• Title/Summary/Keyword: gi transformation

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A fault prevention diagnostic of power transformer using Frequency Response Analysis (주파수 응답 분석(FRA)을 이용한 전력용 변압기 고장예방 진단)

  • Cho, Yun-Haeng;Lim, Tae-Young;Kim, Jong-Seon;Kim, Gi-Il;Ahn, Kwang-Won;Lim, Seong-Joo
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.463-464
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    • 2011
  • Currently, different kinds of diagnosis and inspection technologies are applied to prevent the internal mechanical transformation of transformers. For example, examination of internal Partial Discharge of transformer, analysis of transformer oil gas, and measurement Frequency Response Analyzer(FRA) are used to diagnose defect. Especially, diagnosis technique through Frequency Response Analyzer(FRA) has been used and developed from 1960, when it was first introduced, till now to become an important tool to examine presence of defect and to prove quality of machines for the most electric machine producers electric power company in the world. However, diagnosis through FRA is still in introduction level in Korea and the application method for FRA is not established yet. For that reason, study about the application of domestic electric installation according to the FRA is needed. It is expected that the study play an important part in the prevention of defect due to the internal transformation of transformer by introducing measurement theory, providing measurement method, and analyzing application cases.

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Synthesis and Phase Transformation Behavior of YAG Powders by a Mechanochemical Solid Reaction (기계화학적 고상반응에 의한 YAG 분말의 합성 및 상 형성 거동에 관한 연구)

  • Jung Hyun-Gi;Hwang Gil-Ho;Lim Kwang-Young;Lee Young-Hun;Kang Sung-Goon
    • Journal of Powder Materials
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    • v.13 no.4 s.57
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    • pp.243-249
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    • 2006
  • Yttrium aluminum garnet (YAG) powders were synthesized via mechanochemical solid reaction using $Y_2O_3$ with three types of aluminum compounds. $Y_2O_3$ reacted mechanochemically with all A1 compounds and formed YAM (yttrium aluminum monoclinic), YAG and YAP (yttrium aluminum perovskite) phases depending on the starting materials. The ground samples containing ${\gamma}-A1_2O_3$ showed the best reactivity, whereas the ground sample containing A100H, which had the largest surface area, exhibited pure YAG after calcination at $1200^{\circ}C$. The sample containing Al had the least reactivity, producing YAP along with YAG at $1200^{\circ}C$. The types and grinding characteristics of the starting materials and grinding time are believed to be important factors in the mechanochemical synthesis of YAG.

The Fashion Formative Characteristics and Meanings in the Tech Fatale Types of the Post Digital Generation - Focusing on the Female Models of the Mobile Advertisements - (포스트 디지털 시대의 Tech Fatale 유형에 나타난 패션 조형특성과 내적 의미 - 휴대전화 광고의 여성모델을 중심으로 -)

  • Kim, Ha-Lim;Kwon, Gi-Young;Lee, Shin-Hee
    • Fashion & Textile Research Journal
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    • v.10 no.5
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    • pp.721-730
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    • 2008
  • The purpose of this study is to analyze the tech fatale fashion image in female models of mobile advertisements and to find the fashion characteristics. The tech fatale emerging as new culture code is a compound word of the femme fatale and technology. It is characteristics of the femme fatale, the post digital culture and the female leadership. The findings of the study were as follows : The tech fatale types were the independence, the transformation and the tradition. The independence was a self expression, appealed to visual image, was showed the coating fabric, denim, space look and street fashion and reflected the creativeness and digital generation. The transformation appealed to sexuality and was showed luster fabric, exposure, body-conscious, glam look. The voluptuous beauty represented the pride of the post digital generation. The tradition appealed to emotion and was showed pale color, simple line, soft texture fabric and a feminine Image. The meanings of tech fatale were the imagination, the public, the duality, the game, the purity and the recurrence. The formative characteristics reflect the mind of post digital generation who is against authority and pursues the human being worth such as the identity establishment and the pure emotion.

Distortion Correction of Boundary Lines in a Tunnel Image Captured by Fisheye Lens (어안렌즈 터널영상의 경계선 왜곡 보정)

  • Kim, Gi-Hong;Jeong, Soo
    • Journal of Korean Society for Geospatial Information Science
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    • v.19 no.4
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    • pp.55-63
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    • 2011
  • Having a wide angle of view, a fisheye lens is useful for obtaining images of the inside wall of a tunnel. A circular fisheye tunnel image can be transformed into a familiar rectangular image by applying the concept of cylindrical projection. This projection transformation causes several types of distortions in the projected image. This paper discusses the distortion on the boundary lines between smoothly curved wall and flat ground. We analyzed the cause of this boundary distortion, developed transformation model, and derived a correction formular. A distortion correction software programmed in Visual C++ applied to projected image. Consequently, boundary-corrected image could be obtained. Research into other distortions of projected image will helpful in obtaining tunnel image that resembles real tunnel from fisheye tunnel image.

High-frequency Plant Regeneration from Mature Seed-derived Callus Cultures of Orchardgrass (오차드그래스 성숙종자로부터 캘러스 유도 및 고효율 식물체 재분화)

  • Lee, Sang-Hoon;Lee, Dong-Gi;Kim, Jin-Soo;Lee, Byung-Hyun
    • Journal of Plant Biotechnology
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    • v.30 no.4
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    • pp.341-346
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    • 2003
  • In an effort to optimize tissue culture conditions for genetic transformation of orchardgrass (Dactylis glomerata L.), an efficient and high-frequency plant regeneration system from seed-derived calli was established. Embryogenic calli induced on MS medium containing 3mg/L 2,4-D and 0.1mg/L BA had significantly improved regeneration ability. Plant regeneration rate was 92% when embryogenic calli were cultured on N6 medium supplemented with 1mg/L 2,4-D and 3mg/L BA. Among three kinds of medium, MS and N6 medium were optimal for embryogenic callus induction and plant regeneration, respectively. Ho difference in callus induction frequency was observed among four cultivars of orchardgrass, however, "Roughrider" cultivar showed higher regenerability with the frequency of 61%. Addition of maltose to the regeneration medium as a carbon source dramatically increased regeneration frequency up to 69%. A short tissue culture period and high-frequency regeneration system would be beneficial for molecular breeding of orchardgrass through genetic transformation.

Gross Error Detection and Determination of Exterior Orientation Elements in Non-metric Photos (비측량용(非測量用) 사진(寫眞)에서의 과대오차(過大誤差) 검출(檢出) 및 외부표정요소(外部標定要素) 결정(決定))

  • Yeu, Bock Mo;Sohn, Duke Jae;Park, Hong Gi
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.7 no.4
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    • pp.125-132
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    • 1987
  • The bundle adjustment used in photogrammetric data reduction is based on the collinearity condition. Photogrammetry has been used in many non-topographic applications. Due to the necessities of having fiducial marks and knowing initial approximations for interior and exterior orientation elements in bundle adjustment, it cannot be applied when non-metric cameras are used. Marzan and Karara develop the DLT(Direct Linear Transformation) program which directly transforms comparator coordinates into object space coordinates without approximate values. In this paper, several modifications of original DLT program have been made for accuracy improvement in close-range photogrammetry using non-metric cameras. In modified program, gross error detection method and computation of exterior orientation elements are incorporated, and more iterations are introdued.

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Optimization of filling process in RTM using genetic algorithm

  • Kim, Byoung-Yoon;Nam, Gi-Joon;Ryu, Ho-Sok;Lee, Jae-Wook
    • Korea-Australia Rheology Journal
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    • v.12 no.1
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    • pp.83-92
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    • 2000
  • In resin transfer molding (RTM) process, preplaced fiber mat is set up in a mold and thermoset resin is injected into the mold. An important interest in RTM process is to minimize cycle time without sacrificing part quality or increasing cost. In this study, the numerical simulation and optimization process in filling stage were conducted in order to determine the optimum gate locations. Control volume finite element method (CVFEM) was used in this numerical analysis with the coordinate transformation method to analyze the complex 3-dimensional structure. Experiments were performed to monitor the flow front to validate simulation results. The results of numerical simulation predicted well the experimental results with every single, simultaneous and sequential injection procedure. We performed the optimization analysis for the sequential injection procedure to minimize fill time. The complex geometry of an automobile bumper core was chosen. Genetic algorithm was used in order to determine the optimum gate locations with regard to 3-step sequential injection case. These results could provide the information of the optimum gate locations in each injection step and could predict fill time and flow front.

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Macroeconomic Effects of the Global Resource Crisis (글로벌 자원위기의 거시경제적 효과분석)

  • Song, Tae-Jung;Kim, Gi-Seung
    • The Journal of the Korea Contents Association
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    • v.8 no.10
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    • pp.259-267
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    • 2008
  • This research will examine the probabilities of future global resource crisis and what significance and effect will come upon our economy through the rise of the cost of resources. From now on, the lack of the supply of global resources will dull the world economic growth. Not only that, but the direction of each country's economic development will be decided by the appropriate measure to the resource crisis. If we are to sustain this inefficient industrial structure, as a country with high dependancy on foreign resources, Korea might face macroeconomic shock and the loss of industrial competitiveness. Therefore, we must increase the efficiency of the resource usage in the manufacturing industry such as the chemical and steel industry, and now is a period when we must add high value to our products. Henceforth, the structural constraints of supply will be the root cause of resource crisis. Thus, we must lead the subject of the economic agencies, such as companies and consumers, so that they will be able to adapt to a new paradigm called the fundamental lack of resources, rather than temporal crisis management. The Korean economy must adjust the environment for industry transformation to be achieved.

The extension of the largest generalized-eigenvalue based distance metric Dij1) in arbitrary feature spaces to classify composite data points

  • Daoud, Mosaab
    • Genomics & Informatics
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    • v.17 no.4
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    • pp.39.1-39.20
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    • 2019
  • Analyzing patterns in data points embedded in linear and non-linear feature spaces is considered as one of the common research problems among different research areas, for example: data mining, machine learning, pattern recognition, and multivariate analysis. In this paper, data points are heterogeneous sets of biosequences (composite data points). A composite data point is a set of ordinary data points (e.g., set of feature vectors). We theoretically extend the derivation of the largest generalized eigenvalue-based distance metric Dij1) in any linear and non-linear feature spaces. We prove that Dij1) is a metric under any linear and non-linear feature transformation function. We show the sufficiency and efficiency of using the decision rule $\bar{{\delta}}_{{\Xi}i}$(i.e., mean of Dij1)) in classification of heterogeneous sets of biosequences compared with the decision rules min𝚵iand median𝚵i. We analyze the impact of linear and non-linear transformation functions on classifying/clustering collections of heterogeneous sets of biosequences. The impact of the length of a sequence in a heterogeneous sequence-set generated by simulation on the classification and clustering results in linear and non-linear feature spaces is empirically shown in this paper. We propose a new concept: the limiting dispersion map of the existing clusters in heterogeneous sets of biosequences embedded in linear and nonlinear feature spaces, which is based on the limiting distribution of nucleotide compositions estimated from real data sets. Finally, the empirical conclusions and the scientific evidences are deduced from the experiments to support the theoretical side stated in this paper.

Optimization of Agrobacterium-mediated transformation procedure for grapevine 'Kyoho' with carrot antifreeze protein gene

  • Shin, Hye Young;Kim, Gi Hoon;Kang, Sang Jae;Han, Jeung-Sul;Choi, Cheol
    • Journal of Plant Biotechnology
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    • v.44 no.4
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    • pp.388-393
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    • 2017
  • We report an Agrobacterium-mediated transformation procedure optimized for 'Kyoho' that is a major table grapevine cultivar in Korea, and its transgenic plants with antifreeze protein gene of carrot (DcAFP). The full length of DcAFP coding region in accordance with the previous report was isolated from young leaves of carrot and recombined into a plant transformation vector. Ethylene inhibitors such as silver nitrate and aminoethoxyvinylglycin (AVG) supplemented in a co-cultivation medium distinctly increased frequency of shoot regeneration when explants were sub-cultured in a selection medium: particularly ten-fold higher in treatment with 0.1 mg/L AVG than one without ethylene inhibitor. Among various antibiotics and their concentrations, the combination of 150 mg/L cefotaxime plus 150 mg/L $Clavamox^{TM}$ was selected for elimination of Agrobacterium cells in addition to minimization of adverse effect on shoot regeneration, while 50 mg/L kanamycin monosulfate effectively suppressed regeneration of non-transgenic shoots. Applying the elucidated culture condition, we finally obtained a total of 5 transgenic 'Kyoho' plantlets with DcAFP, of which integration with the grapevine genome and transcription was confirmed by nucleic acid analyses.