• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.307-311
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• 2003

2-mass system is generally used as controller of the variable-speed to transfer electromotion power to mechanical load such as industrial robot, driving parts of electric vehicle, rolling machine system of steel plant and driving parts of elevator. In this case, PI controller is often used as a velocity controller because of simplicity of system. But PI control algorithm is not enough for obtaining the control characteristics required for this system. To solve this problem, 2-mass system based on the PID controller derives the optimum PID parameters by pole assignment and estimation of the ITAE performance index. In this case, the system have tenacious properties about disturbance, but it causes extreme overshoot and vibration because of rapidly output of controller in early transient response about desired value. And if speed control system is applied by 2-DOF parameter ${\alpha}$, a temporary value, we must induce most suitable parameter by complicate pole assignment and estimation of the ITAE performance index whenever ${\alpha}$ changes. In this paper, to solve this problem we suggest control algorithm to followed exactly value of ${\alpha}$ as 2-DOF parameter by using fuzzy algorithm . So, intelligence algorithm modeled by human knowledge, experience, teachability and judgment follow exact ${\alpha}$ value and it can compose the efficient 2-DOF PID controller to improve following performance, overshoot decrease.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.1
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• pp.61-74
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• 2002

The purpose of this study is to propose vegetation management devices through analyzing the actual vegetation, flora, plant community structure and soil chemical concentrations in Weolmi urban nature park, Incheon. The actual vegetation of Weolmi Park in various areas is composed of urbanization area(2 types, 25.9%), landscape planting area(4 types, 16.1%), grass and marsh area(5 types, 7.6%) and mountain forest areal(14 types, 50.4%). The flora is composed of 295 taxa with 80 families, 253 species, 35 varieties and 7 formas, and among them there are 16 naturalized plant families, 39 species, 3 varieties. In reflection of size, the number of the species seems high but most of the them are under influence of human disturbance. Nine survey plots of plant community structure are classified into two groups. One is the semi-natural plant community(Prunus sargentii-Acer palmatum, Quercus accutissma-Prunus sargentii, Quercus serrata-Quercus accutissma-Prunus sargentii, Prunus sargentii, and Zelkova serrata-Prunus sargentii) that migrated finn the planting forest to the natural forest and the other is planting forest(Pinus koraienssis-Pinus thunbergii-Abies holophylla-Chamaectparis obtusa, Prunus sargentii, Pinus thunbergii-Alnus firma, Zelkova serrata). The average pH is 4.65 which means the soil acidity is quite high. The concentration of K, Ca, Mg and base saturation is very low. It seems that the environmental pollutants from Incheon Port and industrial plants near by survey site and long-distance transport of air pollutants from China made the soil condition worse. On the basis of the results above, six vegetation management devices are suggested: 1) removing the hazard plants(Pueraia thunbergiana and Humulus japonica), 2) natural landscape management of the middle and long term, 3) increasing species diversity, 4) Robinia pseudoacacia management, 5) keeping the naturalized plants from being distributed any further inside the mountain forest, 6) improving soil acidification.

• The Korean Journal of Ecology
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• v.24 no.6
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• pp.385-394
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• 2001

An attempt to clarify the landscape structure of urban areas was carried out in the greenbelt around Seoul, Korea's metropolis. By means of aerial photographs and a field survey, a vegetation map including land-use pattern was made. Landscape structure was described by analyzing this vegetation map and the results of phytosociological survey. Landscape element types identified were (1) secondary forest, (2) plantation, (3) cultivated field, (4) urbanized area, (5) graveyard, and (6) bare rock. Vegetation units, resulting from the phytosociological analysis, included Quercus mongolica, Q. variabilis, Q. acutissima, Pinus densiflora, Q. aliena, and Alnus japonica communities. Plantations were composed of Robinia pseudoacacia, Populus tomentiglandulosa, P. rigida, Larix leptolepis, P. koraiensis, and Castanea crenata stands. Patches near to human settlements in the lower zones of the mountains were fragmented and small but they became larger towards the higher mountain zones. On the other hand, the number of patches was fewer and their size was larger in Mt. Cheonggye more distant from the principal residential area, larger in size, and higher in elevation compared with the other 2 mountains, Mt. Daemo and Mt. Acha. Floristic composition of Mongolian oak(Q. mongolica) stand distributing in the upper part of each mountain, in which artificial interference is rare, showed a difference among those study areas different in parent rock and disturbance regime. But that of black locust(R. pseudoacacia) stand located in lowland of mountainous area, in which artificial interference is frequent was similar to each other. As the results of analyses on the frequency distribution of diameter classes of major species, dominant landscape elements, Mongolian oak forest showed different responses depending on artificial interference as continuous maintenance and retrogressive succession in the sites far from and near to the residential areas, respectively. On the other hand, black locust stands showed a probability to be restore to the native oak forest through progressive succession.

• Journal of Environmental Science International
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• v.12 no.12
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• pp.1207-1213
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• 2003

Osancheon creek is located in the southwest of the middle area in Korea. Weed community around the Osancheon creek, where various disturbances exert a bad influence directly on its community by human work or nature, was surveyed phytosocialogically. Our surveys have been accomplished from June, 2003 to September, 2003. Weed communities formed around the Osancheon creek were divided into several patterns and analysed. They have been divided into 8 communities. Community A: Humulus japonica community, B: Phragmites communiscommunity, C: Persicaria thunbergii community, D: Zi=ania latifolia community, E: Miscanthus saccharilflorus community, F: Echinochica crusgalli community, G: Typha orientalis community, H: Sataria viridis community. The flora surveyed in these communities was constituted of 19 families, 36 genera, 4 varieties, and 40 species. Wild plants such as Artemisia princeps var. orientalis Erigeron annuus, Bidens frondosa, Aeschynomene indica and Oenothera odorata were mostly light loving plants and higher resistant plants against the disturbance. Our result from the ranking all surveyed areas by the Bray-Curtis ordination method was very similar to the results from phytosocialogical table work.

• Journal of Environmental Impact Assessment
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• v.15 no.5
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• pp.339-355
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• 2006

In this paper, we reviewed the assessment criteria and conservation value used to evaluate vegetation. The Degree of Green Naturality (DGN) and the Grade of Vegetation Conservation (GVC) are both sets of criteria that estimate the degree of human disturbance or natural value of vegetation. The criteria are extensively used in decision-making about the natural environment conservation and environment impact assessment. Sometimes, social issues can rise because the criteria are not clear. This study aims to evaluate the criteria based on the many aspects of the related literatures and suggest reasonable revised criteria. In addition, criteria for representing the relative value of valuable vegetation conservation are suggested. The DGN and GVC are essentially same; both have 11 degrees and 5 grades. While the DGN is subdivided into levels of anthropogenic disturbances, the GVC indicates the priority for conserving valuable vegetation. Therefore, the DGN is very useful for assessing land development projects, etc., while the GVC is needed to delineate the Ecological Assessment Map(EAM). In conclusion, it is desirable that both criteria should be used together appropriately.

• International Journal of Automotive Technology
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• v.4 no.4
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• pp.181-191
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• 2003

Since the nonlinearity and uncertainties which inherently exist in vehicle system need to be considered in active suspension control law design, this paper proposes a new control strategy for active vehicle suspension systems by using a combined control scheme, i.e., respectively using a genetic algorithm (GA) based self-tuning PID controller and a fuzzy logic controller in two loops. In the control scheme, the PID controller is used to minimize vehicle body vertical acceleration, the fuzzy logic controller is to minimize pitch acceleration and meanwhile to attenuate vehicle body vertical acceleration further by tuning weighting factors. In order to improve the adaptability to the changes of plant parameters, based on the defined objectives, a genetic algorithm is introduced to tune the parameters of PID controller, the scaling factors, the gain values and the membership functions of fuzzy logic controller on-line. Taking a four degree-of-freedom nonlinear vehicle model as example, the proposed control scheme is applied and the simulations are carried out in different road disturbance input conditions. Simulation results show that the present control scheme is very effective in reducing peak values of vehicle body accelerations, especially within the most sensitive frequency range of human response, and in attenuating the excessive dynamic tire load to enhance road holding performance. The stability and adaptability are also showed even when the system is subject to severe road conditions, such as a pothole, an obstacle or a step input. Compared with conventional passive suspensions and the active vehicle suspension systems by using, e.g., linear fuzzy logic control, the combined PID and fuzzy control without parameters self-tuning, the new proposed control system with GA-based self-learning ability can improve vehicle ride comfort performance significantly and offer better system robustness.

• Journal of Wetlands Research
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• v.15 no.2
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• pp.203-214
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• 2013

Knowing how many species live in a ecosystem is a major work because of the distributions of species are determined by the environmental condition. This study was carried out to investigate the distribution of vascular plants of Gonggeom-ji, located in Sangju-si, Gyeongsangbuk-do, from April to October on 2012. The vascular plants were summarized as 240 taxa including 69 families, 176 genus, 204 species, 2 subspecies, 29 varieties, and 5 forma. Among the investigated taxa, 3 taxa of Korean endemic plants were included. Based on the list of specially designated plants by Ministry of Environment, 11 taxa including Alisma orientale, Monochoria korsakowii and Nymphoides peltata were recorded. The naturalized plants were identified as 26 taxa and the ratio of naturalized index (NI) was 10.8% of vascular plants recorded. 31 taxa of hydrophytes showed 17.8% of Korea. To conservation of wetlands, we suggest that it is required to minimize for unnecessary disturbance of human and to make a strategy for effective management by continuous monitoring for ecosystem alteration.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.1
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• pp.15-20
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• 2010

It has been shown that CA repeats in the 3'-untranslated region (UTR) of bcl-2 mRNA contribute the constitutive decay of bcl-2 mRNA and that hnRNP L (heterogenous nuclear ribonucleoprotein L) interacts with CA repeats in the 3'-UTR of bcl-2 mRNA, both in vitro and in vivo. The aim of this study was to determine whether the alteration of hnRNP L affects the stability of bcl-2 mRNA in vivo. Human breast carcinoma MCF-7 cells were transfected with hnRNP L-specific shRNA or hnRNP L-expressing vector to decrease or increase hnRNP L levels, respectively, followed by an actinomycin D chase. An RT-PCR analysis showed that the rate of degradation of endogenous bcl-2 mRNA was not affected by the decrease or increase in the hnRNP L levels. Furthermore, during apoptosis or autophagy, in which bcl-2 expression has been reported to decrease, no difference in the degradation of bcl-2 mRNA was observed between control and hnRNP L-knock down MCF-7 Cells. On the other hand, the levels of AUF-1 and nucleolin, transacting factors for ARE in the 3'UTR of bcl-2 mRNA, were not significantly affected by the decrease in hnRNP L, suggesting that a disturbance in the quantitative balance between these transacting factors is not likely to interfere with the effect of hnRNP L. Collectively, the findings indicate that the decay of bcl-2 mRNA does not appear to be directly controlled by hnRNP L in vivo.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.779-790
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• 2007

Objective : Although chronic non-bacterial prostatitis is a common disease, it is very difficult to treat effectively. GLS (Gleditsiae Spina) has traditionally been used in treatment of urinary tract inflammation and voiding disturbance. In this study, we investigated the therapeutic effects and action mechanism of GLS in the rat model of non-bacterial prostatitis induced by castration and testosterone treatment. Method : We observed four experimental objects of normal group, control group, testosterone group, and GLS group. Rats were treated with 17$\beta$-estradiol after castration for induction of experimental non-bacteral prostatitis, which is similar to human chronic prostatitis in histophatological profiles. GLS and testosterone were administered as an experimental specimen and a positive control, respectively. The prostates were evaluated by histopahological parameters including the epithelial score and epithelio-stromal ratio for glandular damage. Also, the prostates were observed by hematological alterations of WBC, RBC, hemoglobin, hematocrit and platelet. Results : While prostates of control rats revealed severe acinar gland atrophy and stromal proliferation, the rats treated with GLS showed a diminished range of tissue damage. Epithelial score was improved in GLS over that of the control. The epithelial-stromal ratio was lower in GLS when compared to that of the control. Conclusion : These findings suggest that GLS may protect the glandular epithelial cells. We concluded that GLS could be a useful remedy agent for treating chronic non-bacterial prostatitis.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.2
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• pp.52-61
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• 2001

At least, there are intense pressures on the natural habitats from various disturbance, including urbanization, extension of industrial area, and road construction. These human land use result in fragmentation of landscape and natural habitat. The ecological consequences of habitat fragmentation include the direct effects of habitat loss and the indirect effects of reduced inter-patch dispersal. The decline of biological diversity has been rapidly declined by the habitat loss and fragmentation. Conservation strategists should consider not only the habitat amount of that must be preserved, but also the spatial configuration of habitat across the landscape. But, the paucity of available data for most species forces landscape ecologists to develop the concept, model, and theory. The developed theories are often misused in academic papers and practical applications. The development history, presumption of concept, model, theory is ignored. This tendency have leaded to failure of landscape restoration and the use of theory in conservation practice have come under increasing attacks. This paper will highlight the ecological theory that have proven the most influential in landscape ecology, restoration and conservation : the theory of island biogeography, the theory of nested subset analysis, minimum viable population(MVP), the theory of metapopulation dynamics. And, it find the problem and usefulness of four theory in application to real world. Consequently, the understanding of theoretical implication about landscape ecological theory is required. We must carefully apply the theory after examining the problem and availability of various theory because of no existence of only one general theory.