• Title/Summary/Keyword: Rep. of Korea

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A Study on Automatic Calculation of Earth-volume Using 3D Model of B-Rep Solid Structure (B-Rep Solid 구조의 3차원 모델을 이용한 토공량 자동 산정에 관한 연구)

  • Kim, Jong Nam;Um, Dae Yong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.40 no.5
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    • pp.403-412
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    • 2022
  • As the 4th industrial revolution is in full swing and next-generation ICT(Information & Communications Technology) convergence technology is being developed, various smart construction technologies are being rapidly introduced in the construction field to respond to technological changes. In particular, since the earth-volume calculation process for site design accounts for a large part of the design cost at the construction site, related researches are being actively conducted to improve the efficiency of the process and accurately calculate the earth-volume. The purpose of this study is to present a method for quickly constructing the topography of a construction site in 3D and efficiently calculating earth-volume using the results. For this purpose, the construction site was constructed as a 3D realistic model using large-scale aerial photos obtained from UAV(Unmanned Aerial Vehicle). At this time, since the constructed 3D realistic model has a surface model structure in which volume calculation is impossible, the structure was converted into a 3D solid model to enable volume calculation. And we devised a methodology to calculate earth-volume based on CAD(Computer-Aided Design and Drafting) using the converted solid model. Automatically calculating earth-volume from the solid model by applying the method. As a result, It was possible to confirm a relative deviation of 1.52% from the calculated earth-volume from the existing survey results. In addition, as a result of comparative analysis of the process time required for each method, it was confirmed that the time required is reduced of 60%. The technique presented in this study is expected to be utilized as a technology for smart construction management, such as periodic site monitoring throughout the entire construction process, as well as cost reduction for earth-volume calculation.

Survey in consumers and distribution stages bacteriological analysis for fresh raw beef in Gwangju area, Korea (광주지역 소 생고기 선호도 및 유통단계별 세균학적 분석)

  • Na, Ho-Myung;Bae, Seong-Yeol;Koh, Ba-Ra-Da;Jang, Mi-Sun;Sung, Chang-Min;Kim, Ji-Yeon;Park, Heon-Gyu;Mun, Yong-Un;Kim, Yong-Hwan
    • Korean Journal of Veterinary Service
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    • v.35 no.4
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    • pp.313-319
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    • 2012
  • Consumer's preference and microbial inspections on fresh raw beef were carried out to understand the actual market status in Gwanju, Korea. Over 15 questions on questionnaire by 1,111 randomly selected respondents between April and May in 2011, results showed 65.5% positive on eating fresh raw beef, 63.8% negative on good hygiene condition of fresh raw beef, and 72.5% positive on the secure of the hygiene-safety for priority program, respectively. For microbial inspections, a total of 302 samples were collected from fresh raw beef purchased from slaughterhouse (n=122), transport (n=69) and consumer (n=81) stage, from lettuce (n=30) at consumer stage. The aerobic plate count (APC), E. coli count and food borne bacteria such as Salmonella spp., Listeria monocytogenes, Staphylococcus(S.) aureus and E. coli O157:H7 were tested in the samples. As results, the level of count on APC of fresh raw beef ranged $6{\times}10^1{\sim}1.8{\times}10^5CFU/g$ from slaughterhouse, $2{\times}10^2{\sim}8.3{\times}10^5CFU/g$ from transport stage and $1{\times}10^2{\sim}4{\times}10^5CFU/g$ from consumer stage. The level of count on E. coli of fresh raw beef ranged $1{\sim}9{\times}10^1CFU/g$ from slaughterhouse, $1{\sim}7{\times}10CFU/g$ from transport stage and $1{\sim}5.5{\times}10CFU/g$ from consumer stage. In total, 26 S. aureus were isolated, 10 (14.5%) from fresh raw beef at transport stage, 12 (14.8%) from fresh raw beef and 4 (13.3%) from lettuce at consumer stage. Enterotoxin of S. aureus was not detected among 26 isolates. All S. aureus isolates were typed using a DiversiLab$^{TM}$ rep-PCR system for genetic similarity test, showing over 95% of genetic relationship amon isolates.

A New Direct Torque Control Method of Induction Motor for Torque Ripple Reduction

  • Kim, Deok-Ki;Kim, Jong-Su;Kim, Sung-Hwan;Kim, Hyun-Soo;Kim, Won-Ouk;Yoon, Kyoung-Kuk;Oh, Sae-Gin
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.7
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    • pp.1061-1067
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    • 2008
  • Direct Torque Control[DTC] and Vector Control are the two schemes developed for high performance induction motor drives. DTC based induction motors are being increasingly used in various industrial applications. DTC offers fast torque response and better speed control with lesser hardware and processing costs as compared to vector controlled drives. However, conventional DTC suffers from high torque ripple, current harmonics and low performance during torque transients. In this paper a new Direct Torque Control[DTC] method of induction motor is presented. In comparison with the conventional DTC method, the PWM technique is applied to proposed control method. In this method, decoupling mechanism is not required and the torque, the flux magnitude are under control using PI controllers and generating the voltage command for inverter control. Therefore torque and speed ripple could be reduced in comparison with the conventional switching table DTC.

Hydraulic Characteristics of Anaerobic Fluidized Bed Bioreactor (혐기성 유동상 반응기의 수리학적 특성)

  • Seok, Jong-Hyuk
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.90-96
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    • 2018
  • Tracer experiments were carried out on two laboratory modes, "without media mode" and "with media mode", to examine the hydraulic characteristics of the anaerobic fluidized bed bioreactor (AFBR). For both configurations, a formula was derived for the hydraulics and data interpretation to obtain the actual characteristics of the reactor. The dispersion model is based on the assumption that carriers are non-reacting and the dispersion coefficient is constant. The model represents the one-dimensional unsteady-state concentration distribution of the non-reacting tracer in the reactors. The experimental results showed that the media increased the mixing conditions in the reactor considerably. For the reactor without media, in the range tested, the dispersion coefficient was at least an order of magnitude smaller than that of the reactor with media. Advective transport dominates and the flow pattern approaches the plug flow reactor (PFR) regime. The dispersion coefficient increased significantly as us, the superficial liquid velocity, was increased proportionally to 0.82cm/s. On the other hand, for the reactor with media, the flow pattern was in between a PFR and a completely mixed flow reactor (CMFR) regime, and the dispersion coefficient was saturated at us=0.41cm/s, remaining relatively constant, even at us=0.82cm/s. The dispersion coefficient depends strongly on the liquid Reynolds number (Re) or the particle Reynolds number (Rep) over the range tested.

Comparison on the Korea New Technology Certification System (한국의 신기술 인증제도 비교)

  • 송학현;최세하;김하식;김윤호
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.7
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    • pp.1363-1368
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    • 2003
  • The subject of the national new Technology certification system is in which domestic enterprise have competition above international market. Rep. of the korea Government Ministry of Information and communication(MIC), Ministry of science and technology(MOST), Ministry of Commerce, Industry and energy(MOCIE), Ministry of Construction and Transportation(MOCT), Ministry of Marin and fishery(MOAf) executive the certification Regulations. These Ministry have the new Technology certification rules each of the scope of the their nam job. These rules same the subject, proposal qualification and the property, but difference certification reference. So, this article suggestions about new Technology certification system.

The Analytical Radioactive Waste Repository Source Term REPS Model (방사성폐기물 처분장 선원항 REPS 모델)

  • Kim, Chang-Lak;Cho, Chan-Hee;Park, Kwang-Sub;Kim, Jinwung
    • Nuclear Engineering and Technology
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    • v.22 no.4
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    • pp.315-325
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    • 1990
  • The analytical repository source term (REPS) computer code is developed for the safety assessment of radioactive waste geologic repository. For reliable prediction of the leach rates for various radionuclides, degradation of concrete structures, corrosion rate of waste container, degree of corrosion on the container surface, and the characteristics of radionuclides are considered in this REPS code. For the validation of the radionuclide leach rates predicted by the REPS model, the calculated leach rates of Cs-137, Sr-85, and Co-60 are compared with two reported leaching test results. Cesium and strontium leach congruently, and the leaching test results of these species can be reproduced by the congruent leaching model included in the REPS model. In case of cobalt, the solid diffusion model is in good agreement with the leaching test results.

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Countermeasures against Security Threats to Online Voting Using Distributed Ledger Technology (분산 원장 기술을 활용한 온라인 투표에 대한 보안 위협과 대응 방안)

  • Park, Keundug;Kim, ChangOh;Youm, Heung-youl
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.5
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    • pp.1201-1216
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    • 2017
  • Recently, many countries around the world including Korea (Rep. of) have actively introduced online voting using distributed ledger technology (e.g. blockchain). However, online voting using distributed ledger technology based on the widely deployed telecommunication/ICT infrastructure. There is insufficient analysis of potential security threats. In this paper, we suggest a model for online voting system using distributed ledger technology and propose countermeasures by analyzing the security threats that may occur in online voting process in terms of information security.

Recommendation of Nitrogen Topdressing Rates at Panicle Initiation Stage of Rice Using Canopy Reflectance

  • Nguyen, Hung T.;Lee, Kyu-Jong;Lee, Byun-Woo
    • Journal of Crop Science and Biotechnology
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    • v.11 no.2
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    • pp.141-150
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    • 2008
  • The response of grain yield(GY) and milled-rice protein content(PC) to crop growth status and nitrogen(N) rates at panicle initiation stage(PIS) is critical information for prescribing topdress N rate at PIS(Npi) for target GY and PC. Three split-split-plot experiments including various N treatments and rice cultivars were conducted in Experimental Farm, Seoul National University, Korea in 2003-2005. Shoot N density(SND, g N in shoot $m^{-2}$) and canopy reflectance were measured before N application at PIS, and GY, PC, and SND were measured at harvest. Data from the first two years(2003-2004) were used for calibrating the predictive models for GY, PC, and SND accumulated from PIS to harvest using SND at PIS and Npi by multiple stepwise regression. After that the calibrated models were used for calculating N requirement at PIS for each of nine plots based on the target PC of 6.8% and the values of SND at PIS that was estimated by canopy reflectance method in the 2005 experiment. The result showed that SND at PIS in combination with Npi were successful to predict GY, PC, and SND from PIS to harvest in the calibration dataset with the coefficients of determination ($R^2$) of 0.87, 0.73, and 0.82 and the relative errors in prediction(REP, %) of 5.5, 4.3, and 21.1%, respectively. In general, the calibrated model equations showed a little lower performance in calculating GY, PC, and SND in the validation dataset(data from 2005) but REP ranging from 3.3% for PC and 13.9% for SND accumulated from PIS to harvest was acceptable. Nitrogen rate prescription treatment(PRT) for the target PC of 6.8% reduced the coefficient of variation in PC from 4.6% in the fixed rate treatment(FRT, 3.6g N $m^{-2}$) to 2.4% in PRT and the average PC of PRT was 6.78%, being very close to the target PC of 6.8%. In addition, PRT increased GY by 42.1 $gm^{-2}$ while Npi increased by 0.63 $gm^{-2}$ compared to the FRT, resulting in high agronomic N-use efficiency of 68.8 kg grain from additional kg N. The high agronomic N-use efficiency might have resulted from the higher response of grain yield to the applied N in the prescribed N rate treatment because N rate was prescribed based on the crop growth and N status of each plot.

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Iron Containing Superoxide Dismutase of Streptomyces subrutilus P5 Increases Bacterial Heavy Metal Resistance by Sequestration (Streptomyces subrutilus P5의 철 함유 Superoxide Dismutase의 중금속 격리에 의한 세균의 중금속 저항성 증가)

  • Kim, Jae-Heon;Han, Kwang Yong;Jung, Ho Jin;Lee, Jungnam
    • Korean Journal of Microbiology
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    • v.50 no.3
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    • pp.179-184
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    • 2014
  • Mitigation of heavy metal toxicity by iron containing superoxide dismutase (FeSOD) of Streptomyces subrutilus P5 was investigated. For E. coli $DH5{\alpha}$, the survival rate in the presence of 0.1 mM lead ions was only 7% after 120 min; however, with the addition of $0.1{\mu}M$ of purified native FeSOD the survival rate increased to 39%. This detoxification effect was also shown with 0.01 mM copper ions (survival increased from 6% to 50%), and the effect was stronger than with the use of EDTA. E. coli M15[pREP4] producing 6xHis-tagged FeSOD was constructed, and this showed an increase in survival rates throughout the incubation time; in the presence of 0.1 mM lead ions,the final increase at 60 min was from 3% to 19%. The FeSOD absorbed about 123 g-atom lead per subunit; therefore, we suggest that FeSOD could sequestrate toxic heavy metals to enhance bacterial survival against heavy metal contamination.

Molecular Characterization and Antimicrobial Susceptibility of Biofilm-forming Acinetobacter baumannii Clinical Isolates from Daejeon, Korea (대전지역에서 분리된 생물막 형성 Acinetobacter baumannii 임상분리주의 분자유전학적 특성과 항균제 감수성양상)

  • Sung, Ji Youn
    • Korean Journal of Clinical Laboratory Science
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    • v.50 no.2
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    • pp.100-109
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    • 2018
  • The emergence and dissemination of multidrug-resistant (MDR) Acinetobacter baumannii isolates have been reported worldwide, with most of these possessing the ability to form biofilms. Biofilm formation is an important virulence factor associated with the resistance to disinfection and desiccation. This study examined the genetic basis of antimicrobial resistance mechanisms of biofilm-forming A. baumannii clinical isolates. Imaging and quantification of biofilms were performed by a crystal violet assay and 46 biofilm-forming A. baumannii isolates were selected. Subsequently, 16 isolates belonging to different clones were identified using REP-PCR, and detection of the antimicrobial determinants in the isolates was carried out. The 16 isolates included 9 non-MDR and 7 MDR isolates. The mean biomass $OD_{560}$ values of the non-MDR (0.96) and MDR (1.05) isolates differed but this difference was not significant. In this study, most biofilm-forming MDR A. baumannii isolates contained various antimicrobial resistance determinants ($bla_{OXA-23}$, armA, and mutations of gyrA and parC). On the other hand, most biofilm-forming non-MDR A. baumannii isolates did not contain antimicrobial resistance determinants. These results suggest that there is little correlation between the biofilm-forming ability and antimicrobial susceptibility in A. baumannii isolates. In addition, the emergence of MDR A. baumannii clinical isolates is generally caused by mutations of the genes associated with antimicrobial resistance and/or the acquisition of various antimicrobial resistance determinants.