• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.10
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• pp.1744-1750
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• 2007

This paper addresses grid interconnection tests of a 3kW transformer-less photovoltaic (PV) inverter to verify the effectiveness of the PV inverter and promote its wide use. The 3kW transformer-less PV inverter, which was equipped with intelligent protection and control system, was manufactured. A hardware test bed was constructed for performance tests of the PV inverter. Control performance and grid protection tests were carried out using the test bed. Test results verify the performance of the power control and grid protection functions of the developed transformer-less PV inverter.

• Journal of Communications and Networks
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• v.9 no.2
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• pp.167-176
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• 2007

In multimedia communication systems, efficient transmission system design should incorporate the use of matching unequal error protection (UEP), since source coders exhibit unequal bit error sensitivity. In this paper, we present UEP schemes which exploit differences in bit error protection levels in orthogonal frequency division multiplexing (OFDM) systems over frequency selective fading channels. We introduce an UEP scheme which improves the link performance with multiple transmit and receive antennas. Especially, we propose a new receiver structure based on two stage Maximum Likelihood detection (MLD) schemes which can approach the performance of a full search MLD receiver with much reduced computational complexity. In the performance analysis, we derive a generalized pairwise error probability expression for the proposed UEP schemes. Simulation results show that the proposed schemes achieve a significant performance gain over the conventional equal error protection (EEP) scheme.

• KIEE International Transactions on Power Engineering
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• v.5A no.2
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• pp.103-108
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• 2005

Catastrophic failures in power systems are rare but not uncommon events. Protection systems play an important role in the progression of events during a catastrophic failure. This paper will examine some of the historical records, and suggest possible improvements to protection systems which can have a positive impact on power system performance during catastrophic failures.

• Journal of the Korean Society of Clothing and Textiles
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• v.42 no.4
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• pp.612-625
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• 2018

This study designed 16 kinds of basic structure and 4 kinds of modified structure for impact protection pads with a spacer fabric shape. The pad is a structure in which hexagonal three-dimensional units, composed of a surface layer and a spacer layer, are interconnected. Designed pads were printed with flexible $NinjaFlex^{(R)}$ materials using a FDM 3D printer. The printed pads were evaluated for impact protection performance, compression properties and sensory properties. The evaluation of the impact protection performance indicated that basic structures better than CR foam material at 20cm height were DV1.5, DX1.5, DX1.0, DV1.0 and HV1.5. The evaluation of the compression properties for the five types, with good results in the impact protection performance, indicated that DV1.0, DX1.0, DV1.5, HV1.5 and DX1.5 showed good results, respectively. The sensory evaluation of DV1.0, DX1.0, and DV1.5, which with good results when considering both the impact protection performance and the compression performance, showed that DV1.0 were the best for surface, flexibility, compression and weight. Therefore, DV1.0 is shown to be the best structure for protection pads.

• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.102-107
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• 2004

Performance based design is a recent evolutionary step in the process of designing fire protection systems. In essence, it is a logical design process resulting in a solution that achieves a specified performance. Sometimes the prescriptive solutions presented in various codes and standards are too expensive or inflexible. Often the solutions do not and enables optimization of a solution for cost and function. In this study, performance based design was carried out to determine the extent of passive fire protection for oil terminal facilities. The results of performance based design were compared with those of prescriptive code based design. Performance based design is not always more economic than prescriptive code based design but provides more reliable and effective design that is fit for the purpose.

• International Journal of Advanced Culture Technology
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• v.8 no.4
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• pp.101-109
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• 2020

Along with rapid global economic development, people are slowly becoming environmentally aware and green development is increasingly a vital topic of social concern. Academic circles are currently focusing on environmental protection and economic growth to explore the coordinated development of both and to achieve a win-win solution between them. To study the relationship between environmental protection experience and both cost and performance, this study empirically analyzes companies listing on the Shenzhen A-share market from 2014 to 2018. The results show that senior executives' environmental protection experience is negatively correlated with corporate costs, whereas it is positively correlated with business performance. These results provide empirical evidence of the importance of enterprises introducing and cultivating environmental personnel and insisting on sustainable development.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.1
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• pp.49-61
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• 2015

This is the second of two companion papers that describe the performance assessment for flexible rockfall protection systems. Described in a companion paper is the criteria to assess the performance of flexible rockfall protection systems. In this study the performance assessment of domestic rockfall protection fences was implemented using the criteria suggested in the companion paper. It was investigated that the rockfall protection fences for express highways performed well to resist the rockfall energy of 50kJ and the deformed rockfall protection fences right after impacting would not obstruct the vehicle traffic. However, to dissipate the rockfall energy of 50kJ with the level of European standards constantly, the spacing of wireropes was adjusted to be 200mm up to the 8th wirerope from the bottom and spacing-maintainers should be extended to the 8th wirerope. It was figured out that the rockfall protection fences for general highways were required to install spacing-maintainers as those for express highways because they, which did not have spacing-maintenance members, were very prone to the penetration of rockfall even for the very small rockfall impact energies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.2
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• pp.416-426
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• 2016

This study intended to identify dental hygienists' knowledge and extent of awareness and performance of patient's personal information protection. In addition, this research was conducted to contribute to medical centers' preparation of measures to strengthen the personal information protection by identifying the factors affecting dental hygienists' extent of performance related to the patient's personal information protection. After explaining the purpose and meaning of the research to the survey participants and gaining their consent, a self-administered survey was conducted from November 7, 2014 to June 30, 2015. The data on 210 dental hygienists in Busan city and Gyeongsangnam-do province was used for analysis. As a result, in dental hygienists with more than 10 years experience, the extent of the performance was significantly high (p<.05). In positions higher than a senior manager, the extent of knowledge was high (p<.01) and the extent of performance was significantly high (p<.05). In hospitals with more than 10 to 20 workers, the extent of awareness was significantly high (p<.05). Regarding the correlation of knowledge and the extent of awareness and performance, a high level of knowledge showed a positive correlation of the extent of awareness and performance (p<.01). As a result of a survey regarding what effects dental hygienists' knowledge and extent of awareness of patient's personal information protection have on dental hygienists' extent of performance, it was found that knowledge (.231) and the extent of awareness (.212) are factors affecting the extent of performance. Therefore, to increase the extent of dental hygienists' performance of patient's personal information protection, there is a need to improve the knowledge of patient's personal information protection and change its awareness. To change the awareness of patient's personal information protection, there is a serious need to carry out education targeting dental hygienists.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.1
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• pp.75-80
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• 2012

The integrated protection unit of CHEONGUNG is composed of chemical-biological equipment and air conditioner equiped heating element. The protection capabilities against chemical-biological agent were measured by using simulant agents such as n-Hexane, KM5 Screening Smokes and CS agent. The experimental test results with simulant agents verify the protective performance of the integrated protection unit.

• Fire Science and Engineering
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• v.24 no.2
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• pp.126-132
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• 2010

The Housing Performance Rating System, enacted on 9 January 2006, an active measure containing provisions on improved quality and advanced performance of the Fire-Protection System for equalized ability to secure safety of life to some extent, is a desirable policy in fire-safety regard. The study of theoretical background of each performance rating section for the purpose of active and wide application of The Fire-Protection System category of the Housing Performance Rating System currently in effect internally. In accordance with the result of the study, the reform measures for the currently detailed evaluation criteria have been suggested to improve the performance of the Fire-Protection area of The Housing Performance Rating System currently being in force based on the assumption of prior settlement of the following; upward settlement of the point distribution standards on the performance ratings of each head backed up by an institutional Government policy with overriding priority; and urgently enacted Fire-Protection related laws and regulations.