• Journal of international Conference on Electrical Machines and Systems
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• v.1 no.1
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• pp.104-113
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• 2012

Wind farm grid codes require wind generators to ride through voltage sags, which means that normal power production should be re-initiated once the nominal grid voltage has been recovered. Doubly Fed Induction Generator (DFIG) based wind farm is gaining popularity these days because of its inherent advantages like variable speed operation and independent controllability of active and reactive power over conventional Induction Generator (IG). This paper proposes a new control strategy using DFIGs for stabilizing a wind farm composed of DFIGs and IGs. Simulation analysis by using PSCAD/EMTDC shows that the DFIGs can effectively stabilize the IGs and hence the entire wind farm through the proposed control scheme by providing sufficient reactive power to the system.

• Bulletin of the Korean Chemical Society
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• v.30 no.3
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• pp.687-690
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• 2009

A series of novel 1,3-diallyltrisulfane analogues were synthesized and assayed in vitro for antimicrobial activity against Gram positive, Gram negative bacteria and fungi. The antimicrobial activity of the 1,3-diallyltrisulfane derivatives showed, on the whole, very potent towards all the tested Gram positive, Gram negative and fungi (MIC ranging from 4 to 256 μg/mL). 1,3-Di(pent-4-enyl)trisulfane 3b and 1,3-bis(3-methylbut-2-enyl)trisulfane 3e exhibited the strongest antibacterial activity among all the compounds, and both of them were more active than 1,3-diallyltrisulfane (DATS). Results indicated the relationship of either carbon number or lipophilicity with antimicrobial activity presented “V” shape. These observations provided some predictions in order to further design 1,3-diallyltrisulfane derivatives with antimicrobial activity.

• Speech Sciences
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• v.7 no.4
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• pp.73-82
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• 2000

The perceptual judgement of nasality is still used in the assessment of velopharyngeal incompetence, but it should not be the sole criterion for speech nasality. Objective procedures may be used to assess velopharyngeal function, for example, nasometer, aerodynamics, x-ray, electromyography, nasoendoscopy, and videofluoroscopy can be utilized. The nasometer employs noninvasive measurement methods and measures with high levels of accuracy. The aim of this study was to obtain comprehensive nasalance data for Korean children, aged 7 years, and to investigate any gender differences within that age group. The results were as follow: 1. Statistically, gender has no significant effect on the nasalance of vowels /a/, /i/, /o/, /u/, /je/, /wi/) but the nasalance of the vowels /e/, /ja/) was higher in males (p<0.05). 2. There was no statistically significant effect of gender in plosives /p/, /ph/, /p'/, /t/, /th/, /t'/, /k/, /kh/, /k'/), affricatives /c/, /ch/, /c'/), and fricatives /s/, /s'/, /$\int$/). 3. The nasalance of the nasal consonants, /m/, /n/, /an/) is higher in males and only /n/, /an/ were statistically significant (p<0.05).

• Speech Sciences
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• v.13 no.3
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• pp.121-132
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• 2006

In Hangeul, the graphemes of syllables are organized in horizontal, vertical and mixed (both horizontal & vertical) orientations, and the graphemic position of consonant(s) and vowel(s) within a each syllable needs to be maintained within a square pattern. We investigated the characteristics of writing errors of 9 stroke patients with right hemisphere (RH) lesions and compared it to the performances of 15 normal subjects. The subjects were asked to write to dictation of 90 Korean syllables. One of the interesting findings was that our patients manifested visuospatial errors which are not commonly observed in other language-speaking (e.g., English) patients due to the unique syllabic organizations of Korean writing system. The prominent errors in the RH group could be explained by the impaired RH which normally controls the visuospatial functions.

• Journal of Korean Association for Spatial Structures
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• v.4 no.4 s.14
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• pp.99-111
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• 2004

An exact solution procedure is formulated for the free vibration and buckling analysis of rectangular plates having two opposite edges simply supported when these edges are subjected to linearly varying normal stresses. The other two edges may be clamped, simply supported or free, or they may be elastically supported. The transverse displacement (w) is assumed as sinusoidal in the direction of loading (x), and a power series is assumed in the lateral (y) direction (i.e., the method of Frobenius). Applying the boundary conditions yields the eigenvalue problem of finding the roots of a fourth order characteristic determinant. Care must be exercised to obtain adequate convergence for accurate vibration frequencies and buckling loads, as is demonstrated by two convergence tables. Some interesting and useful results for vibration frequencies and buckling loads, and their mode shapes, are presented for a variety of edge conditions and in-plane loadings, especially pure in-plane moments.

• Steel and Composite Structures
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• v.20 no.2
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• pp.413-429
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• 2016

A theoretical method to predict the interfacial stresses in the adhesive layer of reinforced concrete beams strengthened with externally bonded carbon fiber-reinforced polymer (CFRP) plate is presented. The analysis provides efficient calculations for both shear and normal interfacial stresses in reinforced concrete beams strengthened with composite plates, and accounts for various effects of Poisson's ratio and Young's modulus of adhesive. Such interfacial stresses play a fundamental role in the mechanics of plated beams, because they can produce a sudden and premature failure. The analysis is based on equilibrium and deformations compatibility approach developed by Tounsi. In the present theoretical analysis, the adherend shear deformations are taken into account by assuming a parabolic shear stress through the thickness of both the reinforced concrete beam and bonded plate. The paper is concluded with a summary and recommendations for the design of the strengthened beam.

• Journal of Ginseng Research
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• v.18 no.3
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• pp.187-190
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• 1994

The pith and xylem parts of fresh root that turned into inside-white during processing for red ginseng was investigated under scanning electron microscope in comparison with the sa31e position of fresh root processed into normal reddening. In the inside-white part starch storage cells remain mostly in vacancy or with small number of starch granules and with large hollow by missing cell membranes between cells. Many starch seed granules appeared on the surface of storage cell wall in the inside-white part. Fresh root sample showed better picture than dried powder.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1991.06a
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• pp.21-21
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• 1991

구개열이나 구개부전이 있는 경우, 흔히 비 정상적인 비음을 접할 수 있는데 이러한 구조이상과 구음이상간의 관계를 밝히는데 있어서 비음에 대한 객관적인 평가방법이 요구된다. 여러 객관적 지표로서의 가능성 중에 음향학적 분석이 많이 시행되었는데 이 방법도 개인별 공명구조의 차이에 기인한 변동이 심하므로 그 효용의 관계가 있었다. 저자들은 이러한 개인별 차이를 줄이기 위해 정상 성인 남자 20명에서 한국 모음 /a/, /i/, /u/, /e/, /o/에 대하여 각각 정상 발음, 인공적으로 일으킨 비폐색, 비개방음을 음향학적으로 분석하여 보았다. 결과, Formant의 변화를 관찰하였고 비음의 객관적 지표로써 이용 가능성을 알 수 있었다.

• Journal of the Korea Society of Computer and Information
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• v.20 no.11
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• pp.127-133
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• 2015

In this paper, we propose that college counselors be more knowledgable of adult ADHD symptoms and develop better understandings of subtypes of the disorder. The findings in this study show that college students with different subtypes of ADHD symptoms experience different types of psychological maladjustment as well as different levels of psychological distress. Specifically, combined-type trait group show the highest levels of each of subscale of SCL-90-R among the other groups (i.e., normal, predominant inattentive subtype, hyperactive-impulsive type). Furthermore, combined typed trait group show significantly higher levels of animosity and paranoid ideation than the others. Therefore, college counselors need to provide effective interventions addressing intense emotion and cognitive distortion among college students with ADHD combined symptoms.

• YAKHAK HOEJI
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• v.31 no.5
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• pp.253-265
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• 1987

To develop hybridomas secreting monoclonal antibodies to be used as unlimited sources of reagents indispensable for the diagnosis and treatement of leukemic malignancy, a monoclonal antibody was generated to human pre-T leukemia cells (Jurkat). Hybridomas were produced against Jurkat cell line by fusing spleen cells from hyperimmunized mice with murine plasmacytoma cells (P3$\times$63Ag8. V653). One monoclonal antibody derived from this fusion, designated DMJ-2 was reactive with T-cell lines (Jurkat, Molt-4 and RPMI-8402) and normal peripheral E-rosette forming T cells, but unreactive with B-cell lines (Daudi, Nalm-6) and non-T, non-B cell line (K562). Conclusively DMJ-2 reactive with mature and immature T-lineage lymphoid cells.