• Title/Summary/Keyword: 제조기법

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Locates the Sunken Ship 'Dmitri Donskoi' using Marine Geophysical Survey Techniques in Deep Water (지구물리 탐사기법을 이용한 심해 Dmitri Donskoi호 확인)

  • Yoo, Hai-Soo;Kim, Su-Jeong;Park, Dong-Won
    • 한국지구물리탐사학회:학술대회논문집
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    • 2004.08a
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    • pp.104-117
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    • 2004
  • Dmitri Donskoi, which went down during the Russo-Japanese War occurred 100 years ago, was found by using geophysical exploration techniques at the 400 m water depth of submarine valley off Jeodong of Ulleung Island. In the submarine area with the rugged seabed topography and volcanic seamounts, in particular, the reliable seabed images were acquired by using the mid-to-shallow Multibeam exploration technique The strength of corrosion (causticity) of the sunken Donskoi, measured by the electrochemical method, decreased to 2/5 compared with the original strength.

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Development of Quality Assurance Program for the On-board Imager Isocenter Accuracy with Gantry Rotation (갠트리 회전에 의한 온-보드 영상장치 회전중심점의 정도관리 프로그램 개발)

  • Cheong, Kwang-Ho;Cho, Byung-Chul;Kang, Sei-Kwon;Kim, Kyoung-Joo;Bae, Hoon-Sik;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.17 no.4
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    • pp.212-223
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    • 2006
  • Positional accuracy of the on-board imager (OBI) isocenter with gantry rotation was presented in this paper. Three different type of automatic evaluation methods of discrepancies between therapeutic and OBI isocenter using digital image processing techniques as well as a procedure stated in the customer acceptance procedure (CAP) were applied to check OBI isocenter migration trends. Two kinds of kV x-ray image set obtained at OBI source angle of $0^{\circ},\;90^{\circ},\;180^{\circ},\;270^{\circ}$ and every $10^{\circ}$ and raw projection data for cone-beam CT reconstruction were used for each evaluation method. Efficiencies of the methods were also estimated. If a user needs to obtain an isocenter variation map with full gantry rotation, a method taking OBI image for every $10^{\circ}$ and fitting with 5th order polynomial was appropriate. However for a mere quality assurance (QA) purpose of OBI isocenter accuracy, it was adequate to use only four OBI Images taken at the OBI source angle of $0^{\circ},\;90^{\circ},\;180^{\circ}\;and\;270^{\circ}$. Maximal discrepancy was 0.44 mm which was observed between the OBI source angle of $90^{\circ}\;and\;180^{\circ}$ OBI isocenter accuracy was maintained below 0.5 mm for a year. Proposed QA program may be helpful to Implement a reasonable routine QA of the OBI isocenter accuracy without great efforts.

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Correlation between Glycemic Index and in vitro Starch Hydrolysis of Cereals (곡류의 혈당지수와 전분 가수분해율과의 상관관계)

  • Lee, Jung-Sun;Shin, Hyun-Kyung
    • Korean Journal of Food Science and Technology
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    • v.30 no.5
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    • pp.1229-1235
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    • 1998
  • To see the correlation between the rate of in vitro starch hydrolysis and the glycemic index, an in vitro digestion was carried out by incubating the cereal samples for 2 hours with ${\alpha}-amylase$ in dialysis tubing. Also the levels of blood glucose were measured over 2 hours after feeding healthy volunteers with 50 g carbohydrate portions. Hydrolysis area, hydrolysis index (HI) and the dialysate content of carbohydrate throughout the digestion time for barley was significantly below those for other cereals (p<0.05), and unpolished glutinous rice was significantly above (p<0.05). The GI-glucose of barley $(57%{\pm}7)$ to glucose as standard was significantly (p<0.05) lower than those of other cereals whereas the GI-glucose of glutinous rice $(110%{\pm}8)$ was significantly higher (p<0.05) than other cereals. The GI-rice values to rice as standard were $122%{\pm}4$ for glutinous sorghum, $116%{\pm}13$ for job's tear, $115%{\pm}13$ for glutinous millet, $106%{\pm}6$ for unpolished glutinous rice, $102%{\pm}7$ for glutinous rice, $100%{\pm}0$ for rice, $90%{\pm}12$ for unpolished rice, $85%{\pm}6$ for foxtail millet, $79%{\pm}5$ for buckwheat and $63%{\pm}6$ for barley. The GI-rice was significantly correlated to hydrolysis area and HI (r=0.75, p<0.01). It suggests that the in vitro starch hydrolysis offers good potential to predict the in vivo glycemic response of starch foods.

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Preparation and Characterization of $Cu/Ce_xZr_{1-x}O_2$ Catalysts for Preferential Oxidation of Carbon Monoxide (일산화탄소의 선택적 산화반응을 위한 $Cu/Ce_xZr_{1-x}O_2$ 촉매의 합성과 특성분석)

  • Lee, So-Yeon;Lee, Suk-Hee;Cheon, Jae-Kee;Woo, Hee-Chul
    • Clean Technology
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    • v.13 no.1 s.36
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    • pp.54-63
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    • 2007
  • Even traces of CO in the hydrogen-rich feed gas to proton exchange membrane fuel cells (PEMFC) poison the platinum anode electrode and dramatically decrease the power output. In this work, a variety of catalytic materials consisting of $Cu/Ce_xZr_{1-x}O_2$, (x = 0.0-1.0) were synthesised, characterized and tested for CO oxidation and preferential oxidation of CO (PROX). These catalysts prepared by hydrothermal and deposition-precipitation methods. The catalysts were characterized by XRD, XRF, SEM, BET, $N_2O$ titration and oxygen storage capacity (OSC) measurement. The effects of composition of the support and degree of excess oxygen were investigated fur activity and $CO_2$ selectivity with different temperatures. The composition of the support markedly influenced the PROX activity. Among the various $Cu/Ce_xZr_{1-x}O_2$ catalysts having different composition, $Cu/Ce_{0.9}Zr_{0.1}O_2$ and $Cu/Ce_{0.7}Zr_{0.3}O_2$ showed the highest activities (>99%) and selectivities (ca.50%) in the temperature range of $150{\sim}160^{\circ}C$. It was found that by using of $Ce_xZr_{1-x}O_2$ mixed oxide support which possesses a high oxygen storage capacity, oxidation-reduction activity of Cu-based catalyst was improved, which resulted in the increase of catalytic activity and selectivity of CO oxidation in excess $H_2$ environments.

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Multinational Corporate Linkage Stability in the Canadian Urban System (캐나다 도시체계에서의 다국적기업 연계패턴의 안정성)

  • Kee-Bom Nahm
    • Journal of the Economic Geographical Society of Korea
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    • v.1 no.1
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    • pp.151-172
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    • 1998
  • Over the past two decades, the process of globalization of multinational corporations has increased at a rapid rate. One manifestation of this process is the establishment of corporate head offices in a variety of international centers to administer and coordinate, the day-to-day operations in the host countries. In establishing a subsidiary overseas a firm creates a direct link between the operations of the domestic corporate center and the foreign host center This paper investigates elements of stability and change in the international linkage patterns among domestic parent corporations and host subsidiaries over the past several decades. In particular, it seeks answers to a number of question related to stability and change in linkages among foreign centers of control and those Canadian centers selected to administer the subsidiary operations from 1970 to 1991 over the four primary sectors, namely, resources, manufacturing, services, and finance. By confirming the core stability and dispersed linkages hypotheses, the papar offers some generalizations with respect to the location and stability of subsidiary headquarters centers in Canada and their respective subsector specialties. Finally, it addresses further research avenues fer the quaternary place study.

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Effects of γ-Irradiation from Cobalt-60 on Immunogenicity of Eimeria tenella (Cobalt-60 γ-선 조사가 Eimeria tenella 의 면역원성에 미치는 영향)

  • Youn, Hee-jeong;Kang, Yung-bai;Jang, Du-hwan
    • Korean Journal of Veterinary Research
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    • v.33 no.4
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    • pp.657-664
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    • 1993
  • To reveal the immunogenicity of ${\gamma}-irradiated$ E tenella and its progeny, a series of experiments on the effects of Cobalt-to ${\gamma}-irradiation$ was performed. The SPF chickens inoculated with diffenrt doses of inoculum were challenged with $1{\times}10^5$ oocysts of virulent E tenella. The levels of 100 Gy ${\gamma}-irradiation$ from $^{60}Co$ and of inoculum with $1{\times}10^4$ oocysts were recognized as proper as immunogen by comparison of survival rates, body weight gains, blood in feces and lesion scores in the chickens. In these trials of challenge with virulent E tenella after inoculation with $1{\times}10^4$ oocysts of the ${\gamma}-irradiated$ E tenella and its progeny, the survival rates of the chickens challenged with the virulent E tenella after immunization with the 1st and the 3rd progeny groups of ${\gamma}-irradiated$ E tenella oocysts were higher(l00%) than that(87.0%) of the challenged control group. The signs of blood in feces and the lesion scores were seen markedly lower with the ourput of the smaller number of oocysts, i.e. OPG 103,900 and 25,800 in the groups of the 1st and the 3rd progeny, respectively, than those(OPG 1,658,900) of the challenged control group. The body weight gains of the 1st and the 3rd progeny groups, the 1st week and the 2nd week after challenge, were higher (2.6g and 155.4g, 11.6g and 168.9g respectively) than those(-85.8g and 63.6g, respectively) of the challenged control group, and the feed conversion ratios(FCR 3.28 and 2.96) of the 1st and the 3rd progeny groups were lower than that(FCR 5.60) of the groups challenged control group. The anticoccidial indices(70.5 and 93.9) of the groups challenged with the virulent oocysts of E tenella after immunization with the 1st and the 3rd progeny of the ${\gamma}-irradiated$ E tenella were significantly higher than that (ACI -81.9) of the challenged control group. It was thought that the immunogenicity of ${\gamma}-irradiated$ E tenella would be increase according to increase the number of generation passaged in chicken. That might be because of increasing the pathogenicity of ${\gamma}-irradiated$ E tenella according to increase the number of generation passaged in chicken.

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Oxidative Desulfurization of Marine Diesel Using Keggin Type Heteropoly Acid Catalysts (Keggin형 헤테로폴리산 촉매를 이용한 선박용 경유의 산화 탈황)

  • Oh, Hyeonwoo;Woo, Hee Chul
    • Clean Technology
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    • v.25 no.1
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    • pp.91-97
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    • 2019
  • Oxidative desulfurization (ODS) has received much attention in recent years because refractory sulfur compounds such as dibenzothiophenes can be oxidized selectively to their corresponding sulfoxides and sulfones, and these products can be removed by extraction and adsorption. In this work, The oxidative desulfurization of marine diesel fuel was performed in a batch reactor with hydrogen peroxide ($H_2O_2$) in the presence of various supported heteropoly acid catalysts. The catalysts were characterized by XRD, XRF, XPS and nitrogen adsorption isotherm techniques. Based on the sulfur removal efficiency of promising silica supported heteropoly acid catalysts, the ranking of catalytic activity was: $30\;H_3PW_{12}/SiO_2$ > $30\;H_3PMo_{12}/SiO_2$ > $30\;H_4SiW_{12}/SiO_2$, which appears to be related with their intrinsic acid strength. The $30\;H_3PW_{12}/SiO_2$ catalyst showed the highest initial sulfur removal efficiency of about 66% under reaction conditions of $30^{\circ}C$, $0.025g\;mL^{-1}$ (cat./oil), 1 h reaction time. However, through the recycle test of the $H_3PW_{12}/SiO_2$ catalyst, significant deactivation was observed, which was attributed to the elution of the active component $H_3PW_{12}$. By introducing cesium cation ($Cs^+$) into the $H_3PW_{12}/SiO_2$ catalyst, the stability of the catalyst was improved with changing the solubility, and the $Cs^+$ ion exchanged catalyst could be recycled for at least five times without severe elution.

Screening of cryoprotectants (CPAs) for cryopreservation in the Nitzschia sp. of marine microalgae (해양 규조류 Nitzschia sp.의 초저온동결보존을 위한 보존제의 영향 분석)

  • Lee, In Hye;Jeon, Ji Young;Kim, Kyeung Mi;Kang, Myung suk
    • Journal of Plant Biotechnology
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    • v.45 no.4
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    • pp.400-408
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    • 2018
  • Biodiversity has continued to degrade in the $21^{st}$ century due to global warming occasioned by destruction of the environment around the world.. The Nagoya protocol places Korea in a unique position to effectively develop and protect its domestic genetic resources. Microalgae under study in this research contains large amount of antioxidant substances such as beta carotene and astaxanthin, that can be used as biological resource owing to the large amounts of biomass that can be secured through photosynthesis. However, it is difficult to preserve it since cryopreservation method used for long-term preservation is yet to be developed. A basic study for long term cryopreservation was carried out on Nizschia frustulum and Nitzschia amabilis which belong to marine diatoms. As cryoprotectants (CPAs), glycerol, DMSO, and methanol which penetrate into cells were prepared at 5%, 10%, and 15% concentrations each, in case of methanol, it was tested at concentrations of 5%, 10% and 12% by its nature. Two kinds of microalgae, N. frustulum and N. amabilis, were diluted with $10^2$, $10^3$ and $10^4cells\;ml^{-1}$, respectively. The highest survival rate was shown at12% concentration of methanol, and the figures were $6.94{\pm}0.31%$ in N. frustulum and $8.85{\pm}0.16%$ in N. amabilis. As a result of 3 weeks cultivation of thawed microalgae after freezing, the result is shows that N. frustulum increased about 10 times faster and N. amabilis increased about 12 times the original concentration.

Water Digital Twin for High-tech Electronics Industrial Wastewater Treatment System (II): e-ASM Calibration, Effluent Prediction, Process selection, and Design (첨단 전자산업 폐수처리시설의 Water Digital Twin(II): e-ASM 모델 보정, 수질 예측, 공정 선택과 설계)

  • Heo, SungKu;Jeong, Chanhyeok;Lee, Nahui;Shim, Yerim;Woo, TaeYong;Kim, JeongIn;Yoo, ChangKyoo
    • Clean Technology
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    • v.28 no.1
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    • pp.79-93
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    • 2022
  • In this study, an electronics industrial wastewater activated sludge model (e-ASM) to be used as a Water Digital Twin was calibrated based on real high-tech electronics industrial wastewater treatment measurements from lab-scale and pilot-scale reactors, and examined for its treatment performance, effluent quality prediction, and optimal process selection. For specialized modeling of a high-tech electronics industrial wastewater treatment system, the kinetic parameters of the e-ASM were identified by a sensitivity analysis and calibrated by the multiple response surface method (MRS). The calibrated e-ASM showed a high compatibility of more than 90% with the experimental data from the lab-scale and pilot-scale processes. Four electronics industrial wastewater treatment processes-MLE, A2/O, 4-stage MLE-MBR, and Bardenpo-MBR-were implemented with the proposed Water Digital Twin to compare their removal efficiencies according to various electronics industrial wastewater characteristics. Bardenpo-MBR stably removed more than 90% of the chemical oxygen demand (COD) and showed the highest nitrogen removal efficiency. Furthermore, a high concentration of 1,800 mg L-1 T MAH influent could be 98% removed when the HRT of the Bardenpho-MBR process was more than 3 days. Hence, it is expected that the e-ASM in this study can be used as a Water Digital Twin platform with high compatibility in a variety of situations, including plant optimization, Water AI, and the selection of best available technology (BAT) for a sustainable high-tech electronics industry.

Application of Deep Learning for Classification of Ancient Korean Roof-end Tile Images (딥러닝을 활용한 고대 수막새 이미지 분류 검토)

  • KIM Younghyun
    • Korean Journal of Heritage: History & Science
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    • v.57 no.3
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    • pp.24-35
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    • 2024
  • Recently, research using deep learning technologies such as artificial intelligence, convolutional neural networks, etc. has been actively conducted in various fields including healthcare, manufacturing, autonomous driving, and security, and is having a significant influence on society. In line with this trend, the present study attempted to apply deep learning to the classification of archaeological artifacts, specifically ancient Korean roof-end tiles. Using 100 images of roof-end tiles from each of the Goguryeo, Baekje, and Silla dynasties, for a total of 300 base images, a dataset was formed and expanded to 1,200 images using data augmentation techniques. After building a model using transfer learning from the pre-trained EfficientNetB0 model and conducting five-fold cross-validation, an average training accuracy of 98.06% and validation accuracy of 97.08% were achieved. Furthermore, when model performance was evaluated with a test dataset of 240 images, it could classify the roof-end tile images from the three dynasties with a minimum accuracy of 91%. In particular, with a learning rate of 0.0001, the model exhibited the highest performance, with accuracy of 92.92%, precision of 92.96%, recall of 92.92%, and F1 score of 92.93%. This optimal result was obtained by preventing overfitting and underfitting issues using various learning rate settings and finding the optimal hyperparameters. The study's findings confirm the potential for applying deep learning technologies to the classification of Korean archaeological materials, which is significant. Additionally, it was confirmed that the existing ImageNet dataset and parameters could be positively applied to the analysis of archaeological data. This approach could lead to the creation of various models for future archaeological database accumulation, the use of artifacts in museums, and classification and organization of artifacts.