• Title/Summary/Keyword: Biological systems

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Biological Activity of Extracts from Zea mays L. and Pinus densiflora L. (옥수수(Zea mays L.)와 소나무(Pinus densiflora L.) 추출물의 생물학적 활성)

  • ;Soul Chun;Nick E. Christians
    • Asian Journal of Turfgrass Science
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    • v.12 no.4
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    • pp.203-210
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    • 1998
  • Environmental concerns arising from synthetic herbicides in plant management systems have led to an interest in plant-derived compounds as natural herbicides. Inhibitory effects of compounds extracted with 50% methanol from corn (Zea mays L.) and pine (Pinus densiflora L.) were evaluated on large crabgrass (Digitaria sanguinalis (L.) Scop.), annual bluegrass Poa annua L.), radish (Raphanus sativus L.), and perennial ryegrass (Lolium perenne L.) The aqueous extracts inhibited seed germination and had postemergence activity on the four species. The stability of biological activity of corn grain, stover, and root extracts was not affected by heating to $135^{\circ}C$ or freezing/thawing treatments when applied at levels above 0.25kg m(sup)-2 based on dry weights of powders before extraction. Heating reduced the activity of pine litter and bark extracts at all levels except the highest application level but had little effect on pine needle extracts.

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DESIGN OF CONTROLLER FOR NONLINEAR SYSTEM USING DYNAMIC NEURAL METWORKS

  • Park, Seong-Wook;Seo, Bo-Hyeok
    • 제어로봇시스템학회:학술대회논문집
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    • 1995.10a
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    • pp.60-64
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    • 1995
  • The conventional neural network models are a parody of biological neural structures, and have very slow learning. In order to emulate some dynamic functions, such as learning and adaption, and to better reflect the dynamics of biological neurons, M.M. Gupta and D.H. Rao have developed a 'dynamic neural model'(DNU). Proposed neural unit model is to introduce some dynamics to the neuron transfer function, such that the neuron activity depends on internal states. Integrating an dynamic elementry processor within the neuron allows the neuron to act dynamic response Numerical examples are presented for a model system. Those case studies showed that the proposed DNU is so useful in practical sense.

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Silk Spinning Apparatuses in the Cribellate Spider Nurscia albofasciata (Araneae: Titanoecidae)

  • Park, Eun-Ah;Moon, Myung-Jin
    • Animal cells and systems
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    • v.13 no.2
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    • pp.153-160
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    • 2009
  • The fine structural characteristics of the silk spinning apparatus in the titanoecid spiders Nurscia albofasciata have been examined by the field emission scanning electron microscopy (FESEM). This titanoecid spiders have a pair of medially divided cribella just in front of the anterior spinnerets, and the surface of the cribellum is covered by hundred of tiny spigots which produce numerous cribellate silk fibrils. The cribellar silks are produced from the spigots of the sieve-like prate. and considered as a quite different sort of catching silk with dry-adhesive properties. The other types of the silk spigots were identified as follows: ampullate, pyriform and aciniform glands. Two pairs of major ampullate glands send secretory ductules to the anterior spinnerets, and another 1-2 pairs of minor ampullate glands supply the middle spinnerets. In addition, the pyriform glands send ductules to the anterior spinnerets, and two kinds of the aciniform spigots feed silk into the middle (A type) and the posterior spinnerets (both of A & B types), respectively.

Two New Spongia species (Dictyoceratida: Spongiidae) from Korea

  • Kim, Hye-Ri;Sim, Chung-Ja
    • Animal cells and systems
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    • v.13 no.2
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    • pp.141-145
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    • 2009
  • Two new species of the family Spongiidae, Spongia (Heterofibria) cora/lina n. sp. and Spongia (Heterofibria) purpurea n. sp. are described. They were collected from Gageodo Island, Jeollanam-do, Korea. Spongia (H.) coral/ina n. sp. is closest to S. (H.) cristata Cook & Bergquist (2001) from New Zealand in skeletal features, but the new species differs from S. (H.) cristata by the arrangement of fibres and growth form. Spongia (H.) purpurea n. sp. closley resembles S. (H.) cristata, but the new species differs from New Zealand specimens by the arragement and thickness of pseudo-tertiary fibres.

Comparison of Proportional, Integral, and P-I Control Systems in Biological Wastewater Treatment Plants (생물학적 하수처리시스템에 적용된 Proportional, Integral 및 P-I 조절 시스템에 대한 비교)

  • Kim, Sungpyo
    • Journal of Korean Society on Water Environment
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    • v.21 no.4
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    • pp.410-415
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    • 2005
  • The main purpose of this study is to evaluate the characteristics of three sets of traditional control methods (proportional, integral, and proportional - integral controls) through lab-scale biological reactor experiments. An increase in proportional gain ($K_c$) resulted in reduced dissolved oxygen (DO) offset under proportional control. An increase in integral time ($T_i$) resulted in a slower response in DO concentration with less oscillation, but took longer to get to the set point. P-I control showed more stable and efficient control of DO and airflow rates compared to either proportional control or integral control. Developed P-I control system was successfully applied to lab-scale Sequencing Batch Reactor (SBR) for treating industrial wastewater with high organic strength.

복합오염물질 처리를 위한 Hybrid PRB System

  • 김상태;강완협;문희선;민지은;조종수;박주양;김재영;박재우
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.129-132
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    • 2004
  • A hybrid permeable reactive barriers(hybrid PRBs) composed of Fe(II) PRB, biological PRB and sorptive PRB was investigated to treat groundwater with multiple contaminations. We performed batch, column and pilot tests to determine removal rates and design parameters of each PRB media, and operated two hybrid PRB systems with pilot-scale barriers in series. The pilot test of the hybrid PRB system with the combination of Fe(II), biological media and black shale showed multiple contaminations could be removed in ground water. Nitrate could be treated below 20 mg/L and Cr(VI) was treated down to 0.05 mg/L. TCE was degraded below 0.001 mg/L in system. The hybrid PRB system with a proper combination of PRBs could remediate ground water with multiple contaminations.

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A Study on the millimeter-wave stimulation on acupuncture points and it′s biological effects (경혈의 밀리파 자극과 그 영향에 관한 연구)

  • Byeon, Mi-Kyeong;Han, Sang-Whi;Kim, Jung-Kuk;Huh, Woong;Park, Young-Bae
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.129-132
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    • 2002
  • In this paper, we describe a millimeter-wave radiation system developed for stimulating acupuncture points, and an analyzing system developed for monitoring the change of physiological signals after the stimulation such as ECG, skin temperature, skin potential and skin resistance. The systems are to be used to investigate the treatment efficacy and biological effects of the millimeter-wave, and eventually, can be used to study the acupuncture meridian system theory in the traditional Korean medicine.

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Identification and Control of Nonlinear System Using Dynamic Neural Model with State Parameter Representation (상태변수 표현을 가진 동적 신경망을 이용한 비선형 시스템의 식별과 제어)

  • Park, Seong-Wook;Seo, Bo-Hyeok
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.157-160
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    • 1995
  • Neural networks potentially offer a general framework for modeling and control of nonlinear systems. The conventional neural network models are a parody of biological neural structures, and have very slow learning. In order to emulate some, dynamic functions, such as learning and adaption, and to better reflect the dynamics of biological neurons, M.M.Gupta and D.H.Rao have developed a 'dynamic neural model'(DNU). Proposed neural unit model is to introduce some dynamics to the neuron transfer function, such that the neuron activity depends on internal states. Numerical examples are presented for a model system. Those case studies showed that the proposed DNU is so useful in practical sense.

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Studying immune system using imaging and microfabrication (생체영상과 미세가공을 이용한 면역 시스템 연구)

  • Doh, Jun-Sang
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1446-1449
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    • 2008
  • Immune system is composed of multiple cells with distinct functions, and immune responses are orchestrated by complex and dynamic cell-cell interactions. Therefore, each cell behavior and function should be understood under right spatio-temporal context. Studying such complexity and dynamics has been challenging with conventional biological tools. Recent development of new technologies such as state of art imaging instruments and microfabrication techniques compatible with biological systems have provided many exciting opportunities to dissect complex and dynamic immune cell interactions; new microscopy techniques enable us to observe stunning dynamics of immune system in real time. Microfabrication permits us to manipulate microenvironments governing molecular/cellular dynamics of immune cells to study detailed mechanisms of phenomena observed by microscopy. Also, microfabrication can be used to engineer microenvironments optimal for specific imaging techniques. In this presentation, I am going to present an example of how these two techniques can be combined to tackle challenging problems in immunology. Obviously, this strategy can readily be applied to many different fields of biology other than immunology.

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DNA Coding Method for Time Series Prediction (시계열 예측을 위한 DNA 코딩 방법)

  • 이기열;선상준;이동욱;심귀보
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.280-280
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    • 2000
  • In this paper, we propose a method of constructing equation using bio-inspired emergent and evolutionary concepts. This method is algorithm that is based on the characteristics of the biological DNA and growth of plants. Here is. we propose a constructing method to make a DNA coding method for production rule of L-system. L-system is based on so-called the parallel rewriting mechanism. The DNA coding method has no limitation in expressing the production rule of L-system. Evolutionary algorithms motivated by Darwinian natural selection are population based searching methods and the high performance of which is highly dependent on the representation of solution space. In order to verify the effectiveness of our scheme, we apply it to one step ahead prediction of Mackey-Glass time series.

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