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A Study on a Visual Sensor System for Weld Seam Tracking in Robotic GMA Welding (GMA 용접로봇용 용접선 시각 추적 시스템에 관한 연구)

  • 김동호;김재웅
    • Journal of Welding and Joining
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    • v.19 no.2
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    • pp.208-214
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    • 2001
  • In this study, we constructed a visual sensor system for weld seam tracking in real time in GMA welding. A sensor part consists of a CCD camera, a band-pass filter, a diode laser system with a cylindrical lens, and a vision board for inter frame process. We used a commercialized robot system which includes a GMA welding machine. To extract the weld seam we used a inter frame process in vision board from that we could remove the noise due to the spatters and fume in the image. Since the image was very reasonable by using the inter frame p개cess, we could use the simplest way to extract the weld seam from the image, such as first differential and central difference method. Also we used a moving average method to the successive position data or weld seam for reducing the data fluctuation. In experiment the developed robot system with visual sensor could be able to track a most popular weld seam. such as a fillet-joint, a V-groove, and a lap-joint of which weld seam include planar and height directional variation.

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Failure Studies on the Wear Scars of an Automotive Tire (차량용 타이어의 마멸손상에 관한 고장사례 연구)

  • Lee, II-Kwon;Kim, Chung-Kyun
    • Tribology and Lubricants
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    • v.23 no.5
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    • pp.228-233
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    • 2007
  • This paper presents the case studies on the friction related wears of an automotive tire, which is strongly connected to the safety and comfort of a driver during a running of a car. Wear scars of a tire tread are affected by various causes such as an air pressure, a wheel alignment, a driving speed, road conditions, starting and braking habits of a driver. The data were collected from used tires for a replacement at the car service center. Most of the wear problems came from the improper repair and adjustment of revolving components, which cause an unbalanced wear of a tread part of a tire. Thus, the regular checking of a tire radically reduces the wear scars of a tire and may increase a driving safety and a fuel economy of a car and a wear life of a tire.

A Study on Dynamic Inference for a Knowlege-Based System iwht Fuzzy Production Rules

  • Song, Soo-Sup
    • Journal of the military operations research society of Korea
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    • v.26 no.2
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    • pp.55-74
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    • 2000
  • A knowledge-based with production rules is a representation of static knowledge of an expert. On the other hand, a real system such as the stock market is dynamic in nature. Therefore we need a method to reflect the dynamic nature of a system when we make inferences with a knowledge-based system. This paper suggests a strategy of dynamic inference that can be used to take into account the dynamic behavior of decision-making with the knowledge-based system consisted of fuzzy production rules. A degree of match(DM) between actual input information and a condition of a rule is represented by a value [0,1]. Weights of relative importance of attributes in a rule are obtained by the AHP(Analytic Hierarchy Process) method. Then these weights are applied as exponents for the DM, and the DMs in a rule are combined, with the Min operator, into a single DM for the rule. In this way, the importance of attributes of a rule, which can be changed from time to time, can be reflected in an inference with fuzzy production systems.

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A 12-Bit 2nd-order Noise-Shaping D/A Converter (12-Bit 2차 Noise-Shaping D/A 변환기)

  • 김대정;김성준;박재진;정덕균;김원찬
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.12
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    • pp.98-107
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    • 1993
  • This paper describes a design of a multi-bit oversampling noise-shaping D/A converter which achieves a resolution of 12 bits using oversampling technique. In the architecture the essential block which determines the whole accuracy is the analog internal D/A converter, and the designed charge-integration internal D/A converter adopts a differential structure in order to minimize the reduction of the resolution due to process variation. As the proposed circuit is driven by signal clocks which contains the information of the data variation from the noise-shaping coder, it minimizes the disadvantage of a charge-integration circuit in the time axis. In order to verify the circuit, it was integrated with the active area of 950$\times$650${\mu}m^{2}$ in a double metal 1.5-$\mu$m CMOS process, and testified that it can achieve a S/N ratio of 75 dB and a S/(N+D) ratio of 60 dB for the signal bandwidth of 9.6 kHz by the measurement with a spectrum analyzer.

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Dioxygen Transfer from 4a-Hydroperoxyflavin Anion to Isomeric Aminophenolates

  • Sam-Rok Keum;Ki-Bong Lee;Thomas C. Bruice
    • Bulletin of the Korean Chemical Society
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    • v.11 no.2
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    • pp.95-99
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    • 1990
  • The dioxygen transfer reaction from $N^5$-ethyl-4a-hydroperoxy-3-methyllumiflavin anion (4a-FlEtOO-) has been extended to isomeric aminophenol systems (1a-4a). O-aminophenol (o-AP, 1a & 2a) and p-aminophenol(p-AP, 3a & 4a) were turned out to be good substrates, whereas m-aminophenol(m-AP, 5a) was not. This is due to the charge location which is not on the carbon bearing the amino group. o-AO's react with 4a-FlEtOO- to give isophenoxazine derivatives (6 & 7) and with p-AP's to produce p-benzoquinone derivatives (8 & 9). The partition coefficients $(k_2/k_3)$ of 1a & 2a were $4.84{\times}10^{-4}\;&\;1.66{\times}10^{-5}M$, respectively and those of methylated aminophenolates, 2a & 4a were 4-10 times greater than nonmethylated substrates, 1a & 3a.

A Study on the Elasticity Disuniformity for Catenary using by Beam Model (빔 모델을 이용한 전차선 불균일율에 관한 연구)

  • 권삼영;이기원;조용현;정흥채
    • Proceedings of the KSR Conference
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    • 1999.11a
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    • pp.209-217
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    • 1999
  • A catenary system should be designed to be an uniform elasticity over a span in order to maintain the lowest possible loss of contact between a pantograph and a contact wire. A elasticity disuniformity of a catenary can be regarded as a important design factor used for predicting the current collection performance for a catenary. There are a couple of formulas to calculate elasticity disuniformity of a catenary according to the literature survey, The effectiveness of these formulas is reviewed by performing catenary elasticity and loss of contact analysis for 5 different configurations of catenary systems using a beam element based FEM program, KRRI developed program, and the loss of contact by GASENDO, RTRI developed program, respective]y. The results reveals that these formulas are not suitable to predict the current collection performance for a catenary. Therefore, a new formula based on the standard deviation of the elasticity over a span is proposed in this study. The analysis results show that the new formula for an elasticity disuniformity of a catenary is very effective in predicting the current collection performance for a catenary.

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[$(3aR^*,6aS^*)$-6a-Hydroxy-Asymmetric Synthesis of cyclopenta[b]pyrrole-3a-carboxylate and Determination of Its Stereostructure via NMR Spectrum ($(3aR^*,6aS^*)$-6a-Hydroxy-cyclopenta[b]pyrrole-3a-carboxylate의 부제합성 및 NMR 스텍트럼을 통한 입체구조의 결정)

  • Kwon, Soon-Kyoung;Park, Myoung-Suk;Seo, Won-Jun
    • YAKHAK HOEJI
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    • v.38 no.5
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    • pp.544-554
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    • 1994
  • Pyrrolidine-2,3-dione derivative A was synthesized from oxalylation of chiral enamine Ba. The stereostructure of its major diastereomer $(A_{maj})$ was determined as octahydro-2,3-dioxo-6aS-hyd roxy-1-(1S-methoxycarbonyl-2-phenylethyl)-cyclopenta[b]pyrrole-3aR-carboxylic acid ethyl ester Aa by means of NMR spectrum. This result implied that the asymmetric carbon-carbon bond forming reaction occurred preferentially at the ${\beta}-face$ of Ba.

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The Effect of Marketing Mix elements on brand Equity (마케팅 믹스 요소가 브랜드 자산에 미치는 영향에 관한 연구)

  • Ryu, Jang-Mu
    • Journal of Industrial Convergence
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    • v.1 no.1
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    • pp.41-70
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    • 2003
  • Many researches on brand equity have been focused in definition about it, factors of it, and the process of formation. Most of them have been used by voluntary production category, as is durable goods or nondurable goods. But this study, using the model is developed by Foote, Cone & Be1ding(FCB) Company, classified four fields, high-low involvement, rationality(rational or sensitive) involvement. The selected goods is a sensitive high involvement(casual wear). This study investigate the effects of brand equity and search the influences of brand equity formation according to factors of marketing mix. To this goals, this study kept a literature survey and a demonstrative research. In literature survey, there are several definitions of brand and brand equity. The research model is derived from selected factors of marketing mix and former study. This study used the regression analysis to verify effects from brand equity through the selected marketing mix. The research data is collected from the capital area. The focus of this study is effects of brand equity according to marketing mix. The followings are results and suggestions of this study. First, in the price factors, the affirmative effects are revealed the perceived quality and the brand awareness in a rational high involvement goods, the perceived quality and the brand associations in a sensitive high involvement goods, all factors of brand equity in a rational low involvement goods, and the perceived quality in a sensitive low involvement goods. As summary, the important characteristics is the price factors to consumers, and consumers recognize that a high price means a high quality. Second, in the store image factors, the affirmative effects are revealed all brand equity factors in a rational high involvement and a sensitive high-low involvement. A good store image incites more interest, contact, and visit from potential consumer. And such store offers more consumer satisfaction, simulates more active and positive conversation to consumers. Third, in advertising spending factors, the affirmative effects are revealed the brand awareness and associations in a rational high involvement and a sensitive high involvement, all brand equity factors in a rational low involvement and a sensitive low involvement. An advertisement increases not only a brand awareness but also strong brand associations. Forth, in price promotion factors, the affirmative effects are revealed the brand associations in a rational high involvement, the negative effects are revealed all brand equity in sensitive high involvement. According the result about the effects of brand royalty through the brand equity factors, a perceived quality and brand associations have positive effects to brand royalty in all factors. Consumers choice a deep perceived quality than other competitive brand. So, brand equity will increase according to a qualitative grade of a perceived brand by consumers. Brand associations represent a quality and a degree of involvement. In conclusion, brand associations and equity have a positive relation each other. According to the analysis results about a brand royalty of selected marketing mix factors, the affirmative effects are revealed the store image and price promotion factors in a rational high involvement, the price and store image in a sensitive high involvement, and the price and advertising spending in a rational low involvement. The results about the affect of selected marketing mix factors according to brand equity, are the perceived quality in a high involvement, and all brand equity factors in a low involvement. The affirmative effects about a store image are revealed all equity factors in high-low involvement. In advertising spending factors, the affirmative effects are revealed the brand awareness and associations in a high involvement goods, and the perceived quality and the brand awareness in a low involvement goods. In price promotion factors, the affirmative effects are revealed the brand awareness in a low involvement goods, and the negative effects are revealed the brand awareness in a high involvement goods. According to a degree of involvement, the results of a brand royalty through a brand equity factors are following. The affirmative effects are revealed the perceived quality and the brand royalty in a high involvement goods, and the brand awareness are revealed a negative effect. The affirmative effects are revealed the perceived Quality and the brand associations in a low involvement goods. So, in a high involvement goods, the brand royalty is built by strong brand associations, but, in a low involvement goods, the brand royalty is built also by a perceived Quality and a brand awareness. This study have some concept of limitation. So, this study presents a future direction of research. First, a future study has to have more deep analysis for this study analyzed through a limited marketing mix factors. Second, a future research has to get mutual effects about brand equity of marketing mix factors for this study has an individual marketing decision factors. Third, for the future, a brand equity needs a research about a several goods such as services, profit or nonprofit, industrial products, culture, and so on. Forth, the research have to diversify a various data for population.

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Phylogenetic relationships of Armillaria spp. on the basis of ITS region sequences (rDNA의 ITS 부위 염기서열 분석에 의한 Armillaria 속 수집 균주의 유전적인 유연관계 분석)

  • Oh, Jin-A;Lee, Chan-Jung;Cheong, Jong-Chun;Yoo, Young-Bok
    • Journal of Mushroom
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    • v.10 no.3
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    • pp.143-149
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    • 2012
  • Armillaria spp are well known as a symbiotic fungus with Gastrodia elata. This study was carried out to identify and analyze the genetic relationships among 83 strains of Armillaria spp.. The amplified internal transcribed spacer(ITS) region of the rDNA was about 500~750 bp long and identified by 9 strains; A. mellea, A. tabescens, A. ostoyae, A. gallica, A. novae-zenlandia, A. cepistipes, A. nabsnona, A. gemina, A. sinapina. Sequence analysis showed that 52% of strains were different with original identification. A. gallica, A. cepistipes and A. gemina were so close phylogenetic relationship, that was difficult to classify using ITS region. In A. gallica, 12 strains including ASI10104 were showed a close phylogenetic relationship with A. gallica, A. cepistipes and A. gemina. ASI10017 and ASI10114 were classified as the A. sinapina group, ASI10045 was the A. borealis group, ASI10002 and ASI10025 were the A. ostoyae group. So more studies need for more accurate identification and determine the phylogenetic relationships of Armillaria spp.

The Dopamine $D_2$ Receptor Locus as a Modifying Gene in Korean Schizophrenia, Alcoholism and Drug Addiction (정신분열증, 알코올중독, 약물중독에서 도파민 $D_2$ 수용체 유전자의 조절유전자(modifying gene)로서의 역할 - 충동적.강박적.탐닉적 행동을 나타내는 정신질환들에서 도파민 $D_2$ 수용체의 조절유전자로서의 역할 -)

  • Jung, Hyun-Mo;Lee, Hong-Seock;Chang, Dong-Won;Lee, Min-Soo
    • Korean Journal of Biological Psychiatry
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    • v.4 no.2
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    • pp.225-233
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    • 1997
  • The authors attempted to examine the allelic association between the A1 allele of Dopamine $D_2$ receptor and schizophrenia, alcoholism, drug addiction in Koreans. Schizophrenic patients(n=31), alcoholism(n=65), drug addiction(n=18) and controls(n=52) were examined by case-control study for distribution of the TaqI polymorphism of the dopamine $D_2$ receptor gene in Korean population to minimize the effect of racial differencies in gene frequencies. In schizophrenics, the numbers of schizophrenics with A1A1, A1A2, A2A2 were 9(29.0%), 15(48.4%) and 7(22.6%) respectively and in alcoholics with A1A1, A1A2, A2A2 were 14(21.5%), 36(55.4%) and 15(23.1%) respectively and in drug addiction with A1A1, A1A2, A2A2 were 2(11.1%), 10(55.6%) and 6(33.3%) respectively and in controls with A1A1, A1A2, A2A2 were 4(7.6%), 24(46.2%) and 24(46.2%) respectively. The prevalence of the A1 allele in schizophrenics, alcoholics, drug addiction and controls were 77%, 76.9%, 67% and 53.8% respectively. And the frequency of the A1 allele in schizophrenics, alcoholics, drug addiction and controls were 0.53, 0.49 0.39 and 0.31 respectively. There was significant difference in the frequency of the A1 allele between schizophrenics, alcoholics and controls. We also classified our alcoholic population. For classification by severity, we used the median MAST score 30 in our samples. There was also significant difference in the frequency of the A1 allele between less severe group(0.42) and more severe group(0.57). This data suggest that the A1 allele is associated with schizophrenia and alcoholism in Koreans. Furthermore the prevalence of the A1 allele increassed in more severely affected alcoholics. The authors conclude that our data support an allelic association between the A1 allele at dopamine $D_2$ receptor and schizophrenia, alcoholism. These results suggest the A1 allele of the $DRD_2$ gene is associated with a number of behavior disorders in which it may act as a modifying gene rather than as the primary etiological agent.

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