• Journal of Internet Computing and Services
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• v.11 no.5
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• pp.119-126
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• 2010

In this paper, we analyze the robustness of transformed-key asymmetric watermarking system and show its improvement by proposing a new detection method. Based on the assumption that the transformed-key asymmetric watermarking system is under the threat of subtraction attack, we first propose the criterion for the detection performance of the watermarking system and analyze the optimum condition on the system. Next, a new detection method is proposed to improve the detection performance of the system based on the criterion. The proposed improvement makes the system robust to not only subtraction attack but also Wu's attack.

• Journal of Korea Port Economic Association
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• v.29 no.2
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• pp.63-79
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• 2013

The fundamental endeavor of this study is to investigate the asymmetric relationship between bunker price and Baltic Dry-bulk Index (hereafter BDI). Previous investigations employ linear form based analysis between oil price and BDI but we develop nonlinear and asymmetric cointegration method, which is properly able to capture the decreasing and increasing periods differently. The empirical results show there is no relationships in linear model (e.g. Engle and Granger's methods). On the contrary, our estimate reveals there is significant long-run relationship with asymmetric framework, which implies the necessity of nonlinear and asymmetric consideration to the bunker price analysis.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.335-338
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• 2007

In the case of an antiaircraft missile, high angle of attack flight capability is required to get the agile maneuverability in a supersonic flow. Even through a symmetric slender body does not have side slip, asymmetric vortex is generated at high angle of attack conditions. This asymmetric vortex produces unnecessary side force and yawing moment; hence, these effects deteriorate directional stability. In this study, the numerical analysis of asymmetric vortices around the slender body was conducted at high angle of attack supersonic flow. In order to simulate the vortices, a bump is installed on the nose of the slender body. As a result of the numerical analysis, the asymmetric vortices around the slender body could be simulated.

• Journal of the Society of Naval Architects of Korea
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• v.35 no.1
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• pp.24-31
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• 1998

Unsteady propeller blade forces arising from shaft inclination have been found to be an important contribution tn total blade forces. The position of the wake relative to a blade oscillates with the first blade frequency, thus giving rise to unsteady blade forces which is significant relative to the forces produced directly by flow inclination. In order to find a wake geometry due to shaft inclination, a non-axisymmetric wake model is developed and applied to a specific case, which has experimental values. Predicted cavity shapes and unsteady forces acting on the blades of an inclined shaft propeller are compared to those predicted by other numerical methods, as well as those measured in experiments.

• International Area Studies Review
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• v.15 no.1
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• pp.59-86
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• 2011

This paper examines a country's strategic optimal tariff policy against a foreign firm with market power. That is, the purpose of the paper is, under asymmetric information, to reexamine the problem of optimal tariff policy against a foreign monopolist from another country's welfare standpoint. This is to extend the analysis of Brander and Spencer(1984) which is both analytic and elaborate. The incentive compatible tariff schedule is derived, and then policy implications are investigated. The main result is that, under incomplete information, the optimal tariff is elevated above its full-information counterpart in order to capture foreign rents. Moreover, it suggests that trade policies motivated by rent extraction are unlikely to be robust to the introduction of incomplete information. This research complements an existing literature on the strategic trade policy in terms of asymmetric information.

• The Korean Journal of Financial Management
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• v.25 no.1
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• pp.109-140
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• 2008

The primary objective of this paper investigates whether asymmetric volatility phenomenon is caused by differences of opinion among investors and analyses information availability has an effect on asymmetric volatility. The empirical test period covers recent 6 years from January 4, 2000 to December 29, 2005. Five portfolios have been formed according to information availability(volume and market value). For the purpose of this study, We use TGARCH model, TGARCH-M model and adjusted model which include trading volume as a proxy differences of opinion among investors. The results are summarized as follows ; First, adjusted model analysis shows that asymmetric volatility phenomenon is disappeared or asymmetric coefficient and ratio is decreased than basis model. Second, portfolio analysis shows that the higher volume and market value, the more prominent asymmetric volatility phenomenon. And adjusted model analysis shows the higher volume and market value, the more decrease asymmetric ratio. Over all, assertion that differences of opinion among investors has caused asymmetric volatility phenomenon is regarded as reasonable. And, We see that information availability have great effect on asymmetric volatility phenomenon. We think that theses results can also occur opinion adjustment of optimistic investors. Namely, asymmetric volatility phenomenon can occur difference of information authenticity.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.1
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• pp.77-87
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• 2010

Skeletodental asymmetries are common and asymmetric orthodontic treatments are very difficult to correct successfully. The cause of asymmetries can be the skeletal asymmetry, dental, or functional, or combinations of these causes. Skeletodental asymmetries can be the result of congenital factors, such as hemifacial microsomia and environmental factors, such as trauma. Optimal treatment outcome of the severe facial asymmetry requires the orthognathic surgery. Mild asymmetry problem can be treated by only orthodontic treatment. The orthodontic treatment of asymmetry is usually difficult. Facial asymmetry orthodontic treatment are primarily based on proper diagnosis and careful treatment planning. Side effects of asymmetric elastic to treat midline discrepancies are canted occlusal plane, tipped incisors and unesthetic results. In the management of dental arch asymmetries, the clinician should select the appropriate force system and the appliance design necessary to address the asymmetry while minimizing undesirable side effects. This report presents treatment strategies for the treatment of skeletodental asymmetry. In this case report, the clinical case with midline discrepancies treated by optimal mechanics is described. Through diagnosis and strategic treatment mechanics can obtain proper midline correction with minimal side effects.

• The Journal of the Korea Contents Association
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• v.19 no.5
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• pp.280-286
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• 2019

This study first examines whether the matching principle reduces information asymmetry and verifies the effect on earnings sustainability and information asymmetry. In the presence of information asymmetry between managers and information users, managers can reduce information asymmetry by increasing the quality of earnings. Information asymmetry is measured by the financial analysts' earnings forecast variance. When we look at the results of previous studies, verify whether information asymmetry decreases as the response to the revenue cost increases and whether negative relationship between profit persistence and information asymmetry appears when the response to the revenue cost is high. As a result, firms with high revenue cost response showed a decrease in information asymmetry. The persistence of the earningss from the high earnings-cost response shows that the analysts' earnings forecast dispersion decreases. This means that the better the response to the revenue cost, the better the quality of the earnings and the less the information risk about the uncertainty of the enterprise. This study is different from the previous studies in that it analyzed whether the persistence of the earnings that responded to the high revenue cost reduces the information asymmetry. The results of this study suggest that managers can reduce the information asymmetry by carrying out appropriate revenue - cost responses, which provides important implications for stakeholders who use accounting earnings information.

• Iberoamérica
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• v.21 no.1
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• pp.57-105
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• 2019

This paper deals with the regional asymmetries of MERCOSUR and regional development cooperation for its solution. Through the formation of a common market, the countries of Southern Cone expected to grow evenly. However MERCOSUR had structural asymmetry from the beginning and exposed policy asymmetry over time. It is basically due to the overwhelming influences of Brazil on MERCOSUR. With regard to asymmetries, Paraguay calls for special and differential treatment. Uruguay wants equitable application of market liberalization. Argentine emphasizes production integration based on the development of value chains. In the issue of asymmetries, while Paraguay, Uruguay and Argentine act as petitioners, Brazil is capable of selecting the initiatives. Under these circumstances MERCOSUR has established FOCEM as regional redistribution mechanism. FOCEM has achieved some results as seen in Paraguay, but there are still problems such as financial limitations and lack of enforcement. In oder to activate the redistributive mechanism for regional integration and to coordinate the policies to resolve regional disparities, transnational governance is essential but all member countries are reluctant to it. To date, regional asymmetries or development gaps have persisted and disparities in individual countries remains a problem.

• Proceedings of the KWS Conference
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• 2004.05a
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• pp.109-111
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• 2004

아크 플라즈마의 온도 분포를 측정하는 방법으로 개발된 CCD 카메라를 이용한 온도 측정 방법을 비대칭 플라즈마의 온도 분포 측정에 적용하기 위해 비대칭 플라즈마의 데이터 변환에 이용 가능한 아벨 역산 방법을 개발하였다. 비대칭 플라즈마 중 V-groove 상의 아크는 타원형의 플라즈마로 볼 수가 있으므로 타원형의 단면을 가지는 플라즈마에 대해 온도 측정을 수행하고 그 결과로서 모재로 전달되는 아크의 열속(heat flux)의 분포를 예측 할 수 있었다.