• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.10B
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• pp.639-647
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• 2005

When a DEV associates with an existing WPAN, the PNC checks the capabilities of the new DEV to see if it is more capable to be the PNC of the piconet based on the criteria defined in the IEEE Std 802.15. If the new DEV is more capable and the current security policies allow it, then the PNC has the option of handing over control of the piconet to the DEV that has just joined. And, If the PNC is shutting down or wants to leave the WPAN, it also uses the handover process to give control to another DEV in the piconet. However, IEEE 802.15.3 checks only DEV capability information for more PNC capable. For PNC selection, it should consider the radio coverage of new PNC capable DEVs. So, we propose the method of PNC selection with accessibility check. This method manages PNC candidate list in the current piconet. In this paper, we analyze accessibility problems for PNC selection in section 2. In section 3, we explain CI(Configuration Inquiry) process which is proposed by Sony Corporation and propose PCI(PNC Candidate Inquiry) process. Also, we perform numerical analysis to compare PCI process with CI process in section 4. Finally, we conclude in section 5.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.2A
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• pp.114-126
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• 2011

Video streaming over wireless multi-hop networks(WMNs) contains the following challenges from channel fading and variable bandwidth of wireless channel, and it cause degradation of video streaming performance. To overcome the challenges, currently, WMNs can use Forward Error Correction (FEC) mechanism. In WMNs, traditional FEC schemes, E2E-FEC and HbH-FEC, for video streaming are applied, but it has long transmission delay, high computational complexity and inefficient usage of resource. Also, to distinguish network status in streaming path, it has limitation. In this paper, we propose monitoring-based coordination of network-adaptive hop-to-end(H2E) FEC scheme. To enable proposed scheme, we apply a centralized coordinator. The coordinator has observing overall monitoring information and coordinating H2E-FEC mechanism. Main points of H2E-FEC is distinguishing operation range as well as selecting FEC starting node and redundancy from monitored results in coordination. To verify the proposed scheme, we perform extensive experiment over the OMF(Orbit Measurement Framework) and IEEE 802.1la-based multi-hop WMN testbed, and we carry out performance improvement, 17%, from performance comparison by existing FEC scheme.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37C no.12
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• pp.1318-1327
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• 2012

With the recent increased risk of livestock disease spread and human infection, livestock disease control has become very important. Consequently, there has been an increased attention on an implantable real-time monitoring and traceability system for individual cattle. Therefore, we have developed a robust monitoring and traceability system based on an implantable MFAN/RFID sensor tag. Our design combines the MFAN technology that is capable of robust wireless communication within cattle sheds and the 900MHz RFID technology that is capable of wireless communication without battery. In MFAN/RFID implantable sensor tag monitoring system, UHF sensor tag is implanted under the skin and accurately monitors the body temperature and biological changes without being affected by external environment. In order to acquire power needed by the tag, we install a MFAN/RFID tranceiver on the neck of cattle. The MFAN coordinator passes through the MFAN node and the RFID-reader-combined MFAN/RFID transceiver and transmits/receives the data and power for the sensor tag. The data stored in the MFAN coordinator is transmitted via the internet to the livestock history monitoring system, where it is stored and managed. By developing this system, we hope to alleviate the problems related to livestock disease control.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.4
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• pp.525-534
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• 2018

This study evaluated the various qualifications that can be linked to employment similar to the medical laboratory technology major. The qualifications for employment outside the medical laboratory technology major are industrial health instructor, doping control officer, audiologist, sign language interpreter, health education specialist, claim adjuster, Korea life underwriter, administrative manager, hospital administrator, insurance review manager, and hospital coordinator. The qualifications for employment similar to the medical laboratory technology major include the clinical research coordinator, clinical research associate, anatomist, analytical chemistry analysts, hazardous materials industry engineers, biotechnologist, biosafety managers, biotechnology technicians, medical device quality officers, animal care nurse, industrial engineer hazardous material, bioprocess engineer, biosafety officer, certified technology consultant, director of medical device quality control, laboratory animal technician, animal nursing technician, and cruise medical manager. Therefore, it is necessary to conduct a social analysis survey of the various qualifications currently held by medical technologists. In addition, it will be necessary to investigate the current status of medical technologists working in other fields. In the future, medical technologists should expand the scope of their work through efforts to strengthen their individual work capacity, share cases, and strengthen their expertise.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.14 no.3
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• pp.340-350
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• 2007

Purpose: This study was done to construct a quality of life (QOL) model for recipients of a liver transplant. Method: In consideration of the main factors influencing QOL in recipient of liver transplants, a hypothetical model was constructed with 16 paths. A questionnaire was used to collect data from recipients of liver transplants who were being followed at one of 3 university hospitals. For the final analysis, there were 189 completed questionnaires and the hypothetical model was verified through covariance structure using LISREL program. Results: Overall fitness indices of hypothetical model were GFI= .99, AGFI= .97, NNFI= .96 and RMR=.020. After considering modification indices and paths that proved not to be significant and to improve model fitness, the hypothetical model was modified. In the final model, 3 paths from the hypothetical model were excluded. Overall fitness indices of the final model were GFI= .99, AGFI= .98, NNFI= .98 and RMR= .020. Eleven of fifteen paths proved to be significant. QOL was influenced by duration after transplantation, perceived health status, self-esteem, uncertainty, social support, self efficacy and depression and these variables explained 65% of the variance. Conclusion: This study presents a theoretical model for QOL for recipients of a liver transplant. Based on the results of this study and to improve QOL for recipients of a liver transplant, it is suggested that interventions to re-enforce self efficacy and self-help are needed.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.182-183
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• 2008

환기시설이 열악한 도시 지하철역 내의 대기환경은 지상보다 열악할 수밖에 없다. 현재 지하철역을 주로 사용하는 시민들의 안전을 보호 하고 지하철의 대기환경을 개선하기 위해 스크린 도어, 자동 제어 환기시설, 종합 영상 감지시스템 등 다양한 노력을 기울이고 있다. 하지만 일부 지하철역에 설치되어 있는 공기질 모니터링 시스템은 수입품에 의존하고 고가의 장비이므로 초기설치 비용뿐만 아니라 유지보수의 어려움을 겪고 있다. 본 논문에서는 이러한 문제점을 해결하기 위해 무선 센서 네트워크 기술을 적용하여 저가형 대기환경 모니터링 시스템을 개발했다. 이 시스템의 구성은 센서노드(ZED : ZigBee End Deice), 네트워크 코디네이터(ZCM : ZigBee Coordinator Modem), 수신서버로 구성된다. 지하철역 내부의 미세먼지, CO2, CO, 온습도, VOCs 데이터를 센싱할 수 있는 확장 센서보드를 설계한 후, 지하공간에서의 열악한 통신환경에서 QoS를 보장할 수 있도록 ZigBee 라우팅 기술을 이용한 센서노드(ZED)를 인터페이스하여 하나의 통합된 대기환경 센서 노드(ZED)를 개발했다. 또한 수신서버에 USB방식으로 연결되어 각각의 ZED로부터 데이터를 수신하는 센서노드(ZCM)과 전송된 데이터를 저장 및 처리하여 언제 어디서나 누구든지 인터넷을 통해 확인 가능하도록 지하철 대기환경 모니터링을 위한 수신서버를 개발했다.

• 한국HCI학회:학술대회논문집
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• 2006.02a
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• pp.333-338
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• 2006

최근 사용자에 대한 많은 정보를 얻는 것이 가능해지면서, 데이터마이닝 기법이나 Contents 추천 기법을 이용한 맞춤형 서비스가 가능하게 되었다. 특히, 대부분의 사람들에게 TV 프로그램 시청은 여가생활시간에서 가장 높은 비중을 차지 하고 있다. 따라서, 보다 지능적인 TV 프로그램 서비스를 제공하는 기술에 대하여 관심이 고조되고 있다. 본 논문에서는 TV-Anytime을 이용하여 개인화된 Electronic Program Guide (EPG)를 생성하고, 개인화된 EPG 정보를 활용하여 시청자에게 맞춤형 TV 프로그램 서비스를 제공하는 시스템에 대한 연구 결과를 제시한다. 또한 시청자의 시청패턴과 TV 프로그램 선호도를 바탕으로 시청자가 원하는 프로그램을 추천하는 TV Program Recommender Agent와 방송 및 TV 프로그램에 대한 대화를 담당하는 TV Program Helper Agent, 시스템 조정 및 메시지 전달을 담당하는 Coordinator Agent로 이루어진 멀티에이전트 기반 시스템 구조를 제시한다.

• Journal of Korean Academy of Nursing
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• v.36 no.6
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• pp.1012-1022
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• 2006

Purpose: The purpose of this phenomenological study was to understand the experiences in the transplantation coordinators' practice. Method: Data was collected through a tape-recorded in-depth interview from nine participants who were transplantation coordinators of their hospitals. It was analyzed using the phenomenological method proposed by Colaizzi(1978). Results: From significant statements, six categories of themes were integrated into the essential structure of the experiences of transplantation coordinators. Six categories of themes were 'continue to be professional during dash this way and rush that', 'burden due to persistent heavy work', 'the uniqueness in family care of the brain-dead patients', 'support of family and a professional group', 'worthiness and achievement of the patients' recovery', and 'establishment of self-confidence as a coordinator'. Conclusion: Although the transplantation coordinators played various roles, they had a conflict in role identity due to poor working environments. The results of this study suggested that development of an educational program, an increase in understanding for the coordinators' role, and institutional support for better working conditions are needed to get professional acknowledgement for transplantation coordinators.

• Journal of Korean Academy of Nursing
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• v.38 no.5
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• pp.676-684
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• 2008

Purpose: The purpose of this study was to identify the risk factors for falls and to suggest data for developing a program for preventing falls. Methods: This was a case-control study in five university hospitals and a general hospital. In total, 216 patients over the age of 18 yr admitted from January 1 to December 31, 2007 participated. One hundred eight patients with experience of falling were matched by gender, age level, diagnosis, and length of stay with 108 patents with no experience of falling admitted on the same unit. A quality assurance coordinator nurse in each hospital examined 35 fall risk factors developed by researchers. Results: In acute hospitals, history of falls, orientation ability, dizziness or vertigo, general weakness, urination problems, transfer/mobility difficulty, walking dependency, impatience, benzodiazepines, diuretics, and vasodilators showed significance on adjusted-odds ratios for fall. Logistic regression analysis was performed to elucidate the factors that influence falls. The probability of falls was increased by dizziness/vertigo, general weakness, and impatience/agitation. Conclusion: This finding can be used as a useful resource in developing nursing intervention programs to predict and prevent the falls of inpatients.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.6
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• pp.2848-2869
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• 2017

Mobile Wireless Sensor Networks (MWSN) are usually constrained in energy supply, which makes energy efficiency a key factor to extend the network lifetime. The management of the network topology has been widely used as a mechanism to enhance the lifetime of wireless sensor networks (WSN), and this work presents an alternative to this. Software Defined Networking (SDN) is a well-known technology in data center applications that separates the data and control planes during the network management. This paper proposes a solution based on SDN that optimizes the energy use in MWSN. The network intelligence is placed in a controller that can be accessed through different controller gateways within a MWSN. This network intelligence runs a Topology Control (TC) mechanism to build a backbone of coordinator nodes. Therefore, nodes only need to perform forwarding tasks, they reduce message retransmissions and CPU usage. This results in an improvement of the network lifetime. The performance of the proposed solution is evaluated and compared with a distributed approach using the OMNeT++ simulation framework. Results show that the network lifetime increases when 2 or more controller gateways are used.