• Title/Summary/Keyword: Condition state variation

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TCSC Nonlinear Adaptive Damping Controller Design Based on RBF Neural Network to Enhance Power System Stability

  • Yao, Wei;Fang, Jiakun;Zhao, Ping;Liu, Shilin;Wen, Jinyu;Wang, Shaorong
    • Journal of Electrical Engineering and Technology
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    • v.8 no.2
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    • pp.252-261
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    • 2013
  • In this paper, a nonlinear adaptive damping controller based on radial basis function neural network (RBFNN), which can infinitely approximate to nonlinear system, is proposed for thyristor controlled series capacitor (TCSC). The proposed TCSC adaptive damping controller can not only have the characteristics of the conventional PID, but adjust the parameters of PID controller online using identified Jacobian information from RBFNN. Hence, it has strong adaptability to the variation of the system operating condition. The effectiveness of the proposed controller is tested on a two-machine five-bus power system and a four-machine two-area power system under different operating conditions in comparison with the lead-lag damping controller tuned by evolutionary algorithm (EA). Simulation results show that the proposed damping controller achieves good robust performance for damping the low frequency oscillations under different operating conditions and is superior to the lead-lag damping controller tuned by EA.

Calculation on Electronic State of $MnO_2$ Oxide Semiconductor with other initial spin conditions by First Principle Molecular Orbital Method (제1원리 분자궤도계산법에 의한 초기 spin 조건에 따른 $MnO_2$ 반도체의 전자상태 변화 계산)

  • Lee, Dong-Yoon;Kim, Bong-Seo;Song, Jae-Sung;Kim, Hyun-Sik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.11a
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    • pp.148-151
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    • 2003
  • The spin density of ${\beta}-MnO_2$ structure was theoretically investigated by $DV-X_{\alpha}$ (the discrete variation $X{\alpha}$) method, which is a sort of the first principle molecular orbital method using Hatre-Fock-Slater approximation. The used cluster model was $[Mn_{14}O_{56}]^{-52}$. The ${\beta}-MnO_2$ is a paramagnetic oxide semiconductor material having the energy band gap of 0.18 eV and an 3 loan-pair electrons in the 3d orbital of an cation. This material exhibits spin-only magnetism and has the magnetic ordering temperature of 94 K. Below this temperature its magnetism appears as antiferromagnetism. The calculations of electronic state showed that if the initial spin condition of input parameters changed, the magnetic state changed from paramagnetic to antiferromagnetic. When d orbital of all Mn atoms in cluster had same initial spin state as only up spin, paramagnetic spin density distribution appeared by the calculation. On the other way, d orbital had alternately changed spin state along special direction the resulted spin distribution showed antiferromagnetism.

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Study of runout-motion in body physical techniques: physical index and sensory index

  • Kim, Jeong-lae;Shin, Kyu-ok
    • International journal of advanced smart convergence
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    • v.5 no.3
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    • pp.56-60
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    • 2016
  • Body physical technique is to pursuit the dynamic motion by the physical index(PI) and sensory index(SI) on the physical body function. Function of the physical body by the motor condition is organized the dynamic physical system. For the physical motion of signal, we is defined a runout value of the body function by the physical index on the dynamic state. The concept of body physical index was identified the reference of physical index and sensory index by the body technique. As to detect a variation of the body physical technique-runout physical index(BPT-RPI) of the maximum and average and minimum in terms of physical motion, and the dynamic sensory value that was a runout function of the vision variation of the $Vi-{\xi}_{MAX-AVG-MIN}$ with $2.53{\pm}4.85$ units, that was a runout function of the vestibular variation of the $Ve-{\xi}_{MAX-AVG-MIN}$ with ($-0.69{\pm}2.32$)units, that was a runout function of the somatosensory variation of the $So-{\xi}_{MAX-AVG-MIN}$ with ($-1.43{\pm}-1.36$) units. The dynamic physical motion will be to confirm at the variable function of the runout motion for the body function values of dynamic physical index on the BPT-RPI that was identified an evaluation of the physical sensory function by the dynamic physical system. Runout body system was mentioned of a physical body situation by the mild moving and was refer a runout data of dynamic physical nervous index.

Expression Patterns of Transposable Elements in Magnaporthe oryzae under Diverse Developmental and Environmental Conditions

  • Chung, Hyunjung;Kang, Seogchan;Lee, Yong-Hwan;Park, Sook-Young
    • Research in Plant Disease
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    • v.26 no.1
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    • pp.38-43
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    • 2020
  • The genome of the rice blast fungus Magnaporthe oryzae contains several types of transposable elements (TEs), and some TEs cause genetic variation that allows M. oryzae to evade host detection. We studied how five abundant TEs in rice pathogens, Pot3, Pot2, MAGGY, Line-like element (MGL) and Mg-SINE, are expressed under diverse conditions related to growth, development, and stress. Expression of Pot3 and Pot2 was activated in germinated conidia and mycelia treated with tricyclazole. Retrotransposon MAGGY was highly expressed in appressoria and tricyclazole-treated mycelia. MAGGY and Pot2 were also activated during the early and late stages of perithecia development. MGL was up-regulated in conidia and during conidial germination but not during appressorium formation. No noticeable expression of Mg-SINE was observed under most conditions. Our results should help investigate if and how condition-specific expressions of some TEs contribute to the biology and evolution of M. oryzae.

Studies on the Thermal Insulation Effect of Bedding (II) - Thermal Insulation Effect of Quilt - (이부자리의 보온력에 관한 연구(II) -이불의 보온력 -)

  • Lee Song-Ja;Sung Su-Kwang
    • Journal of the Korean Society of Clothing and Textiles
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    • v.16 no.4 s.44
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    • pp.349-355
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    • 1992
  • Comfortable sleeping largely depends on human mental state, physical condition, the temper. ature and humidity in bedrooms, and qualities of quilt and bedcover. Of the qualities of quilt, thermal insulation effect plays the most important role in keeping bedroom in ample temperature and preventing human body from giving off heat. In the present study, which is a sequel study to research on the thermal insulation effect, the real-size quilts with the following items of filling materials in them are designed to research on the variation of each item, and to measure the effect of the weight variation in inner covers on the thermal insulation effect of quilts, the results are as follows: 1. The coefficient between the weight of filling materials and the thermal insulation effect of quilt is shown to be a significant $0.91\~0.97$. 2. The thermal insulation effect of the quilts with in size of $0.5\;Kg/m^{2}$ is surveyed to be high in order down > polyester > cotton > wool. 3. The effect of the texture of inner covers on the thermal insulation effect of quilt is shown to be ignorably low. 4. The weight of filling materials is shown to be in correlation with the thermal insulation effect of quilts, and the estimated regression line has been obtained.

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A Mock Running And Transient State Test of Propulsion VVVF Inverter for Electric Locomotive using A Inertia Load (관성부하를 이용한 전동차 추진용 VVVF 인버터의 모의주행 및 과도상태시험)

  • 정만규;서광덕
    • The Transactions of the Korean Institute of Power Electronics
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    • v.4 no.6
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    • pp.491-499
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    • 1999
  • This paper is on the high perfonnance propulsion IGBT VVVF inverter adopted new technique for railways. To prove the high performance and stabilit~r of traction, running tests are carried out under the simulated condition alike real field. The tests are perfonned on not only a steady states but also a transient states such a as input voltage variation using inertia load equivalent to 160tons train. The vector control technique is a adopted to improve traction for 4 motors. The low switching synchronous PW1\l method based on a space v voltage vector modulation is pro\XlSed as the optimal method for propulsion system railway. The output voltage l is controlled continuously to six step by prolxlsed ovennodu]ation technique without sudden torque variation.

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Mineral Concentration in Blood of Grazing Goats and Some Forage in Lahar-Laden Area of Central Luzon, Philippines

  • Orden, E.A.;Serra, A.B.;Serra, S.D.;Aganon, C.P.;Cruz, E.M.;Cruz, L.C.;Fujihara, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.3
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    • pp.422-428
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    • 1999
  • The mineral status of native goats and forage species, namely; Cynodon plectostachyus, Pennisetum purpureum. Eleusine indica, Cynodon dactylon, Calopogonium muconoides, Centrosema pubescens, Leucaena leococephala, and Mimosa pudica in lahar affected areas of Concepcion, Tarlac, Philippines were determined. Forage and blood samples were collected six times in 1996-97, and analyzed for calcium, phosphorus, magnesium, sulfur, copper, iron, molybdenum, selenium, and zinc. Forage calcium and sulfur are non-limiting. Most species had low phosphorus, copper and selenium, while some had magnesium and zinc levels lower than the critical limit because of low mineral content and high percolation rate of lahar deposits. Iron and molybdenum were in excess. The effect of seasonal variation was observed only in copper, sulfur and iron. Average blood mineral concentration of the animals was above critical limit, but there were no significant differences between seasons. All the animals had plasma phosphorus and magnesium above critical level; but 20 % had low copper, zinc and selenium especially in dry season possibly due to insufficient amount of these elements and excessive molybdenum and iron in most forage. Conversely, calcium in forage was high; but 40 % of the animals had low plasma calcium concentration. Although no clinical signs of mineral deficiencies were observed, supplemental feeding would be important since the condition of the pasture in lahar-laden areas is not expected to improve in the next five years. Intensified use of L. leucocephala with better mineral profile would be ideal.

Self-healing capacity of damaged rock salt with different initial damage

  • Chen, Jie;Kang, Yanfei;Liu, Wei;Fan, Jinyang;Jiang, Deyi;Chemenda, Alexandre
    • Geomechanics and Engineering
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    • v.15 no.1
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    • pp.615-620
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    • 2018
  • In order to analyze the healing effectiveness of rock salt cracks affected by the applied stresses and time, we used the ultrasonic technology to monitor the ultrasonic pulse velocity (UPV) variations for different initial stress-damaged rock salts during self-healing experiments. The self-healing experiments were to create different conditions to improve the microcracks closure or recrystallized, which the self-healing effect of damaged salt specimens were analyzed during the recovery period about 30 days. We found that: The ultrasonic pulse velocity of the damaged rock salts increases rapidly during the first 9 days recovery, and the values gradually increase to reach constant values after 30 days. The damaged value and the healed value were identified based on the variation of the wave velocity. The damaged values of the specimens that are subject to higher initial damage stress are still keeping in large after 30 days recovery under the same recovery condition It is interesting that the damage and the healing were not in the linear relationship, and there also existed a damage threshold for salt cracks healing ability. When the damage degree is less than the threshold, the self-healing ratio of rock salt is increased with the increase in damage degree. However, while the damage degree exceeds the threshold, the self-healing ratio is decreased with the increase in damage.

Physicochemical properties and energy content of yellow dent corn from different climatic origins in growing pigs

  • Dong, Wenxuan;Li, Juntao;Li, Zhongchao;Zhang, Shuo;Li, Xiaozhen;Yang, Chundi;Liu, Ling;Zhang, Shuai
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.11
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    • pp.1787-1796
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    • 2020
  • Objective: The objective of this study was to determine the digestible energy (DE) and metabolizable energy (ME) of yellow dent corn sourced from different meteorological origins fed to growing pigs and develop equations to predict the DE and ME of yellow dent corn from southwestern China. Methods: Sixty crossbred barrows were allotted to 20 treatments in a triplicate 20×2 incomplete Latin square design with 3 replicated pigs per dietary treatment during 2 consecutive periods. Each period lasted for 12 days, and total feces and urine during the last 5 days of each period were collected to calculate the energy contents. Results: On dry matter (DM) basis, the DE and ME in 20 corn grain samples ranged from 15.38 to 16.78 MJ/kg and from 14.93 to 16.16 MJ/kg, respectively. Selected best-fit prediction equations for DE and ME (MJ/kg DM basis) for yellow dent corn (n = 16) sourced from southwestern China were as follows: DE = 28.58-(0.12×% hemicellulose)+(0.35×% ether extract)-(0.83×MJ/kg gross energy)+(0.20×% crude protein)+(0.49×% ash); ME = 30.42-(0.11×% hemicellulose)+(0.31×% ether extract)-(0.81×MJ/kg gross energy). Conclusion: Our results indicated that the chemical compositions, but not the meteorological conditions or physical characteristics could explain the variation of energy contents in yellow dent corn sourced from southwestern China fed to growing pigs.

The Seepage Behaviour and Stability of Extension Embankment by Unsteady State Seepage (비정상침투에 의한 증축제체의 침투거동과 안정성)

  • Shin, Bang-Woong;Bae, Woo-Seok;Lee, Jong-Kyu;Kang, Jong-Beom
    • Journal of the Korean GEO-environmental Society
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    • v.2 no.1
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    • pp.57-65
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    • 2001
  • In this study, the seepage behavior and the stability of the extension embankment were estimated for three cases the permeability coefficient of an extension part and the rising velocity due to the rainfall of flood period. In parallel flow condition, the unstability of the slope due to embankment erosion was examined by analyzing the variation of seepage line by the seepage modeling tests and FEM analysis, and the stability of the embankment slope accompanied by the sudden rise of the water level after the flood. The seepage behavior of extension embankment indicates that the larger permeability of the extension part the longer initial seepage distance, and the exit point from embankment slope is gradually increased, and then shows unstable seepage behavior that occurs a partial collapse as safety factor decreases with time. It is because of the increment of exit points due to variation of seepage line and rising velocities of water level. Also, the collapse aspect of embankment slope shows that the increment rising velocities of water level causes the increment collapse height and depth.

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