• 디자인학연구
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• 제17권3호
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• pp.393-402
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• 2004

프뢰벨이 1837에 창안한 은물(Gifts)은 유아교구에서 구체적이고 체계적인 놀이감을 이용한 최초의 교수매체였다. 프뢰벨이 은물의 형태에서 제시하고 있는 육면체, 원기둥, 구의 형태와 점선면의 개념, 그리고 6개 색채 등의 조형적 개념은 근대디자인에서 시각적 조형요소의 기초를 이루게 된다. 그러나 프뢰벨 유아교육사상을 현실적으로 교육현장에 적용하기 위하여 제시된 교육적 놀이감인 은물교구에 대한 디자인적 고찰과 분석은 거의 이루어지고 있지 않은 실정이다. 본 연구에서는 프뢰벨 은물에 대한 시각적 조형성을 분석하여 봄으로써 프뢰벨 교육사상이 은물의 조형적인 형태생성에 끼친 구조적 원리를 고찰하고자 한다. 따라서 은물이 가지고 있는 조형원리에 대한 분석을 통하여 추상적이고 철학적인 사상체계가 시각적으로 어떻게 형태에 적용되었는지를 연구하였다. 본 연구는 은물교구에서 제시되고 있는 조형성에 대한 탐색적 고찰로서, 기하조형에 대한 형태생성원리의 연구이며, 그에 대한 영향력과 유아교구의 조형성에 대한 문제점을 디자인적 시각에서 분석하여 본 것이다.

• Journal of the Korean Institute of Landscape Architecture International Edition
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• 제2호
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• pp.185-191
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• 2004

This study dealt with the Kogi River, located in Kaizuka City, Osaka, which has experienced different improvements from the upper through the lower regions, aimed at revealing temporal relations between residents and the river, as well as probing future problems and directions regarding the river in the suburban area, by conducting a survey of local residents. The result showed that, in the upper region where nature remains in its natural state and the good water quality has been maintained, the relations between the residents and the river continued until around 1965; meanwhile in the middle region the relations have been disappearing since about 1955, and in the lower region where the stream has been repeatedly rehabilitated since 1955, there are fewer involvements of the people with the river. It also revealed that the weaker the relations between people and the river became, the larger the number of residents, even in the upper region, who became concerned over the deteriorating river environment after about 1975, and that in the middle and lower areas, about a decade earlier than in the upper area, the number of those who were aware of the environmental deterioration began to increase. Consequently, with an eye to resuming the relations between people and the river in an suburban area, their future challenges would be the space improvements depending on the environmental characteristics of the area; for example, the recovery of grassy banks for the purpose of protection in the lower region; the preservation and maintenance of many waterside woods as well as the creation of open spaces utilizing the river banks in the middle area; and throughout the whole region, the establishment of a system in which the relations between man and the river can be passed down to future generations, by utilizing the local human resources including those who know the former river landscapes or about the playing in and around the river.

• 폴리머
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• 제31권2호
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• pp.123-129
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• 2007

세 종류의 폴리올레핀 복합재료의 기계적인 특성과 파괴인성 메커니즘이 연구되었다. 기계적 특성을 조사하기 위해 인장 시험 및 아이조드 충격 시험이 수행되었다. 균열 선단 주위의 파손 메커니즘을 정확히 조사하기 위해 2노치-4점 굽힘 기법이 도입/적용되었다. 광학현미경과 투과형 전자현미경을 이용하여, 폴리올레핀 복합재료의 균열 선단 주변 국부적인 파괴인성 특성들이 관찰되었다. 이를 통한 구체적인 관찰은, 폴리올레핀 복합재료의 균열선단 주변에 전단밴딩, 크레이즈, 입자-수지간 분리, 고무입자의 캐비테이션, 크랙 휭 및 크랙 분기 등과 같은 다양한 파괴인성 메커니즘들이 존재함을 보여주었다. 이러한 파괴인성 메커니즘들은 아이조드 충격 시험에서 보여진 파괴인성 값의 증가에 대한 실질적인 원인으로 보여진다. 본 연구를 바탕으로, 2노치-4점 굽힘 기법은 폴리올레핀 복합재료의 파괴 거동과 그와 관련된 파괴인성 메커니즘을 기술할 수 있는 충분한 정보를 제공하였다.

• Safety and Health at Work
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• 제9권3호
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• pp.265-276
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• 2018

Background: Resilience engineering is a paradigm for safety management that focuses on coping with complexity to achieve success, even considering several conflicting goals. Modern sociotechnical systems have to be resilient to comply with the variability of everyday activities, the tight-coupled and under-specified nature of work, and the nonlinear interactions among agents. At organizational level, resilience can be described as a combination of four cornerstones: monitoring, responding, learning, and anticipating. Methods: Starting from these four categories, this article aims at defining a semiquantitative analytic framework to measure organizational resilience in complex sociotechnical systems, combining the resilience analysis grid and the analytic hierarchy process. Results: This article presents an approach for defining resilience abilities of an organization, creating a structured domain-dependent framework to define a resilience profile at different levels of abstraction, and identifying weaknesses and strengths of the system and potential actions to increase system's adaptive capacity. An illustrative example in an anesthesia department clarifies the outcomes of the approach. Conclusion: The outcome of the resilience analysis grid, i.e., a weighed set of probing questions, can be used in different domains, as a support tool in a wider Safety-II oriented managerial action to bring safety management into the core business of the organization.

• Journal of Photoscience
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• 제11권3호
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• pp.133-139
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• 2004

The metal-ligand complex, $[Ru(phen)_2(dppz)]^{2+}$ (phen=1,10-phenanthroline, dppz=dipyrido[3,2-a:2',3'-c]phenazine) (RuPD), was used as a spectroscopic probe for studying nucleic acid dynamics. The RuPD complex displays a long lifetime and a molecular light switch property upon DNA binding due to shielding of its dppz ligand from water. To show the usefulness of this luminophore (RuPD) for probing nucleic acid dynamics, we compared its intensity and anisotropy decays when intercalated into the $tRNA^{val}$ and pBluescript (pBS) II SK(+) phagemid through a comparison with ethidium bromide (EB), a conventional nucleic acid probe. We used frequency-domain fluorometry with a blue light-emitting diode (LED) as the modulated light source. The mean lifetime for the $tRNA^{val}$ (<${\tau}$> = 166.5 ns) was much shorter than that for the pBS II SK(+) phagemid (<${\tau}$> = 481.3 ns), suggesting a much more efficient shielding from water by the phagemid. Because of their size difference, the anisotropy decay data showed a much shorter rotational correlation times for the $tRNA^{val}$ (99.9 and 23.6 ns) than for the pBS II SK(+) phagemid (968.7 and 39.5 ns). These results indicate that RuPD can be useful for studying nucleic acid dynamics.

• Journal of Dental Anesthesia and Pain Medicine
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• 제19권2호
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• pp.101-109
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• 2019

Background: The purpose of this study was to compare the pain perception and anesthetic efficacy of 2% lignocaine with 1:200,000 epinephrine, buffered lignocaine, and 4% articaine with 1:200,000 epinephrine for the inferior alveolar nerve block. Methods: This was a double-blind crossover study involving 48 children aged 5-10 years, who received three inferior alveolar nerve block injections in three appointments scheduled one week apart from the next. Pain on injection was assessed using the Wong-Baker Faces pain scale and the sound eye motor scale (SEM). Efficacy of anesthesia was assessed by subjective (tingling or numbness of the lip, tongue, and corner of mouth) and objective signs (pain on probing). Results: Pain perception on injection assessed with Wong-Baker scale was significantly different between buffered lignocaine and lignocaine (P < 0.001) and between buffered lignocaine and articaine (P = 0.041). The onset of anesthesia was lowest for buffered lignocaine, with a statistically significant difference between buffered lignocaine and lignocaine (P < 0.001). Moreover, the efficacy of local analgesia assessed using objective signs was significantly different between buffered lignocaine and lignocaine (P < 0.001) and between lignocaine and articaine. Conclusion: Buffered lignocaine was the least painful and the most efficacious anesthetic agent during the inferior alveolar nerve block injection in 5-10-year-old patients.

• 한국전자파학회논문지
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• 제29권12호
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• pp.915-923
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• 2018

본 논문은 ISM 대역인 902~928 MHz에서 건물의 내구성을 진단하기 위한 콘크리트 매립형 안테나 설계에 관하여 서술한다. 이에 안테나가 매립되는 환경에서도 콘크리트 매질 특성에 의해 임피던스 변화가 크지 않는 이중 슬롯 패치 안테나를 제안하였다. 함수율에 따라 변하는 콘크리트 매질에 의한 성능 열화를 최소화하기 위해 제안하는 안테나는 기생 패치를 이용하여 대역폭을 확장하였다. 제작된 안테나는 전 대역에서 VSWR 2 : 1 이하 특성을 만족하며, 빔 폭은 80도 정도이며, 7 dBi 이상을 만족하는 이득을 가진다. 제안한 안테나는 직사각형 콘크리트 블록에 장착하여 측정하였으며, 모의실험과 실제 측정을 통해 함수율 변화에 따른 반사손실 및 이득을 확인하였다.

• Journal of Periodontal and Implant Science
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• 제49권2호
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• pp.60-75
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• 2019

The primary aim of this systematic review was to assess the evidence on periodontal disease progression after treatment in patients receiving supportive periodontal therapy (SPT) and to identify predictors of clinical attachment level (CAL) loss. A protocol was developed to answer the following focused question: In adult patients treated for periodontitis, what is the disease progression in terms of CAL loss after surgical or non-surgical treatment? Randomized controlled clinical trials, prospective cohort studies, and longitudinal observational human studies with a minimum of 5 years of follow-up after surgical or non-surgical treatment that reported CAL and probing depth changes were selected. Seventeen publications reporting data from 14 investigations were included. Data from 964 patients with a follow-up range of 5-15 years was evaluated. When the CAL at the latest follow-up was compared to the CAL after active periodontal therapy, 10 of the included studies reported an overall mean CAL loss of ${\leq}0.5mm$, 3 studies reported a mean CAL loss of 0.5-1 mm, and 4 studies reported a mean CAL loss of >1 mm. Based on 7 publications, the percentage of sites showing a CAL loss of ${\geq}2mm$ varied from 3% to 20%, and a high percentage of sites with CAL loss was associated with poor oral hygiene, smoking, and poor compliance with SPT. The outcomes after periodontal therapy remained stable over time. Disease progression occurred in a reduced number of sites and patients, mostly associated with poor oral hygiene, poor compliance with SPT, and smoking.

• Journal of Periodontal and Implant Science
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• 제49권2호
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• pp.105-113
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• 2019

Purpose: An unresolved inflammatory state contributes to the pathogenesis of periodontal disease and metabolic syndrome (MetS). Therefore, the purpose of this study was to evaluate the role of lipoxin A4 (LXA4), a proresolving lipid mediator, in the association between periodontal disease and MetS. Methods: Sixty-seven patients with MetS and 65 patients without MetS were included in the study. Sociodemographic information was obtained via a questionnaire, and detailed medical diagnoses were made. Periodontal parameters (plaque index [PI], gingival index [GI], probing pocket depth [PD], and clinical attachment level [CAL]) and metabolic parameters were measured, and serum LXA4 levels were determined. The associations among MetS, periodontal parameters, and serum LX levels were evaluated by adjusted multivariate linear regression analyses. Results: Patients with MetS were older and had a higher body mass index than patients without MetS. Periodontal parameters (PI, GI, PD, and CAL) were higher in patients with MetS than in those without MetS. Serum LXA4 levels were higher in patients without MetS. Multivariate linear regression analysis indicated a positive association between MetS and periodontal parameters (PD and CAL). Negative associations were established between MetS and LXA4 levels, and between LXA4 and periodontal parameters (PI, PD, and CAL). Conclusions: The presence of higher values of periodontal parameters in patients with MetS and the negative relationship of LXA4 with MetS and periodontal disease may support the protective role of proresolving lipid mediators in the association between periodontal disease and MetS.

• 천문학회보
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• 제44권1호
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• pp.36.3-36.3
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• 2019

Feedback process is one of the most important topics in the study of AGNs since it plays a key role in linking the SMBHs and their host galaxies. In order to further understand the co-evolution of SMBHs and their host galaxies, we probe the feedback process in local type-2 AGNs with a series of integral-field-spectroscopy observations. In the first part of my talk, I will introduce our GMOS observations of luminous type-2 AGNs at z < 0.1, which are selected using the integrated [O III] kinematics. Based on the dedicated emission-line diagnostics and kinematic studies, we identify the signatures of AGN-driven outflows and quantify the outflow size in the targets with extreme [O III] kinematics. For the targets without extreme [O III] kinematics, we find the presence of weak AGN-driven outflows, which are indicated by the significant differences between the kinematics of gas and stars. Then, I will present our recent study of 40 type-2 AGNs based on the SNIFS IFU. By comparing the radial profile of velocity dispersion of gas and stars, we measure the size of AGN-driven outflows in these targets and extend the outflow size-AGN luminosity relation in our previous GMOS studies. We also discuss the feedback effect of AGN-driven outflows by connecting the outflow velocity and host galaxy properties. These results highlight the importance of spatially-resolved observation in investigating gas kinematics and identifying the signatures of AGN-driven outflows.