• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.21-26
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• 2007

최근 이동체의 위치 데이타를 활용한 위치 기반 서비스에 대한 관심이 높아지면서, 보다 효율적인 이동체 위치 데이타 관리 시스템으로 클러스터 기반 분산 컴퓨팅 구조인 GALIS(Gracefully Aging Location Information System)가 제시되었다. 그러나 GALIS의 서브 시스템인 SLDS(Short-term Location Data Subsystem)는 다수의 SDP(Short-term Data Processor) 노드들이 처리한 질의 결과를 SDP 마스터에서 취합하여 클라이언트로 보내는 구조이기 때문에 SDP 마스터에 장애가 발생할 경우 서비스가 중지되고, SDP 마스터에 부하가 집중될 경우 클라이언트로의 응답 시간이 길어지는 문제가 있다. 따라서, 본 논문에서는 기존 SLDS에 이중화를 지원하기 위해 SDP 마스터를 추가하여 기존 SLDS의 안정성을 높이고 이동체 위치 데이타의 질의 처리 성능을 향상시킨 확장 SLDS를 설계 및 구현하였다. 확장 SLDS에서는 두 대의 SDP 마스터를 가동함으로써 한 SDP 마스터에 장애가 발생하더라도 다른 SDP 마스터가 서비스를 계속 제공함으로써 시스템의 안정성을 보장한다. 또한, 확장 SLDS는 두 대의 SDP 마스터가 질의 처리를 분산하여 수행하기 때문에 클라이언트로의 응답 시간을 줄일 수 있다. 마지막으로 확장 SLDS의 장애 테스트와 질의 처리 성능을 실험하였으며, 이러한 실험을 통해 확장 SLDS의 고신뢰성 및 고가용성을 검증하였다.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.8
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• pp.119-125
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• 2009

Fabrication of a three-dimensional (3D) metallic mold for multi-production of a microstructure was studied to settle the problem of long processing time in 3D microfabrication. To date, complicated 3D microstructures including 3D photonic crystals, 3D microlens array, 3D filter for microfludics, and something else were created successfully using the two-photon polymerization (TPP) which was considered as paving the way to fabricate a real 3D shape in nano/microscale. However, for those fabrications, much processing time and efforts were inevitably required. To solve this issue, a simple and effective way was proposed in this paper; 3D master patterns were prepared using TPP, and then counter-shaped Ni molds were fabricated by electroforming process. By using these molds, 3D microstructures can be reproduced with short-processing time and low-effort comparing to the conventional approach, TPP We report some parameters to fabricate a metallic mold precisely.

• Journal of Computing Science and Engineering
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• v.11 no.3
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• pp.92-99
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• 2017

Memcached, commonly used to speed up the data access in big-data and Internet-web applications, is a system software of the distributed-cache mechanism. But it is subject to the severe challenge of the loss of recently uncommitted updates in the case where the Memcached servers crash due to some reason. Although the replica scheme and the disk-log-based replay mechanism have been proposed to overcome this problem, they generate either the overhead of the replica synchronization or the persistent-storage overhead that is caused by flushing related logs. This paper proposes a scheme of backing up the write requests (i.e., set and add) on the Memcached client side, to reduce the overhead resulting from the making of disk-log records or performing the replica consistency. If the Memcached server fails, a timestamp-based recovery mechanism is then introduced to replay the write requests (buffered by relevant clients), for regaining the lost-data updates on the rebooted Memcached server, thereby meeting the data-consistency requirement. More importantly, compared with the mechanism of logging the write requests to the persistent storage of the master server and the server-replication scheme, the newly proposed approach of backing up the logs on the client side can greatly decrease the time overhead by up to 116.8% when processing the write workloads.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.05a
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• pp.513-516
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• 2008

We have replicated nanopillar arrays using injection molding process of active heating and cooling method by several peltier devices. The injection melding has a high accuracy ed good reproducibility that are essential for mass production at low cost. Conventional molding processes widely use the water-based mold heating and air cooling methods. However, in case of replication for nano-patterned structures, it caused several defects such as air-flow mark, non-fill, sticking and tearing. In this study, periodic nano-scale patterns are replicated by using injection molding with Peltier devices. Porous nano-scale patterns, which have pore diameter range from 120nm to 150nm, were fabricated by using anodizing process. Periodic nano-pore structures ( $20mm\;{\times}\;20mm$) were used as a mold stamp of injection molding. Finally, PMMA with nanopillar arrays was obtained by injection molding process. By using the Peltier devices, the temperature of locally adiabatic molds can be dramatically controlled and the quality of the molded patterns can be slightly improved.

• Journal of Korean Academy of Nursing
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• v.28 no.3
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• pp.786-800
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• 1998

The purposes of this study were to describe systemically 18 years of oncology nursing research in Korea and suggest it's direction in future. 149 nursing studies published from 1980 to 1998 were selected for the present study. There were examined the source and the design of study, type of subjects, measurement variables, the intervention outcome of experimental research, and theme of qualitative research. The results were as follows : 1. 121 of 149 studies were composed of master thesis and dissertation of graduate school. There were 55 correlations, 30 descriptions, 19 comparisons, 19 qualitative studies and 2 Q-methods as the type of research design. 2. Cancer patients without describing specified diagnosis as subjects' characteristic were 44 of total studies. The others had various diagnoses such as gastric cancer, uterine cancer, breast cancer, leukemia, lymphoma, colorectal cancer, and lung cancer. According to treatment type, patients receiving chemotherapy were the highest number distribution as 53 of all researches. 3. Most measurement instruments used for research were translated it into Korean that developed by foreigners, such as Zung's depression, Spielberg's anxiety, and Wallston's locus of control. 4. Quality of life was shown the most frequently among correlational researches. the next one was depression, the third was hope, and so on. 5. There was the most frequent comparison between cancer and non-cancer patients in comparative researches. It was surveyed those variables as diet habits, risk factors, stressful life events, anxiety and depression, and self-care capacity between two groups. 6. The subjects were mostly chemotherapy patients as 15 of 24 experimental studies. Oral care and education were respectively the highest experimental interventions. 7. Qualitative researches about cancer were reported since 1991. Their themes were illness experience, adaptation process, dying experience, family experience, hope, caring, experience of health behavior, meaning of chemotherapy and experience of cancer survivor. Phenomenologic methodology was designed above 50% of qualitative researches. According to the above findings, cancer research had increased since 1990 and done mostly by descriptive design but a few experimental studies. As recommendations for the future, It is necessary to study the comparison of oncology nursing research internationally, the replication to establish the effect of nursing intervention, and the family care of cancer patient.

• The Journal of the Korea Contents Association
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• v.12 no.12
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• pp.119-125
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• 2012

It is not an overstatement to say that the functions of the products change and the results determine the size and weight of the product. It took a long time to develop the small size everyday tools. One of the ways to shorten the development time was the emergence of vacuum moulds that decreased the design process significantly. In other words, the manufacturing of the product may be limited by the size and shape, but the replication of a simple structure is possible within a few hours. This study aims to review and suggest the design development through vacuum moulds as an area to realize the future additional values to the economic growth under the rapidly changing industry structures as well as securing the weaknesses of the industry structures through the productivity and competitiveness of the corporations.

• The Korean Journal of Rehabilitation Nursing
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• v.3 no.2
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• pp.154-168
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• 2000

This study was done to analyze the trends of research on stroke in Korea, to suggest future direction, for research on stroke. This article reviewed 75 nursing research papers on stroke done since 1990 to 2000 by examining them according to the period of publication or presentation, research design, type of subjects, measurement variables, the intervention outcome of experimental research, and theme of qualitative research. The research were as follows : 1. 26 of 75 studies were composed of master thesis and dissertation of graduate school. There were 53 nonexperimental research, 15 experimental research, and 7 qualitative studies design. 2. Stroke patients subject' Characteristic were 44 and Family and Spouses of caregiver support were 28 of total studies. 3. Most measurement instruments used for research were translated and redesigned it into Korean that developed by foreigners, and development measurement instruments used Kang's ADL. 4. Family support and Social support was shown the frequently among correlational research. 5. Methodological research were development of an evaluation tool for the quality of nursing care in stroke patients, caregiver support of development of nursing intervention list, and Home care Nursing Intervention protocol, and development of client selection criteria based on the needs of services to be offered. 6. The experimental research of intervention were mostly education nursing intervention, rehabilitation program on functional recovery, support nursing intervention, and applying a home care protocol on the nursing care intervention. 7. Theme of qualitative research were family experience, home care in family experience, soobal experience, illness experience, hope of Stroke patients and so on. Phenomenologic methodology and Granded Theory was designed of Qualitative research. On the basis of the above finding the following recommendations are made: 1. It's necessary to develop a reliable and variable measurement tool for stroke patients and family care of stroke patients. 2. It's necessary to study the comparison of Nursing Studies of stroke research abroad, the replication to establish the effect of nursing intervention stroke patients and family care of stroke patients.