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Determination and application of installation sequence of piping systems in cramped spaces of ships and offshore structures considering geometric relationship of pipe elements

  • Jang, MiSeon;Nam, Jong-Ho
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.12 no.1
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    • pp.60-70
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    • 2020
  • The outfitting design of ships and offshore structures is mainly undertaken in a restricted space. Pipes occupying a large portion of outfitting design are normally manufactured outside the shipyard. This complicated manufacturing process results in frequent delivery delays. Inevitable design modifications and material changes have also resulted in inefficient pipe installation works. In this study, an algorithm is proposed to systematically determine the pipe installation sequence. An accurate and fast algorithm to identify the geometric relationship of piping materials is presented. To improve the calculation efficiency, the interference is gradually examined from simplified to complicated shapes. It is demonstrated that the calculation efficiency is significantly improved with successive geometric operations such as back-face culling and use of bounding boxes. After the final installation sequence is determined, the entire installation process is visualized in a virtual reality environment so that the process can be rendered and understood for a full-scale model.

Comparison of Anti-oxidative Activity in a Single Serving Size of the Commercial Coffees and Teas

  • Kim, Tae-Hun;Lee, Seulgi;Seo, Jin Woo;Bing, Sun Hye;Kim, Jong Im;Kwon, Eui-Ra;Jo, Gune-Hee;Lee, Jae-Myean;Choi, Joon Sig
    • Journal of Food Hygiene and Safety
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    • v.32 no.6
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    • pp.460-469
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    • 2017
  • The aim of this work was to study the comparison of anti-oxidative activity in a single serving size of commercial coffees and teas. Commercial regular coffees and teas, including, brand regular coffees ($BC_A$, $BC_B$, $BC_C$, $BC_D$, and $BC_E$), green tea ($GT_A$, $GT_B$, $GT_C$, and $GT_D$), black tea ($BT_A$, $BT_B$, and $BT_C$), pu-erh tea ($PT_A$, $PT_B$, and $PT_C$), chamomile tea ($CT_A$, $CT_B$, and $CT_C$), peppermint tea ($P_A$, $P_B$, and $P_C$), polygonatum odoratum tea ($POT_A$, $POT_B$, and $POT_C$), and jujube tea ($JT_A$, $JT_B$, and $JT_C$) were assayed for the levels of ascorbic acid, caffeine, total content of polyphenols and flavonoids, and ability to scavenge free radicals, using two in vitro antioxidant assays. The scavenging abilities of $BC_A$ and $BC_C$ were $664.91{\pm}48.87mg$ ascorbic acid equivalent/serving size and $624.36{\pm}16.18mg$ ascorbic acid equivalent/serving size, respectively. The four beverage samples ($BC_A$, $BC_C$, $GT_D$, and $BT_A$) significantly reduced the production of reactive oxygen species (ROS) and intracellular oxidative stress induced by $H_2O_2$. These results suggest that the beverages possess significant radical scavenging ability, which may be due to the presence of antioxidants. Furthermore, the significant reducing level of ROS evidences the potential antioxidant effects of these beverages in human cells.

Identification of Cultivate Sites for Job's-tears (Coix lachrymajobi var. mayuen) using Capillary Electrophoresis (Capillary electrophoresis를 이용한 율무의 원산지 판별)

  • Rhyu, Mee-Ra;Kim, Eun-Young;Kim, Sang-Sook
    • Korean Journal of Food Science and Technology
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    • v.34 no.5
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    • pp.787-791
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    • 2002
  • Optimal extraction, separation, and capillary rinsing conditions for capillary electrophoresis (CE) were established to identify the cultivation site (domestic vs. foreign) of Job's-tears (Coix lachrymajobi var. mayuen) using 240 samples (domestic sample n = 121, foreign sample n = 119). Job's-tears was extracted with 30% ethanol and separated on a $50-{\mu}m-I.D.$ untreated fused-silica capillary. Optimal analytic conditions were: temperature, $45^{\circ}C$; voltage, 15 kV; detector rise time, 0.1 sec; and pressure injection, 20 sec. Separation of peak investigated using 0.1 M phosphate buffer (pH 2.5) containing 0.05% hydroxypropylmethylcellulose (P buffer) revealed the optimal separation buffer was P buffer containing 26 mM hexane sulfonic acid with 30% methanol. Under the optimal conditions established for CE, the average correct identification percentage of domestic or foreign Job's-tears was 82%.

Development of Satisfaction Evaluation Items for Degree-linked High Skills Meister Courses using the Delphi Method (Delphi 기법을 활용한 학위연계형 고숙련마이스터 과정의 만족도 평가 문항 개발)

  • Kim, Seung-Hee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.20 no.5
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    • pp.163-173
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    • 2020
  • In this study, on-site corporate instructors participated as student-cum-workers in a degree-linked high skills Meister course to improve job competency and practical ability as proposed in the Work-Study Career Vision. Evaluation questions were then developed and their validity was verified by assessing satisfaction related to expected goals in enhancing advanced training guidance and competency as an evaluator. Satisfaction assessment was conducted based on training preparation, training implementation, training effectiveness and training administration. The Delphi Method was adopted and a total of 48 items were developed in 6 categories under 4 main areas. There were 7 evaluation items on the satisfaction of training course development under training preparation, 21 evaluation items related to the satisfaction of Off-JT and OJT courses under training implementation, 16 evaluation items related to the satisfaction of increased competency as an on-site corporate instructor and the satisfaction of enhanced practical skills and skills application at work under training effectiveness, as well as 6 evaluation items to assess satisfaction with administrative support under training administration. The final conformity assessment was conducted based on the stability, content validity ratio, consensus and convergence indicators of the developed items. Results of this study do not only apply to quality management of the high skills Meister course which is being promoted as a pilot project for work-study programs, but also serves as a rationale that may be considered as a basic research tool in the collection of various opinions to derive overall system improvement factors for the work-study high skills Meister course.

A Study of Analysis Current state of the Apprenticeship Curriculum in Vocational Education and Training High Schools Participating in the Apprenticeship System (산학일체형 도제학교의 도제 교육과정 편성 현황 분석 연구)

  • Ahn, Jae-Yeong
    • Journal of vocational education research
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    • v.36 no.4
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    • pp.57-78
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    • 2017
  • This study aimed to make proposals to develop an apprenticeship program and organize the apprenticeship curriculum by conducting an overall analysis of how vocational education and training high schools participating in the apprenticeship system(apprenticeship schools) organized the apprenticeship program in the school curriculum. To that end, the study analyzed the current state of the apprenticeship curriculum of 33 apprenticeship schools and came up with the following results: First, the apprenticeship class and the general class had a similar relevance between 'departments' and 'areas and goals of student training' and between 'departments' and 'qualifications,' while the apprenticeship class had a higher relevance between 'areas and goals of student training' and 'qualifications' than the general class. Second, both the required and optional competency units of the apprenticeship program were relatively evenly included in the Off-JT and OJT. Third, the competency units of the apprentice program were included in the technical subjects of the 2009 revised curriculum as well as the NCS practical subjects of the 2015 revised curriculum. Fourth, although most of the competency units of the apprenticeship program have a high correlation with the technical subjects of the school curriculum, there were also many schools showing a low correlation. Fifth, although the hierarchy of organizing the competency units of the apprenticeship program by semester was mostly high, there were a considerable number of schools with a low hierarchy. As a result, this study made the following policy proposals: granting a grace period for approval of the changes in the curriculum of the apprenticeship, distributing the matching table before and after the revision of the NCS competency units, organizing subjects not included in the national curriculum, creating subjects specialized for companies, and monitoring and consulting the curriculum of the apprenticeship schools.

A Study on New Train Control System of the SMRT(Seoul Metropolitan Rapid Transit Corporation) (서울도시철도 신 열차제어시스템에 대한 연구)

  • Yu, Guen-Gyu;Park, Jong-Hun;Ahn, Jin-Seong;Kim, Ki-Chun;Lee, Sang-Guen
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.895-903
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    • 2011
  • The Seoul Metropolitan Rapid Transit Corporation(SMRT) is studying the New Train Control System based on Wireless Communication(CBTC System : Communication Based Train Control System) to overcome the limitations of the existing system and to deal with the switch to the new system. The SMRT's New Train Control System Based on three main elements(train position detecting, radio communication and train control) is being developed in 3 stages. Currently, the development of the train position detecting element with the RFID system and the train position detecting device and the radio communication element with RTIS and DSRC had been developed and equipped on 3 stations(Songpa~Garak Market~Munjeong, 7.3km) of Subway Line 8 in the pilot. Such a basic infrastructure of the SMRT's New Train Control System is having an efficiency test by using the real-time Train Monitoring System and Currently, the third element, the train control(ATP/ATO/ATS/Interlocking) for the study is in progress. Also, the developed system is expected to validate the performance and safety in the next three stage. This paper shows about major developments of the SMRT's New Train Control System and our future plans.

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A Study on the Properties of Azo Disperse Dyes Containing Ethyleneimine Derivatives (III) - Application to Microfibre Polyester and Nylon 6.6 Fabrics - (에틸렌이민 유도체를 갖는 아조계 분산염료의 염색성에 관한 연구(III) - 폴리에스테르 및 나일론 6.6 극세사 섬유에의 응용 -)

  • Sunwoo, Kong Hyun;Burkinshaw, S M
    • Textile Coloration and Finishing
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    • v.8 no.6
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    • pp.9-26
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    • 1996
  • 이 연구의 목적은 에틸렌이민 유도체를 갖는 아조계 분산 염료의 나일론 6.6 섬유에의 응용과 최적화된 폴리에스테르 및 나이론 극세사 섬유 염색 조건의 확립이다. 세가지 아지리디닐 모노 아조 염료와 이들 염료의 가수분해 된 형태 그리고 디메틸아닐린계 아조 염료의 폴리에스테르 및 나일론 6.6 극세사 섬유에 대한 염색 및 견뢰도 성질이 조사되었다. 염색 조건 중 pH의 변화에 따른 섬유상의 염착량 변화 조사에서 뚜렷한 경향을 얻을 수 없었으며, 이는 극세사 섬유의 물리적 성질이 두드러지게 착용한 이유라 여겨진다. 염색된 폴리에스테르 극세사 섬유상에서, 아지리디닐 염료는 이들의 가수 분해된 형태 그리고 디메틸아닐린계 아조 염료의 비교하여 개선된 견뢰도 성질을 나타내었다. 아지리디닐 아조 염료의 나일론 극세사 섬유 염색 시 pH 증가에 따라 세탁 및 광견뢰도가 개선되었고, pH8의 염색 조건에서 최적 견뢰도 개선을 나타내었다. 아지리디닐 아조 염료가 이들 염료의 가수분해 된 형태 그리고 디메틸아닐린계 아조 염료와 비교하여 폴리에스테르 및 나일론 섬유상에서 보다 개선된 견뢰도 성질을 나타내었고 이는 섬유와 염료간의 공유 결합으로 기인한 것으로 여겨진다.

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Real-Time Haptic Rendering for Multi-contact Interaction with Virtual Environment (가상현실을 위한 다중 접촉 실시간 햅틱 랜더링)

  • Lee, Kyung-No;Lee, Doo-Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.7
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    • pp.663-671
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    • 2008
  • This paper presents a real-time haptic rendering method for multi-contact interaction with virtual environments. Haptic systems often employ physics-based deformation models such as finite-element models and mass-spring models which demand heavy computational overhead. The haptic system can be designed to have two sampling times, T and JT, for the haptic loop and the graphic loop, respectively. A multi-rate output-estimation with an exponential forgetting factor is proposed to implement real-time haptic rendering for the haptic systems with two sampling rates. The computational burden of the output-estimation increases rapidly as the number of contact points increases. To reduce the computation of the estimation, the multi-rate output-estimation with reduced parameters is developed in this paper. Performance of the new output-estimation with reduced parameters is compared with the original output-estimation with full parameters and an exponential forgetting factor. Estimated outputs are computed from the estimated input-output model at a high rate, and trace the analytical outputs computed from the deformation model. The performance is demonstrated by simulation with a linear tensor-mass model.

Pregnancy and Delivery by Round Spermatid Injection into Oocytes in Human (원형정자세포의 주입에 의한 임신과 분만 1례)

  • Lee, S.M.;Jung, J.Y.;Han, Y.T.;Park, H.T.;Park, H.D.;Chung, K.S.;Lee, K.Y.
    • Clinical and Experimental Reproductive Medicine
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    • v.25 no.2
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    • pp.233-237
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    • 1998
  • We demonstrated that the normal pregnancy and delivery by round spermatid injection (ROSI) into oocytes was achieved from nonobstructive azoospermia patient. In this case, the normal fertilization rate was 50%. All of the two pronuclear stage embryos cleaved and were transferred to the patient's uterus. A singleton pregnancy was achieved and resulted in the birth of normal female infant. This resuJt show that intracytoplasraic injection of round spermatid seems to be new treatment of nonobstmctive azoospermia male infertility. Further research is needed to evaluate the required culture conditions to induce progression of the round spermatid into a more elongated stage.

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Prediction of liquid amount in hydrogen liquefaction systems using GM refrigerator (GM냉동기를 이용한 수소액화 시스템의 액화량 예측)

  • 박대종;장호명;강병하
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.11 no.3
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    • pp.349-358
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    • 1999
  • Thermodynamic cycle analysis has been performed to maximize the liquid amount for various hydrogen liquefaction systems using GM(Gifford-McMahon) refrigerator. Since the present authors' previous experiments showed that the liquefaction rate was approximately 5.1mg/s in a direct contact with a commercial GM refrigerator, the purpose of this study is to predict how much the liquefaction rate can be increased in different configurations and with improved heat exchanger performance. The optimal operating conditions have been analytically sought with real properties of normal hydrogen for the single-stage GM precooled L-H(Linde-Hampson) system, the two-stage GM direct contact system, the two-stage GM precooled L-H system and the two-stage helium GM-JT (Joule-Thomson) system. The maximum liquefaction rate has been predicted to be only about 7 times greater than the previous experiment, when the two-stage precooling is employed and the effectiveness of heat exchangers approaches to 99.0%. It is concluded that the liquefaction rate is limited mainly by the cooling capacity of the current GM refrigerators and a larger scale of hydrogen liquefaction is possible with a greater capacity of cryocooler at 60-70 K range.

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