• Title/Summary/Keyword: 표면 침식

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Using a computer color image automatic detection algorithm for gastric cancer (컴퓨터 컬러 영상을 이용한 위암 자동검출 알고리즘)

  • Han, Hyun-Ji;Kim, Young-Mok;Lee, Ki-Young;Lee, Sang-Sik
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.4 no.4
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    • pp.250-257
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    • 2011
  • This experiment present the automatic detection algorithm of gastric cancer that take second place among all cancers. If an inflammation and a cancer are not examined carefully, early ones have difficulty in being diagnosed as illnesses than advanced ones. For diagnosis of gastric cancer, and progressing cancer in this study, present 4 algorithm. research team extracted an abnormal part in stomach through the endoscope image. At first, decide to use shading technique or not in each endoscope image for study. it make easy distinguish to whether tumor is existing or not by putting shading technique in or eliminate it by the color. Second. By passing image subjoin shading technique to erosion filter, eliminate noise and make give attention to diagnose. Third. Analyzing out a line and fillet graph from image adding surface shade and detect RED value according to degree of symptoms. Fourth. By suggesting this algorithm, that making each patient's endscope image into subdivision graph including RED graph value, afterward revers the color, revealing the position of tumor, this study desire to help to diagnosing gastric, other cancer and inflammation.

Evaluation of Corrosion and Cavitation Erosion Resistance of Sealed Aluminum Alloy after Anodizing Treatment in Seawater (양극산화 후 실링처리된 알루미늄 합금의 해수 내 내식성과 캐비테이션 침식 저항성 평가)

  • Park, Il-Cho;Lee, Jung-Hyung;Han, Min-Su;Kim, Seong-Jong
    • Journal of the Korean institute of surface engineering
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    • v.51 no.2
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    • pp.87-94
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    • 2018
  • Various sealing techniques were applied to the anodized 5083 aluminum alloy for marine environment to reduce corrosion and cavitation erosion damage. Electrochemical experiments and cavitation erosion tests were conducted to evaluate the corrosion resistance and cavitation resistance of the anodic oxide film treated with sealing in natural seawater solution. Then, damaged surface morphology was analyzed by scanning electron microscope(SEM) and 3D microscope. As the results of the electrochemical experiments, it was observed that the surface damage of all the experimental conditions in the anodic polarization experiment was locally grown by the combination of crack and corrosion damage. In the Tafel analysis, the corrosion resistance of all sealing treatment conditions was improved compared to the anodizing. On the other hand, cavitation erosion tests showed that the anodizing and all the sealing treatment conditions generated local pit damage by cavitation erosion attack and grew to crater damage in the observation of damaged surface by SEM. Also, the weight loss and the surface damage depth measured with the experiment time presented that most of the sealing treatment conditions showed better cavitation erosion resistance than the anodizing, and they had an incubation period at the beginning of the experiment.

DEM Generation of Tidal Flat by the Area Based Matching Method Using Digital Aerial Stereo Images (디지털 입체 항공사진의 영역기반매칭법에 의한 갯벌 DEM 제작)

  • Lee, Hyo-Seong;Ahn, Ki-Weon;Kim, Duk-Jin
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.3
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    • pp.42-52
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    • 2010
  • The purpose of this study is to produce digital elevation model (DEM) in the Jebu tidal flat, one of the west coast of the Korean Peninsula, by means of photogrammetric techniques from aerial digital stereo-images. Produced DEM would be become the fundamental data for change detection of the sediment and erosion. To do so, epipolar line is established by relative orientation. Area-based matching is then carried out based on this line and matching size according to surface property of tidal flat after a classified image is produced from reflectance and texture of the surface. As the results, DEM generated by the proposed method showed subtle changes in height more precisely than DEM using the fixed matching size and DEM by the commercial S/W in the region, such as tidal flats having few level differences.

Evaluation of Corrosion Resistance using Electro-chemical Methods for the High-Durability Concrete exposed to Marine Condition (해양환경에 노출된 고내구성 콘크리트의 전기화학적기법을 이용한 부식저항성 평가)

  • Yang, Eun-Ik;Kim, Myung-Yu;Lee, Dong-Gun;Han, Sang-Hun
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.4
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    • pp.320-328
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    • 2007
  • The durability of marine concrete structures is severely degraded by corrosion due to seawater attack and diffusion of chloride in concrete. The deduction of durability causes high repair cost for maintenance of marine concrete structure. So, the applicability of high-durable materials is investigated to improve the durability in marine concrete structures. For these, the characteristics of corrosion prevention of marine concrete structures mixed with the mineral admixtures(SF, FA and BFS), the modified steel(stainless and coating steel), and corrosion inhibitors are evaluated using electro-chemical methods. As a results of this study, it is quantified for the effect of promotion of durability by high-durability materials in marine concrete structures.

Development of High Erosion Resistant Fe-based Alloy for Continuous Hot Dipping Line (연속용융 도금라인 용 고내침식 Fe계 합금 개발)

  • Baek, Min-Sook;Kim, Yong-Cheol;Baek, Kyeong-Cheol;Kwak, Joon-Seop;Yoon, Dong-Joo
    • Journal of the Korean institute of surface engineering
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    • v.53 no.3
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    • pp.95-103
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    • 2020
  • In this study, the material used in the hot dip galvanizing equipment was poorly corrosion-resistant, so it was performed to solve the cost and time problems caused by equipment replacement. The theoretical calculation was performed using the DV-Xα method(Discrete Variational Local-density approximation method). The alloy (STS4XX series) of the equipment currently used has a martensite phase. Therefore, the theoretical calculation was performed by applying P4 / mmm, which is a tetragonal structure. The new alloy was chosen by designing theoretical values close to existing materials. Considering elements that contribute to corrosion, most have high prices. Therefore, the design was completed by adjusting the content using only the components of the reference material in the theoretical design. The final design alloys were chosen as D6 and D9. Designed D6 and D9 were dissolved and prepared using an induction furnace. After the heat treatment process was completed, the corrosion rate of the alloys was confirmed by using the potentiodynamic polarization test. The surface of the prepared alloys were processed horizontally and then polished to # 1200 using sand paper to perform potentiodynamic polarization test. Domestic products: 4.735 mpy (mils / year), D6: 0.9166 mpy, D9: 0.3372 mpy, alloys designed than domestic products had a lower corrosion rate. Therefore, the designed alloy was expected to have better erosion resistance.

Techniques for Characterizing Surface Deterioration of Epoxy Exposed to Ozone Damage (오존에 노출된 에폭시 코팅재의 표면 열화특성 평가기술)

  • Choi, Sung-Min
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.18 no.3
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    • pp.167-177
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    • 2014
  • New technologies for water purification are continuously emerging to address global water quality problems, and one such technology involves advanced hermetic water purification facilities made by concrete that utilize ozone treatment processes. Better knowledge about surface deterioration of epoxy coating exposed to ozone treatment is needed as a foundation for development of improved methods and materials in the future. This study utilized atomic force microscopy (AFM), nanoindentation methods, and existing indirect methods such as visual observation, changes in mass, surface observation and chrominance analysis, to evaluate epoxy water-resistance and anti-corrosiveness. This study considered six different epoxy formulations to assess typical degradation characteristics of epoxy surfaces with regard to water-resistance/anti-corrosiveness. AFM and nanoindentation techniques emerged as promising direct methods with potential to provide quantitative measures of surface quality that are improvements upon existing indirect methods. The experiments also confirmed that some of the epoxy-coatings were severely iMPacted by ozone exposure, and thus the results demonstrate that concern about such deterioration is justified.

Characterization of Bacterial ${\alpha}-Amylase$ by Determination of Rice Starch Hydrolysis Product (쌀전분(澱粉) 분해물(分解物) 분석(分析)에 의한 세균성(細菌性) ${\alpha}-Amylase$의 작용(作用) 특성(特性))

  • Kim, Hae-Yeong;Park, Kwan-Hwa
    • Applied Biological Chemistry
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    • v.29 no.3
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    • pp.248-254
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    • 1986
  • The product specificity of Bacillus ${\alpha}-amylase$ on raw rice starch has teen studied by using HPLC and scanning electron microscopy (SEM). Analysis of starch degradation products digested by ${\alpha}-amylase$ showed considerable differences between raw and gelatinized rice. The hydrolysis of raw rice starch resulted in formation of more glucose and maltose than those of gelatinized starch. SEM revealed characteristic enzyme degradation patterns. Hollow curvatures were observed in gelatinized starch, indicating the substrate is hydrolyzed in the interior of the starch chain by Bacillus ${\alpha}-amylase$. In contrast, raw starch were hydrolyzed from the end of the substrate, resulting in pinholes over the surface of the starch granules.

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Geoarchaeology of the Piseo-ri Paleolithic site, Muan (무안 피서리구석기유적의 지질.고고학적 특성)

  • Lee, Heon-Jong;Chung, Chull-Hwan;Park, Sung-Tan
    • The Korean Journal of Quaternary Research
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    • v.24 no.2
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    • pp.13-21
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    • 2010
  • The Piseo-ri site in Muan provides significant data in investigation on the Paleolithic sites in the southwest coast of Korea. Stratigraphic and geological analysis indicates that the characteristic of soil wedge can vary in accordance with soil property and relief of paleo-surface. Considering that the cultural layer was deposited after the Last Glacial Maximum, co-occurrence of the late Middle to early Upper Paleolithic stone tools suggests a possibility of redeposition of different ages resulted from active erosion. The result shows that the distribution of the Paleolithic tools and the property of soil wedge could be controlled by environmental conditions such as relief of paleo-surface and climate.

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Applications and Prospects of Calcium Carbonate Forming Bacteria in Construction Materials (건축공학분야에서 탄산칼슘형성세균의 응용과 전망)

  • Park, Sung-Jin;Ghim, Sa-Youl
    • Microbiology and Biotechnology Letters
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    • v.40 no.3
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    • pp.169-179
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    • 2012
  • Microbiological calcium carbonate precipitation (MCCP) is being applied for the aesthetic restoration of cement buildings destroyed by biochemical processes and to block water penetration into the cement's inner structure. After determining the advantages of this technique, many related studies in the area of architecture concerning the application of microorganisms to improve construction material have been reported in both America and Europe. The techniques compatibility with cement material is especially interesting because of the needed screening of various calcium carbonate forming-bacteria and the required development of their application methods. The purpose of this review is to describe the mechanism of MCCP and related researches with eco-friendly construction materials. Mainly, we describe the methodological studies focused on biodeposition on the surface of building materials and the research trends concerning the addition of microorganisms to improve the durability of cement structures. Additionally, the concepts and technical aspects focused on the development of self-healing smart concrete, with the use of multi-functional bacteria, have been considered.

A Study on the C.T.I in Phenolic Resin (Phenolic Resin의 C.T.I에 관한 연구)

  • 이보호;박동화
    • The Proceedings of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.1 no.2
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    • pp.62-69
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    • 1987
  • In the thesis research on the C.T.I for the borne by tracking phenolic resin, electolytic errosion appearance of electrode materials causes the part of electrode to increase the failure of tracking. $\circled1$ In the material of insulation in which C.T.I has 350 degree or so, We can obtain the constant value by Cu.Zn electrode than Pt electrode. $\circled2$ C.T.I value has noting to do with resistance rate of electrolyte. $\circled3$ As the contact angle of interface grow, the starting electric stress of corona and the value of C.T.I increase.

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