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A Study on Real-Time Defect Detection Using Ultrasound Excited Thermography (초음파 서모그라피를 이용한 실시간 결함 검출에 대한 연구)

  • Cho, Jai-Wan;Seo, Yong-Chil;Jung, Seung-Ho;Jung, Hyun-Kyu;Kim, Seung-Ho
    • Journal of the Korean Society for Nondestructive Testing
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    • v.26 no.4
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    • pp.211-219
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    • 2006
  • The UET(ultrasound excited thermography) for the ,eat-time diagnostics of the object employs an infrared camera to image defects of the surface and subsurface which are locally heated using high-frequency putted ultrasonic excitation. The dissipation of high-power ultrasonic energy around the feces of the defects causes an increase In temperature. The defect's image appears as a hot spot (bright IR source) within a dark background field. The UET for nondestructive diagnostic and evaluation is based on the image analysis of the hot spot as a local response to ultrasonic excited heat deposition. In this paper the applicability of VET for fast imaging of defect is described. The ultrasonic energy is injected into the sample through a transducer in the vertical and horizontal directions respectively. The voltage applied to the transducer is measured by digital oscilloscope, and the waveform are compared. Measurements were performed on four kinds of materials: SUS fatigue crack specimen(thickness 14mm), PCB plate(1.8 mm), CFRP plate(3 mm) and Inconel 600 plate (1 mm). A high power ultrasonic energy with pulse durations of 250ms Is injected into the samples in the horizontal and vertical directions respectively The obtained experimental result reveals that the dissipation loss of the ultrasonic energy In the vertical injection is less than that in the horizontal direction. In the cafe or PCB, CFRP, the size of hot spot in the vortical injection if larger than that in horizontal direction. Duration time of the hot spot in the vertical direction is three times as long as that in the horizontal direction. In the case of Inconel 600 plate and SUS sample, the hot spot in the horizontal injection was detected faster than that in the vertical direction

Characteristics of the Differences between Significant Wave Height at Ieodo Ocean Research Station and Satellite Altimeter-measured Data over a Decade (2004~2016) (이어도 해양과학기지 관측 파고와 인공위성 관측 유의파고 차이의 특성 연구 (2004~2016))

  • WOO, HYE-JIN;PARK, KYUNG-AE;BYUN, DO-SEONG;LEE, JOOYOUNG;LEE, EUNIL
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.23 no.1
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    • pp.1-19
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    • 2018
  • In order to compare significant wave height (SWH) data from multi-satellites (GFO, Jason-1, Envisat, Jason-2, Cryosat-2, SARAL) and SWH measurements from Ieodo Ocean Research Station (IORS), we constructed a 12 year matchup database between satellite and IORS measurements from December 2004 to May 2016. The satellite SWH showed a root mean square error (RMSE) of about 0.34 m and a positive bias of 0.17 m with respect to the IORS wave height. The satellite data and IORS wave height data did not show any specific seasonal variations or interannual variability, which confirmed the consistency of satellite data. The effect of the wind field on the difference of the SWH data between satellite and IORS was investigated. As a result, a similar result was observed in which a positive biases of about 0.17 m occurred on all satellites. In order to understand the effects of topography and the influence of the construction structures of IORS on the SWH differences, we investigated the directional dependency of differences of wave height, however, no statistically significant characteristics of the differences were revealed. As a result of analyzing the characteristics of the error as a function of the distance between the satellite and the IORS, the biases are almost constant about 0.14 m regardless of the distance. By contrast, the amplitude of the SWH differences, the maximum value minus the minimum value at a given distance range, was found to increase linearly as the distance was increased. On the other hand, as a result of the accuracy evaluation of the satellite SWH from the Donghae marine meteorological buoy of Korea Meteorological Administration, the satellite SWH presented a relatively small RMSE of about 0.27 m and no specific characteristics of bias such as the validation results at IORS. In this paper, we propose a conversion formula to correct the significant wave data of IORS with the satellite SWH data. In addition, this study emphasizes that the reliability of data should be prioritized to be extensively utilized and presents specific methods and strategies in order to upgrade the IORS as an international world-wide marine observation site.

Analysis and Design of Profiling Adaptor for XML based Energy Storage System (XML 기반의 에너지 저장용 프로파일 어댑터 분석 및 설계)

  • Woo, Yongje;Park, Jaehong;Kang, Mingoo;Kwon, Kiwon
    • Journal of Internet Computing and Services
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    • v.16 no.5
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    • pp.29-38
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    • 2015
  • The Energy Storage System stores electricity for later use. This system can store electricity from legacy electric power systems or renewable energy systems into a battery device when demand is low. When there is high electricity demand, it uses the electricity previously stored and enables efficient energy usage and stable operation of the electric power system. It increases the energy usage efficiency, stabilizes the power supply system, and increases the utilization of renewable energy. The recent increase in the global interest for efficient energy consumption has increased the need for an energy storage system that can satisfy both the consumers' demand for stable power supply and the suppliers' demand for power demand normalization. In general, an energy storage system consists of a Power Conditioning System, a Battery Management System, a battery cell and peripheral devices. The specifications of the subsystems that form the energy storage system are manufacturer dependent. Since the core component interfaces are not standardized, there are difficulties in forming and operating the energy storage system. In this paper, the design of the profile structure for energy storage system and realization of private profiling system for energy storage system is presented. The profiling system accommodates diverse component settings that are manufacturer dependent and information needed for effective operation. The settings and operation information of various PCSs, BMSs, battery cells, and other peripheral device are analyzed to define profile specification and structure. A profile adapter software that can be applied to energy storage system is designed and implemented. The profiles for energy storage system generated by the profile authoring tool consist of a settings profile and operation profile. Setting profile consists of configuration information for energy device what composes energy saving system. To be more specific, setting profile has three parts of category as information for electric control module, sub system, and interface for communication between electric devices. Operation profile includes information in relation to the method in which controls Energy Storage system. The profiles are based on standard XML specification to accommodate future extensions. The profile system has been verified by applying it to an energy storage system and testing charge and discharge operations.

Relationship between Limnological Characteristics and Algal Bloom in Lake-type and River-Type Reservoirs, Korea (호소형 및 하천형 댐 호의 육수학적 특성과 조류발생과의 상관관계)

  • Kim, Jong-Min;Heo, Seong-Nam;Noh, Hye-Ran;Yang, Hee-Jeong;Han, Myung-Soo
    • Korean Journal of Ecology and Environment
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    • v.36 no.2 s.103
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    • pp.124-138
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    • 2003
  • This paper aimed to analyze the relationship between alga3 bloom patterns and hydrological, limnological data which were collected from major reservoirs in Korea for 8 years (1990${\sim}$1997). Water temperature of river-type reservoirs showed wider seasonal fluctuations than that of lake-type. pH of lake-type reservoirs was low in winter season but high in summer season. In contrast, river-type reservoirs showed high pH in spring and autumn seasons as well, and very low in summer season. COD of lake-type reservoirs and Paldang reservoir was lower (2${\sim}$3 mg/L) than that of Geumgang and Nagdonggang reservoirs (6${\sim}$9 mg/L). Dissolved oxygen (DO) of river-type reservoirs was higher than that of lake-type reservoirs. Seasonal fluctuation pattern of DO saturation in river-type reservoirs was high (80 ${\sim}$100%) and remained relatively constant whereas lake-type reservoirs showed the highest level (93%) in late spring or early summer, which gradually decreased entering winter season(46${\sim}$06%). And monthly variation of DO saturation showed inverse proportion to water volume in lake-type reservoirs. Nutrients concentration in river-type lake is higher than lake-type. Seasonal fluctuation of nutrients (T-N, T-P) in lake-type reservoirs was relatively small than that of river-type reservoirs. Annual mean N/P mass ratio of lake-type reservoirs was higher than that of river-type. Transparency tended to related with the suspended solid concentration in river-type reservoirs. Algal bloom of lake-type and river-type reservoirs occurred at any time except rainfall and winter periods. And it dominated in summer and early autumn, respectively. Algal bloom of river-type reservoirs was higher than that of lake-type. Relationship between rainfall and chlorophyll- a in lake-type reservoirs was relatively high, however river-type reservoirs showed insignificant.

Study on Effect of Convection Current Aeration System on Mixing Characteristics and Water Quality of Reservoir (대류식 순환장치의 저수지수체 유동특성 및 수질영향)

  • Lee, Yo-Sang;Lee, Kwang-Man;Koh, Deok-Koo;Yum, Kyung-Taek
    • Korean Journal of Ecology and Environment
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    • v.42 no.1
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    • pp.85-94
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    • 2009
  • This study examines the operational effectiveness of a Convection Current Aeration System (CCAS) in reservoir. CCAS was run from June, 2008 when the thermocline begun forming in the reservoir. This paper reviews the influence of stratification, dissolved oxygen dynamics and temperature in the lake's natural state from June to October 2008. The survey was done on a week basis. Upwelling flow effects a radius of $7{\sim}10m$ at a surface directly and was irrelevant to the strength of thermocline. On the other hand, it was affected the number of working days, and strength of thermocline at vertical profiles of the reservoir. Longer CCAS run, the deeper was the vertical direct flow area. However it didn't break the thermocline during summer season of 2008. The operating efficiency of the CCAS in the reservoir depends on hydraulics and meteological conditions. Computational Fluid Dynamics (CFD) is a very useful tool for evaluating the operating efficiency of fluid dynamics. The geometry for CFD simulation consists of a cylindrical vessel 25 m radius and 40 m height. The CCAS is located in center of domain. The non-uniform tetrahedral meshes had a bulk of the geometry. The meshes ranged from the coarse to the very fine. This is attributed to the cold water flowing into the downcomer and rising, creating a horizontal flow to the top of the CCAS. The result of CFD demonstrate a closer agreement with surveyed data for temperature and flow velocity. Theoretical dispersion volume were calculated at 8m depth, 120 m diameter working for 30 days and 10 m depth, 130 m diameter working for 50 days.

Possibility Estimating of Unaccessible Area on 1/5,000 Digital Topographic Mapping Using PLEIADES Images (PLEIADES 영상을 활용한 비접근지역의 1/5,000 수치지형도 제작 가능성 평가)

  • Shin, Jin Kyu;Lee, Young Jin;Choi, Hae Jin;Lee, Jun Hyuk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.32 no.4_1
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    • pp.299-309
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    • 2014
  • This paper evaluated the possibility for 1/5,000 digital topographic mapping by using PLEIADES images of 0.5m GSD(Ground Sampling Distance) resolution that has recently launched. Those results of check points by applying the initial RPC(Rational Polynomial Coefficient) of PLEIADES images came out as; RMSE of those were $X={\pm}1.806m$, $Y={\pm}2.132m$, $Z={\pm}1.973m$. Also, if we corrected geometric correction using 16 GCP(Ground Control Point)s, the results of RMSE became $X={\pm}0.104m$, $Y={\pm}0.171m$, $Z={\pm}0.036m$, and t he RMSE of check points were $X={\pm}0.357m$, $Y={\pm}0.239m$, $Z={\pm}0.188m$; which of those results indicated the accuracy of standard adjustment complied in error tolerances of the 1/5,000 scale. Additionally, we converted coordinates of points, obtained by TerraSAR. for comparing with measurements from GPS(Global Positioning System) surveying. The RMSE of comparing converted and GPS points were $X={\pm}0.818m$, $Y={\pm}0.200m$, $Z={\pm}0.265m$, which confirmed the possibility for 1/5,000 digital topographic mapping with PLEIADES images and GCPs. As method of obtaining GCPs in unaccessible area, however, the outcome evaluation of GCPs extracted from TerraSAR images was not acceptable for 1/5,000 digital topographic mapping. Therefore, we considered that further researches are needed on applicability of GCPs extracted from TerraSAR images for future alternative method.

Antimicrobial Activity of the Sargassum fulvellum Ethanol Extract and the Effect of Temperature and pH on Their Activity (모자반 에탄올 추출물의 항균활성과 열 및 pH 안정성)

  • Yoon, So-Young;Lee, So-Young;Kim, Koth-Bong-Woo-Ri;Song, Eu-Jin;Lee, So-Jeong;Lee, Chung-Jo;Park, Na-Bi;Jung, Ji-Yeon;Kwak, Ji-Hee;Nam, Ki-Wan;Ahn, Dong-Hyun
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.155-159
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    • 2010
  • The antimicrobial activity of Sargassum fulvellum (SF) was investigated using the agar diffusion assay and MIC test. In addition, the stability of this activity under extreme heat and pH conditions was examined. The SF ethanol extract was shown to display strong antimicrobial activities against B. subtilis, C. perfringens, L. plantarum, S. aureus, L. monocytogenes, S. cerevisae and C. tropicalis in the agar diffusion assay at the concentration of 4 mg/mL. The MIC value of the SF ethanol extract against the tested microbes ranged from 0.05 to 0.0063%. In the heat and pH stability test, the antimicrobial activity of the SF ethanol extract was not altered when the temperature was maintained at $121^{\circ}C$ for 15 min, and it was also not affected in the pH range of 2-10. These results suggest that the SF ethanol extract is highly stable against drastic changes in temperature and pH.

The Selection of the Most Painful Word in the Visual Analogue Scale(VAS) for Pain and the Psychosocial Factors in Association with Pain Assessment in Korean Adult Cancer Patients - for the Development of Korean Cancer Pain Assessment Tool(K-CPAT) by Delphi Method - ("표준형 성인 암성 통증 평가도구" 개발을 위한 시각통증등급의 최고통증강도 어휘 및 심리.사회적 평가 항목의 선정 - 델파이 방법을 이용 -)

  • Kim, Jin-Seo;Chun, Byung-Chul;Choi, Youn-Seon;Song, Chan-Hee;Yeom, Chang-Hwan;Lee, Myung-Aha;Lee, June-Young;Yoon, So-Young;Jang, Se-Kwon;Lee, Young-Hee;Lee, Kyoung-Uk;Lee, Chul;Park, Jean-No
    • Journal of Hospice and Palliative Care
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    • v.6 no.1
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    • pp.11-21
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    • 2003
  • This paper addresses the minor differences in the description of pain in Korean language in order to develop a standarized cancer pain aneument tool for Korean adults, Korean Cancer Pain Assessement Tool. The subtle differences in the meaning of expressions used cannot be translated into English and therefore we omiltted the English abstract.

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The Effect of LDL on Vibrio vulnificus Septicemia (비브리오 패혈증에 미치는 LDL의 영향)

  • Kim, Jong-Hyeon;Kim, Jong-Suk;Yoo, Wan-Hee;Hur, Hyeon
    • Journal of Food Hygiene and Safety
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    • v.21 no.4
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    • pp.213-217
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    • 2006
  • The halophilic bacterium Vibrio vulnificus is known to be a foodborne pathogen that causes septicemia in human. V. vulnificus infection is characterized by the high fatality rates and the primary attack against a person who have underlying diseases such as liver cirrhosis. However, there is no effective treatment for V. vulnificus septicemia except for classical treatments such as antibiotics. Recently, it has been known that lipoprotein (LDL) plays a major role in the protection against infection and inflammation. Consequently in this paper we analyzed the effects of LDL on V. vulnificus septicemia. We purified V. vulnificus cytolysin, a major virulent factor of V. vulnificus infection and measured inhibitory effects of mouse serum, cholesterol, and LDL on its hemolytic activity. Next experiments were performed to investigate whether LDL has a protective role against septicemia induced by V. vulnificus in mice. Intraperitoneal injection of LDL (1mg as protein) into mice 3hr before V. vulnificus $(1\times10^6\;CFU)$ injection, and V. vulnificus -induced lethality was determined. For the determination the relationship between LDL or cholesterol and prognosis, we determined serum levels of cholesterol and lipoprotein from V. vulnificus septicemia patients (n=15) who had visited the Chonbuk National University Hospital in Chonju. V. vulnificus cytolysin -induced hemolysis of mice erythrocytes was completely inhibited by serum, cholesterol, and low-density lipoprotein. V. vulnificus- induced lethality of mice injected with LDL showed only 40% compared to 100% of control. In survival groups (n=4) of V. vulnificus septicemia patients (n=15), their serum LDL and cholesterol revealed normal levels ($153.3{\pm}40.7,\;LDL;\;190.8{\pm}16.3$, Total cholesterol). However, in death groups (n=11) showed very low levels ($35.6{\pm}13.9,\;LDL;\;59.2{\pm}15.1$, Total cholesterol). Our study indicates that cholesterol and LDL are a prognosis indicator of V. vulnificus septicemia as well as an inhibitor of virulent action of V. vulnificus cytolysin. We suggested that the serum levels of cholesterol or LDL would be major index in the treatment and prevention of V. vulnificus septicemia.

Antimicrobial Activity of Paeonia japonica Extract and Its Quality Characteristic Effects in Sulgidduk (백작약 추출물의 항균효과 및 설기떡의 품질특성에 미치는 영향)

  • Choi, Hae-Yeon
    • Korean journal of food and cookery science
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    • v.25 no.4
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    • pp.435-444
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    • 2009
  • In this study, Paeonia japonica powder was extracted with ethanol, and its antimicrobial activity was investigated. The ethanol extract of the P. japonica had antimicrobial activity against Bacillus subtilis, Escherichia coli and Staphylococcus aureus. The inhibition zones of the P. japonica ethanol extract (3 mg/disc) against B. subtilis, E. coli and S. aureus were 10, 11, 8.5 mm, respectively. To test the food preservation effect of P. japonica and determine the optimal ratio of the P. japonica extract in the formulation, Sulgidduk samples were prepared with substitutions of 0, 0.25, 0.5, 0.75 and 1% P. japonica extract, and the quality characteristics of the samples were then investigated over 4 days of storage. In these experiments, total cell counts tended to decrease as the amount of added P. japonica extract increased. Moisture contents were not significantly different among the Sulgidduk samples. As the content of the P. japonica extract increased, the L-values of the samples decreased and the a- and b- values increased. In regards to the textural characteristics, the hardness, gumminess, and chewiness of the Sulgidduk samples decreased as the amount of P. japonica extract increased; however, they increased with the progression of storage time. Adhesiveness, springiness and cohesiveness were not significantly different at the different P. japonica extract concentrations and decreased with storage time. In the sensory evaluation, the control group had significantly higher scores for color, flavor and after taste as compared to the P. japonica extract added groups. When the P. japonica extract content was increased, the flavor and overall acceptability decreased, while Bakjakyak flavor, bitterness and off-flavor increased. Softness was not significantly different among the samples. In conclusion, the results indicate that substituting $0.25{\sim}1%$ P. japonica extract in Sulgidduk is optimal for quality and provides a product with reasonably high overall acceptability.