• Title/Summary/Keyword: Growth control

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Study on the Growth and the Drought Resistance of Amorpha fructicosa under the Control of Water Supply (수분공급조절에 의한 족제비싸리의 생장과 내건성에 관한 연구)

  • Hong, Kyung-Hae;Kim, Woen
    • The Korean Journal of Ecology
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    • v.5 no.2_3
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    • pp.123-131
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    • 1982
  • The growth and the resistance of Amorpha fructicosa L. under water control was experimented in frames out of doors. The plant grew in a wagner's pot under water control. The soil moisture content was controlled at 5%, 10%, 15% and 20%. The growth of leaf, stem and root in the groups of 5% and 10% soil moisture content were different from values in the groups of 15% and 20%. The T/R ratio in the groups of 5% and 10% soil moisture content were different from the ratio in the groups of 15% and 20% soil moisture content. The T/R ratio of former was lower than the latter, but the C/F ratio of the former was higher than the latter. RGR and NAR of Amorpha fructicosa decreased in 5% and 10% soil moisture content but increased in 15% and 20% soil moisture content during growing period. The maximum values of RGR and NAR were respectively 0.089 and 0.080 at 20% soil moisture content. The highest value of LAR was 1.560 at 5% soil moisture content. RGR and NAR were comparatively affected by soil moisture content.

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The Effects of Waste Leachate on the Eco-Physiological Characteristics of Populus euramericana

  • Woo, Su-Young
    • The Korean Journal of Ecology
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    • v.22 no.6
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    • pp.343-348
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    • 1999
  • Populus euramericana has been identified as a possible species for use for phytoremediation of landfills. To identify the effects of waste leachate on the growth and physiological characteristics of Populus euramericana. four different treatments were applied to Populus euramericana seedlings: leachate solution (100% leachate). 25% dilution (75% leachate: 25% water. v/v), 50% dilution (50% leachate: 50% water. v/v) and control (100% tab water) were applied to Populus euramericana. Treatment with waste leachate significantly stimulated Populus euramericana height. diameter at root collar and biomass production relative to the water control. Chlorophyll contents. photosynthesis and transpiration of leachate irrigated-trees were significantly higher than those of water control. These results suggested that poplar could be a suitable species for phytoremediation in landfills because these species showed good growth performance and were capable of taking up waste leachate.

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Nucleation, Growth and Properties of $sp^3$ Carbon Films Prepared by Direct $C^-$ Ion Beam Deposition

  • Kim, Seong I.
    • The Korean Journal of Ceramics
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    • v.3 no.3
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    • pp.173-176
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    • 1997
  • Direct metal ion beam deposition is considered to be a whole new thin film deposition technique. Unlike other conventional thin film deposition processes, the individual deposition particles carry its own ion beam energies which are directly coupled for the formation of this films. Due to the nature of ion beams, the energies can be controlled precisely and eventually can be tuned for optimizing the process. SKION's negative C- ion beam source is used to investigate the initial nucleation mechanism and growth. Strong C- ion beam energy dependence has been observed. Complete phase control of sp3 and sp3, control of the C/SiC/Si interface layer, control of crystalline and amorphous mode growth, and optimization of the physical properties for corresponding applications can be achieved.

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Automatic Diameter Control System for Single Crystal Growth by Czochralski Method; Growth of Nd:YAG Single Crystal (Czochralski법에 의한 단결정 자동직경 제어시스템 개발;Nd:YAG 단결정 성장)

  • Bae, So-Ik;Lee, Sang-Ho;Kim, Han-Tae
    • Korean Journal of Crystallography
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    • v.7 no.1
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    • pp.1-7
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    • 1996
  • We developed an automatic diameter control system to control the diameter of single crystal for Czochralski growth. The system is composed of load cell, software program and data acquisition system connected to computer which controls RF power. This study describes the basic principle, characteristics and components of the system. The diameter of Nd:YAG crystal could be controlled within ±5% tolerance by this system.

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Implementation of Monitering system of Electromotion valve using 8255A (8255A를 이용한 전동밸브의 모니터링 시스템 구현)

  • Cho, Hyun-Seob;Ryu, In-Ho
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1694-1695
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    • 2007
  • DC-Motor is needed more and more sophisticated control to follow the highest precision of industrial automation and used in a number of control equipment or industrial fields. It is also useful to control single crystal(Al2O3) growth. It is possible to procure a quality crystal utilizing a DC-Motor, if you mix Hydrogen and Oxygen gas properly and keep proper temperature in accordance with time process. In this paper, we will study about electrical valve positioning system for the gas mixture to improve the quality of single crystal($Al_{2}O_{3}$) growth and we will design about realtime monitoring systems of the automatic gas contol DC- Motor for single crystal($Al_{2}O_{3}$) growth

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Effects on the Shoot Growth and Yield Related to Weed Control Methods at the Peach Orchard (복숭아 과원에서 잡초방제방법이 신초 생육 및 수량에 미치는 영향)

  • Lee, Sung-Hee;Lee, Ki-Yeol;Lee, Jae-Wung;Shin, Hyun-Man;Kang, Bo-Goo;Park, Yong-Seok;Lee, Jeong Deug
    • The Korean Journal of Pesticide Science
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    • v.19 no.2
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    • pp.134-140
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    • 2015
  • We studied to compare with the effect on the shoot growth and yield relavant to weed control methods in peach. As the results about 10 day intervals and 3 times investigation after each primary treatment, treatment plot of 2 times and 3 times with the herbicide, glufosinate ammonium, were 98.2~98.6% into $10^{th}$ day, 78.6~79.6% into $20^{th}$ day, 40.7~41.1% into $30^{th}$ day, fabric covering treatment showed 100%, 100% and 97.5% and treatment plot of machinery weeding were 92.1%, 56.4% and 36.4%, respectively. Also, we compared shoot growth for pre- and post-harvest. In the results, most of weed control methods showed better growth than control. Thus, the average number of standard fruits for treatment plot of 2 times with the herbicide and that of machinery weeding was different significantly in relation to control. Therefore, we think that the herbicide henceforth is well worth the application because treatment of 2 times or 3 times with the herbicide showed significant the control effect against all of 14 weed species surveyed in peach orchard and thus no inhibition for growth and number of standard fruits in peach trees.

Effects of Different Levels of Vitamin-Mineral Premixes on Growth Performance, Nutrient Digestibility, Carcass Characteristics and Meat Quality of Growing-Finishing Pigs

  • Tian, J.Z.;Lee, J.H.;Kim, J.D.;Han, Y.K.;Park, K.M.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.4
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    • pp.515-524
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    • 2001
  • Two experiments using growing and finishing pigs (Landrace$\times$Duroc$\times$Yorkshire) were conducted to determine the effects of different levels of vitamins and trace minerals (VTM) on growth performance, nutrient digestibility, carcass characteristics and meat quality of growing-finishing pigs, and to evaluate the suitability of vitamin-mineral levels commonly used in the swine industry in Korea. A total of 120 three crossbred (Landrace$\times$Duroc$\times$Yorkshire) growing (Experiment I: 20.90 0.44 kg average initial body weight) and finishing (Experiment II: 53.55 0.97 kg average initial body weight) were used in 6 and 9 weeks feeding trials, respectively. Pigs were allotted on the basis of sex and weight to 5 treatments with 6 replications per treatment with 4 pigs per pen in a completely randomized block design. Treatments were: 1) control, 2) fat soluble vitamin 200% vs. control, 3) water soluble vitamin 200% vs. control, 4) trace mineral 50% vs. control, 5) trace mineral 200% vs. control. In experiment I, during the overall experimental period (0 to 6 weeks, 21 to 54 kg body weight), ADG of the 200% trace mineral supplemented group was significantly higher than that of the 50% trace mineral supplemented group. There were no significant differences among other the treatments. Digestibility of crude protein was lowest in mineral 50% supplemented group (p<0.05). Calcium digestibility was significantly higher in the 200% fat soluble vitamin supplemented group than in the other treatments (p<0.05). In experiment II, during the overall experimental period (0 to 9 weeks, 54 to 106 kg body weight), growth performance was not significantly affected by dietary vitamin and trace mineral levels. However, increasing level of water soluble vitamins at the level of 200% compared to control had a tendency to improve the overall growth performance. Overall carcass characteristics except for carcass length did not differ among pigs fed the dietary treatments. Loin eye area, pH, drip loss and shear force of meat were not affected by dietary vitamin and trace mineral levels. There was a trend for less fat content (%) in pork when the level of vitamin and trace mineral was increased, but the difference was not significant. Flavor score was the lowest in control and highest in the 200% fat soluble vitamin supplemented group (p<0.05). Juiciness of muscle was lower in the 200% fat soluble vitamin supplemented group than other dietary treatments, except for trace mineral 50% supplemented group (p<0.05). Based on these results, it is suggested that "typical" commercial levels of vitamin and trace minerals used by feed companies in Korea are sufficient to meet requirement for the maximum growth of growing-finishing pigs. Our results suggests that a reduction in trace mineral levels in commercial diets could be considered to reduce feed cost and nutrient excretion with economic and environmental benefits.

Effect of Vesicular-Arbuscular Mycorrhizae on the Growth of Bell Pepper and Corn Seedlings (고추와 옥수수 실생의 생장에 미치는 균근의 효과)

  • Mun, Hyeong-Tae;Kim, Chong-Kyun;Choe, Du-Mun
    • The Korean Journal of Ecology
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    • v.13 no.1
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    • pp.1-8
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    • 1990
  • Effects of mycorrhizal infection on the growth of bell pepper (Capsicum annuum) and corn (Zea mays) seedlings have been studied by comparing plants grown in sterilized soil/sand mixtures to plants grown in sterilized soil/sand mixtures with topping the original non-sterile field soil. The original nonsterile field soil, which were taken from the bell pepper field, contained a high level of endmycorrhizal spores. After seven weeks, the shoot height of inoculated plants was increased by 110% in bell pepper, and 90% in corn compared with the control plants. The average above-ground biomass of inoculated plant was increased by 88% in bell pepper and 71% in corn compared with the control plants. The shoot-root ratios in bell pepper and corn were 2.7 and 1.8 for the control plants, and 4.3 and 2.7 for the treatment plants, respectively. Phosphorus level in inoculated plant was higher than that of the control plant. However, nitrogen contents were similar between the control and the treatment plants. The control plants didi not form vesicular-arbuscular mycorrhizae during the experimental period.

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FEEDBACK CONTROL FOR A TURBIDOSTAT MODEL WITH RATIO-DEPENDENT GROWTH RATE

  • Hu, Xiaoyu;Li, Zuxiong;Xiang, Xingguo
    • Journal of applied mathematics & informatics
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    • v.31 no.3_4
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    • pp.385-398
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    • 2013
  • In this paper, a turbidostat model with ratio-dependent growth rate and impulsive state feedback control is considered. We obtain sufficient conditions of the globally asymptotically stable of the system without impulsive state feedback control. We also obtain that the system with impulsive state feedback control has periodic solution of order one. Sufficient conditions for existence and stability of periodic solution of order one are given. In some cases, it is possible that the system exists periodic solution of order two. Our results show that the control measure is effective and reliable.

Generalized predictive control with exponential weight to control tempera-tures in ceramic drying furnace (세라믹 건조로 온도 제어를 위한 가중계수를 갖는 일반형 예측제어)

  • 임태규;성원준;금영탁;송창섭
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.13 no.6
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    • pp.284-289
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    • 2003
  • The electric furnace, inside which the desired temperature is kept by the generated heat, is known to be a difficult system to control and model exactly because system parameters and response delayed time are varied as the temperature and positions are changed. In this study, the GPCEW (generalized predictive control with exponential weight), which always guarantees the stability of the closed loop system and can be effectively applied to the internally unstable system, was introduced to the ceramic drying electric furnace and was verified by showing its temperature tracking performance experimentally.