• Journal of Wetlands Research
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• v.25 no.2
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• pp.132-144
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• 2023

The use of constructed wetlands (CWs) to sequester carbon has been a topic of interest in recent studies. However, CWs have been found to be both carbon sinks and carbon sources, thus leaving uncertainties about their role in carbon neutrality initiatives. To address the uncertainties, a bibliometric and comprehensive review on carbon sequestration in CWs was conducted. Upon forming various scripts using CorText Manager, it was found that a majority of the studies focused on the effectiveness of CWs to remove nutrients, particularly nitrogen. The results of the comprehensive review revealed that high carbon concentrations and carbon sequestration rates in CW soils are dependent on the vegetation types used, the ages of the CWs, and the organic content of inflow water entering the CWs. The Typha genus was the most dominant plant genus used in the CWs from the reviewed studies and was associated with the highest carbon sequestration rates documented in this review study. Furthermore, the relatively high ability of tree species, in comparison to emergent plants, to sequester carbon was observed. Therefore, incorporating tree species into CW designs and adding them to emergent plants is seen as a potential breakthrough approach to improve the ability of CWs to sequester carbon and ultimately contribute to mitigating climate change.

• Industry Promotion Research
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• v.8 no.4
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• pp.37-46
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• 2023

Due to the aging, advancement, and complexity of chemical facilities, non-routine work such as facility inspection, repair, or maintenance work is increasing. Of the 1,483 accidents that occurred over the past 10 years at chemical product manufacturing sites subject to PSM, accidents that occurred during non-routine work accounted for 56% (932 Cases) of the total. It can be seen that more accidents occur during non-routine work than during routine work. In particular, in order to improve the economy and efficiency of factory operation, there are cases where some facilities are stopped without stopping the entire factory and then inspection, repair, or maintenance work is performed while isolated from the operating facilities. Therefore, first, a safe isolation method must be selected by establishing an isolation standard (Baseline Isolation Standard) based on the chemicals handled, operating conditions, and risk level of the equipment in the chemical plant. Second, since current domestic laws and standards do not suggest the need for specific quarantine standards, it is necessary to institutionalize the preparation of quarantine standards. Technical and institutional improvements are needed to prevent fires, explosions, and poisoning accidents caused by leaks of chemical substances.

• Nuclear industry
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• v.5 no.8 s.30
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• pp.69-71
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• 1985

원자력평화이용분야에서 발생하는 방사성폐기물을 어떻게 안전하게 인간환경과 격리시키는가가 원자력개발에 남겨진 큰 문제로서, 각방면에 걸쳐 연구가 예경 진행되고 있다. 다음은 스위스의 방사성폐기물관리공동조합(NAGRA)과 벨기에 원자력연구센터 지하실험장의 개요 소개이다.

• Food Industry
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• s.246
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• pp.2-3
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• 2015

메르스(MERS)는 새로운 변종 코로나바이러스(MERS-CoV) 감염으로 인한 중증급성호흡기질환의 이름이다. 2015년 5월 20일 한국에서 메르스 최초 감염자가 확인되었다. 2015년 6월 17일 기준으로 메르스로 인한 격리대상자는 6,508명이며, 잠복기가 지나 격리가 해제된 사람은 총 3,951명이다. 메르스 광풍에서 살아남을 수 있는 방법은 없을까.

• Journal of the Korean Geotechnical Society
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• v.34 no.1
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• pp.5-16
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• 2018

In this study, seismic performance of geotechnical seismic isolation system capable of primary seismic isolation in the ground was evaluated. 1-G shaking table test was used to assess the performance of Teflon or steel slag as geotechnical seismic isolation systems installed beneath superstructure foundation. Response acceleration and response spectra were analyzed considering different input motions. The results were compared with those of fixed foundation structure without seismic isolation system. The steel slag-type seismic isolation system showed significant reduction in acceleration. The teflon-type seismic isolation system did not show significant effects on acceleration reduction in low-to-moderate seismicity condition, but it did show better effects in case of strong seismic condition. As input motion was transferred to the upper mass, the response spectrum of the fixed foundation structure was amplified in the short period range. In contrast, the response spectrum of the structure with seismic isolation using teflon or steel slag amplified in the long period range. It is found that the change of periodicity and the friction characteristics between isolation materials and foundations affected acceleration reduction.

• The Journal of the Korea Contents Association
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• v.20 no.12
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• pp.646-658
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• 2020

This study assessed the experience of telehealth digital art therapy with a phenomenological case study method based on the need for a psychotherapeutic intervention of caring for the psychological health of self-quarantined people before confirmed with COVID-19. The research participant was a 17-year-old adolescent (girl) from Canada, who participated in seven sessions in a structured telehealth digital art therapy program for 90~120 minutes per session while she was self-quarantining. The analysis of the data was conducted in the process of assessing significant statements through content analysis and drawing themes based on the researcher's pre-understanding and epoche. As a result, 34 themes were drawn, which were classified into 10 common theme clusters and finally into three theses, including "psychology and emotions during self-quarantine", "limitation of remote digital art therapy', and 'positiveness of remote digital art therapy." This study is the case study of telehealth digital art therapy conducted first with a self-quarantined person before confirmed with COVID-19, and at the center of the crisis of COVID-19, hopefully, this study would provide important implications for "psychological quarantine," active self-care for self-quarantined people's psychological health.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.2
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• pp.79-84
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• 2011

In this paper we design MIMO antenna with high isolation between antennas by using an isolation aid for WLAN. Two dual-band PIFAs which operates IEEE 802.11n are arranged symmetrically along the central axis of antenna frame and ground plane. By inserting an isolation aid between two PIFAs the isolation is improved maximum 5dB and 7dB for 2.4GHz band and 5GHz band respectively. Total efficiency is above 60%. ECC is below 0.1.

• Clean Technology
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• v.19 no.3
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• pp.201-211
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• 2013

Biochar is charred materials generated during pyrolysis processes in the absence of oxygen using biomass, resulting in high carbon contents. In recent years, biochar has attracted more increasingly due to its potential role in carbon sequestration, renewable energy, waste management, soil amendment for agricultural use, and environmental remediation. Since biochar has a long-term stability in soil for thousands of years, biochar can be carbon negative compared to carbon-neutral biomass energy that decomposes eventually. Moreover, when biochar is applied to soil, crop production can be largely improved due to its high pH and its superior ability to retain water and nutrients. This paper review the research trends of biochar including the principles of carbon sequestration by biochar, its physico-chemical properties, and its applications on agricultural and environmental area.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.1
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• pp.97-101
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• 2011

Quad band p-HEMT SP6T switch for handset applications was developed. To achieve the low insertion loss and high isolation, trade-off between "On" state and "Off" state was considered by optimization of unit cell. Especially, in case isolation between transmit port and receive port, it was achieved by large capacitors and miniaturization of chip size was achieved by common voltage control and ground using back via process. Designed SP6T switch has size of $950um{\times}100um$ and take into consideration the gate recess error, excellent loss and isolation was confirmed in operating frequency.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.8
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• pp.820-825
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• 2008

A method to improve isolation characteristics of internal MIMO antenna systems for wireless portable devices operating in the $2.3{\sim}2.4$ GHz band is presented. The proposed system incorporates multiple pairs of L-slots between the two antennas in the ground plane, which operate like a band-stop filter, suppressing mutual coupling between the antennas and resulting in improved isolation. A MIMO antenna system with 6 pairs of L-slots shows reflection loss of -26.4 dB and isolation of -37.5 dB.