• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1995.11a
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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.

• Journal of Korea Soil Environment Society
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• v.4 no.1
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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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• v.21 no.3
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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.

• Journal of Family Resource Management and Policy Review
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• v.7 no.1
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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.

• Journal of the Korean Institute of Rural Architecture
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• v.12 no.2
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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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• v.9 no.1
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• pp.77-82
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• 2022

This study aims to understand how mobile and stationary air pollution sources affect the air quality and soil properties in urban parks. We selected three sites of urban parks in Seoul as follows: Ha-neul Park in Mapo-gu (Site_M), Ill-won Eco-Park in Gangnam-gu (Site_G), and Yangjae Citizen's Forest in Seocho-gu (Site_Y), and compared the results of each site's traffic volume, air quality concentration, and soil analysis. Traffic volume was high in Site_M, followed by Site_G and Y; Site_M and G were closer to the resource recovery facility than Site_Y. Hence, we hypothesized that PM and NO₂ concentrations in the atmosphere were higher in Site_M than Site_G and Y, causing different soil nitrogen content among sites due to different atmospheric deposition. Consistent with our hypothesis, the concentrations of PM2.5 and NO₂ were higher in Site_M and G than Site_Y, while Site_Y had higher PM10 than other sites. The soil NO₃^- contents showed no significant difference among three sites, whereas the soil NH₄+ content was extremely high in Site_Y. This high content of soil NH₄⁺ is thought to be due to acidification from excessive fertilization. Lower soil pH of Site_Y further supported the evidence of heavy fertilization in this site. Overall nitrogen dynamics implies that soil nitrogen status is more influenced by park management such as fertilization rather than atmospheric deposition. Despite of lower soil NH₄⁺ content of Site_M and G than Y, vegetation vitality looked similar among three sites. This indirectly indicates that excessive fertilizer input in urban park management needs to be reconsidered. This study showed that even if the air quality was different due to mobile and stationary sources, it did not directly affect the soil nitrogen nutrient status of the adjacent urban park.

• Journal of the Earthquake Engineering Society of Korea
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• v.20 no.4
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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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• v.32 no.2
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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.

• The Journal of the Korea Contents Association
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• v.11 no.6
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• pp.459-471
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• 2011

This study attempts to identify the effects of the perceived quality of the web-site of Deluxe Hotels Wedding on the satisfaction of web-site, trust of web-site, and purchasing intention of wedding products. For data analyses, a total of 300 questionnaire were distributed to those who had experience of web searching for Deluxe Hotels Wedding. Among them, 244 survey data were used for analyses. This study obtained following results. First, it found that information quality and service quality of web-site had the positive effects on the satisfaction and trust of web-site. Second, the service quality of web-site had the positive effect on purchasing intention of wedding products while information quality had no influences on it. Third, the satisfaction of web-site had the positive effect on trust of web-site and purchasing intention of wedding products. Fourth, trust of web-site had the positive effect on purchasing intention of wedding products. Therefore, Deluxe Hotels, Should be prepared the Various Strategy for the web-site Visit Guest.

• Korean Journal of Construction Engineering and Management
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• v.23 no.5
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• pp.34-42
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• 2022

Construction site layout is attracting attention as efficient use of construction site space greatly affects the duration and cost of the overall construction. Therefore, there are many studies that automate and optimize construction site layout planning. However, the usability of construction site, which consists of goal variables of the studies, has still been unknown. Therefore, the authors present the evaluation criteria for usability of construction site layout and evaluate the usability of domestic construction sites through user survey. Furthermore, the difference in usability between construction site managers and construction site workers was confirmed. As a result of the survey, domestic construction site layout had a low effectiveness and had the lowest score in the environment category. In addition, construction site workers scored lower overall than construction site managers. Through such usability evaluation results, it contributed to the construction site layout theory by assessing current construction site layout practice and suggesting an improvement direction for automating site layout planning.