• Title/Summary/Keyword: Known sources

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Acoustic Noise Reduction of A SRM for Fan in Air conditioner (에어컨 팬 모터용 SRM의 소음 저감)

  • Lee, Dong-Il;Shin, Hyoun-Jeong;Lim, Jun-Young;Han, Seung-Do
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.816-821
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    • 2002
  • It is getting more important that energy efficiency and manufacturing cost of the electric motor in appliance. The SRM has been alternative choice. But acoustic noise and harshness in this motor was widely known. So this paper had been studied on the noise reduction of a SRM in air conditioner. This works include some parameters regarding to blown noise sources like a reluctance torque ripple, air gap eccentricity, Especially, it was focused on dynamic characteristics of the system based on mechanical viewpoint. It came to successful results. Besides, this gave us a validity of phase excitation in experimental measurements.

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The Estimation of Source Locations Based on Potential Gradients of In terpolation Polynomials of EEG Records (Interpolated EEG신호의 전위경사를 이용한 Source Location 추정)

  • 이용희;이응구
    • Journal of Biomedical Engineering Research
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    • v.15 no.1
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    • pp.105-110
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    • 1994
  • In this paper, we present a method to evaluate source locations and distributed region which is specified brain activity, as indicated by locations and strengths of intracranial sources, using potential gradients of interpolation polynomials and topographic mapping of the EEG records. This method can analyze the variance of source temporally or spatially and leads to enable a quantitative evaluation of potential gradients drawing methods which is now being used in the clinic. In the result, we obtained the overall potentials distribution on the entire scalp and the information of potential source locations from the EEG records of a patient which was known to epilepsy.

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Determinants of Health Information-Seeking Behavior: Implications for Post-Treatment Cancer Patients

  • Jung, Minsoo
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6499-6504
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    • 2014
  • Health information-seeking behavior (HISB) is active need-fulfillment behavior whereby health information is obtained from diverse sources, such as the media, and has emerged as an important issue within the transforming medical environment and the rise of medical consumers. However, little is known about the factors that affect HISB and its associations, and the health outcome of HISB. The aim of this study was to examine individual and social contextual factors associated with HISB and to systematically review their effects on health status among post-treatment cancer patients. Individual determinants of HISB included demographic factors, psychosocial factors, perceived efficacy and norms, and health beliefs. Contextual determinants of HISB encompassed community characteristics, neighborhood social capital, and media advocacy. Improving through factors on these two levels, HISB raised individuals' self-care management skills and medical treatment compliance, and enhanced shared decision-making and medical treatment satisfaction. Moreover, because HISB can differ according to individuals' social contextual conditions, it can give rise to communication inequalities. Because these can ultimately lead to health disparities between groups, social interest in HISB and balanced HISB promotion strategies are necessary.

Catechol 1,2-Dioxygenase from Rhodococcus rhodochrous N75 Capable of Metabolizing Alkyl-Substituted Catechols

  • Cha Chang-Jun
    • Journal of Microbiology and Biotechnology
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    • v.16 no.5
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    • pp.778-785
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    • 2006
  • Catechol 1,2-dioxygenase was purified from cells of R. rhodochrous N75 grown at the expense of benzoate and p-toluate as the sole sources of carbon. A single catechol 1,2-dioxygenase was found to be induced with either growth substrate. The enzyme has an estimated $M_r$ of 71,000 consisting of two identical subunits. Catechol 1,2-dioxygenase from R. rhodochrous N75 exhibits some unusual properties including: broad substrate specificity, extradiol cleavage activity with 4-methylcatechol and low $K_m$ values for halocatechols, suggesting that this enzyme is distinct from other known catechol and chlorocatechol 1,2-dioxygenases.

Dietary Supplements : Current Controversies in the United States

  • Kim, Jeong-Seon
    • Journal of Nutrition and Health
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    • v.30 no.6
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    • pp.727-732
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    • 1997
  • Dietary supplements are generally defined as concentrated sources of nutrients prescribed in addition to the daily diet to increase nutrient intake. These supplements are usually in the form of tablets, capsules, pills, powders, or liquids. Sales of dietary supplements are roughly $4 billion per year in the United States. Nearly 4 out of every 10 adults use dietary supplements regularly. This article is to report the pros and cons in the use of dietary supplements and a brief overview of current law, proposed regulations, and related activities in the United States. It provides what information should be known to the public before federal regulations governing health claims are made . These regulations may decide whether health food industries or pharmaceutical companies can make claims about the function of nutrients.

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Durability of the Solidified Mine Tailing-Hydrated Lime Mixture Against Repeated Freezing and Thawing (폐광미-소석회 고화체의 동결융해 내구성에 관한 연구)

  • Min, Kyoung-Won;Lee, Hyun-Cheol;Kim, Tae-Poong
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.65-69
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    • 2008
  • The tailings piled in abandoned mines are well-known potential sources of soil contamination. Hydrated limes were applied as cementing materials to solidify heavy metal contaminated tailings for the purpose of reducing their toxicity and migration rates. The optimum mixing ratio of tailings, hydrated lime, and water was determined through a preliminary test. The mixtures of mine tailings and hydrated lime solidified through pozzolanic reaction were tested for their durability against repeated freezing and thawing processes. After repeated freezing and thawing, the uniaxial compressive strengths of all the solidified mixture specimens decreased in comparison with those before test but still higher than $3.5kgf/cm^2$, the standard recommended for land reclamation solids by EPA(Environmental Protection Agency), which suggested that hydrated lime be a potential material to treat the abandoned mine tailings for the environmental purpose.

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Validation of Digital Holographic Particle Velocity Measurement System (디지털 홀로그래피 입자 속도 계측시스템의 검증)

  • Roh, H.S.;Kang, B.S.
    • Journal of ILASS-Korea
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    • v.18 no.3
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    • pp.119-125
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    • 2013
  • Digital holographic particle velocity measurement system can be a promising optical tool for the measurements of three dimensional particle velocities. In this research, validation experiments for the digital holographic particle velocity measurement system were conducted with measuring the velocities of glass beads on a rotating disk. Uncertainty analysis was performed to identify the sources of all relevant errors and to evaluate their magnitudes. The measurement results of particle velocities obtained with digital holographic method are compared reasonably well with the known values within acceptable range of errors. Moreover, digital holographic method showed better performance compared with that of optical holographic system.

Size measurements of galaxies in the nearby clusters (z<0.2) using the GALAPAGOS

  • Lee, Jae Hyung;Lee, Gwang-Ho;Lee, Myung Gyoon
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.66.2-66.2
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    • 2014
  • The size evolution of galaxies is one of the fascinating issues in these days. It is known that the size of a galaxy is closely related to other galactic properties, such as the central surface brightness, stellar mass, and redshift. However, we need to measure the sizes of galaxies precisely to understand those relations. We determine the sizes of early-type galaxies in the nearby clusters (z<0.2) using the GALAPAGOS. The GALAPAGOS is a tool which provides surface photometry for multiple sources, which make it fast and convenient to deal with huge image data. We run the GALAPAGOS individually to the Subaru/Suprime-Cam and the HST/ACS images for the same targets. We present and discuss the result of our size measurements for further applications.

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forecast and Warning Algorithm for U-city cyber terror protection (U-city 사이버 테러 방지를 위한 예.경보 알고리즘에 관한 연구)

  • Kim, Hyoung-Jung;Chung, Kyou-Il;Lee, Jun-Yeop
    • 한국정보통신설비학회:학술대회논문집
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    • 2009.08a
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    • pp.19-22
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    • 2009
  • This thesis offers forecast & warning algorithm about the accessing networks though statistical sampling methods to prevent computer terrors. These networks are occurred among U-city network groups. The main characteristic of current computer attacks is avoiding well-known detection patterns by successive changes in spreading speeds and attacking codes. The improvement of attacking stills leads to a problem causing the defense-time delay and creates vicious cycle that tries to fix networks after damage. Proposed algorithm notices and warns the potential attacking areas through defecting previous attacking signs, analysing attaching results ed tracing attaching sources at the beginning of the attack.

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A Study on the Compensation of Reactive Power by Power MOSFET INVERTER (전력용 MOSFET Inverter에 의한 무방전력보상에 관한 연구)

  • 이계호;김동필
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.36 no.3
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    • pp.163-170
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    • 1987
  • It is known that reactive component of AC power in the power system gives no energy to outside and cuses enlargiment of power apparatus, voltage fluctuation and unstability of power system. The power conversion system and control system which are composed of power semiconductor devices such as tyristor, transistor, GTO and so on have been appeared as new sources of reactive power. So the cmpensation of reactive power in power semiconductor systems is one of impending problem on the point of energy conservation and inprovement of power factor. This paper treates the fundamental review of the current type power compensation system that compensates the reactive power by MOSFET inverter. This inverter detects not only the reactive power of fundamental wave but also that of all harmoics created in the power semiconductor system and is scheduled to control by sampled value.

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