• Proceedings of the KIPE Conference
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• 2007.11a
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• pp.103-107
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• 2007

In doubly fed induction generators (DFIGs), control of rotor currents allows for adjustable speed operation, active, and reactive power control. This paper presents a DFIG control strategy that enhances the active and reactive power control with controllers that can compensate for the errors caused by current measurement path in the DFIG system. The errors can be divided into two categories: offset and scaling errors. These can induce the speed, active, and reactive power pulsations, which are one and two times the fundamental slip frequency in the DFIG. And these undesirable ripples can do the DFIG harm. In this paper, a new compensation algorithm is proposed. Therefore, the proposed algorithm has several advantages: to implement is easy; it require less computation time; it is robust with regard to the variation of the induction generator parameters. In this paper, a new algorithm is introduced by using the integral of phase currents to measure the current ripples of rotor-side converterin the DFIG system. The experiment results are shown the effectiveness of the proposed method.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.2
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• pp.261-267
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• 2013

The purpose of this study was to examine the psychometric structure of Sasang typology with four personality measures and examine the construct validity of Sasang Personality Questionnaire (SPQ). We measured biopsychological traits of 104 university students using SPQ, Temperament and Character Inventory (TCI), NEO-Personality Inventory (NEO-PI) and Myers-Briggs Type Indicator (MBTI). The construct validity of SPQ was analyzed with TCI, NEO-PI and MBTI using Pearson's correlation. The temperament features of each Sasang groups were compared with Analysis of Variance and Profile Analysis. The SPQ showed significant correlation with TCI Novelty-Seeking (r=.398), TCI Harm-Avoidance (r=-.333), TCI Reward-Dependence (r=.465), TCI Self-Directedness (r=0.340), NEO-PI Extraversion (r=0.489) and MBTI Extraversion-Introversion (r=-0.509). The SPQ, TCI and NEO-PI revealed significant differences between Sasang constitutional groups. We examined the temperament construct of the Sasang typology and the validity of SPQ with well established western biopsychosocial instruments. This study would contribute to the objective studies on the biopsychosocial mechanism of Sasang medicine.

• Journal of the Korean Society of School Health
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• v.23 no.2
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• pp.181-191
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• 2010

Purpose: The purpose of this study is to analyze the drinking status and to identify the impacts of depression, temperament, characteristic on drinking status in the vocational high school students. Methods: By using stratified sampling, 416 vocational high school students in Gangwon Do were selected and surveyed through self -administered questionnaires. Data were analyzed by SPSS 12.0 using $x^2$-test, t-test, ANOVA, Pearson correlation coefficient and multiple regression. Results: 88% of students had experienced of drinking. Depression was observed 59.1% of students from light to severe depression score. There was a positive correlation among drinking, the school records, novelty seeking, reward dependence and persistence. Also, there was a negative correlation among drinking, economic status, harm avoidance. The significant predictors of drinking were school records, depression, novelty seeking and persistence. Conclusion: These results suggest that vocational high school students who have the factors identified in this study are regarded as having the potential to drink. The results of this study can provide the information for the development of the health promotion program.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.2
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• pp.143-145
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• 2005

Lamerin breed of the silkworm, Bombyx mori L. for Northeastern India hosts a vertically transmitted microsporidian parasite for generations, which does not harm significantly the cocoon production. The transversally infected progenies do not exhibit marked external sign or symptom. The microspordian causes inapparent infection and over $(80\%)$ of the infected progeny survives and spin cocoons. There is possibility of co-existence between the breed and the associated micosporidian parasite. To evaluate the impact of the microsporidian on breed the present study was conducted in respect of tranovarial transmitted (observed as T1), secondarily infected (observed as T2) and healthy silkworm (observed as T3). The larval and pupal mortality was $12\%$ and $6\%$ in T1 and $10\%$ and $3\%$ in T2 batch, while in case of T3 batch there was no mortality. Significant changes were also observed in single cocoon weight, single shell weight, denier, reelibility, raw silk recovery $\%$ and neetness. There is no significant impact of the infection on the fecundity and hatchability. The hatchability of the eggs laid by healthy or infected moths are equall as much as control but the progeny had the infection transmitted from the parent.

• Journal of Sensor Science and Technology
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• v.28 no.6
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• pp.395-401
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• 2019

This paper proposes a method for estimating the location of a magnetized tip that is inside a non-transparent space or body by using arrayed giant magnetoresistance (GMR) sensors. In general, an object located in such an opaque space can be detected using X-rays, magnetic fields, ultra-sonic sensors, etc., depending on its characteristics. X-ray is mostly used for medical purposes but frequent exposure to it could cause harm to patients as well as doctors. In this study, how well a GMR sensor is applicable instead of an X-ray is investigated. The sensor's voltage output is experimentally fitted to distance with a relationship of 3rd degree polynomial. To detect a small magnetized tip with 900 Oe inside a human body, a 2×2 arrayed GMR sensor and a location estimation algorithm based on information acquired from four sensors is developed. Evaluation tests show that the suggested method is applicable to limited cases with a distance less than 33-55 mm, and the location of a magnet tip is estimated relatively well with an error less than 1.5 mm.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.6
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• pp.107-116
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• 2006

Recently, it has been important not only to evaluate environmental effects but also to assess cumulative and comprehensive effects by the development projects. This paper concentrates on temporal and spatial cumulative impacts on Suji district in Yongin, Gyunggi-do. This paper adopted two methods to assess the cumulative impacts. First, it assesses the temporal change of forest patch size and land cover according to the patch size. Second, it compares housing development zones with the neighborhood. The result of the research appears that the damage is very serious, especially in small forest. The Forest area is changed to farm land, most of them become to built-up area later. In addition, it is assessed that the secondary housing development projects did more harm than the initial one. By assessing the cumulative impacts on Suji district, this research suggests to minimize two kinds of solutions : comprehensive environmental assessments in regional unit and regulation on total forest quantity.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.1
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• pp.155-170
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• 2016

This study established the definition of invasive disturbance species for a sustainable management and biodiversity, and derived the influence factors caused by the species. To define the species, the paper reviewed similar words such as alien species and invasive species, using standard definitions. Also reviewed the results of recent research on the factors of the species. The paper defined the invasive disturbance species as an species whose establishment and spread threaten ecosystems, habitats or species with economic or environmental harm including native and non-native. Through the reviews, The factors were classified as geographic (altitude, slope, and soil, etc.), climate (temperature, precipitation, climate change, etc.) and, anthropogenic (land use, population, road, and human activity, etc.), and species & vegetation structure (species property, local-species richness, and canopy, etc.). Especially, human activity such as urbanization and highways may be associated with both higher disturbance and higher propagule pressure. In the further study, it is required development of mitigation strategies and vegetation structure model against invasive disturbance species in urban forest based on this study.

• Korean Journal of Clinical Laboratory Science
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• v.47 no.1
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• pp.51-58
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• 2015

Ethanol has long been implicated in triggering apoptotic neurodegeneration. Alcohol also may indirectly harm the fetus by imparing the mother's physiology. We examined the effects of ethanol on immature brain of mice. Three-weeks-old female ICR strain mice daily intraperitoneally injected with ethanol at the concentration of 4 and 20% in saline for 0, 6, and 24 hours and 1 and 4 weeks. The mice were weighted and sacrificed, and the brains were ectomized for the present histological, immunohistochemical and TUNEL assays. Based on the histologic hematoxylin and eosin stain, immunohistochemical expression of glutamate receptor protein and neuronal cell adhesion molecule (NCAM) were evaluated. The cerebral cortex of the ethanol-treated group showed few typical symptoms of apoptosis such as chromosome condensation and disintegration of the cell bodies. TUNEL staining revealed DNA fragmentation in the 6 and 24 hours. This results demonstrated that acute ethanol administration causes neuronal cell death. I found that either glutamate receptor inhibition or activation could induce cerebellar degeneration as ethanol effect. Neuronal death also can be induced by excess activity of certain neurotransmitter, including glutamate. Neurons must establish cell-to-cell contact during growth and development in order to survive, migrate to their final destination, and develop appropriate connections with neighboring cell. Purkinje cell in cerebellar are especially vulnerable to the cell death and degeneration. After ethanol treatment in cerebellar, NCAM had decreased by 4 weeks. This result suggest that apoptosis seems to be involved in the slow elimination of neuron and cerebellar degeneration.

• Journal of the Korean Society of Safety
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• v.27 no.5
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• pp.16-21
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• 2012

The purpose of this study is to try to find the risk of roller(mixing mill) in working site. In order to achieve the purpose, accident analysis and survey was carried out. This analysis revealed that average of loss days is 334.3 by roller jamming accident and 229.2 by other causes. It means jamming accident entails serious bodily harm. According to our research, we realize that most of rollers have some risk of the jamming accidents. It is simply because the roll gap in the roller is not more than 10cm. It also does not meet minimum distance so as to avoid the risk for jamming accident by KS. Furthermore, 28% of rollers have only one switch and 40% of rollers have two switches operating emergence stop equipment so as to reduce the risk of jamming accidents. Therefore, we presume that it is very difficult to turn on the switch of emergence stop equipment when they confront the accident because most of engineers are working alone.

• Ocean and Polar Research
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• v.24 no.4
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• pp.501-524
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• 2002

Article 121 of the UNCLOS stipulates the regime of islands and grants different jurisdictions to islands and rocks. Especially, paragraph 3 gives different definitions and distinguishes the legal status of between islands and rocks. That is, rocks, which cannot sustain human habitation or economic life cannot have their own EEZ, continental shelf or the great-sphere maritime jurisdiction. In this paper various theories and state practicess on islands and rocks are examined with reference to Article 121 of UNCLOS. Also, the status of Dokdo as a rock or an island is examined in accordance with the interpretation of Article 121 of UNCLOS. National legislations, practices, and many scientific opinions are often contradictory and controversial with respect to the interpretation of Article 121 of the UNCLOS. However, it is believed that Article 121 of UNCLOS, particularly paragraph 3 has to be interpreted more strictly. That is because the highly developed modem scientific technology can be meaningless when the criteria of Article 121 of UNCLOS are to be inappropriately applied. Insular figures like ${\ulcorner}rocks{\lrcorner}$ could bring the inequitable effects disadvantageous toward the other party when the maritime delimitation is applied. Claiming and Intentionally extending maritime zone of a coastal states by assigning EEZ for small insular figures like ${\ulcorner}rocks{\lrcorner}$ is over-zealous nationalism which is illegal, and such practices must be recognized as actions bringing great harm to the neighboring nations and demise of the sprit of all mankind.