• Title/Summary/Keyword: Sources of variation

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Production of Antifungal Lipopeptide Iturin by Bacillus subtilis (Bacillus subtilis로부터 항진균 리포펩타이드 물질 Iturin의 생산)

  • 손광현;이항우
    • KSBB Journal
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    • v.9 no.2
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    • pp.224-229
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    • 1994
  • Iturin, an antifungal lipopeptide, fermentation by Bacillus subtilis was investigated focusing on the effeats of nutrients aeration and specific cell growth rate on iturin production. Cell growth and product formation were not affected by different kinds of carbon sources such as sucrose, glucose and fructose. Soytone concentration above 20g/$\ell$ did not influence iturin production. Diauxic growth pattern appeared when only soytone was used as a sole nitrogen source probably due to the shortage of amino acids and/or peptides in soytone which could be favorably assimilated by the cells. The composition of three major components in iturin was not changed significantly by the variation of dissolved oxygen concentration of the culture broth but changed substantially by the change of specific growth rate of the cells.

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Krein Space Robust Extended Kalman filter Design for Pose Estimation of Mobile Robots with Wheelbase Uncertainties (휠베이스에 불확실성을 갖는 이동로봇의 자세 추정을 위한 크라인 스페이스 강인 확장 칼만 필터의 설계)

  • Jin, Seung-Hee;Yoon, Tae-Sung;Park, Jin-Bae
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.433-436
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    • 2003
  • The estimation of the position and the orientation for the mobile robot constitutes an important problem in mobile robot navigation. Although the odometry can be used to describe the motions of the mobile robots, there inherently exist the gaps between the real robots and the mathematical model, which may be caused by a number of error sources contaminating the encoder outputs. Hence, applying the standard extended Kalman filter for the nominal model is not supposed to give the satisfactory performance. As a solution to this problem, a new robust extended Kalman filter is proposed based on the Krein space approach. We consider the uncertain discrete time nonlinear model of the mobile robot that contains the uncertainties represented as sum quadratic constraints. The proposed robust filter has the merit of being constructed by the same recursive structure as the standard extended Kalman filter and can, therefore, be easily designed to effectively account for the uncertainties. The simulations will be given to verify the robustness against the parameter variation as veil as the reliable performance of the proposed robust filter.

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Research on Technopark Management Performance Comparison Based on National Quality Awards Appraisal Standard by Countries (국가별 국가품질상 평가기준에 따른 테크노파크 경영실적 비교 연구)

  • Hwang, Sung-Taek;Park, Jong-Woo
    • Journal of Korean Society for Quality Management
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    • v.40 no.4
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    • pp.497-512
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    • 2012
  • Purpose: Most major countries have their own set of qualifications called national quality awards to measure the quality of companies and organizations. This study analyzes 3 different national quality awards and compare with the result from Korean quality awards conducted by Ministry of knowledge and Economy and Korea institute for advancement of technology. Methods: We tested 17 technoparks out of 18 technoparks in Korea and see how different the results can be depends on the value weights. We closely looked at each qualifications and tables of different countries' awards and compared with one used in Korea. Finally we proposed some suggestions to use not only domestic model but also international ones to be objective and add efficiency to organizations. Results: Depend on similarity of qualifications and weights, there were countries with different results and these caused score and ranking changes. Nevertheless, there was a comparison that did not make any changes on both score and ranking. Conclusion: We recognized the limitation that a standardized quality variation cannot be enough sources to test and analyze technoparks with different size and criteria. Integrating global standards and flow would be the first step to help grow technoparks and organizations placed in Korea in days to come.

Characteristics of Aerosol Size Distribution from OPC Measurement in Seoul, 2001 (OPC(광학적 입자 계수기)로 측정한 2001년 서울지역 에어로졸의 입경 분포)

  • 정창훈;전영신;최병철
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.5
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    • pp.515-528
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    • 2003
  • The characteristics of one year observation aerosol data in Seoul, 200 I was studied using an OPC (Optical Particle Counter). The size resolved aerosol number concentrations of 0.3 ∼ 25 11m were measured. The results were compared with PM$_{10}$ mass concentration data under various meteorological conditions including dust and precipitation events. For fine particles whose diameter is less than 2.23 ${\mu}{\textrm}{m}$, the number concentration increases in the early morning which is considered due to transportation. while the coarse mode particles increase during daytime. This increase can be explained as local sources and human activities near sampling site. Hourly averaged data show that there exists diurnal variation. Generally, PM$_{10}$ data showed a similar tendency with OPC data. The size resolved OPC data showed that the particles of 0.5 ∼ 3.67 ${\mu}{\textrm}{m}$ are positively correlated with PM$_{10}$ data. The accumulated volume fraction of size resolved aerosol concentration in 0.5 ∼ 10 ${\mu}{\textrm}{m}$ showed that 0.5 ∼ 2.23 ${\mu}{\textrm}{m}$ particles occupied 59.2% of total aerosol volume of 0.5 ∼ 10 ${\mu}{\textrm}{m}$./TEX>.

Type II analysis by projections (사영을 이용한 제2종 분석)

  • Choi, Jaesung
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.6
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    • pp.1155-1163
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    • 2012
  • This paper suggests a method for getting sums of squares due to sources of variation under the assumption of two-way fixed effects model. The method used for calculating the quantities due to fixed-effects is based on the projections of an observation vector y on the column space generated by the model matrix X under the assumed model. The suggested method shows that the calculation of Type II sums of squares by projections is much easier than the classical Type II analysis.

Method of Particle Contamination Control for Yield Enhancement in the Cleanroom (클린룸 제조공정에서 수율개선을 위한 입자오염제어 방법)

  • Noh, Kwang-Chul;Lee, Hyeon-Cheol;Kim, Dae-Young;Oh, Myung-Do
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.31 no.6 s.261
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    • pp.522-530
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    • 2007
  • The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was proposed, which are composed of data collection, data analysis, improvement action, verification, and implement control. The partition check method and the composition analysis for data collection and data analysis were respectively used in the main board and the cellular phone module production lines. And these methods were evaluated by the variation of yield loss between before and after improvement action. In case that the partition check method was applied, the critical process step was selected and yield loss reduction through improvement actions was observed. While in case that the composition analysis was applied, the critical sources were selected and yield loss reduction through improvement actions was also investigated. From these results, it is concluded that the partition check and the composition analysis are effective solutions for particle contamination control in the cleanroom production lines.

Calcium in infectious hematopoietic necrosis virus (IHNV) infected fish cell lines

  • Kim, Nam-Shik;Heo, Gnag-Joon;Lee, Chang-Hee
    • Journal of Microbiology
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    • v.34 no.3
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    • pp.253-269
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    • 1996
  • Infection of fish cells with IHNV resulted in gradual increase in cytosolic free Ca$\^$2+/ concentration ([Ca$\^$2+/)] in CHSE, gradual decrease in [Ca$\^$2+/] in FHM, and no significant change in RTG cells. The degree of [Ca$\^$2+/] increase or decrease was dependent on the amount of infectious virus, and these [Ca$\^$2+/] variations were maximal at 16 hours after virus infection (p. i.) in both cell lines. When the fish cells were infected with inactivated IHNV, evident variation in [Ca$\^$2+/] was not observed. Thus, infectivity of IHNV appears to correlate with changes in [Ca$\^$2+/] in virus-infected cells. These IHNV-induced [Ca$\^$2+/] changes were partially blocked by cycloheximide, but not affected by cordycepin. It seems to be that virus-induced Ca$\^$2+/ variations were more related with protein synthesis than RNA synthesis. Various Ca$\^$2+/ related drugs were used in search for the mechanisms of the [Ca$\^$2+/], changes following IHNV infection of CHSE cells. Decreasing extracellular Ca$\^$2+/ concentration or blocking Ca$\^$2+/ influx from extracellular media inhibited the IHNV-induced increase in [Ca$\^$2+/], in CHSE cells. Similar results were obtained with intracellular Ca$\^$2+/ sources are important in IHNV-induced [Ca$\^$2+/] increase in CHSE cells.

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An Adaptive Transform Code for Images (적응 변환코드를 이용한 영상신호 압축)

  • Kim, Dong-Youn;Lee, Kyung-Joung;Yoon, Hyung-Ro
    • Proceedings of the KOSOMBE Conference
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    • v.1991 no.11
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    • pp.44-47
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    • 1991
  • There exists a transform trellis code that is optimal for stationary Gaussian sources and the squared-error distortion measure at all rates. In this paper, we train an asymptotically optimal version of such a code to obtain one which is matched better to the statistics of real world data. The training algorithm uses the M-algorithm to search the trellis codebook and the LBG-algorithm to update the trellis codebook. To adapt the codebook for the varying input data. we use two gain-adaptive methods. The gain-adaptive scheme 1, which normalizes input block data by its gain factor, is applied to images at rate 0.5 bits/pixel. When each block is encoded at the same rate, the nonstationarity among the block variances leads to a variation in the resulting distortion from one block to another. To alleviate the non-uniformity among the encoded image, we design four clusters from the block power, in which each cluster has its own trellis codebook and different rates. The rate of each cluster is assigned through requiring a constant distortion per-letter. This gain-adaptive scheme 2 produces good visual and measurable quality at low rates.

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Absolute sound level algorithm for contents platform (콘텐츠 플랫폼 적용을 위한 절대음량 알고리즘)

  • Gyeon, Du-Heon
    • The Journal of the Acoustical Society of Korea
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    • v.39 no.5
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    • pp.424-434
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    • 2020
  • This paper describes an algorithm that calculates Absolute Sound Level (ASL) for contents platform. ASL is a single volume representing individual sound sources and is a concept designed to integrate and utilize the sound level units in digital sound source and physical domain from a speaker in practical areas. For this concept to be used in content platforms and others, it is necessary to automatically derive the ASL without having to go through a hearing of mastering engineers. The key parameters of which a person recognizes the representative sound level of an individual single sound source are the areas of "frequency, maximum energy, energy variation coefficient, and perceived energy distribution," and the ASL was calculated through the normalizing of the weights.

Spatio-temporal dependent errors of radar rainfall estimate for rainfall-runoff simulation

  • Ko, Dasang;Park, Taewoong;Lee, Taesam;Lee, Dongryul
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.164-164
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    • 2016
  • Radar rainfall estimates have been widely used in calculating rainfall amount approximately and predicting flood risks. The radar rainfall estimates have a number of error sources such as beam blockage and ground clutter hinder their applications to hydrological flood forecasting. Moreover, it has been reported in paper that those errors are inter-correlated spatially and temporally. Therefore, in the current study, we tested influence about spatio-temporal errors in radar rainfall estimates. Spatio-temporal errors were simulated through a stochastic simulation model, called Multivariate Autoregressive (MAR). For runoff simulation, the Nam River basin in South Korea was used with the distributed rainfall-runoff model, Vflo. The results indicated that spatio-temporal dependent errors caused much higher variations in peak discharge than spatial dependent errors. To further investigate the effect of the magnitude of time correlation among radar errors, different magnitudes of temporal correlations were employed during the rainfall-runoff simulation. The results indicated that strong correlation caused a higher variation in peak discharge. This concluded that the effects on reducing temporal and spatial correlation must be taken in addition to correcting the biases in radar rainfall estimates. Acknowledgements This research was supported by a grant from a Strategic Research Project (Development of Flood Warning and Snowfall Estimation Platform Using Hydrological Radars), which was funded by the Korea Institute of Construction Technology.

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