• Journal of the Korean Society for Nondestructive Testing
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• v.20 no.5
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• pp.451-456
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• 2000

The development of an integrated technology including fabrication of corrosion defect specimens and their practical use is needed to enhance the reliability of eddy current test for nuclear steam generator tubing. In this paper, the necessity and importance are presented from the viewpoint of the structural integrity, simulation specimens for real defects, and experiences from the destructive examination of pulled tubes. The models for several corrosion defects we also briefly introduced, with the scheme for their practical use.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.221-228
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• 2005

The intent of this study is to investigate whether two oriental medical prescriptions named haengsotang(HST) and gami-palmihwan(GPMH) significantly effect mucin release from cultured hamster tracheal surface epithelial(HTSE) cells, Confluent HTSE cells were metabolically radiolabeled with $^3H-glucosamine$ for 24 hrs and chased for 30 min in the presence of HST or GPMH to assess the effect of each agent on $^3H-mucin$ release. Possible cytotoxicities of each agent were assessed by measuring lactate dehydrogenase(LDH) release. Also, the effects of HST and GPMH on contractility of isolated tracheal smooth muscle were investigated. The results are consistant with the following assertions: (1) HST significantly inhibited mucin release from cultured HTSE cells, without cytotoxicity; (2) GPMH did not effect mucin release without cytotoxicity; (3) HST and GPMH did not effect contractility of isolated tracheal smooth muscle. These results suggest a need for further investigation of HST and its components, for its potential in oriental medicine prescriptions and novel agents that effectively regulate (inhibit) mucin secretion from airway goblet cells.

• Applied Chemistry for Engineering
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• v.7 no.3
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• pp.573-579
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• 1996

Effects of operating variables on the conversion of the formation reaction of meta boric acid from ortho boric acid in a laboratory-scale bubble column reactor were investigated to obtain the basic data which are indispensable for the design, scale-up, control, development and operation of industrial bubble column reactors. Reaction time and pressure, particle size of reactant and gas flow rate were chosen as experimental variables. Effects of the experimental variables on the gas holdup in the bubble column reactor were also discussed in relation to the conversion of reaction. From the results of this study, the optimum conditions were drawn as follows : Reaction time ; 35~40(min), reaction pressure ; 92~95(kPa), particle size ; under $0.6{\times}10^{-3}(m)$, gas flow rate ; 0.07~0.08(m/s).

• Journal of Korea Foundry Society
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• v.20 no.4
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• pp.254-259
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• 2000

Metal matrix composites(MMCs) reinforced with hard particles have many potential application in aerospace structures, auto parts, semiconductor package, heat resistant panels, wear resistant materials and so on. In this work, the effect of SiC partioel sizes(50 and 100 ${\mu}m$) and additional elements such as Si, Cu and Ti on the microstructure and the wear property of $Al-5Mg-X(Si,Cu,Ti)/SiC_p$ composites produced by pressureless infiltration method have been investigated using optical microscopy, scanning eletron microcopy(SEM) with EDS(energy dispersive spectrometry), hardness test, X-ray diffractometer(XRD) and wear test. In present study, the sound $Al-5Mg-X(Si,Cu,Ti)/SiC_p$(50 and 100 ${\mu}m$) composites were fabricated by pressureless infiltration method. The $Al-5Mg-0.3Si-O.1Cu-O.1Ti/SiC_p$ composite with $50 {\mu}m$ size of SiC particle has higher hardness and better wear property than any other composite with $100{\mu}m$ size of SiC particle produced by pressureless infiltration method. The hardness and wear property of $Al-5Mg/SiC_p$(50 and 100 ${\mu}m$) composites were enhanced by the addition of Si, Cu and Ti in Al-5%Mg matrix alloy.

• Advances in Traditional Medicine
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• v.4 no.1
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• pp.18-21
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• 2004

Six volunteers (mean $age=25.7{\pm}1.7$, $height=173{\pm}1.9$ and $weight=63.4{\pm}2.3{\;}kg$) participated in a graded exercise test and one hour of basic form of ChunDoSunBup (CDSB) Qi-training to investigate the cardiorespiratory responses and exercise intensity of Qi-training, a Korean traditional psychosomatic training. In the maximal exercise, the trainee showed $96.2{\pm}8.89{\;}l/min$ in ventilation (VE), $46.0{\pm}4.4$ in breath frequency (BF), $1.31{\pm}0.05$ in respiratory exchange ratio (RER), $180.7{\pm}3.0$ in heart rate (HR), and $2.6{\pm}1.1{\;}l/min$ or $40.7{\pm}2.3{\;}ml/kg/ml$ in oxygen consumption $(VO_2)$. Qi-training induced significant changes in BF, RER, HR, and $VO_2$. The exercise intensity of Qi-training were 42.3%, 46.9% and 38.7% of $HR_{max}$ during the sound exercise, slow motion (haeng-gong) and meditation respectively and the average was 46.2% of $HR_{max}$. We conclude that Qi-training is an aerobic exercise of a light (mild) intensity exercise, and it leads to decrease the metabolic rate in the trainee by breathing efficiently and relaxing them. In addition, Qi-training may affect cardiorespiratory function of BF, RER, HR and $VO_{2max}$ in trainees.

• Journal of the Korean Institute of Intelligent Systems
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• v.17 no.3
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• pp.410-416
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• 2007

There are many demands for interoperability between weapon systems as the operational needs for joint and coalition based on network in modern and future warfare have been increasingly needed. In DoD, LISI has been applied throughout information system life cycle from the planning phase to the development phase to assess the level of interoperability. We also developed SITES which is a tool to assess the level of interoperability in information systems. But we should extend the assessment model from the previous information systems to the weapon systems to assess the level of interoperability including weapon systems as well as information systems. In this paper, we proposed the assessment model of interoperability, implemented the E-SITE based on the proposed model, applied 12 weapon systems and analyzed the experimental result.

• YAKHAK HOEJI
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• v.55 no.4
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• pp.338-344
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• 2011

This study aimed to identify the changes in the list of drugs covered by national health insurance(NHI) after the introduction of positive list system (PLS) in Korea in December, 2006. Six-year (pre-policy:2004-2006, post-policy:2007-2009) lists of the NHI reimbursable drugs filed from Health Insurance Review and Assessment Service (HIRA) were analyzed. The total number of listed drugs as well as drug ingredients, and the average number of listed drugs per manufacturer decreased annually after the introduction of PLS. More than 8,000 drugs were delisted in the year 2007 right after the policy change. Prescription-only drugs occupied more than 85% of NHI listed drugs. The percentage of oral type of listed drugs has been increased to more than 60% after the policy change. Korean pharmaceutical manufacturers occupied more than 90% of listed drugs than multinational firms. The gap between Korean and foreign manufacturer in terms of the average number of newly listed drugs per manufacturer in each year has decreased two years after the PLS (Korean 7.7 vs. foreign 6.3 in 2009) as the price negotiation power of foreign firms has increased. The total number of listed drugs is expected to decrease in the future as the Korean government makes an effort to delist the unnecessary drugs that do not show cost-effectiveness.

• Journal of the Ergonomics Society of Korea
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• v.27 no.4
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• pp.15-26
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• 2008

Recently, Internet Protocol TV technology has a latent power for searching information by using internet-connected interactive TV media. It is hard to browse and search web site conveniently since the visual and input devices are not sufficient for navigating through the websites. Zoomable user interface is a possible solution that may reduce users' task load and improve their performance. In this paper, we made three types of web browsers as scroll, physical zooming and semantic zooming type. Fifteen participants asked to do searching tasks and their task time, accuracy and subjective responses are recorded. In the result, though scroll type is evaluated more efficient than other types in task time and accuracy since participants are familiar with scroll type interface, semantic zooming type is highly rated in subjective responses such as perceived searching efficiency, satisfaction and joyfulness. This result implied semantic zooming is a possible solution which is improving user experience of searching websites using Internet Protocol TV.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.4 s.304
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• pp.133-142
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• 2005

In this paper, two digital video scrambling methods are proposed as simple means of the digital content protection techniques. One is inter block scrambling using motion vector, the other is intra block scrambling using intra prediction mode. The proposed inter block scrambling method distorts the original sequences by swapping horizontal and vertical components of motion vector. This method can be applied on most common video coding techniques such as MPEG-1, 2, 4, H.264, etc. The proposed intra block scrambling method distorts the original sequences by modifying intra prediction mode that is property of H.254 video coding technique. Both methods do not cause my bit rate increase after scrambling. Moreover, they have low complexity because they need only simple operation like XOR. Especially, the proposed intra block scrambling does not distort inter blocks directly. But inter blocks are distorted by error propagation effect as much as intra blocks. This paper introduces two new digital video scrambling method and verifies its effectiveness through simulation.

• Aerospace Engineering and Technology
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• v.9 no.1
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• pp.28-34
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• 2010

All pixels of image sensor do not react uniformly when the light of same radiance enters into the camera. This non-uniformity has a direct influence on the image quality. However we can overcome it by calibration process under the special test-setup. Usually it is used the algorithm to get the correction coefficients under the specific illumination condition. But, this method has drawback in the very low or very high illumination due to pixel non-linearity. This paper describes the robust algorithm, which calculates the correction coefficients based on the pixel non-linearity model, against thew hole radiance. The paper shows the non-uniformity test results with the own camera and the specified test equipments as well. The results shows the best performance over the entire radiance when this method is applied.