• Journal of the Korea Society of Computer and Information
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• v.24 no.11
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• pp.11-19
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• 2019

Recently, hybrid CDN/P2P video streaming architecture is specially designed and deployed to achieve the scalability of P2P networks and the desired low delay and high throughput of CDNs. In this paper, we propose a cooperative video streaming and active node buffer management technique in hybrid CDN/P2P architecture. The key idea of this streaming strategy is to minimize network latency such as jitter and packet loss and to maximize the QoS(quality of service) by effectively and efficiently utilizing the information sharing of file location in CDN's proxy server which is an end node located close to a user and P2P network. Through simulation, we show that the proposed cooperative video streaming and active node buffer management technique based on CDN and P2P network improves the performance of realtime video streaming compared to previous methods.

• Journal of Korea Port Economic Association
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• v.25 no.3
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• pp.321-338
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• 2009

This study looks at the reasons behind the termination of container transportation between Busan and Incheon in terms of costs structure, the division of profit, and the economic limitation faced in the domestic shipping market. The operation costs have been examined in relation to the components of logistic system of container shipping and the cost function has been estimated. The distribution proportion of operation revenue has been also investigated, considering the different components of logistics activities. In addition, the average revenue of container vessels of 144TEU and 215TEU has been calculated. Economic limitation can be analysed through the optimisation behaviour of shipping companies which tries to maximize profit or minimize loss. In conclusion, domestic short sea shipping can get the economy of scale only by transporting vessels' maximum capacity. It is also vulnerable to trucking market's fluctuation. Without the subsidy for operation, the liner in domestic short sea shipping will stop the service in order to minimize the loss.

• Journal of Convergence for Information Technology
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• v.9 no.12
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• pp.133-140
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• 2019

This study examines the reason of a staggering trade deficit on the Korean agro-food industry. To achieve the goal of the study, this study suggests the policy implication for enlargement a trade deficit with foreign exchange rate. Despite the majority of grain importer does realize that there is a huge affection for price volatility on the business result, they are more likely to take flat pricing through the physical market to avoid risk of price volatility with exchange rate. Also the analysis of external and internal environments around the Korean agro-food export & import are conducted, particularly with the analysis of trade volume and food price affecting the export & import. Results from a survey show that the common factor to the effective use of overseas agricultural and foreign currency futures trading for grain traders in Korea.

• Journal of the Korea Society of Computer and Information
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• v.13 no.5
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• pp.247-253
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• 2008

Web 2.0 and Semantic Web technology will be merged to be a next generation Web that leads presentation-oriented Web to data-centric Web. In the next generation Web. semantic processing. Web Platform, and data fusion are most important technology factors. Resolving the Link Rot is the one of the essential technologies to enable these features. The Link Rot causes not only simple annoyances to users but also more serious problems including data integrity. loss of knowledge. breach of service. and so forth. We have suggested a new XRI-based persistent Web link architecture to cure the Link Rot that has been considered as a deep-seated Problem of the Web. The Proposed architecture is based on the XRI suggested by OASIS and it is designed to support a persistent link by using URL rewriting. Since the architecture is designed as a server-side technology, it is superior to existing research especially in Interoperability. Transparency and Adoptability. In addition to this, the architecture provides a metadata identification to be used fer context-aware link resolution.

• Journal of the Korea Society of Computer and Information
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• v.18 no.8
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• pp.53-64
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• 2013

The existing research on the QoS of the Streaming video system(SVS) adjust the video stream being sent from the network perspective, the focus is to prevent data loss and delay. The other hand, changing the quality of the video stream will not receive the guaranteed QoS from the perspective of the users who want uniform quality. In order to solve these problems, this paper applied to ensure that the benefits in the amount of bits per frame occurs Encoder CBR streaming video is kept constant and uniform picture quality advantages of VBR streaming video VBR to CBR Encoder and CBR to VBR Decoder, Video was designed to control the playback stream for And to ensure a uniform quality of the user based on the design and implementation of uniform quality guaranteed SVS. PSNR evaluated for several characteristics of the sample video to demonstrate the superiority of the SVS ensure uniform quality, the proposed Performance evaluation of the SVS ensure uniform quality CBW the ABR from 100% to ensure uniform image quality from 85% to environmental excellence is proved.

• Food Science and Preservation
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• v.17 no.5
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• pp.631-636
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• 2010

This study investigated the quality changes of cookie prepared with various concentrations of rice bran powder. Cookie were prepared by addition of 0, 5, 10, 20, and 30 powder to the flour of basic formulation. The specific gravity of cookie decreased with rising powder concentration. The volume and weight and specific volume increased with rising powder concentration. The moisture of cookie decreased with increasing powder concentration. With rising powder concentration, the a value of cookie increased but the L and b values decreased. The texture, hardness, cohesiveness, springness, gumminess, and chewiness of cookie decreased with rising powder concentration. The result of sensory evaluation when compared to cookie with 5% rice bran powder was superior in taste, flavor, and overall preference.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.119-125
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• 2021

As the electricity grid systems has been intelligent with the development of ICT technology, power consumption information of users connected to the grid is available to acquired and analyzed for the power utilities. In this paper, the energy theft problem is solved by feature selection methods, which is emerging as the main cause of economic loss in smart grid. The data preprocessing steps of the proposed system consists of five steps. In the feature selection step, features are selected using analysis of variance and mutual information (MI) based method, which are filtering-based feature selection methods. According to the simulation results, the performance of support vector machine classifier is higher than the case of using all the input features of the input data for the case of the MI based feature selection method.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.6
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• pp.1235-1242
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• 2018

When the wind speed changes rapidly, the wind turbine is stopped for the safety of the power system and the mechanical system. At that moment, the wind turbine gearbox is damaged and broken due to the contact load of the gearbox. In addition, the problems such as increasing frictional heat and deteriorate of the brake occur, because the power of the blades is transmitted directly to the brakes. This paper proposes a hybrid magnetic gear shape that solves the problem caused by the contact of the mechanical gear, which is the power transmission device of the wind power generation system, and the power cutoff system. The shape of the hybrid magnetic gearsuitable for the wind power generation system is derived through the torque and loss analysis according to the shape of the hybrid magnetic gear by using the two dimensional finite analysis method.

• Journal of IKEEE
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• v.23 no.3
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• pp.762-767
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• 2019

The plane-wave shielding effectiveness is typically measured for horizontal and vertical polarizations using a linearly polarized antenna. However, this typical measurement method results in big evaluation fees due to very long measurement time as well as huge idle space for maintenance, these problems is more severe especially in large shielded enclosures such as EMP protection facilities to be built in indoor buildings and underground. This paper describes the design and fabrication process and results of a planar log-spiral antenna applicable to the evaluation of the electromagnetic shielding effectiveness of a large EMP protection facility. Since the proposed antenna has a circular polarization, there is no need to separately measure the horizontal and vertical polarizations. Therefore, the measurement time can be shortened by more than 1/2, and further, its small volume with a planar structure can reduce greatly idle space required for the maintenance.

• The Journal of the Convergence on Culture Technology
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• v.5 no.2
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• pp.13-21
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• 2019

The purpose of this study was to identify the factors affecting life satisfaction in patients with alcohol use disorder. Participants were recruited at outpatient treatment facilities in two cites. Data were collected from October 1 to December 30, 2016, using self-report questionnaires. Abstinence self-efficacy, family support, and life satisfaction were investigated. 152 patients with alcohol use disorder participated in this study. Mean score for life satisfaction was 3.24. Life satisfaction had a positive correlation with abstinence self-efficacy and family support. Factors affecting life satisfaction in these men were abstinence self-efficacy. Findings indicate that abstinence self-efficacy and perceived mental health satisfaction are important variables influencing life satisfaction in patients with alcohol use disorder. Development and provision of intervention programs to increase abstinence self-efficacy and perceived mental health satisfaction will help to increase life satisfaction in patients with alcohol use disorder.