• 제목/요약/키워드: Mixed-source

검색결과 874건 처리시간 0.03초

Degradation of Chlorophenols and Phenol Mixtures by Cooperative Activities of Chlorophenol-degrading Strains

  • Bae, Hee-Sung;Cho, Young-Gyun;Lee, Sung-Taik
    • Journal of Microbiology and Biotechnology
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    • 제7권1호
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    • pp.43-48
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    • 1997
  • Three strains capable of degrading a chlorophenol were isolated by selective enrichment from soils contaminated with industrial wastewater. A Pseudomonas solanacearum TCP114 could use 2,4,6-trichlorophenol (TCP) as sole carbon and energy source, while two strains of Pseudomonas testosteroni CPW301 and Arthrobacter ureafaciens CPR706 could use 4-CP. All isolates also grew well on phenol. The degradation of one component by a pure strain was strongly affected by the presence of other compounds in the medium, CPW301 and CPR706 entirely lost the ability to degrade 4-CP and phenol in the presence of TCP. TCP114 also lost the ability to degrade phenol when 4-CP was added to the culture medium. These restrictions on the degradability could be overcome by employing defined mixed cultures (TCP114 and one strain of 4-CP degrading strains). All three components were successfully degraded by defined mixed cultures through their cooperative activities. It was also demonstrated that defined mixed cultures could be immobilized by using calcium alginate for the semi-continuous degradation of the three component mixture. Immobilization could not only accelerate the degradation rate, but also allowed the reuse of the cell mass several times without loss of the cells' degrading capabilities.

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수소-산소 혼합가스를 이용한 열절단 특성 (A Study on Thermal Cutting using Hydrogen-Oxygen Mixed Gas)

  • 김남인;장용원;이정수
    • 대한조선학회 특별논문집
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    • 대한조선학회 2008년도 특별논문집
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    • pp.126-132
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    • 2008
  • Cutting procedures whose qualifies are determined by various variables largely influences shipbuilding productivity. Particularly, defects in cutting shapes and cutting surface results in delay of the post shipbuilding stages such as welding and assemblage process. Because cutting procedures are influenced by various numbers of requirements according to the plate thickness, cutting precision can be maintained when the cutting conditions are appropriate. Existing cutting procedures utilize fossil fuels such as propane or ethylene as the main fuel component. Especially, when fossil fuel is applied to thick plate cutting, this process gives relatively slow cutting speed and generates large quantities of harmful polluting fumes. Recently, hydrogen-oxygen mixed gas generated by electrically dissociating water into Hydrogen and oxygen components is welcomed as an alternative fuel source. Also recent results report that alternative cutting fuel improves the cutting Dualities and speed. This paper presents that cutting characteristics and optimum cutting condition of hydrogen-oxygen mixed gas.

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혼합 상의 바나듐 산화물 박막 제작 및 에탄올 가스 감지 특성 연구 (Synthesis of Mixed Phase Vanadium Oxides Thin Films and Their Ethanol Gas Sensing Properties)

  • 한수덕;강종윤
    • 한국전기전자재료학회논문지
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    • 제31권1호
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    • pp.29-33
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    • 2018
  • Using a vanadium dioxide ($VO_2$) source, highly pure and amorphous vanadium oxide (VO) thin films were deposited using an e-beam evaporator at room temperature and high vacuum (<$10^{-7}$ Torr). Then, by controlling the post-annealing conditions such as $N_2:O_2$ pressure ratio and annealing time, we could easily synthesize a homogeneous $VO_2$ thin film and also mixed-phase VO thin films, including $VO_2$, $V_2O_5$, $V_3O_7$, $V_5O_9$, and $V_6O_{13}$. The crystallinity and phase of these were characterized by X-ray diffraction, and the surface morphology by FE-SEM. Moreover, the electrical properties and ethanol sensing measurements of the VO thin films were analyzed as a function of temperature. In general, mixed-phases as a self-doping effect have enhanced electrical properties, with a high carrier density and an enhanced response to ethanol. In summary, we developed an easy, scalable, and reproducible fabrication process for VO thin films that is a promising candidate for many potential electrical and optical applications.

중성자 에너지 측정을 위한 NE213-PSD 장치의 감응 분석 (Response Analysis of the NE213-PSD System for Neutron Energy Spectreum Measurement)

  • 이경주
    • 분석과학
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    • 제5권4호
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    • pp.367-372
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    • 1992
  • 방사선 중성자 선원의 에너지 스펙트럼을 측정하기 위하여 액체 섬광 검출기(NE213)와 펄스모형 분리장치를 감마선 선원과 중성자 선원을 이용하여 그 감응 특성을 분석하였다. Am-Be 선원을 이용하여 이 장치에 대한 "Figure of Merit"을 측정한 결과 1.13 이었다. 이 값은 단색 에너지 중성자 선원인 $^{12}C(d,\;n)^{13}N$에서의 1.3 과 상당히 유사한 값을 보여 준다. NE213-PSD 장치의 성능 시험을 위한 이 실험결과는 중성자-감마 혼합 방사선장에서 스펙트럼의 측정과 중성자 에너지 스펙트럼과 속밀도 측정표준을 확립하는 데 기술적으로 유용하게 쓰일 것이다.

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ICA 기법을 이용한 구조물의 진동원 신호 규명 (Vibration Source Signal Identification of Structures Using ICA)

  • 김국현;권혁민;조대승;김재호;전재진
    • 대한조선학회논문집
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    • 제49권6호
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    • pp.498-503
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    • 2012
  • Independent component analysis (ICA) technique based on statistical independency of the signals is known as suitable to identify the source signals by measuring and separating mixed signals through transfer paths and has successfully applied in the field of medical care, communications and so forth. In this study, the ICA technique is introduced for the identification of excitation sources from measured vibration signals of structures, which can be done by evaluating negentropy of centered and whitened vibration signals and correlation of separated signals. To validate the method, numerical analyses are carried out for a plate and a cylinder structure. The results show that the method can be applied efficiently to source identification of complex structures. Nevertheless, additional studies would be required to complement problems of occasional inaccuracy.

Modeling of Heart Phantom using the Multidipole Current Source

  • Jang, Kwan-Hee;Yoon, Dal-Hwan;Min, Seung-Gi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1957-1962
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    • 2003
  • In order to design the phantom of heart, we have developed the multi-dipole current source system. Such a one be clue to the various motion of heart. The magnetocardiograph (MCG) system for diagnosing the disease of the heart due to an analysis of the heart signal. The multidipole current source system be built by microprocessor. We use the shield room to obtain a good experimental result. Then the signal acquired is mixed with a background noise, through a filtering extracts a pure signal. The pure signal such a heart phantom is analyzed by an electromagnetic map.

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LPG 엔진의 냉 시동시 시동성 개선 및 배출들 저감을 위한 연구 (A Study for the Improvement of Start Ability and Exhaust Emissions in a Conventional Mixer Type LPG Engine on Cold Start)

  • 김우석;이종화
    • 한국자동차공학회논문집
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    • 제10권1호
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    • pp.84-92
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    • 2002
  • On the cold start of LPG engine, as the engine temperature has not reached its equilibrium temperature, liquid LPG could not be changed perfectly gaseous LPG, although it was passed to the vaporizer. Liquid and gas mixed fuel could influence starting ability and exhaust emission characteristics of LPG engine. In this study, the vaporization characteristic of liquid LPG was investigated with a conventional vaporizer and the vaporizer with heat source(glow plug) installed at preheated chamber inlet, by using the visualization methods and engine test. According to visualization result, even if the engine coolant temperature was $14^{\circ}C$, liquid fuel was supplied to primary chamber over 25 seconds without vaporizing from preheated chamber in such a conventional vaporizer. However, the vaporizer with heat source do not correspond with that, scarcely had been trim on glow plug when LPG began to vaporize. The effectiveness of heat source could be verified by application to the conventional LPG engine.

Blind Source Separation U sing Variable Step-Size Adaptive Algorithm in Frequency Domain

  • Park Keun-Soo;Lee Kwang-Jae;Park Jang-Sik;Son Kyung Sik
    • 한국멀티미디어학회논문지
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    • 제8권6호
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    • pp.753-760
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    • 2005
  • This paper introduces a variable step-size adaptive algorithm for blind source separation. From the frequency characteristics of mixed input signals, we need to adjust the convergence speed regularly in each frequency bin. This algorithm varies a step-size according to the magnitude of input at each frequency bin. This guarantee of the regular convergence in each frequency bin would become more efficient in separation performances than conventional fixed step-size FDICA. Computer simulation results show the improvement of about 5 dB in signal to interference ratio (SIR) and the better separation quality.

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예측지원시스템에 의한 직관적 예측의 행태에 관한 연구 (Interactive Judgemental Adjustment of Initial Forecasts with forecasting Support Systems)

  • Lim, Joa-Sang;Park, Hung-Kook
    • 한국경영과학회지
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    • 제24권1호
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    • pp.79-98
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    • 1999
  • There have been a number of empirical studios on the effectiveness of Judgmental adjustment to statistical forecasts Generally the results have been mixed. This study examined the impact of the reliability and the source of the additionally presented reference forecast upon the revision process in a longitudinal time series forecasting task with forecast support systems. A 2-between(reliability & source). 2-within(seasonality & block) factorial experiment was conducted with post-graduate students using real time series. Judgmental adjustment was found to improve the accuracy of initial eyeballing irrespective of the reliability of an additionally presented forecast. But it did not outperform the dampened reference forecast. No effect was found of the way the source of the reference forecast was framed. Overall the subjects anchored heavily on their Initial forecast and relied too little on the reference forecast irrespective of its reliability. Moreover they did not improve at the task over time, despite immediate outcome feedback.

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순시전원제어에 의한 수산화가스 발생장치에 관한 연구 (A Study on Brown Gas Generator with Instantaneous Source Power Control)

  • 전윤석;이상용;목형수;최규하
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2003년도 하계학술대회 논문집 B
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    • pp.1093-1095
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    • 2003
  • The mixed gas of Hydrogen and Oxygen has obtained from water electrolysis reaction. It has constant volume ratio 2 : 1 Hydrogen and Oxygen, and it is used as a source of thermal energy by combustion reaction. In this paper, Brown Gas Generator with Instantaneous source power control method is designed and relationship between brown gas quantities, efficiency and power condition is studied.

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