• Title/Summary/Keyword: induction period

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Effect of Amino acids on the Oxidation of Linoleic acid (일부 아미노산이 Linoleic acid의 산화반응에 미치는 영향)

  • Lee, Joon Ho;Lee, Eun Hee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.12 no.4
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    • pp.336-341
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    • 1983
  • A study on the oxidation effect of some amino acids(glutamic acid, phenylalanine, alanine) addition to the linoleic acid emulsion was conducted. Amino acid solutions in concentrations of $10^{-2}$, $10^{-3}$ and $10^{-4}M$ were mixed with equal volume of linoleic acid emulsions. The prepared samples were incubated at $60{\pm}1^{\circ}C$ and the extent of diene conjugation and TBA values were measured by using the UV visible spectrophotometer. The results were as follows: 1) From the extent of diene conjugation, we found that the addition of phenylalanine and alanine prolonged the induction period and the addition of glutamic acid shortened. There was an optimum concentration for each amino acid to act as an antioxidant during the induction period. The optimum concentration of alanine was $10^{-3}M$ and that of phenylalanine was $10^{-2}M$. 2) The results of TBA values showed that three amino acids possesed antioxidant activity after the induction period. There was also an optimum concentration to act as antioxidant after the induction period. The optimum concentrations of glutamic acid, phenylalanine, and alanine were $10^{-2}$, $10^{-3}$, and $10^{-3}M$, respectively.

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Photoperiodic Floral Induction in Pharbitis Cotyledons Affected by Polyamines and Ethylene

  • Jueson Maeng
    • Journal of Plant Biology
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    • v.38 no.3
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    • pp.227-234
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    • 1995
  • Exogenous putrescine of 0.5 mM or higher concentratons applied during a 16 h inductive dark period could elevate putrescine content in cotyledons of Pharbitis nil Choisy cv. Violet, a short-day plant, resulting in complete blocking of photoperiodic floral induction. Titers of putrescine, spermidine and spermine in the cotyledons were traced throughout a 16 h dark period. While non-induced cotyledons under continous light slightly increased levels of polyamines, induced tissue maintaiend its putrescine, spermidine and spermine levels as low as 66.4%, 60.9% and 84.9% of non-induced levels respecitvely. Endogenous polyamines kept at lower levels in the inductive dark period were found to upsurge by a night break treatment of 10 min light in the middle of the dark and consequently the inductive dark effect was canceled. Elevation of polyamine titers could also be induced by 100 $\mu$L/L ethylene treatment which completely suppressed floral induction. Compared to untreated cotyledons, ehtylene-treated tissues increased putrescine content by as much as 136.5% in 12 h and spermidine level by up to 130.1% in 8 h. Ethylene-treated cotyledons not only increased endogenous polyamine content but also liberate ethylene in the second half of the inductive dark period accumulating up to three to fourfold level supporting a hypothesis that ethylene-treated tissues are stimulated to produce ethylene which in turn accelerates polyamine biosynthesis in the tissues. It is postulated that substantially low polyamine titers in the inductive dark period would be one of the necessary factors controlling photoperiodic induction of flowering in Pharbitis nil and the inhibitory effects of night break and exogenous ethylene treatment may be atributed to their action to stimulate endogenous polyamine production.

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A Study on the Ignition Induction Time and Temperature Distribution at Spontaneous Ignition of Activated Carbon (활성탄의 자연발화에 있어서 발화유도시간과 온도분포에 관한 연구)

  • 최재욱;김상렬;이상록;최광재
    • Journal of the Korean Society of Safety
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    • v.8 no.3
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    • pp.44-49
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    • 1993
  • The spontaneous ignition induction time and temperature distribution were observed by performing experiments for granulated activated carbon. As the results of the experiments at the same amplitude, the critical spontaneous ignition temperature was decreased with increase of the time period, while, the ignition induction time was increased with the increase of the time period. The critical spontaneous ignition temperature was decreased with the increase of the amplitude for the shorter period. The temperature distribution of the sample showed the highest around ignition-point at center of the vessel and after ignition the highest temperature was moved toward surface of the vessel.

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A investigation on the responses of conductive structures of Korean Peninsula using EM modeling

  • Yang, Jun-Mo;Oh, Seok-Hoon;Lee, Duk-Kee;Kwon, Byung-Doo;Youn, Yong-Hoon
    • 한국지구과학회:학술대회논문집
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    • 2004.02a
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    • pp.52-57
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    • 2004
  • Korean Peninsula located between Japan and China where earthquakes frequently occur, have little geophysical observation despite its tectonic importance. This study suggests the inland conductive structures inferred from GDS data measured in Korean Peninsula and try to interpret induction arrows quantitatively with the aid of 2- and 3-D geomagnetic induction modeling. Ogcheon Belt (OCB) and Imjin River Belt (IRB) are regarded as main conductive structures in Korea Peninsula, the induction arrows for the period of 60 minutes show very weak anomaly due to sea effect, which is supported by the results of 3-modeling also. However, for the period of 10 minutes, induction arrows at YIN and ICHN show anomalous patterns considered as the effect of IRB in spite of sea effect. The results of 2-D modeling which simplify geological situations provide overall information on IRB

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Time Delay Compensation for Output Voltage Vector Selection in Direct Torque Control of Induction Machine (유도전동기의 직접토크제어 시스템에서 출력전압벡터선정을 위한 시간지연의 보상)

  • 최병태;박철우;권우현
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.8
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    • pp.632-639
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    • 2003
  • This paper proposes a simple compensation scheme for the time delay caused by measurement, calculation and selection of voltage vector in Direct Torque Control (DTC) of an induction motor. In general scheme, it is difficult to know the exact delay time, furthermore the delay time can be varied by program routines for calculation and processing of measured data. In this proposed scheme, by applying voltage vector at the beginning of next sampling period, a fixed delay time is achieved and its compensation becomes much simpler. Furthermore, with the simple compensation algorithm, an improved performance can be achieved by shortening sampling period. Experimental results prove the feasibility of the proposed scheme in induction motor control.

Oxidation Stability of Fish Oil Containing Commercially Available Antioxidants (상업용 천연 항산화제의 사용에 다른 어유의 산화 안정성 연구)

  • Jang Ji-Sun;Lee Yun-Hee;Hong Jang-Hwan;Lee Ki-Teak
    • Food Science and Preservation
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    • v.13 no.1
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    • pp.66-70
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    • 2006
  • The effects of commercially available antioxidants in fish oil were studied. Induction period of fish oil was determined from the oxidation curve by rancin\mat. The longest Induction period was observed with catechin (1,000 ppm). Among the rosemary extracts (Antox1, Antox2, Antox3), the most effective antioxidant effect was observed with Antox3 even though higher amount (5,000 ppm) was needed compared to catechin. Compared to oder of control, catechin rather than Antox3 did not affect much the odor changes. When ascorbic palmitate, vitamin C, gallic acid, EDTA, citric acid, or propyl gallate as a synergist were added with catechin (500 ppm), vitamin C and ascorbic palmitate prolonged the induction period significantly. This effect was also observed with Antox3 (1,000 ppm). Among all combinations of catechin (500 ppm) and Antox3 (1,000 ppm) with synergists, the longest Induction period was obtained from Antox3 with vitamin C (200 ppm), suggesting that this combination is most effective combination for retarding the oxidation in fish oil.

An Improved Predictive Control of an Induction Machine fed by a Matrix Converter for Torque Ripple Reduction (토크 리플 저감을 위한 매트릭스 컨버터 구동 유도 전동기의 향상된 예측 제어 기법)

  • Lee, Eunsil;Choi, Woo Jin;Lee, Kyo-Beum
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.7
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    • pp.662-668
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    • 2015
  • This paper presents an improved predictive control of an induction machine fed by a matrix converter using N-switching vectors as the control action during a complete sampling period of the controller. The conventional model predictive control scheme based matrix converter uses a single switching vector over the same period which introduces high torque ripple. The proposed switching scheme for a matrix converter based model predictive control of an induction machine drive selects the appropriate switching vectors for control of electromagnetic torque with small variations of the stator flux. The proposed method can reduce the ripple of the electrical variables by selecting the switching state as well as the method used in the space vector modulation techniques. Simulation results are presented to verify the effectiveness of the improved predictive control strategy for induction machine fed by a matrix converter.

1981年度 韓國動物學會 秋季學術大會 特別講演 要旨: Resistance to Carcinogens at Early Developmental Stages and the Latent Period of Induced Neoplasms

  • 근등종평
    • The Korean Journal of Zoology
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    • v.25 no.1
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    • pp.29-29
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    • 1982
  • Carcinogenesis is extremely complex. Therefore, it is paradoxical but nonetheless important in cancer research if, in an animal whose parental strains are normally sensitive to cancer induction, we could find mutant strains which are resistant to various carcinogens as a result of mutations in one or two genes. No such mutants have been reported so far as I am aware but we do know that at early stages in their development, fish, mice, and humans are highly resistant to cancer induction by chemicals and radiation. I will give a brief overview of the stage-dependent resistance of fish, mice and humans to cancer induction and discuss the stem-cell mutation theory to explain the cancer-resistant stages. Finally, the latent period of induced neoplasms will be discussed in relation to the stem-cell mutation theory.

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Anesthetic and Cardiopulmonary Effects of Propofol as Infusion and Induction Anesthesia in Dogs (개에서 주사 및 도입마취제로서 Propofol의 마취효과 및 심폐기능에 미치는 영향)

  • Yoo, Jun-ho;Lee, Chung-ho;Kim, Wan-Hee;Nam, Tchi-chou;Kweon, Oh-kyeong
    • Korean Journal of Veterinary Research
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    • v.42 no.1
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    • pp.123-130
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    • 2002
  • To investigate the cardiopulmonary and anesthetic effects of propofol in dogs, experimental dogs were randomly divided into 4 groups (propofol infusion anesthesia, P/INF, propofol intermittent anesthesia, P/INTER, propofol induction anesthesia, P/ISO, thiopental Na induction anesthesia, T/ISO) and monitored analgesic and anesthetic effects, recovery time, body temperature, heart rate, mean arterial pressure, respiratory rate, systolic and diastolic pressure. In all groups, apnea was not observed. In the P/INF group, the respiratory rate(RR) was slightly decreased, but in the P/INTER group, RR was increased and shallowing. In the groups of P/ISO and T/ISO, the respiratory rate was decreased. Heart rate(HR) was increased after induction anesthesia in all groups, but gradually decreased. Mean arterial pressure(MAP) was decreased after injection anesthesia in the groups of P/INF and P/INTER. In the groups of P/ISO and T/ISO, however, MAP was slightly increased. Systolic and diastolic arterial pressure were gradually decreased after induction anesthesia, but not significantly. In the groups of P/INF and P/ISO, recovery time was shorter than the groups of P/INTER and T/ISO. In all groups, body temperature of animals was decreased gradually according to time but no significant changes were observed. Propofol injection doesn't make the complete loss of responses of animals, especially, in the P/INTER group. In the P/INF group, deep pain was present until the end of anesthetic period. During recovery period, any other side effects except incoordination were not monitored. The present study suggested that infusion anesthesia was superior to intermittent anesthesia as injection anesthetic agent, and propofol was better than thiopental Na as induction anesthetic agent.

Oxidative Stability of Perilla oil by Storage Temperature (저장온도에 따른 들깨기름의 산화 안전성)

  • 백숙은
    • Journal of the East Asian Society of Dietary Life
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    • v.4 no.3
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    • pp.97-102
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    • 1994
  • The oxidative stability of perilla oil were examined by measuring peroxide value. The induction period of perilla oil for each storage temperature was measured by POV and indicated that it was 80 days for 45$^{\circ}C$, 22.5 days for 65$^{\circ}C$, 9.5 days for 85$^{\circ}C$ and 5 days for 105$^{\circ}C$ respectively. Also, the induction period of the perilla oil with different concentration of ginger powder at 85$^{\circ}C$was studied and has been found that 9.4 days for 6% ginger powder, 11.9 days for 4% and 11days for 2% ginger power. The relative antioxidant effectiveness of ginger power was 99% for 6% ginger power, 125% for 4% ginger power, 122% for 2% ginger power. The induction period of perilla oil with gingerol at 85$^{\circ}C$ was 13.5days for 2% crude gingerol, 11.7days for 0.2% crude gingerol and 12.0 days for 0.02% BHT. The elativi antroxidant effectiveness of perilla oil gingerol at 85$^{\circ}C$was 142% for 2% crude gingerol, 123% for 0.2% crude gingerol, 126% for 0.02% BHT.

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