• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.9B
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• pp.775-785
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• 2008

We identify the problem of the current IEEE 802. lie HCCA (Hybrid Coordination Function Controlled Channel Access) scheduler and its numerous variations, that the queue information cannot be notified to the Hybrid Coordinator (HC) timely, therefore the uplink delay lengthens unnecessarily. We suggests a simple solution and a couple of implementation practices, namely the Adaptive Scheduler with RTS/CTS (ASR) and Adaptive Scheduler with Data/Ack (ASD). They are both further elaborated to emulate the Deficit Round Robin (DRB) scheduler. They are finally compared with existing exemplary schedulers through simulations, and shown to perform well.

• The Journal of Society for e-Business Studies
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• v.4 no.2
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• pp.209-220
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• 1999

Quick response in the textiles and clothing industry is widely recognized at a strategic concept implemented by information technology to transfer changes in customer needs to the final product as soon as possible. This paper addresses which factors should affect the adoption of quick response systems in Korea. We surveyed 108 companies in the textile and clothing industry by using a questionnaire. We asked whether they adopted QR or not, and measured the usage level of QR-related ITs and the level of both internal and external factors in Likert's scale. We conducted multiple linear regression to analyze the data collected by using SAS. The findings are as follows: The adoption of QR, measured by the usage level of QR-related ITs, is positively affected by internal factors such as the recognition of QR concept and the capability for IT applications and by external factors such as the overall informating level of the industry, the needs for cooperation between organizations, and the leadership as an industry coordinator.

• Journal of Digital Contents Society
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• v.13 no.4
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• pp.525-530
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• 2012

Wireless sensor networks consist of resource constraint devices which typically send data measured by sensors attached to the end devices towards a coordinator. One of the best solution for wireless sensor networks is ZigBee, where it is wireless standard introduced for low power, low cost wireless communication with moderate data rates. In this paper, we present porting of Z-Stack and implementation of UART on the TI CC2530. We show that our implemented board works correctly in terms of transmitting and receiving data via serial port.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.4
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• pp.209-213
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• 2007

In this paper, we propose more efficient implementation architecture for realizing combination of heterogeneous routing protocols in wireless mesh routes. For realizing heterogeneous routing protocol in wireless mesh router, the following should be considered; which position in OS platform protocols should be implemented, how to define the common API for multiple routing protocols, how to provide architecture for providing high data transfer throughput and for supporting multi platform, and finally how to verify the throughput of protocol by using simulator. For solving those consideration, we propose HRPC(Heterogeneous Routing Protocol Coordinator) and describe the method for testing the protocols.

• Korean Journal of Hospice Care
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• v.3 no.1
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• pp.12-30
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• 2003

We all human beings, should be reached the terminal of life in the world. There is the only difference between that comes suddenly or slowly. Persons who should be come the terminal stage suddenly due to disease, especially, malignancy, are Hospice patients. Hospice work is the work of all of us because anyone, anywhere, whenever can be suffered in terminal stage. The characters of Hospice-care are total care of wholistic human beings, comprehensive total assessment of the life and the team work composed of diverse team-members, for example, doctors, nurses, social workers, physical therapists, psychologists, ministers & volunteers. The care manager of the total care(the coordinator of Hospice care), should be worked systemically and, rationally. The comprehensive assessment concept should be entered to the infra-consultant of terminal care-program. The care manager should be have the ability of comprehensive assessment for terminal patients. It will also help standardization of Hospice, and application of medical insurance and social security.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2003.11a
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• pp.207-212
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• 2003

Today, demands on the housing that is fit f3r each and every person and restoration of the community are increasing rapidly. USA Europe and Japan have been constructing Co-operative Housing as an alternative residence. Therefore this study has a purpose to show the characteristics of related companies and the process of Japanese Co-operative Housing through the field trip in Japan.

• Korean Journal of Adult Nursing
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• v.24 no.5
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• pp.454-465
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• 2012

Purpose: The aim of this study was to understand the nurses' experiences of caring for demented older persons in geriatric in care facilities. Methods: The subjects were ten nurses employed in geriatric care facilities. Open in-depth interviews were used to collect data from January, 2010 to October, 2010. The Colaizzi phenomenological method was used for data analysis. Results: The experiences of nurses' caring for patients with dementia were divided into the following six categories: 'new encounter', 'understanding of intention and satisfying', 'dilemma of caring', 'contriving of comfort', 'comprehensive coordinator', and 'being present'. There were 15 clusters of themes. The subjects stated that the best caring for the demented older persons were 'encounter, knowing, and being with them'. Conclusion: Nurses' caring could improve the quality of life for demented older patients in geriatric care facility. These results suggest that institutional, administrational strategies and schemes need to cluster around the relationship with patients who would include encounter knowing and being with them.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10a
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• pp.275-277
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• 2000

분산 데이터베이스 시스템에서 데이터의 일치성을 유지하기 위해 원자성 완료 규약을 수행한다. 2PC 규약은 규약 수행시 조정자의 고장으로 인하여 참여자들이 블록킹이 될 수 있다. 참여자들이 블록킹되는 것은 자신들의 자원을 풀지 못하고 조정자가 고장에서 복구될 때까지 기다려야 한다. 블록킹을 해결하기 위해 제안된 방법은 3PC(Three Phase Commit Protocol)규약이 대표적이다. 이 규약은 블록킹은 해결하지만 2PC(Two Phase Commit) 규약보다 많은 메시기 교환과 로그 기록을 하게 되고 따라서 규약을 수행하는 데 걸리는 시간이 증가된다. 본 논문에서는 2PC 규약의 변형으로 블록킹을 해결할 수 있는 기법을 제안하므로써 기존의 3PC 규약보다 수행시간을 향상시킨다. 제안하는 완료규약의 특징은 새로운 조정자를 규약 전에 미리 선출하여 조정자 고장 발생시 종료규약을 수행하게 함으로써 블록킹을 해결하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.973-976
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• 2005

In IEEE 802.15.4 (Low-Rate Wireless Personal Area Network) specification, a successful reception and validation of a data or MAC command frame can be confirmed with an acknowledgment. However, the specification does not support security for acknowledgment frame; the lack of a MAC covering acknowledgments allows an adversary to forge an acknowledgment for any frame. This paper proposes an identity authentication mechanism at the link layer for acknowledgment frame in IEEE 802.15.4 network. With the proposed mechanism there is only three bits for authentication, which can greatly reduce overhead. The encrypted bit stream for identity authentication will be transmitted to device by coordinator within association process. Statistical method indicates that our mechanism is successful in handling MAC layer attack.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.11a
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• pp.643-646
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• 2005

지그비(zigbee) 장비는 센서 네트워크 장비 중에서도 규모가 큰 축에 속하고 배터리로 동작하기 때문에 전력 소비가 큰 문제점으로 부각되고 있다. 지그비에서 비콘(beacon)을 사용하는 네트워크를 구성하면, 센서 장치들은 데이터 전송 빈도가 낮을 때도 중앙 데이터 처리기(coordinator)가 전송하는 비콘 패킷을 매번 받아야 하기 때문에 그에 따른 전력소모가 상당히 높다. 이러한 지그비 네트워크의 중앙 데이터 처리기와 주변 센서 장치(device)에 비콘 수신 주기를 동적으로 설정할 수 있는 프로토콜을 추가 함으로써 기존의 데이터 응답 속도를 유지하면서 전력 소모도 줄이는 방안을 제시하고자 한다.