• Journal of the Korean Society for Nondestructive Testing
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• v.27 no.4
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• pp.339-344
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• 2007

Safety of large scale cable in bridge is very important because it may cause the unwanted catastrophic failure. Although the proof load were considered at the design stage, its soundness must be monitored continuously because the cable may be broken out without warning by the variable external load. The cable tension of in-use structures has been mainly measured by the resonance method and its use has been limited because of relatively large measurement uncertainty. Recently a new magnetic method was developed and its reliability is known to be good for evaluating the cable tension. In this study a system which can deliver the calibrated load to the cable was developed and the measurement reliability of developed magnetic sensor according to the change of external load was analyzed quantitatively. The effect of magnetization frequency, bias magnetic field, and temperature on the sensor output was also evaluated.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.507-514
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• 1999

한국전력에서는 인천화력 4호기 수명연장의 일환으로 여자시스템 교체가 이루어졌다. 기존의 회전형 여자 시스템은 발전기축에 부여자기와 교류여자기가 부착되어 회전하는 형태로 과거 스위칭소자 용량의 한계를 극복하기 위하여 설계된 시스템으로 전력연구원에는 회전형 여자시스템을 새롭게 개발된 아날로그와 디지털의 하이브리드 제어기와 대용량 사이리스터 제어정류기를 가지고 잇는 정지형 이중화 여자시스템으로 교체하였다. 설비의 신뢰성을 높이기 위하여 정지형 여자시스템의 상태를 순시 감시하기 위한 데이터 취득 시스템이 설치 되었고 위상제어정류기는 운전시 1대가 고장이 발생하더라도 발전기의 전부하 능력을 유지하기 위하여 3대가 병렬로 운전되는 N+1 방식을 채택하였다. 시스템의 신뢰성 시험은 성능평가를 위한 시운전시에 검증되었으며 성공적으로 운전중에 있다.

• Journal of Industrial Convergence
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• v.13 no.3
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• pp.57-76
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• 2015

The purpose of this paper is to examine the moderate effects of self monitoring and the ways of thinking on the relationships and the moderate effects of brand credibility and brand attachment on the relationships between the negative information about a brand and the customer attitude holistic and analytic on the relationships between the negative information about a brand and customer attitude. To accomplish these purposes, this research divided negative information about a brand into corporate ability and corporate social responsibility. In addition, research also divided product type into functional product and symbolic product. participants are classified as having Low or High self monitoring. and the ways of thinking divided into holistic and analytic on the relationships between the negative information about a brand and customer attitude. The following are the summary of hypothesis test: (1)the consumers with low(high) level of self monitering are more likely to reveal high level of preference for negative information of corporate ability. (2)the consumers with analytic(holistic) ways of thinking are more likely to reveal high level of preference for negative information of corporate ability. (3)the consumers with low(high) level of self monitering are more likely to reveal high level of preference for functional product. (4)the consumers with analytic(holistic) ways of thinking aren't more likely to reveal high level of preference for functional(symbolic) product.

• The Korean Journal of Financial Studies
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• v.11 no.1
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• pp.61-99
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• 2005

신용평가제도는 오늘날 그 영향력이 강력해져 사실상 세계자본시장의 문지기역할을 하고 있다. 본 논문에서는 이와 같이 신용평가기관의 중요성과 영향력의 증대와 더불어 이들 평가기관의 활동에 대한 비판과 감시가 커지고 있는 이때에 아직 선진수준에 미치지 못하는 국내신용평가기관들의 현황과 평가체계를 살펴보고 선진국의 신용평가기관들과 비교해 봄으로써 앞으로 나아갈 방향을 모색해보고자 하였다. 국내 신용평가기관들의 현황을 살펴본 결과 신용평가절차에 있어서 기준이 경영상태, 성장성, 그리고 재무구조의 건전성에 있어야 함에도 불구하고 이러한 기본적인 요인들의 영향력은 미미한 반면, 비공개적이고 불투명하며 비경제적인 요인들이 중요한 비중을 차지하고 있었다. 이에 반하여 선진신용평가기관들의 분석결과는 그 신뢰도에 믿음을 가질 수 있고, 대내외적인 공신력을 인정받고 있으며, 평가과정이 매우 주관적이어서 그 내용을 모두 공개하지 않지만, 국내의 신용평가과정보다는 투명성을 인정받고 있다는 것도 사실이다. 따라서 국내신용평가기관들의 나아갈 바를 살펴보면 다음과 같다. 첫째, 비재무적 요인의 평가기준에 대한 인식의 재정립이 요구되고 있다. 장기적인 시각으로 비재무적 요인에 대한 평가기준과 방법에 대한 체계의 정립이 요구되며, 전문적이고 객관적이면서도 뚜렷한 평가기관의 주관이 있는 평가가 이루어져야 할 것이다. 둘째, 신용평가방법과 기준의 강화로 대외적인 공신력을 얻도록 해야 한다. 이를 위한 방안의 하나로 성장성, 수익성, 그리고 안정성 비율 모두를 반영할 수 있는 신용평가모형을 개발하고, 자기자본비율의 대폭적인 상승이나 현금흐름의 양호여부, 경제적 부가가치(EVA), 고정장기적합률의 이행기준의 설정 등에 대한 평가기준의 재정립이 강구되어야 할 것이다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.11
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• pp.2562-2568
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• 2015

This paper proposes a detection method for irregularity of ionospheric delay in network RTK (Real Time Kinematic) Environment. The linearity of network RTK correction provided to user can't be assured when a characteristic of temporal-spatial of ionospheric delay is rapidly changed due to geomagnetic storm or solar flare. Therefore, incorrect ambiguity can be resolved and positioning error can be increased. A detection method for irregularity of ionospheric delay is needed to provide reliable correction. In this paper, index to detect irregularity of ionospheric delay is calculated from dispersive corrections and occurrence of irregularity is judged by comparing index and thresholds.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.7
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• pp.922-934
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• 2013

This study investigates the motivations to purchase luxury brands by examining how individual characteristics (need for uniqueness, self-monitoring, and vanity) influence affective luxury brand attitudes and purchase intentions through two social function attitudes (self-expression attitude and self-presentation attitude) based on the functional theory of attitudes. On-line surveys were implemented and 314 consumers between the ages of 20 and 50 were recruited. Using SPSS 18.0 and AMOS 18.0, confirmatory factor analysis for measurements and structural equation modeling analysis for hypotheses testing were implemented. The results show that the need for uniqueness and self-monitoring by consumers have positive influences on self-expression and self-presentation attitudes toward luxury brands, respectively. The results indicate that the need by consumers for uniqueness motivates a self-expression attitude toward luxury brands and that the trait of self-monitoring motivates a self-presentation attitude toward luxury brands. Consumer vanity also positively influences both social function attitudes toward luxury brands. Self-expression and self-presentation attitudes toward luxury brands have positive influences on luxury brand purchase intentions through an affective attitude that facilitates a mediating role between two social function attitudes and the purchase intentions of consumers. This research contributes to a deeper understanding of the formation process of Korean consumers' purchase intentions for luxury brands and the literature on the role of related variables (need for uniqueness, self-monitoring, vanity, self-expression, self-presentation, affective attitude, and purchase intention). The findings provide a theoretical background to launch a cross-cultural study. The conclusion discusses the practical implications and limitations.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.2
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• pp.133-139
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• 2003

In order to extend the life time of building and civil infra-structure, nowadays, patch type fibrous composite materials are widely used. Repaired concrete columns and beams gain the stiffness and strength, but they lose toughness and show brittle failure. Usually, the cracks of concrete structures are visible with naked eyes and the status of the structure in the life cycle is estimated with visible inspection. After repairing of the structure, crack visibility is blocked by repaired carbon sheets. Therefore, structural monitoring after repairing is indispensible and self diagnosis method with optical fiber sensor is very useful. In this paper, peel-out effects is detected with optical fiber sensors and the strain difference between main structure and repaired carbon sheets when they separate each other.

• Journal of Astronomy and Space Sciences
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• v.26 no.4
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• pp.467-478
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• 2009

The super-geomagnetic storms called 2003 Halloween event globally occurred during the period of 29 through 31 which are the following days when the solar flares of X18 class exploded on 28 October 2003. The S4 index from GPS signal strength and the peak electron density ($NmF_2$) from GPS tomography method are analyzed according to the date. The occurrences of the cycle slip and scintillation in the GPS signals are 1,094 and 1,387 on 28 and 29 October, respectively and these values are higher than 604 and 897 on 30 and 31 October. These mean the ionospheric disturbances are not always generated by the period of geomagnetic storm. Therefore, GPS S4 index is useful to monitor the ionospheric disturbances. Behaviors of ionospheric electron density estimated from GPS tomography method are analyzed with the date. At UT = 18 hr, the maximum $NmF_2$ is shown on 28 October. It agrees with $NmF_2$ variation measured from Anyang ionosonde, and the GPS signal are better condition on 30 and 31 October than 28 October. In conclusion, GPS signal condition is relation with geomagnetic activities, and depend upon the variation of the electron density. We will study the long-term data to examine the relationship between the GPS signal quality and the electron density as the further works.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6420-6426
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• 2013

The indoor areas for the commercial use of automatic monitoring systems of mobile robot localization improves the cognitive abilities and the needs of the environment with this emerging and existing mobile robot localization, and object recognition methods commonly around its great sensor are leveraged. On the other hand, there is a difficulty with a problem-solving self-location estimation in indoor mobile robots using only the sensors of the robot. Therefore, in this paper, a self-position estimation method for an enhanced and effective mobile robot is proposed using a marker and CCTV video that is already installed in the building. In particular, after recognizing a square mobile robot and the object from the input image, and the vertices were confirmed, the feature points of the marker were found, and marker recognition was then performed. First, a self-position estimation of the mobile robot was performed according to the relationship of the image marker and a coordinate transformation was performed. In particular, the estimation was converted to an absolute coordinate value based on CCTV information, such as robots and obstacles. The study results can be used to make a convenient self-position estimation of the robot in the indoor areas to verify the self-position estimation method of the mobile robot. In addition, experimental operation was performed based on the actual robot system.

• Journal of the Korean Orthopaedic Association
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• v.55 no.3
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• pp.261-265
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• 2020

A lumbar juxtafacet cyst is a rare disease that causes low back pain, radiculopathy and neurological claudication by compressing the nerve roots. A 34-year-old male complained of severe low back pain and radicular pain in the right lower extremity. Magnetic resonance images revealed a cyst at the lateral recess of the spinal canal between the L3-4 disc and posterior facet joint that extended to the L4 body level. Under the guidance of an image intensifier, needle aspiration of the cyst was performed, which extracted 1.5 ml of serous, yellowish colored fluid. After the aspiration, the symptoms subsided dramatically. The follow-up magnetic resonance images showed no recurrence of the cyst. To the best of the author's knowledge, there are no reports of lumbar juxtafacet cyst treated with needle aspiration in Korea. This case is reported with a review of the relevant literature.