• Journal of Satellite, Information and Communications
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• v.2 no.2
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• pp.1-9
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• 2007

In this paper, we describe the performance degradation of satellite Wibro system and compensation method in the high-speed railroad channel environment. High-speed railroad channel environment is divided into LOS channel and tunnel. In the LOS channel, signal blocking caused by railroad power feeder structures can be a critical problem which is can be solved with antenna diversity. On the other hand, multi path interference phenomenon, representable by propagation model of Optic Fiber, occurred in the tunnel may be another obstacle. These satellite Wibro system performance degradations in railroad channel environment are addressed and adequate compensation methods are proposed and verified through computer simulation. In addition, the ICI caused by Doppler shift in OFDM system is analyzed with its compensation method.

• The KIPS Transactions:PartA
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• v.10A no.4
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• pp.411-418
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• 2003

After the general and multi-function PC age is gone, A new type of computing devices is developing. The need of consumer increases a new device with very necessary function instead of all-mighty functional PC. The operating system of this works is linux because of open source licensing and a strong developer community. The Post PC industry represents and environment that will foster dramatic growth and new development. The adoption of embedded linux in this market will not be driven by simple replacement of expensive proprietary operating systems. In this paper we describe the practical design and implementation project of Post-PC Platform. We illustrate "the development of digital consumer Post-PC platform technology," focus the fourth project, and describe the development works of this project.s project.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.9B
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• pp.1057-1065
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• 2011

In order to achieve the ease of development and to facilitate the maintenance of codes for complex Ajax (Asynchronous Java Script and XML)-based web clients, this paper proposes a CVC (Communicator-View-Controller) architecture pattern by modifying the well-known MVC (Model-View-Controller) framework. By composing the Communicator of codes for asynchronous data retrieval, which is common to Ajax-based clients, the proposed architecture pattern is able to cut out the graphic design related codes to constitute the View layer. Based on such declarative generalization of complex web-client codes, Ajax-related codes can be easily modularized and efficiently reused in development and maintenance stages, and graphics design can be done separately regardless of the other business logic related codes development, resulting in highly efficient development and maintenance of complex Ajax-based web clients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.5078-5090
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• 2013

This study was to identify the relationship among small-medium sized hospitals nurse's career plateau, self-efficacy, job embeddedness and turnover intention. The study was conducted through a survey on 217 nurses in five small-medium sized hospitals in J city. The data were collected from August 5, 2013 to August 20, 2013. The data were analyzed by SPSS/WIN 18.0 program. The mean score of turnover intention was 3.07. The positive correlations between career plateau and turnover intention were found, but the negative correlation between self-efficacy, job embeddedness and turnover intention were found. The significant factors influencing turnover intention were job embeddedness, present clinical career, career plateau and work unit. To decrease turnover intention, therefore, nursing managers need to develop the nurse retention program for increasing job embeddedness and apply to nursing field.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.230-235
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• 2016

The purpose of this study was to investigate the stress from work and stress coping methods of hospital nurses. The study design was a descriptive survey research. There were a total of 168 hospital nurses included in this study. Data were analyzed by t test, ANOVA (Sheffe's test), and Pearson's correlation coefficient using SPSS/WIN17.0. The stress level from work was 4.27 and stress coping methods was 2.67. Marital status was positively correlated with education level, current department, career duration, and current position. The education level was positively correlated with career period and current position. Current position was positively correlated with stress coping methods. A further follow-up study on nurses in hospital is necessary to relieve stress from work and to increase better stress coping methods. Moreover, to decrease the stress from work of nurses, it is necessary to develop a program that helps them to cope with stress. In addition, these findings contribute to the development of such program.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.5
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• pp.10-15
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• 2017

Research interest has strongly focused on developing a method for effectively transmitting bio-signals over a distance using a wireless wearable device. In this paper, we describe a procedure for the design and fabrication of a wearable antenna based on embroidering conductive threads to clothing capable of transmitting electrocardiogram signals. 3D electromagnetic simulation software and embroidery software were used to design and fabricate the conductive thread-based antenna, respectively. The measurement results show that the reflection coefficient of the fabricated antenna prototype exhibits excellent antenna impedance matching characteristics of less than -10dB in the Zigbee 2.4GHz frequency band. We also verified that the electrocardiogram data could be effectively received and monitored in real-time by a receiver 220m away from the transmitter.

• KIISE Transactions on Computing Practices
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• v.23 no.6
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• pp.343-349
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• 2017

Combat modeling and simulation (M&S) of large-scale computer generated forces (CGFs) enables the development of even the most sophisticated strategy of combat warfare and the efficient facilitation of a comprehensive simulation of the upcoming battle. The DEVS-POMDP framework is proposed where the DEVS framework describing the explicit behavior rules in military doctrines, and POMDP model describing the autonomous behavior of the CGFs are hierarchically combined to capture the complexity of realistic world combat modeling and simulation. However, it has previously been well documented that computing the optimal policy of a POMDP model is computationally demanding. In this paper, we show that not only can the performance of CGFs be improved by an efficient POMDP tree search algorithm but CGFs are also able to conveniently learn the behavior model of the enemy through case studies in the scenario of counterfire warfare and the scenario of a mechanized infantry brigade's offensive operations.

• Journal of Aerospace System Engineering
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• v.14 no.1
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• pp.36-43
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• 2020

The start of satellite thermal design was to predict the worst operating environment through analysis of the thermal environment of the operation orbit. Because the satellites have different types of operating trajectories for their mission, the exposed thermal environment also varies. Thus, it is necessary to analyze in consideration of the orbital conditions, and a design was performed to guarantee thermal stability for the worst case defined through the analysis. The orbital thermal environmental analysis required an understanding of the basic orbit mechanics and the heat exchange relationship between the space environment and satellite. The purpose of this paper was to provide an understanding of the orbital thermal environment analysis by providing basic data on the space thermal environment in the earth-orbit and describing thermal relations that calculate the amount of space heat inflow into satellites. Additionally, an example of a virtual satellite shows the overall process of analyzing the orbital thermal environment during a mission lifetime.

• Annual Conference on Human and Language Technology
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• 2018.10a
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• pp.172-175
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• 2018

환자의 병력을 서술하는 임상문서에서 임상 개체명들은 그들 사이에 개체명이 아닌 단어들이 위치하기 때문에 거리상으로 서로 떨어져 있고, 임상 개체명인식에 많이 사용되는 조건부무작위장(conditional random fields; CRF) 모델은 Markov 속성을 따르기 때문에 서로 떨어져 있는 개체명 라벨 간의 전이 정보는 모델의 계산에서 무시된다. 본 논문에서는 라벨링 모델에 서로 떨어진 개체명 간 전이 관계를 표현하기 위하여 CRF 모델의 구조를 변경하는 방법론을 소개한다. 제안된 CRF 모델 디자인에서는 모델의 계산효율성을 빠르게 유지하기 위하여 Markov 속성을 유지하는 1차 모델 구조를 유지한다. 모델은 선행하는 개체명의 라벨 정보를 후행하는 개체명 엔터티에게 전달하기 위하여 선행 개체명의 라벨을 뒤 따르는 비개체명 라벨에 전이시키고 이를 통해 후행하는 개체명은 선행하는 개체명의 라벨 정보를 알 수 있게 된다. 라벨의 고차 전이 정보를 전달함에도 모델의 구조는 1차 전이 구조를 유지함으로 n차 구조의 모델보다 빠른 계산 속도를 유지할 수 있게 된다. 모델의 성능 평가를 위하여 서울대학교병원 류머티즘내과에서 퇴원한 환자들의 퇴원요약지에 병력과 관련된 엔터티가 태깅된 평가 데이터와 i2b2 2012/VA 임상자연어처리 shared task의 임상 개체명 추출 데이터를 사용하였고 기본 CRF 모델들(1차, 2차)과 비교하였다. 피처 조합에 따라 모델들을 평가한 결과 제안한 모델이 거의 모든 경우에서 기본 모델들에 비하여 F1-score의 성능을 향상시킴을 관찰할 수 있었다.

• Journal of Convergence for Information Technology
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• v.8 no.1
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• pp.53-58
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• 2018

The study was done to compare quality of life by family therapy, self-esteem f teem insight factors which explain quality of life in individuals with schizophrenic patients. A questionnaire survey was conducted with 125 schizophrenia people in C region. The data were analyzed by SPSSWIN 21.0, t-test, ANOVA and Pearson correlation coefficient calculation and multiple regression analysis. The results were as follows. Impact quality of life of clients showed significant difference by religion, support team(p<.05). Quality of life were positively correleated with self-esteem and family support. Multiple regression analysis showed that 49.5% of the self esteem, insight, family support showed the quality of life. Development of programs for strengthening family support and self esteem is required for proper quality of life.