• Title/Summary/Keyword: Complex plants

검색결과 641건 처리시간 0.029초

Genomics and Biotechnology of Plant Adaptation to the Environment

  • Mullet, John E.
    • Journal of Applied Biological Chemistry
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    • 제43권4호
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    • pp.192-196
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    • 2000
  • The molecular basis of plant adaptation to the environment is one of the most complex areas of plant science and an understanding of this subject is critical to our ability to feed an increasing word population. Research on plant adaptation to the environment often involves two complementary approaches; top-down studies of well-adapted plants with the goal of identifying and describing the biochemical basis of adaptation and bottom-up targeted analysis of specific biochemical mechanisms with the goal of understanding how these mechanisms contribute to overall plant performance. This brief review will provide examples of both of these approaches by describing the study of sorghum's adaptation to dry environments and the role of a blue light responsive chloroplast promoter that helps protect plants against damage by high irradiance.

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HUMAN-MACHINE INTERACTION IN NUCLEAR POWER PLANTS

  • YOSHIKAWA HIDEKAZU
    • Nuclear Engineering and Technology
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    • 제37권2호
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    • pp.151-158
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    • 2005
  • Advanced nuclear power plants are generally large complex systems automated by computers. Whenever a rare plant emergency occurs the plant operators must cope with the emergency under severe mental stress without committing any fatal errors. Furthermore, The operators must train to improve and maintain their ability to cope with every conceivable situation, though it is almost impossible to be fully prepared for an infinite variety of situations. In view of the limited capability of operators in emergency situations, there has been a new approach to preventing the human error caused by improper human-machine interaction. The new approach has been triggered by the introduction of advanced information systems that help operators recognize and counteract plant emergencies. In this paper, the adverse effect of automation in human-machine systems is explained. The discussion then focuses on how to configure a joint human-machine system for ideal human-machine interaction. Finally, there is a new proposal on how to organize technologies that recognize the different states of such a joint human-machine system.

Method for Inference of Operators' Thoughts from Eye Movement Data in Nuclear Power Plants

  • Ha, Jun Su;Byon, Young-Ji;Baek, Joonsang;Seong, Poong Hyun
    • Nuclear Engineering and Technology
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    • 제48권1호
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    • pp.129-143
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    • 2016
  • Sometimes, we need or try to figure out somebody's thoughts from his or her behaviors such as eye movement, facial expression, gestures, and motions. In safety-critical and complex systems such as nuclear power plants, the inference of operators' thoughts (understanding or diagnosis of a current situation) might provide a lot of opportunities for useful applications, such as development of an improved operator training program, a new type of operator support system, and human performance measures for human factor validation. In this experimental study, a novel method for inference of an operator's thoughts from his or her eye movement data is proposed and evaluated with a nuclear power plant simulator. In the experiments, about 80% of operators' thoughts can be inferred correctly using the proposed method.

수직축 Wind-Turbine을 이용한 풍력발전 모델의 연구 (A Study of Wind Energy Power Plants Models using V.A.W.T)

  • 명관범;차득근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 B
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    • pp.1522-1524
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    • 2004
  • The wind turbine captures the wind's kinetic energy in a rotor consisting of two or more blades mechanically coupled to an electrical generator. In this paper is proposed models for wind energy power plants using V.A.W.T. and complex concepts using shapes of a half cylinder for blades. A familiar configuration for a drag-type wind machine is shown this paper. In this simple machine, kinetic energy in the wind is converted into mechanical energy in a vertical rotating shaft.

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VHDL을 이용한 디지털 계전 알고리즘 구현에 관한 연구 (A Study on the Implementation of Digital Protective Relay Algorithm using VHDL)

  • 권오상;허정용;김철환
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.251-253
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    • 2004
  • Nowadays, power customer has increased and new power plants have been constructed for market demands. However, increasement of power plants make power system more complex and unstable. For this reason, the stability problem is one of the most important issues in power systems. In this paper, a study on implementation of out-of-step detection algorithm is performed. The structure of digital relay is analyzed for development of out-of-step detection algorithm. DFT block which is used to extract basic frequency of voltage is analyzed to design VHDL.

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Phytochemical Compounds from the Ethanolic Extract of Gymnema sylvestre, Senna auriculata and Cissus quadrangularis through GC-MS Analysis

  • Sindhuja G;Mary Agnes A
    • Mass Spectrometry Letters
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    • 제14권2호
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    • pp.25-35
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    • 2023
  • Plants are a traditional source of many chemicals used as biochemical, flavors, food, color, and pharmaceuticals in various countries, especially India. Most herbal medicines and their derivatives are often made from crude extracts containing a complex mixture of various phytochemical chemical components (secondary metabolites of the plants). This study aimed to identify bioactive compounds from the different parts of the plant from the ethanolic extract of Gymnema sylvestre, Senna auriculata, and Cissus quadrangularis (leaves, flower, stem) by gas chromatography-mass spectroscopy (GC-MS). The gas chromatography - mass spectrometry analysis revealed the presence of various compounds like 3,4-dimethylcyclohexanol, hexanoic acid, D-mannose, and N-decanoic acid. Hence, the Gymnema sylvestre, Senna auriculata, and Cissus quadrangularis may have chemopreventive, anti-cancer, anti-microbial activity, antioxidant, anti-diabetic activity, anti-inflammatory, and antifungal due to the presence of secondary metabolites in the ethanolic extract. These phytochemicals are supported for traditional use in a variety of diseases.

공단지역에 우점하고 있는 덩굴식물류의 식생변화 (Vegetation of Liana Dominating in the Vicinity of Onsan Industrial Complex)

  • 박은희;김종갑;이정환;조현서;민재기
    • The Korean Journal of Ecology
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    • 제27권6호
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    • pp.335-345
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    • 2004
  • 우리나라 공업단지 중 화학비료를 생산하고 있는 온산공단주변의 해송림이 쇠퇴된 이후 그곳에 덩굴식물류의 우점현상을 평가하기 위하여 식생조사를 실시하였다. 하층식생에 덩굴식물류의 중요치는 청미래덩굴(Smilax china)이 13.2로 가장 높았으며, 인동(Lonicera japonica)이 11.7, 계요등(Paederia scandens) 11.5, 댕댕이덩굴(Cocclus trilobus)이 7.7의 순으로 높아 대기오염으로 인한 생태계 훼손지역의 1차 식생으로 나타남을 알 수 있었다. 각 조사지별 목본류의 종수와 종다양도, 최대종다양도, 균재도, 우점도를 층위별로 나타낸 결과상층, 중층 식생에서는 종수, 종다양도, 최대종다양도, 균재도, 우점도가 산림지역이 공단지 역보다 높게 나타나 공단 주변 식생의 단순함을 보였으며, 하층 식생에서는 공단지역이 산림지역보다 높게 나타났는데 이는 덩굴식물이 차지하고 있는 비율이 높은 것이 원인인 것 같다. 초본류 조사에서는 총 59종이 출현하였으며, 고사리, 기름새, 닭의장풀, 미국자리공, 멍석딸기, 억새, 실새풀 등에서 중요치가 높아 대기오염지역의 우점종으로 나타났으며, 종수, 종다양도, 최대종다양도, 균재도, 우점도에서는 지역간의 구분이 뚜렷하게 나타나지는 않았지만 공단지역이 산림지역보다는 덩굴식물의 분포가 높게 나타났다. 이는 인접한 경기화학의 영향으로 상층식생의 쇠퇴에 따른 광조건에 의하여 열대성 식물인 덩굴식물이 우점종으로 나타나 생태계의 교란으로 인한 사막화 현상에 응용할 수 있을 것으로 생각된다.

Antioxidative Activity and Irritation Test of a Complex Herbal Bath Extracted from Korean Traditional Plants

  • Chang Zhiqiang;Kim Young-Hoan;Song Jae-Chan;Kim Nam-Woo;Lee In-Seon;Lee Sam-Pin;Kim Jong-Choon;Park Seung-Chun
    • Toxicological Research
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    • 제21권1호
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    • pp.45-49
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    • 2005
  • The purpose of this study is to evaluate the free radical scavenging ability and xanthine oxidase inhibitory activity of a complex herbal bath consisted of Artemisiae argyi folium, Angelicae sinensis radix, Ligustici wallichii radix and Angelicae tuhuo radix, and its potential irritation response were also tested for safety use in the rabbits. For antioxidative activity, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of the complex herbal bath were examined at five different concentrations (0, 250, 500, 1000 and 2000 ㎍/ml). The concentration of the complex herbal bath required for scavenging DPPH free radical by 50% was 897.2 ㎍/ml. In the inhibition of xanthine oxidase (XO) activity, the concentration of the complex herbal bath required for 50% of inhibition was 221.4 ㎍/ml. In the skin irritation study in rabbit, all animals survived for the duration of the study and the examined skin exhibited no edema, erythema, and eschar formation. In the ocular irritation study in rabbit, after application of the sample to eyes, all of the eyes were normal. In summary, the complex herbal bath has potent antioxidant effects against the DPPH radical and XO and was considered to be a non-irritation bath for safety use.

STAD학습에서 복합보상이 학업성취도와 학습태도에 미치는 효과 (The Effect of the Complex Reward in STAD Learning on Academic Achievement and Learning Attitudes)

  • 김선수;최도성
    • 한국초등과학교육학회지:초등과학교육
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    • 제21권1호
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    • pp.101-109
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    • 2002
  • A cooperative teaming has been taken to consolidate the autonomous motivation of students and to develop a desirable attitude in a mutual cooperative atmosphere. Some studies on the reward effect showed that the reward after the evaluation, in the processes of cooperative learning, worked on students' learning motive directly, and the group reward was effective in learning attitude and the individual reward in academic achievement, respectively. Assuming that the group reward and the individual reward are organized and applied as a complex reward, the effects of rewards will appear, this study examined the effect of the complex reward on academic achievement and teaming attitude. For this study. 2 classes were randomly selected out of a elementary school in Gwangju and the teaming unit was based on chapter 4「The structure and function of plants」 in the 5-1 elementary Science textbook. This research has been done for 4 weeks after the students learned STAD for 8 weeks previously. The learning attitude was examined in pre and post tests, and the academic achievement was inspected twice at 2-week intervals after the pre test. The results were analysized by the SAS program In the case of academic achievement, both groups showed a significant improvement(p<.05). The experimental group showed no significant improvement in the first test, compared with the control group(p>.05), but after 4 weeks, it showed a significant improvement in the second test, compared with the control group(p<.05). From this result, it is identified that the reward should be done for a long time and the individual reward of the complex reward is successful in improving academic achievement. However, in the case of learning attitude, there was no meaningful difference in both groups(p>.05). But the control group showed a significant improvement, compared with the experimental group(p<.05). According to this result, it is indicated that the group reward only is more effective in improving learning attitude and complex reward can decrease the individual competition in experimental group.

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한국형발사체 발사대 고압가스 공급시스템 소개 (Introduction to the Compressed Gas Supply System of KSLV-II Launch Complex)

  • 오화영;안재철;강선일;박정근
    • 한국추진공학회지
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    • 제21권1호
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    • pp.91-97
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    • 2017
  • 한국형발사체 발사대시스템은 지상기계설비, 추진제공급설비, 발사관제설비 그리고 기반시설로 구성된다. 추진제공급설비의 구성품인 고압가스 공급시스템은 우주발사체 발사 운용에 필요한 고압가스를 저장하고 각 사용처에 공급하는 역할을 수행한다. 고압가스 공급시스템은 고압가스 저장부, 조정패널, 제어서브시스템 등으로 구성되며, 조정패널 중 자동패널은 제어기와 연동되어 원격으로 구동이 가능하도록 구축된다. 본 논문에서는 한국형발사체와 발사대시스템 지상설비의 특성을 고려하여 설계된 고압 가스 공급시스템에 대해 소개하고자 한다.