• Journal of Institute of Control, Robotics and Systems
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• v.13 no.7
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• pp.656-663
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• 2007

A new dynamic balancing algorithm has been proposed to minimize the number of sensors necessary for the horizontal balancing of the mobile inverted pendulum while maintaining the same level of the commercial performance. The inverted pendulum technique is getting attention and there have been many researches on the Segway since the US inventor Dean Kamen commercialized. One of the major problems of the Segway is that many sensors are required for the control of the Segway, which results in the high price. In this research, a single gyro and a tilt sensor are fused to obtain the absolute tilt information, which is applied for the control of the mobile inverted pendulum. A dynamic balancing technique has been developed and applied for a robust control system against disturbances. The intelligent handling and stable curving of the Segway as a next generation mobile tool are verified with a human loading.

• Journal of Mechanical Science and Technology
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• v.20 no.11
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• pp.1823-1833
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• 2006

An immune algorithm is a kind of evolutional computation strategies, which is developed in the basis of a real immune mechanism in the human body. Recently, scientific or engineering applications using this scheme are remarkably increased due to its significant ability in terms of adaptation and robustness for external disturbances. Particularly, this algorithm is efficient to search optimal parameters against complicated dynamic systems with uncertainty and perturbation. In this paper, we investigate an immune algorithm embedded Proportional Integral Derivate (called I-PID) control, in which an optimal parameter vector of the controller is determined offline by using a cell-mediated immune response of the immunized mechanism. For evaluation, we apply the proposed control to mitigation of vibrations for nonlinear structural systems, cased by external environment load such as winds and earthquakes. Comparing to traditional controls under same simulation scenarios, we demonstrate the innovation control is superior especially in robustness aspect.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.44-46
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• 2001

In vitro produced (IVP) embryos produced by in vitro fertilization (IVF) often exhibit wide variations in developmental competence and viability, considerably more than are exhibited by embryos that develop in vivo. These anomalies in IVP embryos may be due to heterogeneity of oocyte quality, suboptimal culture conditions, disturbances in gene expression, or most likely a combination of these factors (Ho et al., 1994; Roth et al., 1994; McKiernan and Bavister, 1998; Hasler, 1998; Schramm and Bavister, 1999; Doherty et al., 2000; Hyttel et al., 2000; Niemann and Wrenzycki, 2000; Wrenzycki et al., 2001). In research studies or in clinical applications with domesticated animals, cats, non-human primates and humans, oocytes used for IVF are usually collected from a heterogeneous cohort of ovarian follicles that include oocytes which normally might not be ovulated and/or are deficient in developmental competence. (omitted)

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.3
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• pp.841-852
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• 2015

The objectives of this study are to amend of the Small Stream Maintenance Act. In general, small streams have diverse ecological and social characteristics because they are extensively formed across watersheds over time. However, small streams in Korea have been significantly degraded primarily because of human disturbances including stream maintenance activities. Especially, covered streams are majority problem in the Small Stream Maintenance. In order to improve this problem, the Small Stream Maintenance Act be amended to the Small Stream Management Act.

• Proceedings of the KIEE Conference
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• 2009.04b
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• pp.88-90
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• 2009

Extremely-Low-Frequency(ELF) magnetic fields are generated around power cables and bus bars in power systems. Such the stray fields may cause disturbances to nearby electronic apparatus and affect even human health. In order to seeking out a proper way to reducing the fields, the first thing to do is to accurately predict field distribution around analysis models of interest. Then, optimization techniques should be applied for finding a more improved design than the initial one. To achieve this goal, commercial electromagnetic software, MagNet, is combined with evolution strategy algorithm. For verification of the proposed method, three-phase power line cables and busbar systems have been tested.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.126-142
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• 2020

Background: Most of the Pinus densiflora forests, occupying the largest area, have been restored in South Korea since the 1970s. As young pioneer forests, the succession process is under way. Since the forests are distributed nationwide and are vulnerable to disturbances, the process may differ depending on the geography and/or site conditions. Therefore, we reviewed the direction, the seral communities, and the late-successional species of progressive and disturbance-driven succession nationwide in the cool-temperate zone through meta-analysis and empirical observations. Main text: As a result of a meta-analysis of the direct succession and vertical structure, we found that the P. densiflora forest is in a directionally progressive succession, changing to the broadleaved forest after forming a mixed forest with its overwhelming successor, Quercus species (particularly Q. mongolica and Q. serrata). In dry stands in a relative sense, the Quercus species was favored occupying over 80% of the abundance of the succeeding species. Therefore, in dry stands, it is presumed that Quercus-dominated stage would last for a long time due to the current dominance and long life span, and eventually, it settles as Quercus-broadleaved forest with a site change. Contrary to this, it is presumed that in mesic stands where Quercus species do not occur or have low abundance, the late-successional broadleaved species settle early to form a co-dominant forest with multiple species. Due to geographical limits, the species composition of the two late-successional forests is different. Disturbances such as insect pests and fire retrogressed vulnerable P. densiflora forest for a while. However, it was mostly restored to the Quercus forest and is expected to be incorporated in the pathway of the dry stand. Conclusions: We revealed the succession process of P. densiflora forests according to geography and moisture and found that stand moisture had a decisive effect on the species and abundance of the successor. Although the P. densiflora forest is undergoing structural changes, the forest is still young; so within a few decades, physiognomy is not likely to change. Therefore, the decrease in the forest area may be due to other causes such as disturbances and forest conversion rather than due to succession.

• Korean Journal of Plant Taxonomy
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• v.50 no.2
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• pp.199-226
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• 2020

Hwangmaesan Mt. (1,108 m) is rich in forest biodiversity and is a part of the Sobaek mountain range located in Hapcheon-gun, Gyeongsang-do in Korea. Unfortunately, the biodiversity and ecosystem integrity of Hwangmaesan Mt. have recently been threatened by heavy human disturbances. We conducted thirteen field surveys between March and October of 2019 to investigate the vascular flora in Hwangmaesan Mt. Through this extensive survey, we found 628 taxa consisting of 106 families, 349 genera, 554 species, 16 subspecies, 48 varieties, and 10 forma. Based on a comparative analysis between the present findings and former flora reports, our results showed an increase by 28 percent in the number of taxa observed. Of the 628 taxa, dicotyledons made up the largest group (477 taxa, 76.0%) followed by monocotyledons (120 taxa, 19.1%). Endemic plants consisted of 16 taxa, with rare plants designated by the Korea Forest Service numbering 14 taxa. Ten taxa were listed on the Red list by the Ministry of the Environment. The floristic target species designated by the Ministry of the Environment numbered 75 taxa, whereas there were 42 taxa of invasive plants.

• The Research Journal of the Costume Culture
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• v.7 no.3
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• pp.50-57
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• 1999

Folk belief, which originated with the rise of human existence is a fundamental and comprehensive mode of living that reflects sociocultural conditions. Adherents of folk belief accept a certain thing to be true and real without scientific authority and absolute certainty. Taboo can be seen as a king of folk belief. The object of this study is to examine the taboos in relation to the manufacturing process and the quality of the shroud and to shrouding customs. I will also try to find out the meaning and significance in this. Through this task, I hope to contribute to the enhanced understanding of the cultural characteristics, the spiritual life, and the views on after life of the Korean people. In Korea, it is considered to be propitious to prepare the shroud on the intercalary month of the leap year , as it allows one to enjoy longevity healthy and sound. Moreover, as this belief gives credence and repose while preparing for the “final departure”, this custom is relatively well observed. From the taboo concerning leap months, we infer that death as viewed as a commencement of a new life, which reveals a positive view on afterlife. This can be seen as a return to the origin of anti-universal space in this “bonus” month of anti-universal time. Taboos on the manufacturing process of the shroud is related to the belief that it allows the deceased to go the nest world without any hesistation or disturbances. This symbolizes the immortality of the human soul: I. e. that the human spirit does not end in this world but continues on to the next. Taboos concerning the preparation process of the shroud as well as various other taboos are related to the belief that preparation for the shroud should be done in sincerity and secredness with a thoughtful consideration for the deceased. This can be perceived as an implication to sanctity for the dead.

• Journal of the Korean Institute of Landscape Architecture
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• v.34 no.3 s.116
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• pp.1-11
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• 2006

This study analyzed characteristics of natural and human environments in Chuncheon's Gongji stream, and suggested nature-friendly planning strategies for self-purification of water quality, biodiversity improvement and conservative waterfront recreation. The environmental analysis included streambed structures, floodplain soils, water quality, vegetation, wildlife, and human facilities. Natural colonization of vegetation for the middle section of the study stream was obstructed by a straightened concrete revetment of baseflow channel, and vehicle movement and concrete parking lots across the floodplain. These human disturbances also deteriorated the naturalness of the stream landscape and limited habitation of bird species. However, natural sedimented wetlands in half of the channel width for the lower section of the stream contributed to a desirable vegetational landscape and greater bird occurrence. Based on BOD measurements, water quality of the stream fell under class $II{\sim}III$ of the stream water-quality standard, but it was worse around sewage outlets due to incomplete sewage collection especially during the dry season. Dominant fish species included typical inhabitants of good water-quality streams that are tolerant of adverse habitat changes. Nature-friendly planning strategies were established based on analysis of the environmental characteristics. They focused on not merely spatial zoning and layout divided into four zones - preservation, partial preservation, conservation and use -, but close-to-nature channel revetment techniques, natural water-purification facilities, biotope diversification, and water-friendly recreation and circulation. Strategies pursued both renewal of stream naturalness and hydraulic stability of streamflow by minimizing transformation of natural channel micro-topography and biotope, and by reflecting natural traces of streambed structures such as revetment scour and sedimentation.

• Korean Journal of Cleft Lip And Palate
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• v.4 no.1
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• pp.39-43
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• 2001

The design of osteotomy plane in orthognathic surgery has been developed to diminish the nerve injury. Intraoral Vertico-Sagittal Ramus Osteotomy (IVSRO) is the one of the best way to minimize untoward results, which is designed not to expose the lingula. We evaluated the nerve damage before and after with current perception threshold (CPT) test which is modem and numerically expressible way of nerve damages. Sixty patients underwent IVSRO since 1998 were evaluated. They were divided into 2 groups; one group underwent IVSRO only, and the other underwent IVSRO plus genioplasty. The both groups were evaluated with CPT test 1 week before surgery, and 1, 3 and 6 months after surgery. The CPT test was performed on A-beta, A-delta and C fiber respectively. 111e result showed that the recovery of sensory function of damaged nerve fibers was observed at the period of three to six months after surgery. There was no impairment of nerve function after only the IVSRO . But there were sensory disturbances in cases of additional genioplasty group. We thought that one of major factors on nerve damages were exposure of nerve and traction injury during genioplasty.