• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1995년도 추계학술대회 논문집
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• pp.217-220
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• 1995

By substituting Cd$\^$2+/ into both A-site and B-site in PNN-PZ-PT ternary perovskite material, it is possible to determine the effects of the substitution site of Cd$\^$2+/ on sintering behavior. Sintering was performed in the temperature range from 1000$^{\circ}C$ to 1300$^{\circ}C$. The substitution site of Cd$\^$2+/ is identified by XPS spectra. Although Cd$\^$2+/ is substituted into both A-site and B-site in PNN-PZ-PT, Cd$\^$2+/ prefers A-site to B-site. The density is influenced by substitution site of Cd$\^$2+/. If Cd$\^$2+/ replaces Pv$\^$2+/, weight gain is observed during sinterig process. On the contrary, if Cd$\^$2+/ replaces Ni$\^$2+/, weight loss is promoted during sintering. From these weight changes, it is believed that Cd$\^$2+/ changes the bonding strength between B-site cation and oxygen of octahedron in perovskite structure. The changes of lattice parameters as a function of Cd$\^$2+/ content were consistent with those of the bonding strength. The densities of A-site-doped compositions were higher than those of B-site-doped composition.

• 한국토양환경학회지
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• 제4권1호
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• pp.119-126
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• 1999

This study was carried out to estimate the effect of forest fire on physical and chemical properties of soil The forest fire was in April 1995 at Kongju of Chungnam. Soil samples were collected at 0~5cm, 5~10cm, and 10~20cm soil depths in September 1998 from the burned and unburned sites. Soil organic matter concentrations at 0~5cm and 5~10cm soil depths were significantly greater in unburned site than in burned site. Soil concentrations were greater in unburned site than in burned site at all soil depths. Cation exchange capacity was significantly higher in unburned site than in burned site at 0~5cm soil depth. There were no differences in available soil P, exchangeable soil K, Ca, and Mg, and pH of soil between burned and unburned sites. Soil water content at 0~5cm soil depth was significantly greater in unburned site than in burned site. Bulk density at 0~5cm soil depth was significantly higher in burned site than in unburned site. Forest fire had an adverse effect on physical and chemical properties of soil in this study, Burning of vegetation and forest 리oor organic matter in burned site may reduce organic matter supply to soil and increase soil erosion. Consequently, forest fire may have adverse influence on long-term site productivity.

• The Korean Journal of Ecology
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• 제21권3호
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• pp.187-193
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• 1998

Seasonal changes of nitrogen fixation and growth characteristics of Melilotus suaveolens population under different light conditions were quantitatively analyzed during growting period. Height growth of M. suaveolens population was promoted after April and the shade (site 2) showed 10-20% increase of height growth in compared with that of sunny (site 1). Seasonal changes of biomass were in creased after March, the biomass at site 1 attained 78.5% that of site 2 in May. Chlorophyll content was maintained high value from March to April but, Chlorophyll content of leaf at site 1 was decreased 11.7% compared to that of site 2 in May. The nitrogen content of each organ of M. suaveolens showed higher value in March and then decreased, the high nitrogen contents of reproductive organ were achieved at the flowering stage at site 1. The root nodule of M. suaveolens population appeared in March and showed maximum value in early June and decreased remarkably after July, the amount of nodule formation of M. suaveolens at site 2 showed higher than that of site 1. The nitrogen fixation activity of root nodule of M. suaveolens initiated with shoot growth and showed maximum value in mid April, and attained second peak in early June and then decreased after July. The total nitrogen fixation of the plant showed higher value at site 2 than that of site 1. From the overall results, M. suaveolens showed increased growth under half-shady, well ventilated barren soil than fertile sunny site.

• 가족자원경영과 정책
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• 제7권1호
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• pp.77-89
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• 2003

This study examines factors to influence consumers’reliability, and satisfactions for consumer anti-site, and willingness to visit that site again among consumers utilizing anti-sites. According to the results of this study, first, male, consumers utilizing electronic commerce were more likely to visit anti-site. Consumers were more likely to write their own message and reply other consumers’message in anti-site when they have purpose to complain about their dissatisfaction regarding the process of purchase behavior. Second, consumer's satisfaction is higher in cases of consumers having higher recognition of necessity of anti-site, visiting not required to affiliate the members of anti-site, and being reliable sites. Third, consumers were more likely to use anti-site again when they had higher recognition in the necessity of anti-site and were more satisfied. Finally, in order to facilitate the utilization of anti-sites, those solutions include systematic classification and management of writings listed in the site, active management of the site managers, solutions for criticisms on the writings listed and lack of objectivity of information provided, and active searches for solutions rather than listing of writings on discontents and resistance.

• 한국농촌건축학회논문집
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• 제12권2호
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• pp.117-124
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• 2010

This study has the purpose to examine the elements of deducing site plan of contemporary architecture in Jeju by looking into the mainly used measures and value in establishing the site plan of contemporary architecture of Jeju. Being the initial decision making stage that serves as basis in creating design alternative and completes overall designing alternative frame, Site plan is the core stage of initial architectural planning. In addition, analysis of site plan concept the central overall idea for site plan offers the perspective to access the problem for solution in site plan. Therefore, through the analysis of elements to deduce the site plan concept of the contemporary architecture in Jeju, the characteristics of site plan concept that considered the placement and locality of Jeju can be objectively examined in planning out the site plan of contemporary architecture in Jeju, and such analysis results may become objective basic data in planning out the site plan of the contemporary architecture in Jeju.

• Ecology and Resilient Infrastructure
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• 제9권1호
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• pp.77-82
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• 2022

본 연구에서는 서울의 세 지점에서 이동 및 고정오염원이 대기질과 도시 공원 토양의 특성에 미치는 영향을 파악하고자 하였다. 조사 대상지로는 도시에서 질소 침적의 주요 발생원인 이동 및 고정오염원의 여부에 따라 서울시 마포구의 하늘공원 (Site_M), 서울시 강남구의 일원에코파크 (Site_G), 서울시 서초구의 양재시민의 숲 (Site_Y)을 선정하였고, 각 사이트별 교통량과 대기질 농도, 토양 분석 결과를 비교하였다. 교통량은 Site_G와 Y에 이어 Site_M에서 가장 많았다; Site_M과 G는 Site_Y보다 자원회수시설과 더 가까웠다. 따라서, 본 연구에서는 PM과 NO₂ 농도가 Site_Y, G에서보다 Site_M에서 많을 것이며, 사이트마다 다른 대기 침적량에 의해 토양 질소 함량도 다를 것으로 예상했다. 예상과 동일하게 PM2.5와 NO₂ 농도는 Site_M과 G에서 높았지만 PM10 농도는 Site_Y에서 약간 높았다. 식물이 주로 흡수하는 무기질소의 형태인 NO₃^-의 함량은 세 사이트에서 유의한 차이가 보이지 않았고, NH₄⁺의 함량은 Site_Y에서 다른 두 지역에 비해 더 높았는데, 이는 대기 침적에 의한 결과라기 보다는 공원 관리 차원에서의 질소 비료 투입에 따른 영향인 것으로 생각된다. Site_Y에서 다른 사이트보다 낮은 pH를 보인 것 또한 과다한 비료 시용으로 인해 산성화가 일어난 것으로 생각된다. 그러나 토양 내 NH₄⁺ 함량이 상대적으로 적은 Site_M과 G를 포함한 모든 조사 대상지에서 식생이 건강하게 보이는 것으로 보아, 공원 관리에 있어서 과도한 비료 투입을 재고할 필요가 있음을 시사한다. 비록 이동 및 고정오염원으로 인해 대기의 PM, NO₂ 등의 농도가 달랐지만 그 영향이 토양의 질소 영양 상태에 직접적 영향을 미치지 않는 수준이었다.

• 한국지진공학회논문집
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• 제20권4호
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• pp.235-243
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• 2016

Korea is part of a region of low to moderate seismicity located inside the Eurasian plate with bedrock located at depths less than 30 m. However, the spectral acceleration obtained from site response analyses based on the geologic conditions of inland areas of the Korean peninsula are significantly different from the current Korean seismic code. Therefore, suitable site classification scheme and design response spectra based on local site conditions in the Korean peninsula are required to produce reliable estimates of earthquake ground motion. In this study, site-specific response analyses were performed at more than 300 sites with at least 100 sites at each site categories of $S_C$, $S_D$, and $S_E$ as defined in the current seismic code in Korea. The process of creating a huge database of input parameters - such as shear wave velocity profiles, normalized shear modulus reduction curves, damping curves, and input earthquake motions - for site response analyses were described. The response spectra and site coefficients obtained from site response analyses were compared with those proposed for the site categories in the current code. Problems with the current seismic design code were subsequently discussed, and the development and verifications of new site classification system and corresponding design response spectra are detailed in companion papers (II-development of new site categories and design response spectra and III-Verifications)

• Journal of Periodontal and Implant Science
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• 제32권2호
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• pp.291-302
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• 2002

In most of the previous studies, invasive and discrete techniques have been used to monitor the healing process of the gingival graft. However, Laser Doppler Flowmetry(LDF, floLAB(R), Moor Instruments Ltd., England) is a non-invasive technique for measurement of blood flow in the tissue and also allows continuous monitoring. Thus, we tested the usefulness of LDF in monitoring the healing process of free gingival graft at gingival recession. Eleven gingival graft site of 7 patients, including 5 males and 2 females, aged between 21 and 41 years (mean age 28.5) were monitored for the blood flow. The blood flow in gingival graft at coronal site, central site, apical site, mesial site and distal site was measured using LDF. Blood flow was measured at 1- week, 2- week, 3- week and 4- week after gingival graft surgery from 10 a.m. to 2 p.m. Time-course of the healing process was evaluated by statistical analysis using repeated ANOVA and Duncan test. The results were as follows : (1) Blood flow stayed increased for 2 weeks, and then, it was a tendency to decrease. (2) The blood flow at distal site had always higher than mesial site during the measuring periods. (3) The blood flow was high orderly after 1 week ; most coronal site, most apical site, central site. But that was high orderly after 2 week, 3 week, 4 week ; most coronal site, central site, most apical site. In conclusion, LDF was a useful and clinically adaptable method to monitor wound healing process. Our study suggested that it was important to protect surgical site to promote initial wound healing.

• 한국콘텐츠학회논문지
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• 제11권6호
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• pp.459-471
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• 2011

본 연구는 특급 호텔예식 웹사이트 품질이 웹사이트 만족과 신뢰 및 구매의도에 미치는 영향을 연구하고자 하였다. 이에 특급호텔 예식 웹사이트 이용경험이 있는 고객을 대상으로 설문지 총 300부를 배포하여 최종 244부를 실증분석에 이용하였다. 본 연구의 실증분석 결과를 통하여 다음과 같은 결론을 제시할 수 있다. 첫째, 호텔예식 웹사이트 품질인 정보품질과 서비스품질은 웹사이트 만족과 신뢰에 긍정적인 영향을 미친다. 둘째, 호텔예식 웹사이트 품질인 서비스품질은 구매의도에 유의수준에서 긍정적인 영향을 미치지만, 정보품질은 구매의도에 어떠한 영향도 미치지 않았다. 셋째, 호텔예식 웹사이트 만족은 웹사이트 신뢰와 구매의도에 긍정적인 영향을 미친다. 넷째, 웹사이트 신뢰는 고객의 구매의도에 긍정적인 영향을 미친다는 것이다. 따라서 특급호텔에서는 웹사이트 방문 고객을 위한 다양한 전략을 마련하여야 할 것이다.

• 한국건설관리학회논문집
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• 제23권5호
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• pp.34-42
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• 2022

건설현장배치는 프로젝트 공기와 비용에 큰 영향을 미치므로 이에 대한 최적화 및 자동화 연구가 수행되고 있다. 하지만, 이러한 연구의 목표변수인 건설현장배치의 수준을 평가하는 근거는 매우 제한적이다. 본 연구는 사용성평가 방법을 활용하여 건설현장배치의 수준을 평가하고 향후 건설현장배치 자동화 및 최적화 연구에서 초점을 맞추어야 하는 부분을 확인하고자 하였다. 설문결과 국내건설현장배치 사용성은 효과와 작업환경 항목에서 낮은 점수를 받았으며, 작업자가 관리자에 비해 낮게 평가하였다. 또한 작업환경 항목에서 낮은 점수를 받았으며 현장접근성과 시설 편의성이 낮음을 확인하였다. 이 연구는 건설현장배치 현황을 파악하고 개선방향을 제시함으로써 건설현장배치 자동화 및 최적화 연구의 진행을 위한 지식에 기여한다.