• 제목/요약/키워드: induction periods

검색결과 120건 처리시간 0.027초

우드펠릿의 저장량에 따른 발화온도 및 발화유도시간에 관한 연구 (A Study on the Ignition Temperature and Ignition Induction Time According to Storage Amount of Wood Pellets)

  • 김형석;최유정;김정훈;정필훈;최재욱
    • 한국화재소방학회논문지
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    • 제33권1호
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    • pp.7-14
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    • 2019
  • 우드펠릿은 화력발전소 및 화목 보일러의 연료로 많이 사용되고 있으나 발열량이 높은 우드펠릿을 장기간 보관 시 자연발화의 위험성이 있다. 본 연구에서는 시료 용기의 크기에 따라 유량의 변화에 따른 최소자연발화온도와 발화한계온도를 구하였으며, 발화한계온도를 이용하여 겉보기 활성화 에너지를 측정함으로써 우드펠릿의 발화 특성을 예측하였다. 겉보기 활성화 에너지는 190.224 kJ/mol을 구하였다. 용기에 저장된 시료량이 두꺼워질수록 시료 표면에서 중심까지의 열전달이 어려워 발화유도시간이 긴 것으로 나타났으며, 용기의 크기가 같을 경우 유량의 양이 많아 질수록 자연발화온도는 낮아졌다. 또한 시료용기가 커질수록 자연발화온도는 낮아지고 발화유도시간은 길어지는 것으로 나타났다.

광주기식물의 개화유도에 미치는 2-Chloroethylphosphonic Acid(Ethephon)의 효과에 관한 연구 I. Ethephon에 의한 Lemna perpusilla 6746 개화억제 (Studies on the Effect of 2-Chloroethylphosphonic Acid (Ethephon) on the Floral Induction in Photoperiodic Plants)

  • 맹주선
    • Journal of Plant Biology
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    • 제20권2호
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    • pp.77-82
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    • 1977
  • The inhibiotory effect of ethphon on the flowering in Lemna perpusilla 6746 was shown to be related to sucrose concentrations and dilution factors of Hutner's medium. When grown in 1/10-strength Hutner's medium under 10(14) cycles, the plants have been completely inhibited in the floral induction by ethephon (>5ppm) in the presence of sucrose (>20 mM) in the meduim. However, in a less diluted Hutner's medium (1/2-strength), the inhibition of flowering by ethephon was observed to be partially diminished by sucrose at a high concentration (30mM), while a low concentration of sucrose enhanced the inhibitory effect of ethephon in flowering. As inductive dark periodswere extended, the effects of both compounds were partially nullified. Since no significant amount of ethylene possibly released in ethephon decomposition in the medium was detected, the inhibitory effect of ethephon in flowering was postulated to be exerted only through ethylene production within the plants. Plants were incubated in 10 ppm ethephon-containing medium during either dark or light periods, singly or periodically. The most effective single treatment with ethephon was observed during the 4th dark period, when formation of floral stimulus was assumed to be completed beyond a critical level. This postulation can be partially supported by a fact that the plants should be exposed to at least more than four consecutive 10(14) cycles for flowering.

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Fast Switching Direct Torque Control Using a Single DC-link Current Sensor

  • Wang, Wei;Cheng, Ming;Wang, Zheng;Zhang, Bangfu
    • Journal of Power Electronics
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    • 제12권6호
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    • pp.895-903
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    • 2012
  • This paper presents a fast switching direct torque control (FS-DTC) using only a single DC-link current sensor. In FS-DTC, six new active voltage complex space vectors (CSVs) are synthesized by the conventional active voltage space vectors (SVs). The corresponding sectors are rotated in the anticlockwise direction by 30 degrees. A selection table is defined to select the CSVs. Based on the "Different Phase Mode", the output sequence of the selected CSV is optimized. Accordingly, a reconstruction method is proposed to acquire the phase currents. The core of the FS-DTC is that all of the three phase currents can be reliably reconstructed during every two sampling periods, which is the result of the fast switching between different phases. The errors between the reconstructed and actual currents are strictly limited in one sampling period. The FS-DTC has the advantages of the standard DTC scheme such as simple structure, quick torque response and robustness. As can be seen in the analysis, the FS-DTC can be thought of as an equivalent standard DTC scheme with 86.6% of the maximum speed, 173.2% of the torque ripple, and 115% of the response time of the torque. Based on a dSPACE DS1103 controller, the FS-DTC is implemented in an induction machine drive system. The results verify the effectiveness of the FS-DTC.

Comparison of Three Different Induction Regimens for Nasopharyngeal Cancer

  • Kertmen, Neyran;Aksoy, Sercan;Cengiz, Mustafa;Yazici, Gozde;Keskin, Ozge;Babacan, Taner;Sarici, Furkan;Akin, Serkan;Altundag, Kadri;Gullu, H. Ibrahim
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권1호
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    • pp.59-63
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    • 2015
  • Background: The standard treatment of local advanced nasopharyngeal cancer is chemoradiotherapy. There is a lack of data concerning induction therapy. In this study we retrospectively examined patients treated with induction therapy and chemoradiotherapy. Materials and Methods: Locally advanced nasopharyngeal cancer patients treated between 1996 and 2013 in our clinic were included in the study. Three different induction regimens were administered to our patients in different time periods. The regimen dosages were: CF regimen, cisplatin $50mg/m^2$ 1-2 days, fluorouracil $500mg/m^2$ 1-5 days; DC, docetaxel $75mg/m^2$ 1 day, cisplatin $75mg/m^2$ 1 day; and DCF, docetaxel $75mg/m^2$ 1 day, cisplatin $75mg/m^2$ 1 day, 5-Fu $750mg/m^2$ 1-5 days. Most of the patients were stage III (36.4%) and stage IV (51.7%). Results: Median follow-up time was 50 months (2-201 months). Three-year progression-free survival (PFS) was 79.3%, and 5-year PFS 72.4% in all patients. Three-year overall survival (OS) was 87.4% and 5-year OS 76% in all patients. In terms of induction therapies, 3-year OS was 96.5% in the DCF group, 86.6% in the DC group and 76.3% in the CF group (p=0.03). Conclusions: There was no significant differences in response rate and PFS between the three regimens. OS in the DCF group was significantly higher than in the other groups. However, this study was retrospective and limited toxicity data were available; the findings therefore need to be interpreted with care.

Antinociceptive Effect of Cyperi rhizoma and Corydalis tuber Extracts on Neuropathic Pain in Rats

  • Choi, Jae-Gyun;Kang, Suk-Yun;Kim, Jae-Min;Roh, Dae-Hyun;Yoon, Seo-Yeon;Park, Jin Bong;Lee, Jang-Hern;Kim, Hyun-Woo
    • The Korean Journal of Physiology and Pharmacology
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    • 제16권6호
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    • pp.387-392
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    • 2012
  • In this study, we examined the antinociceptive effect of Cyperi rhizoma (CR) and Corydalis tuber (CT) extracts using a chronic constriction injury-induced neuropathic pain rat model. After the ligation of sciatic nerve, neuropathic pain behavior such as mechanical allodynia and thermal hyperalgesia were rapidly induced and maintained for 1 month. Repeated treatment of CR or CT (per oral, 10 or 30 mg/kg, twice a day) was performed either in induction (day 0~5) or maintenance (day 14~19) period of neuropathic pain state. Treatment of CR or CT at doses of 30 mg/kg in the induction and maintenance periods significantly decreased the nerve injury-induced mechanical allodynia. In addition, CR and CT at doses of 10 or 30 mg/kg alleviated thermal heat hyperalgesia when they were treated in the maintenance period. Finally, CR or CT (30 mg/kg) treated during the induction period remarkably reduced the nerve injury-induced phosphorylation of NMDA receptor NR1 subunit (pNR1) in the spinal dorsal horn. Results of this study suggest that extracts from CR and CT may be useful to alleviate neuropathic pain.

SUCCESSIVE INDUCTION OF LACTATION IN CATTLE

  • Dabas, Y.P.S.;Sud, S.C.
    • Asian-Australasian Journal of Animal Sciences
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    • 제2권4호
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    • pp.571-574
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    • 1989
  • Five multiparous and four nulliparous cross-bred cows were administered s/c with oestradiol-$17{\beta}$ and progesterone 0.1 mg and 0.25 mg/kg. b.w./day for 7 days and 2 mg s/c twice daily of reserpine on days 9 to 12. Lactation was successfully induced in all animals for periods from 258 to 476 days. All animals were dried off for a minimum of 2 months. Subsequently, they were injected s/c with oestradiol valerate and hydroxyprogesterone caproate at 0.1 mg and 0.25 mg/kg. b.w./day on days 1 to 3 and 2 mg twice daily of reserpine on days 8 to 11. Lactation was successfully reinduced in all the cows for a period varying from 228 to 426 days.

교통량예측모형의 개발과 평가 (TRAFFIC-FLOW-PREDICTION SYSTEMS BASED ON UPSTREAM TRAFFIC)

  • 김창균
    • 대한교통학회:학술대회논문집
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    • 대한교통학회 1995년도 제27회 학술발표회
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    • pp.84-98
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    • 1995
  • Network-based model were developed to predict short term future traffic volume based on current traffic, historical average, and upstream traffic. It is presumed that upstream traffic volume can be used to predict the downstream traffic in a specific time period. Three models were developed for traffic flow prediction; a combination of historical average and upstream traffic, a combination of current traffic and upstream traffic, and a combination of all three variables. The three models were evaluated using regression analysis. The third model is found to provide the best prediction for the analyzed data. In order to balance the variables appropriately according to the present traffic condition, a heuristic adaptive weighting system is devised based on the relationships between the beginning period of prediction and the previous periods. The developed models were applied to 15-minute freeway data obtained by regular induction loop detectors. The prediction models were shown to be capable of producing reliable and accurate forecasts under congested traffic condition. The prediction systems perform better in the 15-minute range than in the ranges of 30-to 45-minute. It is also found that the combined models usually produce more consistent forecasts than the historical average.

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인삼중의 항산화물질에 관한 연구;제2보 : 인삼의 석유에테르 추출물의 항산화작용 (Studies on the Antioxidant Substances in Panax Ginseng Roots;II. The Antioxidant Activity of Petroleum Ether Extact of Panax Ginseng Roots)

  • 백태홍;홍정태
    • 한국응용과학기술학회지
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    • 제3권1호
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    • pp.39-42
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    • 1986
  • The antioxidant activity of petroleum ether extract of Panax ginseng roots in the oxidation of mixed methyl esters of unsaturated fatty acids(MEUFA) was investigated in vitro. The petroleum ether extract of panax ginseng roots showed the antioxidant activity and inhibited the weight gain in the autoxidation of MEUFA. And the induction periods in the autoxidation of MEUFA were related to te addition concentrations of petroleum ether extact. The antioxidant effect of petroleum ether extract on the autoxidation of MEUFA was caused by the protective formation of lipid peroxides and carbonyl compounds. From the results obtained, it was confirmed that petroleum ether extract of panax ginseng roots contained antioxidant substances.

대두유의 자동산화 및 가열산화에 미치는 정향추출물의 항산화 효과 (Effects of Clove Extracts on the Autoxidation and Thermal Oxidation of Soybean Oil)

  • 박상일;손종연
    • 한국식품조리과학회지
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    • 제20권1호
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    • pp.81-85
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    • 2004
  • This study was conducted to investigate the antioxidant activities of clove extracts in water, methanol and ether. The clove extracts, BHA and ${\alpha}$-tocopherol were added to each oil at a level of 200 ppm. The activities of the substrate oils and controls were tested under autoxidation and thermal oxidation conditions. The degree of the effects of the antioxidant activities under autoxidation condition were in the following order; ether extract 〉 methanol extract 〉BHA 〉 ${\alpha}$-tocopherol 〉 water extract = control group. The induction periods of the control, water, methanol and ether extracts, and BHA and ${\alpha}$-tocopherol were 9.5, 9.6, 10.7 11.8, 10.4 and 9.7 days, respectively. Under thermal oxidation condition, the methanol extract showed stronger antioxidant activity than those of the water and ether extracts. The antioxidant activity of the methanol extract was attributed to ${\alpha}$-tocopherol and BHA.

Nutritional and Hormonal Regulation of Fatty Acid Synthase Gene Expression

  • Shin, Dong-Hoon;Kim, Byung-Yong;Hahm, Young-Tae;Kim, Eunki;Cho, Won-Dai
    • Preventive Nutrition and Food Science
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    • 제2권3호
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    • pp.246-249
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    • 1997
  • The maximum 30-fold level of fatty acid synthase (FAS) mRNA was achieved by 6hr after intraperitoneal injection of insulin. The kinetics and maximum effect of insulin were most evident on he 7.2 kb mRNA. In six hors after insulin administration there was about 100-fold increase in stead-state mRNA level. We observed a sharp decrease in 7.2kb mRNA by 8hr after insulin administation while there was no change in FAS mRNA content between the 6hr and 8hr-sampling periods. In contrast, a maximum induction of 4-fold was shown in the level of 5.1kb mRNA after insulin injection in streptozotocin-diabetic mice.

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