• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.7
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• pp.261-272
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• 2003

An Ethernet PON(Passive Optical Network) is an economical and efficient access network that has received significant research attention in recent years. A MAC(Media Access Control) protocol of PON , the next generation access network, is based on TDMA(Time Division Multiple Access) basically and can classify this protocol into a fixed length slot assignment method suitable for leased line supporting QoS(Quality of Service) and a variable length slot assignment method suitable for LAN/MAN with the best effort. For analyzing the performance of these protocols, we design an Ethernet PON model using OPNET tool. To establish the maximum efficiency of a network, we verify a MAC protocol and determine the optimal number of ONUs(Optical Network Unit) that can be accepted by one OLT(Optical Line Terminal) and propose the suitable buffer size of ONU based on analyzing the end-to-end Ethernet delay, queuing delay, throughput, and utilization.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.28 no.4
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• pp.261-268
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• 2017

In this paper, we propose an FSSH(Folded Slot Spherical Helix) magnetic dipole antenna with a form factor easy to build and study its radiation properties. The number of folded arms, the gap between them and the metal thickness are tuned to achieve relatively simple structure to realize whereas maintaining high radiation efficiency at an electrically small size. The proposed design shows wide radiation efficiency bandwidth and it is confirmed by circuit simulation that the non-Foster impedance matching techniques could be utilized for its practical use. The prototype of the proposed antenna is built with the aid of an SLS(Selective Laser Sintering) 3D printing technology. The measured result shows lower Q impedance characteristic due to high resistive loss of the copper tape joints.

• Architectural research
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• v.15 no.2
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• pp.59-68
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• 2013

To ameliorate a long-standing, persistent housing shortage in Korea, large-scale massive housing production has been an imperative, and the extensive growth highly values development and consumption. The state's priority for the quantitative growth of housing stock has proved to be successful, but the state faces with economic and environmental crises in a global era. To achieve the qualitative growth, the previous administration pronounced a green growth policy from the inception, and a series of strategic measures under a holistic plan have been taken widely and vigorously. As part of the strategies, the green home project was undertaken, and simultaneously the movement of green living led by the governance has been activated. However, little attention to the grassroots effort was paid and the efficacy hasn't been adequately addressed. This study examines the factors affecting green living of residents in multifamily housing. Based on public guidelines to green living, 106 specific items were drawn out and largely categorized into 6 areas (water, waste, transportation, air quality, consumption, and energy), and the questionnaire was constructed using them. Of 750 survey forms mailed out, 161 responses were returned and the collected data were used for statistical analysis. The findings indicated that varying degrees of green living was well practiced, the state-led green home project was relatively well recognized, and the green growth policy was strongly supported. Also the respondents' attitude toward green living were more associated with demographic variables than housing characteristics, and familiarity with green home project was related to attitudes toward green living. Since the on-going approach to green living has focused on simple and economical ways, it has proved to be effective but progressive strategies to make living greener are necessarily developed.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.2
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• pp.217-221
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• 2012

As a part of basic research to improve screen quality, which deteriorates when strain occurs within optical sheets in LCD modules for laptop computers, a measurement system is needed to analyze the influence of heat and moisture, which are the main factors causing the strain. It is assumed that the existence of an air gap less of than 0.5 mm inside the LCD module causes humid air from outside to permeate through the module. To investigate this phenomenon, in this study a thin printed circuit board (PCB) of compact sensors that measure temperature and humidity is inserted into LCD modules, and thus, the changes in temperature and humidity can be analyzed in real time. The results can be used as basic data for simulation of the deformation behavior and structural design of LCD modules in the future.

• Journal of Korean Academy of Nursing
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• v.41 no.1
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• pp.18-25
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• 2011

Purpose: This study was done to examine the effect of an integrated care service which included a combination of oriental and western care on health outcomes in elderly patients with degenerative arthritis. Methods: A prospective comparative design was used. Data were collected from May 1, 2008 to June 30, 2009 from 85 elderly patients with degenerative arthritis in the lower extremities who were followed in a hospital out-patient department for 8 weeks. The integrated care service group (n=36) received a combination of physical therapy, acupuncture, western medicines or herbal medicines, and the western care group (n=49) received physical therapy or western medicines. Functional independence, walking speed, rotation balance, pain intensity, service satisfaction and total medical costs for the two groups were compared at 8 weeks. Results: Functional independence (t=2.14, p=.036) and walking speed (t=2.51, p=.014) improved significantly in the integrated care group while pain intensity improved significantly in the western care group (t=3.35, p=.002). The integrated care group reported higher scores for service satisfaction (t=2.09, p=.041) and higher medical costs than the western care group (t=2.15, p=.035). Conclusion: The results suggest that integrated care services are effective modalities to improve mobility and quality of life for elders with degenerative arthritis.

• Journal of the Korean Society for information Management
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• v.29 no.1
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• pp.351-374
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• 2012

Recently, the website of university archives is becoming greatly significant to users who retrieve and utilize university archives and records. This study aims to meta-analyze university archives in Korea in terms of usefulness, usability, information quality, and web accessibility in order to improve the functionality and usefulness of university archives websites. The result of the study suggests that university archives should increase the number of the digital records and to develop communication chanels, such as blog, chatting room, digital reference services for activating use of university records. Secondly, university archives make efforts to develop systematic collecting and managing procedures and to build relevant digital collections. Thirdly, the websites of university archives develops more user-friendly interfaces and web design to improve user satisfaction. Finally, the websties of university archives should follow the standards on web accessibility.

• Journal of Fashion Business
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• v.12 no.2
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• pp.117-133
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• 2008

In this research, female adults in ages 25 to 34 that reside in Shanghai, China, have been polled from 29th of December, 2007 to 2nd of February, 2008 in accordance with simple random sampling method. 210 women have been selected and polled. Of these, 10 who responded in appropriately were excluded and the remaining 200 were used in the final analysis. The questionnaires used in this poll were made up of ones that are about how they wear tailored suits and how much they are satisfied with them, and questions about demographical characteristics. SPSSWIN 12.0 Program was used as the analysis method in getting statistics and descriptive statistical analysis, t-test, and $x^2$ analysis have been performed. The summary about the Chinese female adults is as follows: 1. They prefer jackets with design, style, and quality that better fit them to the ones with a name brand and a lower price. 2. They prefer shoulder princess style jackets with short lapel color lengths and slacks with a basic style in waistline. 3. When wearing jackets they feel uncomfortable in all regions and were not satisfied. 4. All responded that they have an experience of having the jackets mended after purchasing them and a high frequency of mending was shown along the waistline, hips, and leg lengths.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2364-2369
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• 2015

In this paper, the optimum RPM was suggested comparing rotor filling rate of RPM through the analysis of rotor's filling rate as studying and developing centrifugal-casting machine's method for high precision rotor in order to increase the related types of business's productivity. The result was similar to other result in industrial site, showing 99.47% of filling rate when rotational speeds are 600 rpm, so it is considered that if this result is conducted with additional research, it will be possible to plan a better process design. Besides, the optimum temperature of compact ladle was examined to produce high quality casting product through the analysis of compact ladle's conductivity. In the case of the heating device's absence using nicrome wire, Al solution solidifies falling drastically into $427^{\circ}C$. However, it is feasible to work over $427^{\circ}C$ which is the melting temperature of aluminium solution when the heating device of nicrome wire is included. It reveals that there is little temperature change.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1251-1264
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• 2002

Currently, audio streaming services such as on-demand service and live service support only a limited number of clients. They also suffer from a lack of stability and degradation of service quality due to their inefficient use of network resources. Futhermore, since the streaming services usually do not consider dynamic services, they are very inconvenience to use. In order to resolve these drawbacks, we propose a novel audio streaming system based on MPEG-2 AAC file format which are facilitated with the network bandwidths efficiently. The proposed system supports QoS for audio streaming as well as guarantees a stability while streaming service is undergoing. Moreover, the system provides a dynamic interface which enables us to use the streaming service more easily and to manage streaming servers with convenient manner. On the contrary, most of the current available static interface streaming services are mainly depending only on a single fixed web page between client and server, which in consequence lead us to use unflexible static service environment. Our implementation results show the proposed system improves the performance compared to those of the currently existing systems that use MP3 file format. It also provides some benefits such as a stability of service and a easy to management of streaming servers.

• Journal of the Korean Data and Information Science Society
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• v.26 no.2
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• pp.441-453
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• 2015

This paper review nursing performance in Korea to suggest the direction of future research. A literature review of research nursing performance journal articles was performed. Thirty-three articles were analyzed research design, measurement tools, definition, and variables which with nursing performance. Most of the on nursing performance in Korea descriptive correlation study. There considerable confusion about Korean term and definitions nursing performance. used the instrument developed by Park (1989) to measure nursing performance. The variables with nursing performance leadership and empowerment. No agreement on definitions or concepts of nursing performance evident in Korea. Research on nursing performance that addresses all domains of nursing is needed to analyze the impact of nursing performance on patient and healthcare outcomes.