and provide the necessary countermeasure solution according to the heat wave risk. "The Hazard Visualization Platform for Heatwave" provide not only simple information, but also a customized safety service for citizens to prevent heatwaves, respond to heatwaves, and utilize heat wave information.

Surimi Preparation from mechanically Deboned Chicken Meat (기계발골 계육으로부터 닭고기 수리미의 제조)

  • 이성기
    • Korean Journal of Poultry Science
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    • v.26 no.2
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    • pp.85-95
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    • 1999
  • The mechanically deboned chicken meat(MDCM) has several limits in using for in using for in processed meat products as a main material because of poor color and textural properties, chance of microbial contamination and lipid oxidation. There has been a growing interest all over world in the application of MDCM to the surimi process. The surimi made from MDCM contains a high concentration of myofibrillar protein since this processing involves repeated washing processes with an aqueous solution in order to remove heme pigments, fat and other undesirable substances. The quality of the surimi made from MDCM is affected by various processing factors, such as kinds of wash solution, ion strength, washing cycle, temperature, pH changes, composition, part of muscle, particle size, and rigor state etc. A number of researchers havee investigated the effect of the various washing conditions on the properties of surimi gels. A fuller information of all the factors affecting surimi processing and gel formation by heat-induced gelation has not been known yet.

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Dyeing Properties of Silk Fabric Dyed with Black Soybean Extracts (흑두 추출물에 의한 견직물의 염색성)

  • Ryu Jung Min;Jeon Young Sil;Kim In Hoi;Nam Sung Woo
    • Textile Coloration and Finishing
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    • v.17 no.5 s.84
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    • pp.20-25
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    • 2005
  • The colorants were extracted from black soybean using a buffer solution. Dyeing properties and the fastness of silk fabric dyed with black soybean extracts were investigated. K/S values of dyed fabric were increased with concentration of black soybean extracts. Magnesium sulfate, nickel sulfate and calcium chloride as mordants are used to obtain reddish purple color. Optimum dyeing temperature of black soybean extracts was $30^{\circ}C$. Fastness were generally good except for light fastness which was extremely poor.

EA as an Actionable Architecture

  • Jeong, Chanki
    • Journal of Information Technology and Architecture
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    • v.9 no.2
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    • pp.133-142
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    • 2012
  • Gartner predicts that by 2012, 40% of EA programs will be stopped due to poor execution and the failure of delivering business value. An organization needs a practical solution to achieve an EA vision. The EA essential approach should be that of business service and process orientation than systems and IT orientation. We propose an Actionable Enterprise Architecture (AEA) which is based on BPM (Business Process Management) and SOA (Service Oriented Architecture), and connected to service & process orientation and engineering. The architecture proposed provides traceability between service-oriented enterprise architecture and its solution. The proposed architecture can transform enterprise architecture from conceptual to physical levels (solutions) with a service and business process paradigm.

Resistivity and Calibration Error Estimations for Small-Loop Electromagnetic Method

  • Sasaki, Yutaka;Son, Jeong-Sul;Kim, Chang-Ryol;Kim, Jung-Ho
    • 한국지구물리탐사학회:학술대회논문집
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    • 2007.06a
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    • pp.167-172
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    • 2007
  • The frequency-domain small-loop electromagnetic (EM) instruments are increasingly used for shallow environmental and geotechnical surveys because of their portability and speed. However, it is well known that the data quality is generally so poor that quantitative interpretation of the data is not justified in many cases. We present an inversion method that allows the correction for the calibration errors and also constructs multidimensional resistivity models. The key point in this method is that the data are collected at least at two different heights. The forward modeling used in the inversion is based on an efficient 3-D finite-difference method, and its solution was checked against 2-D finite-element solution. The synthetic and real data examples demonstrate that the joint inversion recovers reliable resistivity models from multi-frequency data severely contaminated by the calibration errors.

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Performance Analysis of INS/GPS Integration System (INS/GPS 결합방식에 따른 성능분석)

  • Park, Young-Bum;Lee, Jang-Gyu;Park, Chan-Gook
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2433-2435
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    • 2000
  • Inertial Navigation System(INS) provides short-term accurate navigation solution but its error grows with time due to integration characteristics. Meanwhile, Global Positioning System(GPS) provides long-term stable solution but it has poor error characteristics in high dynamic region. So for its synergistic relationship, an integrated INS/GPS systems has been widely used as an advanced navigation system. Generally, two kinds of integration method are used. One is loosely coupled mode which uses GPS-derived position and velocity as measurements in an integrated Kalman filter. The other is tightly coupled one which uses pseudorange and pseudorange rate as Kalman filter measurements. In this paper the system error models and observation models for two kinds of integrated systems are derived, respectively, and their performance are compared through Monte-Carlo simulations.

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Catalytic Effects of Barium Carbonate on the Anodic Performance of Solid Oxide Fuel Cells

  • Yoon, Sung-Eun;Ahn, Jae-Yeong;Park, Jong-Sung
    • Journal of the Korean Ceramic Society
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    • v.52 no.5
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    • pp.350-355
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    • 2015
  • To develop ceramic composite anodes of solid oxide fuel cells without metal catalysts, a small amount of barium carbonate was added to an $(La_{0.8}Sr_{0.2})(Cr_{0.5}Mn_{0.5})O_3(LSCM)$ - YSZ ceramic composite anode and its catalytic effects on the electrode performance were investigated. A barium precursor solution with citric acid was used to synthesize the barium carbonate during ignition, while a barium precursor solution without citric acid was used to create hydrated barium hydroxide. The addition of barium carbonate to the ceramic composite anode caused stable fuel cell performance at 1073 K; this performance was higher than that of a fuel cell with $CeO_2$ catalyst; however, the addition of hydrated barium hydroxide to the ceramic composite anode caused poor stability of the fuel cell performance.

The Influence of Cyclic Treatments with H₂O₂ and HF Solutions on the Roughness of Silicon Surface

  • 이혜영;이충훈;전형탁;정동운
    • Bulletin of the Korean Chemical Society
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    • v.18 no.7
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    • pp.737-740
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    • 1997
  • The influence of cyclic treatments with H2O2/DIW (1 : 10) and HF/DIW (1 : 100) on the roughness of silicon surface in the wet chemical processing was investigated by atomic force microscopy (AFM). During the step of the SC-1 cleaning, there is a large increase in roughness on the silicon surface which will result in the poor gate oxide breakdown properties. The roughness of the silicon wafer after the SC-1 cleaning step was reduced by cyclic treatments of hydrogen peroxide solution and hydrofluoric acid solution instead of HF-only cleaning. AFM images after each step clearly illustrated that the average roughness of silicon surface after three times treatments with H2O2 and HF solutions was reduced by 10 times compared with that after the SC-1 cleaning step.