• Journal of Advanced Navigation Technology
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• v.19 no.5
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• pp.345-353
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• 2015

In this paper, we proposed an information fusion method for enhancement of automatic dependent surveillance - broadcast (ADS-B) system which is one of the next generation navigation system. Although ADS-B provides better performance than traditional radar, ADS-B still has error due to dependence of global navigation satellite system (GNSS) information. In this paper, we improved the ADS-B performance using information fusion of multilateration (MLAT) and wide area multilateration (WAM). Information fusion provides accurate data compared to original data. Mostly, information fusion methods use Kalman filter or IMM(interacting multiple model) filter as a subfilter. However, we used Robust IMM filter as a subfilter to improve the aircraft tracking performance. Also, we use actual ADS-B data not virtual data to increase reliability of our information fusion method.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.2
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• pp.26-31
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• 2012

A new operational concept for the CNS/ATM using the digital data communication technology and satellite navigation system is being implemented globally and the United States is the first country to apply UAT ADS-B system for general aviation. Korea also has plan to build ADS-B system for aeronautical surveillance to monitor low altitude flight of light aircraft and ultra-light flying device and the research to develop UAT ADS-B equipment is being carried out. This paper presents the application method of UAT ADS-B to support test operation with case study of foreign UAT ADS-B operation and survey of domestic environment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.5
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• pp.1373-1387
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• 2012

Contextual advertising is an important revenue source for major service providers on the Web. Ads classification is one of main tasks in contextual advertising, and it is used to retrieve semantically relevant ads with respect to the content of web pages. However, it is difficult for traditional text classification methods to achieve satisfactory performance in ads classification due to scarce term features in ads. In this paper, we propose a novel ads classification method that handles the lack of term features for classifying ads with short text. The proposed method utilizes a vocabulary expansion technique using semantic associations among terms learned from large-scale search query logs. The evaluation results show that our methodology achieves 4.0% ~ 9.7% improvements in terms of the hierarchical f-measure over the baseline classifiers without vocabulary expansion.

• Journal of Korea Game Society
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• v.16 no.6
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• pp.69-78
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• 2016

Outdoor ads such as billboards, banners or posters frequently appears in street maps of FPS games. In this paper, we propose a method for the automatic placement of outdoor advertising in the city area of FPS games. Outdoor ads are from real world products or enterprises and they are managed in a server computer. If the ads data are updated, the advertisements are automatically placed again without modifying source codes. When placing ads, we utilize the real world location of the game player regarding commercial spheres of ads and service types of real world shops. We evaluate priority scores for the available ads based on the collected real world properties and higher priority ads are preferentially placed on the map. The proposed ad placement method makes the game players feel affinity for the placed ads and also it increases the advertising effect.

• ETRI Journal
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• v.43 no.2
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• pp.324-331
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• 2021

Space-based automatic dependent surveillance-broadcast (ADS-B) is an important emerging augmentation of existing ground-based ADS-B systems. In this paper, the problem of space-based ultra-long-range reception processing of ADS-B signals is described. We first introduce a header detection method for accurately determining the pulse position of a weak ADS-B signal. We designed a signal encoding method, shaping method, and fitness function. We then employed a genetic algorithm to perform high-precision frequency and phase estimations of the detected weak signal. The advantage of this algorithm is that it can simultaneously estimate the frequency and phase, meaning a direct coherent demodulation can be implemented. To address the computational complexity of the genetic algorithm, we improved the ratio algorithm for frequency estimation and raised the accuracy beyond that of the original ratio algorithm with only a slight increase in the computational complexity using relatively few sampling points.

• Journal of Advanced Navigation Technology
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• v.20 no.3
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• pp.203-209
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• 2016

Among the various fields in the communications, navigation, and surveillance/air traffic management (CNS/ATM) scheme, the surveillance field, which includes an automatic dependent surveillance - broadcast (ADS-B) system and a multilateration (MLAT) system, is implemented using satellite and digital communications technology. These systems provide better performance than radar, but still incur position error. To reduce the error, we propose an efficient information fusion method called the reweighted convex combination method for ADS-B and MLAT systems. The reweighted convex combination method improves aircraft tracking performance compared to the original convex combination method by readjusting the weights given to these systems. In this paper, we prove that the reweighted convex combination method always provides better performance than the original convex combination method. Performance from the fusion of ADS-B and MLAT improves an average of 51.51% when compared to the original data.

• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1600-1609
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• 2017

The accelerator-driven subcritical system (ADS) is driven by a neutron source from spallation reactions introduced by the injected proton beam. Part of the neutron source has energy as high as a few hundred MeV to a few GeV. The effects of high-energy source neutrons ($E_n$ > 20 MeV) are usually approximated by energy cut-off treatment in practical core calculations, which can overestimate the predicted proton beam current in the ADS design. This article intends to quantize this effect and propose a way to solve this problem. To evaluate the effects of high-energy neutrons in the subcritical core, two models are established aiming to cover the features of current experimental facilities and industrial-scale ADS in the future. The results show that high-energy neutrons with $E_n$ > 20 MeV are of small fraction (2.6%) in the neutron source, but their contribution to the source efficiency is about 23% for the large scale ADS. Based on this, a neutron source efficiency correction factor is proposed. Tests show that the new correction method works well in the ADS calculation. This method can effectively improve the accuracy of the prediction of the proton beam current.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.17 no.4
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• pp.450-459
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• 2010

Purpose: The purposes of this study were to identify awareness and attitudes toward advance directives (ADs) among Korean adults and to examine various opinions in the utilization of ADs among young, middle-aged, and older adults. Methods: Data were collected using a structured questionnaire from 384 adults selected by a quota sampling method on the basis of age. Results: The majority of participants preferred that they themselves would be the primary decision maker. Most of them were unaware of the option of ADs but supported the utilization of ADs. Most of the participants preferred detailed descriptions on end-of-life decisions in ADs but wanted to allow some leeway in following it. Significant differences were found among age groups in terms of the preferences regarding the utilization of ADs. Conclusion: It is suggested that nurses make efforts to educate the general public about ADs and facilitate advance care planning, which focuses on the process of communication on end-of-life preferences within the social network of relationships.

• Journal of Ocean Engineering and Technology
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• v.17 no.6
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• pp.16-22
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• 2003

In this paper, the method of determining the economically-optimal design section of rubble mound breakwater, using ADS program, was studied to supplement the deterministic approach. First of all, the design waves are computed, according to the return periods, using the Weibull distribution from the data of waves at the location of the breakwater. In order to take an optimal section, according to the return periods, the ADS program was used. The restriction conditions and objective functions are decided from the references of the specifications and standard manuals for Coastal and Harbor Construction Work. Results from this study support the ADS program as an appropriate method for determining the economically-optimal section of rubble mound breakwater, comparing the construction costs and the initial and damage repair costs for its life time.

• Journal of Hospice and Palliative Care
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• v.25 no.4
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• pp.139-149
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• 2022

Purpose: The purpose of this study was to promote awareness of the need for advance directives (ADs) and to provide baseline data for the development of a nurse training program about ADs. Methods: Nurses at eight long-term care hospitals in Busan and South Gyeongsang Province (N=143) were recruited using the random sampling method from December 2018 to January 2019. Data were obtained using a structured self-reported questionnaire to assess their knowledge, experience, and attitudes regarding ADs. Data were analyzed in SPSS 22.0 using descriptive statistics, the t-test, analysis of variance, the Scheffé test, Pearson's correlation coefficient, and stepwise multiple regression analysis. Results: The mean scores were 7.79±1.39 points for knowledge, 1.92±2.00 points for experience, and 2.80±0.24 points for attitudes regarding ADs. Knowledge and experience (r=0.32, P<0.001) had a positive correlation with knowledge and attitudes (r=0.17, P=0.39). Conclusion: According to the results, nurses generally had a high level of knowledge regarding ADs, which resulted in a positive attitude toward ADs. However, they had little experience with ADs. Therefore, nurses' must develop both direct and indirect experience with ADs using a practical training program to strengthen their clinical competency regarding ADs.