• Journal of Chest Surgery
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• 제47권4호
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• pp.389-393
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• 2014

Retroesophageal aortic arch, in which the aortic arch crosses the midline behind the esophagus to the contralateral side, is a rare form of vascular anomaly. The complete form may cause symptoms by compressing the esophagus or the trachea and need a surgical intervention. We report a rare case of a hypoplastic left heart syndrome variant with the left retroesophageal circumflex aortic arch in which the left aortic arch, retroesophageal circumflex aorta, and the right descending aorta with the aberrant right subclavian artery encircle the esophagus completely, thus causing central bronchial compression. Bilateral pulmonary artery banding and subsequent modified Norwood procedure with extensive mobilization and creation of the neo-aorta were performed. As a result of the successful translocation of the aorta, the airway compression was relieved. The patient underwent the second-stage operation and is doing well currently.

• 무역상무연구
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• 제60권
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• pp.213-234
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• 2013

e-Trade 3.0 era which means the expansion of seamless e-Trade process into global business has been come. e-Trade is in the evolution stage with the reflection of time changes and IT development. Furthermore e-Trade marketing method of SMEs has been generalized. However, SMEs have not utilized e-Trade marketing very actively even if it has much benefits in exploring overseas marketing. In this regard this paper has cautiously suggested the strategic using plan of e-Marketplace and SNS along with policy improvement in order to promote extensive diffusion of e-Trade marketing. First of all, a comprehensive evaluation system has to be developed for the assessment of overseas marketing program and provide organized guideline including SMEs support system. Also e-Marketplace operation company is necessary to invent management system for supervising and detecting risk factors of participating firms and business model to share information which each e-Marketplace possesses through mutual connection. Finally, the effective supports such as short-term education and acting operation of initial account to use SNS strategically are needed and continuous contents development to adopt SNS is absolute.

• Journal of Computing Science and Engineering
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• 제8권4호
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• pp.207-214
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• 2014

In pedestrian detection applications, one of the most popular frameworks that has received extensive attention in recent years is widely known as a 'Hough forest' (HF). To improve the accuracy of detection, this paper proposes a novel split function to exploit the statistical information of the training set stored in each node during the construction of the forest. The proposed split function makes the trees in the forest more robust to noise and illumination changes. Moreover, the errors of each stage in the training forest are minimized using a global loss function to support trees to track harder training samples. After having the forest trained, the standard HF detector follows up to search for and localize instances in the image. Experimental results showed that the detection performance of the proposed framework was improved significantly with respect to the standard HF and alternating decision forest (ADF) in some public datasets.

• 한국정보시스템학회지:정보시스템연구
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• 제26권1호
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• pp.75-91
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• 2017

Purpose Fintech has been recently drawing extensive attention all over the world as the innovative trend that will change the future of the global financial industry. However, fintech has been mostly focusing on the payment service in the embryonic stage in Korea. This paper will investigate the approach to increase the intention to use for those who do not use fintech at present. Design/methodology/approach This paper empirically analyzes the impact of innovation of users and the perceived ease-of-use and security on the intention to use through the perceived usefulness and confidence. The 255 survey responses were used to verify research hypotheses through covariate structural equation model. Findings According to the analysis results, it was found that innovation had a significant impact on the perceived usefulness, but had no significant impact on confidence. The perceived usefulness had a significant impact on perceived usefulness and confidence. Moreover, the perceived usefulness and confidence had a significant impact on the intention to use. Meanwhile, it was identified that the security perceived by those who do not use fintech had a negative impact on perceived usefulness, confidence, and intention to use related to fintech. Accordingly, fintech service providers need to determine an approach to help customers to have a positive perception on the security of fintech.

• 대한소아치과학회지
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• 제36권1호
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• pp.78-83
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• 2009

심한 치아 우식증, 외상, 발육성 결함으로 인한 근관치료 및 광범위한 수복이 필요한 소아, 청소년 시기의 유전치 및 영구 전치부 치료는 소아치과 의사에게 어려운 문제이다. 전치부에 사용되어온 기존의 수복 방법은 치질 손상이 광범위한 경우 유지력과 심미적 한계를 가지고 있으며, 특히 청소년기에 영구 전치를 수복할 경우 심미성과 유지력 뿐 아니라 성장 완료 후 영구 보철물 수복을 위한 전 준비 단계를 고려해야 한다. 본 증례는 소아, 청소년기의 광범위한 전치부 치관 손상에서 섬유 강화형 포스트를 이용하여 심미적 수복을 시도하였으며 양호한 결과를 얻을 수 있었다.

• Journal of Advanced Marine Engineering and Technology
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• 제10권3호
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• pp.94-106
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• 1986

Since the oil shock of '70s the engine makers have developed new types of diesel engine with low fuel consumption. There is an obvious tendency towards the use of poorer quality fuels, such as the residual oil from chemical processes of refinery. The shaft driving generators is also widely adopted on behalf of the auxiliary diesel engines, which are driving on the expensive diesel oil and have high fuel oil consumption rates, and some mania propulsion diesel engines are equipped with reduction gear systems to get better propulsive efficiency by slower propeller revolutions. The propulsion shafting system equipped with the shaft driving generator or the geared diesel engine shafting system has flexible couplings, and it requires extensive investigations of the torsional vibration and torque fluctuation in order to ensure the acceptable operation range in service. The characteristics of misfiring must be especially examined for the high viscosity fuels to be used. Both torsional vibration and fluctuating torque resulted from misfiring, should be examined for thier effects on the flexible coupling and propulsion shafting system. This paper is to investigate and solve the above mentioned problems which must be predicted on the design-stage of marine propulsion shafting system. A computer program is developed to calculate the indicated diagram, fluctating torque and torsional vibration for both normal and misfiring conditions.

• Journal of Welding and Joining
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• 제25권1호
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• pp.42-48
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• 2007

For high performance and structural stability, application of high strength steel has continuously increased. However, the change of the base metal gives rise to problems with the accuracy management of the welded structure. It is attributed to the martensite phase transformation of the high strength low alloy steel weldment. The purpose of this study is to establish the predictive equation of transverse shrinkage and residual stress for the HY-100 weldment. In order to do it, high speed quenching dilatometer tests were performed to define a coefficient of thermal expansion(CTE) at the heating and cooling stage of HY-100 with various cooling rates. Uncoupled thermal-mechanical finite element(FE) models with CTE were proposed to evaluate the effect of the martensite phase transformation on transverse shrinkage and residual stresses at the weldment. FEA results were verified by comparing with experimental results. Based on the results of extensive FEA and experiments, the predictive equation of transverse shrinkage and longitudinal shrinkage force at the HY-100 weldment were formulated as the function of welding heat input/in-plane rigidity and welding heat input respectively.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제30권6호
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• pp.540-544
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• 2004

The oral lesion of acquired syphilis - primary, secondary, and tertiary - is comparatively rare. Most of the time secondary syphilis manifests itself as a systemic disease with maculopapular eruptions of the skin, generalized lymphadenopathy, fever, and occasional eruptions on the mucous membranes. The lesions of the tertiary stage may occur anywhere in the body, including the oral cavity. Necrotizing faciitis of the head and neck is an uncommon, rapidly spreading soft tissue infection of polymicrobial origin characterized by extensive necrosis and gas formation in the subcutaneous tissue and superficial fascia. This is characterized by its fulminating, devastating, and rapid-progressing course. The mortality rate is high if it is not treated promptly and vigorously. Patients with an impaired immune system and those with small-vessel disease such as diabetes mellitus are more prone to develop this infection.

• 산업공학
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• 제16권2호
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• pp.125-139
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• 2003

This paper reports an empirical study on assessment of R&D best practices. The principles of quality management and their tools such as best practices or benchmarking have been so prevailing in the operational process that the R&D management recently consider extensive use of them for their innovation process. However, characteristics of the two processes may be different each other. Are the principles or the tools that were effective in the operational field still going to be effective in the innovative field? In order to answer the question, we statistically examine how R&D best practices contribute to the innovative performance. Upon literature review on technological innovation, we present a R&D process model whereby we set forth research hypotheses. Using data from 66 successful R&D efforts carried out among Korean firms mostly between 1999-2001, regression analyses reveal that best practices used in most stages throughout the R&D process are found not to significantly contribute to the innovative performance. Only those in technology strategy and prototyping stages are proven effective for technical and commercial performance respectively. Interestingly, efforts in a problem solving and improvement stage are counterproductive in the case of the innovation process. Discussions on our empirical observations are presented followed by some managerial implications.

• Structural Engineering and Mechanics
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• 제40권4호
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• pp.563-581
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• 2011

Many novel materials, developed in recent years, have obvious properties with different modulus of elasticity in tension and compression. The ratio of their tensile modulus to compressive modulus is as high as five times. Nowadays, it has become a new trend to study the mechanical properties of these bimodular materials. At the present stage, there are extensive studies related to the strength analysis of bimodular structures, but the investigation of the buckling stability problem of bimodular rods seems to cover new ground. In this article, a semi-analytical method is proposed to acquire the buckling critical load of bimodular slender rod. By introducing non-dimensional parameters, the position of neutral axis of the bimodular rod in the critical state can be determined. Then by combining the phased integration method, the deflection differential equation of bimodular pin-ended slender rod is deduced. In addition, the buckling critical load is obtained by solving this equation. An example, which is conducted by comparing the calculation results between the three of the methods including the laboratory tests, numerical simulation method and the method we developed here, shows that the method proposed in the present work is reliable to use. Furthermore, the influence of bimodular characteristics on the stability is discussed and analyzed.