• Title/Summary/Keyword: Human disturbance

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Design of fuzzy algorithms for DC motor speed control (DC 모터 속도제어를 위한 퍼지 알고리즘 설계)

  • 최종수;김성중;최한수
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.676-680
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    • 1991
  • This paper proposes fuzzy control algorithms for a DC moter speed control. The proposed algorithms are constructed by the fuzzy controller and the fuzzy compensator. The fuzzy compensator used to overcome rapidly the effects caused by the disturbance and is mounted outside of the closed loop of the fuzzy controller. The fuzzy control rules are established from human operator experience and basic engineering knowledge about the process dynamics. Simulation results show that the proposed algorithms compensate for parameter variation and disturbance.

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Effects of Natural Independent Visual Background for Reducing Simulator Sickness (자연형 IVB(Independent Visual Background)의 Simulator Sickness 감소효과)

  • 김도회;임정위
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.25 no.3
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    • pp.28-33
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    • 2002
  • Several studies indicated that an independent visual background (IVB) reduced simulator sickness (SS) and balance disturbance associated with exposure to virtual environments (VEs) and motion simulators. A recent study showed that an IVB comprised of an earth-fixed grid was less effective in a complex driving simulator than in a simple VE. Subjects' post-experiment reports indicated that the VE motion "induced" motion of the earth-fixed grid m. This led to the suggestion that an IVB comprised of clouds would be less subject to induced motion and therefore would alleviate nausea more effectively than a grid IVB. Clouds are "natural" and are usually perceived as relatively stable, whereas a grid has no inherent stability. 12 subjects were exposed to complex motion through a simulated environment in a driving simulator under 3 IVB conditions: grid, less clouds, many clouds. They reported less nausea when the many-cloud IVB was used relative to the grid IVB condition. grid IVB condition.

Regulation of Fruit and Seed Production in Selfing Annual, Vigna unguiculata (일년생 자가수분 식물인 동부의 열매 및 종자 생산의 조절에 관한 연구)

  • 이수진;장남기
    • Asian Journal of Turfgrass Science
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    • v.9 no.2
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    • pp.137-157
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    • 1995
  • Some indices of species of the Arundinella hirta communities in Cheolwon area were studied and the following results were obtained. The vegetational date was analyzed from six grass stands selected with the distance away from the DMZ in Cheolwon area. Species diversity was higher in the stand away from the DMZ than in that neat to it. All six stands are not considered to be free of disturbance. Species composition of the stands might be related to the degree of disturbance. It can be said that the destruction of the vegetation by periodical fire or cutting simplifies the species composition. In the rear district the human inter ference is supposed to be more frequent. But it is supposed to be slight in near the DMZ and that the degree of disturbance is not so destructive. This could be the explanation of high diversity in these stands.

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Effects of weather change, human disturbance and interspecific competition on life-history and migration of wintering Red-crowned cranes (기후변화와 인간의 방해 및 종간경쟁이 두루미 월동생태와 이동에 미치는 영향)

  • Hong, Mi-Jin;Lee, Who-Seung;Yoo, Jeong-Chil
    • Korean Journal of Environment and Ecology
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    • v.29 no.5
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    • pp.681-692
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    • 2015
  • It is well documented that physiological and nutritional condition of wintering birds is strongly related to migration success to breeding sites, and also breeding success. However, how abiotic factors during winter affect the migration and breeding successes still remains unclear. Thus, this study developed a dynamic-state-dependent model for wintering life-history to identify the potential impact on the life-history, success to breeding site and breeding success of wintering birds, which are related to temperature fluctuation, interspecific competition and human disturbance at the wintering sites. To find the best-fit-model, we referred to the existing research data on wintering ecology of Red-crowned cranes (Grus japonensis) in Cheolwon, Korea, which is well documented as a long-term wintering study. Our model predicted that the higher temperature fluctuation and a higher rate of human disturbance are negatively related to migration success to breeding sites and their fitness, ultimately breeding success via changing of proportion in resource allocation (for e. g., lower energy compensation or higher level of stress accumulation). Particularly, the rate of body mass compensation after arrival at wintering sites may be accelerated when there are less temperature fluctuations and a lower rate of human disturbance. In addition, the rate of interspecific competition sharing the wintering foraging sites is negatively related to the rate of body mass compensation. Consequently, we discussed the conservation strategies of wintering birds based on the outcomes of the model.

Visual Disturbance following Autologous Fat Injection into Periorbital Area (안와부 자가지방이식술 후 시력 저하에 대한 증례보고)

  • Jeon, Young Woo;Kim, Sung Soo;Ha, Sang Wook;Lee, Young Dae;Seul, Chul Hwan;Tark, Kwan Chul;Cho, Eul Jae;Yoo, Won Min
    • Archives of Plastic Surgery
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    • v.34 no.5
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    • pp.663-666
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    • 2007
  • Purpose: Autologous fat injection into the facial area is a frequently used technique in aesthetic plastic surgery for augmentation of the soft tissue. Fat injection is a very safe procedure because of the advantage of being autologous tissue. Minimal foreign body reaction or infections are noted after fat injection. However, there may be some complications including those as severe as blindness. There have been some case reports on visual disturbances after autologous fat injection reported in the literature. Methods: A 21-year-old female patient underwent autologous fat injection into left eyebrow area to correct depression of soft tissue. Immediately after injection of autologous fat, she complained sudden visual loss on the left eye. She had come to our emergency room and ophthalmologic evaluation showed that the patient could only recognize hand motion. There was no abnormality of the optic nerve on magnetic resonance imaging. Suspecting an ischemic optic neuritis from fat embolism of the central retinal artery, the patient was treated conservatively with occular massage, antiglaucomatic agent, anti-inflammatory drugs and antibiotics. Visual field examination showed visual defect of half the lower hemisphere. Results: While maintaining antiglaucomatic agents and non steroidal anti inflammatory drugs, fundoscopic examination showed no abnormalities on the second day of admission. Visual field examination showed an improvement on the fourth day along with decreased eyeball pain. Significant improvement of vision was noted and the patient was discharged on the fifth day of admission. The patient was followed-up 2 days afterwards with improved vision and visual field defect. Conclusion: We describe an unusual case of sudden unilateral visual disturbance following autologous fat injection into periorbital area.

The change of core habitats of the cranes due to release of the civilian control zone; CCZ and construction disturbance (서식지 교란 및 민간인통제지역 해제에 의한 두루미와 재두루미의 핵심서식지 변화)

  • Yoo, Seunghwa;Jung, Hwayoung;Kim, Kyoungsoon;Yu, Dong Su;Kim, Namshin;Kim, Hwajung;Hur, Weehaeng;Kim, Jinhan;Lee, Kisup
    • Journal of Environmental Impact Assessment
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    • v.24 no.4
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    • pp.301-316
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    • 2015
  • The endangered species, The Red-crowned Crane and the White-naped Crane are vulnerable species to the disturbance for human beings. We examined the importance of CCZ for the cranes by comparing the crane's density in some CCZ-released areas, which are cranes' wintering site in Cheorwon. We also assessed influence of disturbance such as construction and greenhouses on core habitats of cranes. Our study results suggested that the construction and reclamation in the CCZ shrunk core habitat area while increasing core area of far from the construction and reclamation area. The CCZ has been set since March, 2011 and the number of greenhouse has rapidly increased after 2012. As the number and size of greenhouse in the area where designation of CCZ was cancelled increased, foraging area of cranes diminished. Although the area where designation of CCZ was cancelled seemed to have more human disturbance than CCZ, the foraging density of cranes did not decline and even that of white-naped cranes increased. This could be the influence of artificial food supply at their roosting site. In conclusion, if the area of CCZ decline continuously in the future, density of cranes would decrease.

The Effects of Green Tea Supplementation on Behavioral Changes, Striatal Dopamine Level, and Hepatic Antioxidant Parameters of Parkinson's Disease Model Rats

  • Kang, Min-Jeong;Lee, Sang-Sun
    • Nutritional Sciences
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    • v.9 no.2
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    • pp.61-67
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    • 2006
  • Green tea has attracted attention with respect to its potential for preventing and treating neurodegenerative disease. The neurotoxin, 6-hydroxydopamine (6-OHDA), was used to produce experimental Parkinson's disease (PD) model. The purpose of this study was to investigate the effects of green tea diet on behavioral changes, striatal dopamine content, and hepatic antioxidant parameters of PD model rats. In this study, we used male Sprague-Dawley rats weighing $200\sim220g$ and injected 6-OHDA into the right substantia nigra and medial forebrain bundle of the brain. The supply of green tea diet was started at 2 weeks before 6-OHDA lesion and continually supplied during 0, 2, and 4 weeks after 6-OHDA lesion (GT-0, GT-2, GT-4). Behavioral disturbance was measured by the stepping and d-amphetamine drug-induced rotation tests. Then, we assayed the striatal dopamine content and the hepatic malondialdehyde (MDA), hydrogen peroxide $(H_2O_2)$, and superoxide dismutase (SOD) activity. The percentage of lesioned forepaw to non-lesioned forepaw step scores was the highest in GT-4 group among all groups at both 3 and 4 weeks after 6-OHDA lesion. At 4 weeks after 6-OHDA lesion, the rotation score was the lowest in GT-2 group (p<0.05). However, increasing rate of the rotation score from 2 to 4 weeks after 6-OHDA lesion was the lowest in GT-4 group. The striatal dopamine content was not significantly different among four groups by green tea diet. The hepatic MDA level was the lowest in GT-4 group among four groups. The hepatic SOD activity was increased with the prolongation of green tea diet period These results suggest that green tea diet affects behavioral changes in rats of PD model. It seems that continuous green tea supplementation has an influence on the reduction of behavioral disturbance and the hepatic MDA level. Accordingly, continuous green tea supplementation was recommended for the prevention and treatment of PD. However, further studies are needed to investigate the mechanisms and efficacy of green tea in PD.

Vegetation Structure arid Management Planning of the Sansung Nature Park, Cheonju (전주시 산성자연공원의 식생구조 및 관리대책)

  • 최만봉;이규완;오구균
    • Journal of the Korean Institute of Landscape Architecture
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    • v.18 no.1
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    • pp.41-51
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    • 1990
  • This study was executed to investigate the vegetation structure and to propose the vegetation management proposals of the Sansung Nature Park at Cheonju City and the results were as fellows. 1. A damage of vegetation and soil surface around the Namgosa was taken place up to 100m by picnic 2. Pinus rigida forest covered 36.1% of the total area(152.6ha) and total afforested vegetation covered 43.5%, respectively. P. denstflora comm. covered 28.4% arid Carpinus laxiflora Comm. as a climax vegetation in temerate zone covered 0.3%, respectively. 3. 6, 7 and 8 of the degree of human disturbance of vegetation covered 45.3%, 26.6% and 21.4%, respectively and resulted in low quality of naturalness. 4. Physical and chemical properties of soil were pour at high elevation and were poor severely in and around the Namgosa due to human disturbance. 5. Plant community were under rapid succession and had unvalanced structure and heterogeneous composition of species. Rapid vegetational succession from Pinus densiflora and Pf. rigida to Carpinus laxifora, Quercus spp. and Robinina pseudo-acacia were taken place.6. The speeies of Raunkiaer's frequency class I as of high frequency class were Pinus dunsiflora, Carpinus alxiflora, Quercus mmongolica, Sorbus alnifolia, Prunrs sargintii, Rhododendron yedoense, Stephanandra incisa and Lespedeza maxinowiczii. 7. Vegetational management proposals were made for three vegetation zones ; Historic landscape restoration and preservation zone, Afforested vegetation zone, Native vegetation conservation zone and recommanded native species for landcape planting.

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