• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.9
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• pp.4287-4306
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• 2016

Network resilience provides an effective way to overcome the problem of network failure and is crucial to Internet protocol (IP) network management. As one of the main challenges in network resilience, recovering from link failure is important to maintain the constancy of packets being transmitted. However, existing failure recovery approaches do not handle the traffic engineering problem (e.g., tuning the routing-protocol parameters to optimize the rerouting traffic flow), which may cause serious congestions. Moreover, as the lack of QoS (quality of service) restrictions may lead to invalid rerouting traffic, the QoS requirements (e.g., bandwidth and delay) should also be taken into account when recovering the failed links. In this paper, we first develop a probabilistically correlated failure model that can accurately reflect the correlation between link failures, with which we can choose reliable backup paths (BPs). Then we construct a mathematical model for the failure recovery problem, which takes maximum rerouting traffic as the optimizing objective and the QoS requirements as the constraints. Moreover, we propose a heuristic algorithm for link failure recovery, which adopts the improved k shortest path algorithm to splice the single BP and supplies more protection resources for the links with higher priority. We also prove the correctness of the proposed algorithm. Moreover, the time and space complexity are also analyzed. Simulation results under NS2 show that the proposed algorithm improves the link failure recovery rate and increases the QoS satisfaction rate significantly.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.44 no.3
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• pp.229-238
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• 2008

This paper describes on the consolidation of AIS and ARPA radar positions by comparing the AIS and ARPA radar information for the tracked ship targets using a PC-based ECDIS in Busan harbor, Korea. The information of AIS and ARPA radar target was acquired independently, and the tracking parameters such as ship's position, COG, SOG, gyro heading, rate of turn, CPA, TCPA, ship s name and MMSI etc. were displayed automatically on the chart of a PC-based ECDIS with radar overlay and ARPA tracking. The ARPA tracking information obtained from the observed radar images of the target ship was compared with the AIS information received from the same vessel to investigate the difference in the position and movement behavior between AIS and ARPA tracked target ships. For the ARPA radar and AIS targets to be consolidated, the differences in range, speed, course, bearing and distance between their targets were estimated to obtain a clear standards for the consolidation of ARPA radar and AIS targets. The average differences between their ranges, their speeds and their courses were 2.06% of the average range, -0.11 knots with the averaged SOG of 11.62 knots, and $0.02^{\circ}$ with the averaged COG of $37.2^{\circ}$, respectively. The average differences between their bearings and between their positions were $-1.29^{\circ}$ and 68.8m, respectively. From these results, we concluded that if the ROT, COG, SOG, and HDG informations are correct, the AIS system can be improved the prediction of a target ship's path and the OOW(Officer of Watch) s ability to anticipate a traffic situation more accurately.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.326-329
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• 2005

Proton exchange membrane (PEM) should be sufficiently hydrated with proper water management to maintain a good ionic conductivity and performance of a PEM fuel cell. However. cathode flooding resulting from excess water can impede the transport of reactants and hence deteriorate the fuel cell performance. For the PEM fuel cell to be commercially viable as vehicle or portable applications, the flooding on the cathode side should be minimized during the fuel cell operation. In this study, visualization technique was applied to understand the cathode flooding phenomena on the cathode side of a PEM fuel cell. To this end. a transparent PEM unit fuel cell wi th an act ive area of $25cm^2$ was designed and manufactured to allow for the visualization of cathode channel with performance characteristics. Two-phase flow resulting from the electro-chemical reaction of fuel cell was investigated experimentally. The images photographed by CCD camera with cell operating temperatures $(30\~50^{\circ}C)$ were presented. Results indicated that the flooding on the cathode side first occurs near the exit of cathode channel. As the operating temperature of fuel cell increases. it was found that liquid water droplets tend to evaporate easily and it can have an influence on lowering the flooding level. It is expected that this study can effectively contribute to the detailed researches on modeling water transport of an operating PEM fuel cell including two-phase flow phenomena.

• Journal of Korean Society of Transportation
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• v.25 no.6
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• pp.65-77
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• 2007

A two-way left-turn lane is a continuous center left-turn lane that could be used as a deceleration and refuge area for both directions of left-turning vehicles. TWLTL's have been used effectively for access management treatment when applied to a highway that has wide-spread left turning traffic demand and a high-density of side streets. In this study, an effective analysis was carried out using a computer-based simulation tool, VISSIM, in order to evaluate performance and safety effects of TWLTLs and develop a warrant. In conclusion, the results indicated that there was a remarkable decrease of through and left-turning vehicle travel time delay on the main road and improvement of traffic safety.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.3
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• pp.595-602
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• 2000

This paper is aimed at developing an location tracking system of mobile station based on currently available mobile communication network or mobile Phone and PCS(Personal Communication System). When the location tracking of mobile stations is in services, Emergency-119, all of crime investigation, effective urban traffic management and the safety protection of Alzheimer＇s patients can be available. In order to track the location of the mobile and base station, assumption in this paper is to use the statistic characteristics of LOS when modeling the standard noise in case that radio path is LNOS environment. The standard variation of the standard noise is $\pm150$. First, location is estimated by the positioning algorithms of TOA and TDOA and compared each other. Second, after canceling the standard noise by Kalman filter, location is estimated by the above two positioning algorithms. Finally, the location by the Kalman filter and two positioning algorithms is estimated by smoothing method. As a result, 2 dimensional average location error is imvoved by 51.2m in TOA and 34.8m in TDOA when Kalman filer and two positioning algorithms are used, compared with the two positioning algorithm used. And there is 3 more meter improvement after smoothing than Kalman filer and two positioning algorithms used.

• Journal of Korean Library and Information Science Society
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• v.40 no.4
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• pp.261-286
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• 2009

Despite much recent researches on career development or career movement, research on domestic librarians' career development are rarely conducted. Therefore this study examined the career movement of directors of public libraries as one aspect of research for librarian workforce. This study surveyed directors of public libraries and analyzed the following points; age of first job, initial type of career, age when they became the director. Factors affecting career move, career paths, working years by career steps, the number of changing department before director, training opportunities for manager, and so on. This study also analyzed what kinds of efforts they exerted to become a director. The result showed 45.1% of respondents made an effort to increase knowledge and skills, 23.6% undertook an effort to improve their honesty and gain their integrity, 12.8% underwent an effort to increase competence and self-management efforts in about the library. Through analyzing the career development process of public library directors, we can find the ideal path for career development to become a director of public libraries.

• Research in Community and Public Health Nursing
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• v.13 no.2
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• pp.292-305
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• 2002

Purpose: The purpose of this study was to conduct a systematic assessment on the level of health status, and quality of life of the health care beneficiaries registered in health management programs of public health centers. In order to investigate the level of health status and the quality of life and to find factors affecting them, the PRECEDE model, that was developed by Green, et al. for the purpose of a comprehensive diagnostic research, was used. Method: The subjects were 81 residents who resided K-gu, Seoul. Data were collected from September, 1999 to August, 2000 using a self reported questionnaire. The data were analyzed by descriptive statistics, t-test, Kruskall-Wallis test, Pearson's correlation coefficient. and path analysis. Results: 1. The quality of life and the level of health promoting lifestyle were moderate or more, but were not significantly different by sex, age, marital status, educational level. occupation, and monthly household income. 2. Self-efficacy was significantly correlated to be a perceived benefit, social support and health-promoting lifestyle. Perceived benefit had a significant correlation with social support and health promoting lifestyle. There was also a significant correlation between the level of satisfaction, and the availability of the health promotion program. 3. Social support, health promoting lifestyle, and health status were found to influence the quality of life directly, whereas self efficacy and perceived benefit affected the quality of life indirectly through social support. Conclusion: The results of this study suggest that the health promotion program should include strategies to strengthen self efficacy and perceived benefit to enhance social support, and to encourage health promoting behaviors in order to improve the quality of life of the health care beneficiary.

• Journal of KIISE:Information Networking
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• v.31 no.6
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• pp.620-632
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• 2004

IP is not suitable for mobile nodes by network-based routing because mobile nodes are dynamically change their network attachment point. Mobile-IP is an IETF standard providing continuous access to the Internet for mobile nodes, but it has the triangle routing problem. Also it has a performance degradation problem by massive packet loss during layer 3 handoff of mobile nodes. Especially, two IETF multicast support schemes for Mobile-IP do not guarantee the quality of realtime multimedia services because they have several problems such as long routing path, packet duplication(hi-directional tunneling) and massive packet loss(remote subscription). In this paper, we propose a lossless remote subscription scheme that guarantees the quality of realtime multimedia services over Mobile-IP. From the result of simulation, we verified that the proposed scheme in this paper can reduce the delay time of remote subscription by the effect of the low latency handoff scheme that is extended to apply to the multicast group management and it requires only 0.58% buffer spaces of the previously proposed lossless remote subscription scheme.

• Journal of KIISE
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• v.42 no.6
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• pp.734-747
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• 2015

The aging population and the advancement of science and technology are transforming the healthcare industry to focus on health management for the prevention of diseases. The U-health and remote healthcare services have not yet achieved the social agreement in the nation; however, these have been extensively used in the global scale. The innovation of user experience through cognitive computing are expected to increase the health effects of consumers, by converging with healthcare information services. This study suggests the conceptual model of healthcare information service converged with cognitive computing. Then, the acceptance factors for consumers have been investigated. For this purpose, reliability and validity analysis have been conducted using an online survey. The path analysis was performed to verify the hypotheses and moderating effect based upon the gender, by using structural equation modeling.

• Journal of the Korean Society of Costume
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• v.60 no.8
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• pp.100-117
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• 2010

The cosmetics industry is executing the experiential marketing strategy, which focuses the brand experiential experience for the connection with consumers and differentiated strategy for the company's brand image, according to the expansion of quality service, which increasingly consume a diverse experience. Among these, the low-priced cosmetics market is trying a variety of experiential marketing to provide positive experience of their product and their brand through a unique service or event to stimulate the motions of young woman, who are changing rapidly, and is actively utilizing the means of marketing to form brand equity for these experiential marketing. Therefore, this study is to find out the effect of customer experiential on the brand equity through a variety of experiential marketing of low-priced cosmetics brand and based on the result, we were able to find out that the experiential marketing is also used as important means of marketing for low-priced cosmetics market to secure the brand equity and to maintain long-term relationship with the customer. This is expected to provide strategic and practical implications to the cosmetic marketing managers for customer management and this will recognize the importance of customer experiential in cosmetic marketing and suggest proper marketing strategy plan. In this study, the multiple regression analysis was mainly uses to find out the influence between the variables for low-cost cosmetic brand but we're hoping to execute a study, which directly and indirectly covers the complete path by using the various parameters, which can be effected on the brand equity.