• Title/Summary/Keyword: induction periods

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Analysis of Induction Motor-pump System Supplied by a Photovoltaic Generator for Agricultural Irrigation in Southeastern Anatolian Region of Turkey

  • Gumus, Bilal;Yakut, Yurdagul Bentesen
    • Journal of Electrical Engineering and Technology
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    • v.10 no.3
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    • pp.777-785
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    • 2015
  • In agricultural systems, significant amount of energy is consumed during irrigation periods. Therefore operating irrigation systems with electrical energy produced by solar energy is very important. It is be possible to operate irrigation systems which have small-pump power like drip-irrigation with electrical energy produced by solar energy. Electrical energy produced by photovoltaic panels can vary from the estimated value due to environmental factors. Consequently analysis of a real system's performance is important. Thus, more correct projections can be made for the systems which will be designed. In this study, induction motor-pump mechanism for drip-irrigation system is operated with photovoltaic generator. Solar energy capacity of the established system is evaluated by measurements in irrigation periods. By means of simulations, power values produced by system and gained from the actual system are compared. Additionally the performance of induction motor is analyzed with the help of the driver system that increases the efficiency and controls the motor. As regards of results, design values of the drip-irrigation systems fed with solar energy in Southeastern Anatolian Regions of Turkey are obtained. Performance results of induction motor controlled with driver are also provided.

The effect of squalene and tocopherols on their autooxidation of bean oil (콩기름의 자동산화에 미치는 스쿠알렌과 토코페롤의 합산화 효과)

  • 김대봉;오문헌
    • The Korean Journal of Food And Nutrition
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    • v.9 no.3
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    • pp.331-335
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    • 1996
  • In this study, the attempts were made to Investigate the effect of squalene (200 ppm) on the autooxidation of soybean oil The effect of mixed tocopherols (200 ppm) was also studied In the same way and the results of the study were compared with those of squalene. A put of a commercial soybean oil was stored at 45.0$\pm$0.5t for their autooxidation. The extent of the autooxidation was estimated from the changes of the peroxide value and % conjugated dienoic acid content of the ell substrates The results of the autooxidation, squalene In the soybean oil substrate showed antioxidant activity but the activity was weaker than that of mixed-tocopherols nth the same concentration. The induction periods of the control and substrates with the same concentration. The Induction periods of the control and substrates with squalene and mixed-tocopherols were 448.5 504.9 and 668.9 hours, respectively. Time required to Tech a POV of 30meq/kg oil.

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Differential Expression of Th1- and Th2- Type Cytokines in Peripheral Blood Mononuclear Cells of Murrah Buffalo (Bubalus Bubalis) on TLR2 Induction by B. Subtilis Peptidoglycan

  • Shah, Syed M.;Ravi Kumar, G.V.P.P.S.;Brah, G.S.;Santra, Lakshman;Pawar, Hitesh
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.7
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    • pp.1021-1028
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    • 2012
  • Peripheral blood mononuclear cells (PBMCs) discriminate microbial pathogens and induce T-cell responses of appropriate effector phenotype accordingly. Toll-like receptors (TLRs), in part, mediate this microbial recognition and differentiation while the development of T-cell effector functions critically depends on the release of Th1- or Th2- type cytokines. In the present study, buffalo PBMCs were stimulated under in vitro culture conditions by Bacillus subtilis cell wall petidoglycan, a TLR2 ligand, in a dose- and time- dependent manner. The expression of TLR2 as well as the subsequent differential induction of the Th1 and Th2 type cytokines was measured. Stimulation was analyzed across five doses of peptidoglycan ($10{\mu}g/ml$, $20{\mu}g/ml$, $30{\mu}g/ml$, $40{\mu}g/ml$ and $50{\mu}g/ml$) for 3 h, 12 h, 24 h and 36 h incubation periods. We observed the induction of TLR2 expression in a dose- and time-dependent manner and the peptidoglycan induced tolerance beyond $30{\mu}g/ml$ dose at all incubation periods. The correlation between peptidoglycan stimulation and TLR2 induction was found positive at all doses and for all incubation periods. Increased production of all the cytokines was observed at low doses for 3 h incubation, but the expression of IL-4 was relatively higher than IL-12 at the higher antigen doses, indicating tailoring towards Th2 response. At 12 h incubation, there was a pronounced decrease in IL-4 and IL-10 expression relative to IL-12 in a dose- dependent manner, indicating skewing to Th1 polarization. The expression of IL-12 was highest for all doses across all the incubation intervals at 24 h incubation, indicating Th1 polarization. The relative expression of TNF-${\alpha}$ and IFN-${\gamma}$ was also higher while that of IL-4 and IL-10 showed a decrease. For 36 h incubation, at low doses, relative increase in the expression of IL-4 and IL-10 was observed which decreased at higher doses, as did the expression of all other cytokines. The exhaustion of cytokine production at 36 h indicated that PBMCs became refractory to further stimulation. It can be concluded from this study that the cytokine response to sPGN initially was of Th2 type which skews, more pronouncedly, to Th1 type with time till the cells become refractory to further stimulation.

Antioxidant Activity of Maltol, Kojic Acid, Levulinic Acid, Furfural, 5- Hydroxymethyl Furfural, and Pyrazine (Maltol, Kojic Acid, Levulinic Acid, Furfural, 5-Hydroxymethyl Furfural과 Pyrazine의 항산화작용)

  • Yi, Bum-Hong;Kim, Dong-Hoon
    • Korean Journal of Food Science and Technology
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    • v.14 no.3
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    • pp.265-270
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    • 1982
  • An attempt was made to investigate the antioxidant activity of maltol, kojic acid, levulinic acid, furfural, 5-hydroxymethyl furfural (5-HMF), and pyrazine which had been known to be important intermediates of Maillard browning reactions. The activity of these compounds was determined by comparing induction periods of soybean oil substrates containing each compound at a 0.01M level with that of a control. The induction period was arbitrarily taken as the time in hours for a substrate to reach a peroxide value of 60meq/kg oil. The substrates and control were stored at $45.0{\pm}1.0^{\circ}C$ for 30 days. The induction periods of the control, kojic acid, furfural, 5-HMF, maltol, levulinic acid, and pyrazine were respectively 468, 592, 510, 498, 486, 450, and 402 hours. Kojic acid demonstrated considerable antioxidant activity, whereas furfural, 5-HMF, and maltol showed weak activivity. Pyrazine and levulinic acid showed pro-oxidant activity. Although the prooxidant activity of pyrazine seemed definite, that of levulinic acid appeared very weak.

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Effect of Naturally Occurring Antioxidants on the Oxidative Stability of Fish Oil (천연 산화방지제가 어유의 산화안정성에 미치는 영향)

  • Han, Dae-Seok;Yi, Ock-Sook;Shin, Hyun-Kyung
    • Korean Journal of Food Science and Technology
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    • v.23 no.4
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    • pp.433-436
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    • 1991
  • Natural compounds which could improve the oxidative stability of fish oil was screened from spices, herbs and naturally occurring antioxidants. Induction period of fish oil determined from oxidation curve by Rancimat ($80^{\circ}C$) was hardly affected with the addition of water-soluble and lipid-soluble fractions of garlic, leek, sesame leave and orange peel, and of organic acids such as citric acid, EDTA and selenium. Caffeic acid, catechin, quercetin and gallic acid laurylester, however, could extend the induction periods by $2.2{\sim}3.8$ times with the addition level of 0.1%(w/w). Rosemary extract and sesamol have a marked effect in retarding oxidation of fish oil. For example, induction periods of the oil samples stabilized with 0.1 rosemary extract and 0.1 sesamol were 16.4 hr and 11.6 hr, respectively, as compared to 4.0 hr of a control. When rosemary extract was used in combination with ascorbic acid (0.02%) or 8-tocopherol (0.2%), induction period could be extended to ca. 28 hr due to the synergism.

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Wet Co-Oxidation of Quinoline and Phenol (퀴놀린-페놀 혼합용액의 습식산화)

  • Ryu, Sung Hun;Yoon, Wang-Lai;Suh, Il-Soon
    • Applied Chemistry for Engineering
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    • v.20 no.5
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    • pp.486-492
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    • 2009
  • Wet oxidations (WO) of quinoline in aqueous solution were carried out at $225^{\circ}C$ and $250^{\circ}C$. In the WO at $250^{\circ}C$, quinoline was degraded completely within 30 min and the reduction in total organic carbon (TOC) of 63% was achieved during 120 min. However, the rate of the reduction in TOC was only 13% within 240 min during the WO at $225^{\circ}C$. Nicotinic and acetic acid were found to be main intermediates formed during the oxidation of quinoline. With the addition of the homogeneous catalyst $CuSO_4$ or more easily oxidizable phenol, WOs of quinoline were also carried out under moderate conditions at $200^{\circ}C$. The catalytic WO with $CuSO_4$ of 0.20 g/L showed the destruction rates of quinoline and TOC comparable to those in the WO at $250^{\circ}C$. The WOs of quinoline-phenol mixture exhibited induction periods to degrade quinoline and phenol during which free radicals were produced to initiate WOs. With increasing initial concentrations of phenol at a given initial concentration of quinoline, the induction periods in the destructions of quinoline and phenol became shorter and the reduction in TOC increased from 60% to 75% during 180 min of the WOs. The reduction rate of an induction period decreased as increasing the initial concentration ratio of phenol to quinoline. On the other hand, phenol degradation in the WOs of quinoline-phenol mixtures required a longer induction period and proceeded slower compared to the case of the WO of phenol.

Studies on Inhibition Factors and the Role of Phytochrome in the Floral Induction in Short-day Plants (단일식물의 개화유도를 조절하는 개화억제요소의 규명과 Phytochrome의 역할에 관한 연구)

  • 맹주선
    • Journal of Plant Biology
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    • v.19 no.1
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    • pp.14-18
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    • 1976
  • Inhibition of flowering in Lemna perpusilla 6746 by 30 mM sucrose was reversed by the addition of acetylcholine (>$10^{-4}M) supplemented with 10^{-4}M$ ascorbic acid to 1/10-strength Hunter's growth medium. The reversible effect of acetylcholine was found to be greater at early stages of flowering than in the later period. Promotive effects of both acetylcholine ($10^{-3}M) and eserine(10^{-5}M$) on flowering in the short-day plant under various photoperiodic conditions were studied. It was indicated that the application decreased length of the critical dark period for the floral induction, and it was also shown that the endogenous status of acetylcholine was involved in the floral response which had a correlation with phytochrome. Interruption of inductive dark periods by red irradiation (1min) immediately followed by far-red light (1 min) completely inhibited flowering, while the addition of acetylcholine and eserine to the medium under the same condition slightly promoted flowering, indicating possible involvement of phytochrome system in acetylcholine activity for photoperiodic sensitivity of floral response in Lemna perpusilla 6746.

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A combined pathway of somatic embryogenesis and organogenesis to regenerate radiata pine plants

  • Montalban, I.A.;De Diego, N.;Igartua, E. Aguirre;Setien, A.;Moncalean, P.
    • Plant Biotechnology Reports
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    • v.5 no.2
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    • pp.177-186
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    • 2011
  • This study describes for the first time in Pinus genus a plant regeneration system via a combined pathway of somatic embryogenesis and organogenesis from immature seeds of radiata pine. Somatic embryos were obtained from embryogenic line 2162 of Pinus radiata D. Don on EDM basal medium containing $60{\mu}M$ ABA and 6% sucrose. The explants used for organogenesis experiments were either freshly collected somatic embryos or somatic embryos germinated for 1 week. Germination medium was half-strength LP medium, supplemented with 0.2% activated charcoal. Different induction periods and BA concentrations were assayed for shoot induction. After induction treatments, explants were elongated on the same medium used for germination stage. Rooting medium was quarter-strength LP medium supplemented with three different auxin treatments: $1.5mg\;L^{-1}$ 1-naphthalene acetic acid (NAA), $1.5mg\;L^{-1}$ indole-3-butyric acid (IBA) and $1mg\;L^{-1}$ IBA with $0.5mg\;L^{-1}$ NAA (MIX). The effect of the photon flux ($120mmol\;m^{-2}\;s^{-1}$ and darkness) in the first week of the explants in the rooting media was also tested. This methodology could offer an alternative to overcome some problems associated with somatic embryogenesis such as the seasonality of embryogenic tissue (ET) initiation or a low embryo production from the ET, a particularly important issue in the case of genetically transformed ETs.

Evaluation of Efficiency Uncertainty for Three-phase Induction Motor using Finite Element Analysis (유한요소 해석을 이용한 3상 유도전동기의 효율 불확도 평가)

  • Lee, Ho-Hyun;Park, Han-Seok;Jun, Hee-Deuk;Woo, Kyung-Il
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.66 no.4
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    • pp.163-168
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    • 2017
  • This paper presented an evaluation method for the efficiency uncertainty of a three-phase induction motor using finite element analysis. The motor efficiency in the finite element analysis is calculated by the loss separation method as in the actual test. In the process of evaluating the efficiency uncertainty, the difference between the finite element analysis and the actual test is the method of calculating the type-A / B standard uncertainty of the input quantity to estimate the efficiency and each losses. For the input quantities which can confirm the instantaneous values with respect to time, the type-A standard uncertainty in the finite element analysis is calculated from the RMS values or average values having separate periods in the steady state. And, the type-B standard uncertainty in the finite element analysis is assumed to be zero. Also, this paper compared and analyzed the efficiency uncertainty evaluated by the proposed method and the efficiency uncertainty through the actual test.

A Robust Control Scheme of Linear Induction Machine for Automatic Picking System Using Mass Estimation and Disturbance Force Observer (질량추정과 외란추력 관측기를 이용한 자동피킹 시스템 구동용 선형 유도모터의 강인제어 기법)

  • Choi, Jung-Hyun;Yoo, Dong-Sang;Kim, Kyeong-Hwa
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.4
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    • pp.62-72
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    • 2013
  • To operate an automatic picking system in distribution center with high precision and high dynamics, this paper presents a robust control scheme of a linear induction motor (LIM) using the mass estimation and disturbance force observer. The force disturbance which gives a direct influence on the control performance of LIM is estimated in real-time through the disturbance observer and compensated by a feedforward manner. To get a satisfactory performance even under the mass variation by reducing the disturbance force due to the mismatched mass during the speed transient such as the acceleration and deceleration periods, a mass estimation algorithm is proposed. A Simulink model for LIM is developed and the validity of the proposed scheme is verified through the comparative simulation studies using Matlab - Simulink.