• Investigative Magnetic Resonance Imaging
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• v.3 no.1
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• pp.47-52
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• 1999

Purpose : The purpose of this study was aimed to evaluate the BOLD(blood oxygen level dependent) contrast fMRI(functional MR imaging) in the occipital lobe and to compare with the metabolic changes based on H MRS (MR spectroscopy) and MRSI (MR spectroscopic imaging) before and after visual stimulation Materials and Methods : Healthy human volunteers (eight males and two females with 24-30 year age) participated in this study. All of the BOLD fMRI were acquired on a 1.5T MR with EPI during supervised visual stimulation in the occipital lobe. The red flicker with 8Hz was used for visual stimulation. After imaging acquisition, the MR images were transferred into unix workstation and processed with acquired from the same location based on the activation map. MRSI (magnetic resonance spectroscopic imaging) was also acquired to analyze the lactate changes before and after stimulation. Results : The activation maps were successfully produced by BOLD effect due to visual stimulation. NAA (N-acetyle aspartate)/Cr (creatine) ratio varied only from $1.79{\pm}0.28{\;}to{\;}1.88{\pm}0.20$ in activation area before and after stimulation. However, the signal intensity of lactate was elevated $9.48{\pm}4.38$ times higher than before activation. Lactate metabolite images were consistent with the activation maps. Conclusion : The BOLD contrast fMRI is enough sensitive to detect the activated area in human brain during the visual stimulation. Lactate metabolite map presents the evidence of lactate elevation on the same area of activation.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.6
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• pp.62-72
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• 2015

The objective of this research is to investigate the different aspects in which users positively identify with indoor green walls and the influences that it has on usage behaviors. Under the hypothesis that public space users prefer locations with green walls, the effect on their behavior was observed. After installing indoor green walls, behavioral observations and questionnaires were carried out to analyze green wall preferences. The observation experiment was carried out for a total of 8 days in order to see what influences the preferences for of indoor green walls had on usage behaviors and compare a control group with an experimental group that experienced a green wall. The usage time data were put into an SPSS statistics program and used to run an independent sample t-test. The questionnaire was carried out for two days from March 1st to 2nd 2014 after the observation was completed, and was done by 224 users of the two areas. The results from the experiment are as follows. First, comparisons between the total usage time of seats adjoined to partitions in both the green walled area and the partitioned area showed that there was no preference for indoor green walls. Second, the results appeared to show a higher percentage of women users in the green walled area, compared to the original partitioned area. Third, it showed that partitions and plants did not have any influence on seat choices. Fourth, the questionnaire showed preferences for indoor green walls. Out of the 94 people who sat in the partitioned area, 11.7% answered that they wanted to sit in the green walled area, they couldn't due to the lack of available seats. Furthermore, out of the 130 people who sat in the green walled area, 24.6% said they chose the seat because of their preference for the green wall. Although 64.3% of users of the two areas said that they would choose the green walled area if under the same circumstances, the behavior observation did not reflect this.

• The Journal of Korean Academy of Prosthodontics
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• v.59 no.3
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• pp.261-270
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• 2021

Purpose. The aim of this study was (1) to compare the reverse engineering technique with other existing measurement methods and (2) to analyze the effect of implant angulations and impression coping types on implant impression accuracy with reverse engineering technique. Materials and methods. Three different master models were fabricated and the distance between the two implant center points in parallel master model was measured with different three methods; digital caliper measurement (Group DC), optical measuring (Group OM), and reverse engineering technique (Group RE). The 90 experimental models were fabricated with three types of impression copings for the three different implant angulation and the angular and distance error rate were calculated. One-way ANOVA was used for comparison among the evaluation methods (P < .05). The error rates of experimental groups were analyzed by two-way ANOVA (P < .05). Results. While there was significant difference between Group DC and RE (P < .05), Group OM had no significant difference compared with other groups (P > .05). The standard deviations in reverse engineering were much lower than those of digital caliper and optical measurement. Hybrid groups had no significant difference from the pick-up groups in distance error rates (P > .05). Conclusion. The reverse engineering technique demonstrated its potential as an evaluation technique of 3D accuracy of impression techniques.

• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.117-131
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• 2021

Urban development is continuously being carried out to stabilize housing supply. The importance of ecosystem services assessments considering the various urban spatial structures is emerging as land use change in the wake of urban development has impact on the provision of ecosystem services. However, few studies are available as to the effects of land use transition in agricultural land due to urban development on ecosystem services. The purpose of this study is to examine the applicability of decision-making in the urban planning process by analyzing the impact of land use change on ecosystem services due to urban development. Therefore, the scenario was set on before and after the city development, targeting Namyangju Wangsuk Zone 1 and InVEST model was used to compare and analyze changes in value of ecosystem services. Analysis results of ecosystem services before the urban development, it turned out that habitat quality and water yield increased overtime but carbon storage and crop production decreased. Analysis results of ecosystem services after the urban development indicated that all items in ecosystem services by scenario decreased more than in 2018. Among the scenarios of urban development, compact city had the lowest value of water resource supply but had the highest value in terms of habitat quality, carbon storage amount, and crop production. The study results demonstrate that the compact city has positive effects on ecosystem services and is expected to be used as the basic data for supporting policy decision-making in the establishment of future urban development and management plans.

• Korean Journal of Health Psychology
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• v.14 no.2
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• pp.277-292
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• 2009

This study investigated the responses of the autonomic nervous system of individuals with Type D personality during an acute stressful situation. Twenty-three female students of Type D personality and 23 female students with non-Type D personality. Stroop Color-Word Task was used to induce a stressful situation, heart rate variability (HRV) was used to measure the responses of the autonomic nervous system during the baseline, acute stress, recovery periods. To analyze the data, the repeated measures analysis of variance was used to compare the autonomic nervous system of the Type D group to that of the non-Type D group. Regression analysis is used to determine if the Type D scale and stress vulnerability predicted the activities of the autonomic nervous system during the baseline period. The results of this study demonstrated that the Type D group's normalized low frequency (LF norm) and ratio of low frequency to high frequency (LF/HF ratio) were higher than those for the non-Type D group, while its normalized high frequency (HF norm) was lower than that for the non-Type D group in all three periods. There were no statistically significant differences among the three periods in terms of LF norm, HF norm, and LF/HF ratio in the Type D group. The study demonstrated that the total scores of the Type DS-14 and scores of social inhibition and negative affect were independent predictors of LF norm and HF norm during the baseline. The Type D group showed increased activation of the sympathetic nervous system and/or decreased activation of the parasympathetic nervous system. These results support the hypothesis that the Type D personality is vulnerable to the stress. Also, the highly activated sympathetic and/or lowly activated parasympathetic nervous systems, which were observed in the Type D group during the baseline, indicated that the Type D individual is susceptible to psychosomatic disorders.

• The Journal of Korean Academy of Prosthodontics
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• v.50 no.1
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• pp.29-35
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• 2012

Purpose: The purpose of this study was to analyze temperature change along the implant-bone interface induced by grinding the occlusal surface of implant gold prosthesis and to compare the temperature generated by grinding of prosthesis with different cooling methods. Materials and methods: The experimental gold prostheses were fabricated with dental gold alloy and castable abutment. The prostheses had 3 cylindrical protrusions on the occlusal surface with 1mm in height. Temperature was measured using 16 thermocouple wires attached to the implant fixture surface and the fixture was embedded in an acrylic resin block inside the $37^{\circ}C$ water bath. Cylinders were grinded for a period of 30 second with a low-speed handpiece with green stone point. One cylindrical protrusion was grinded without cooling, the second one was grinded with air blow, and the third one was grinded with water-spray. Results: The mean maximum temperature was measured more than $47^{\circ}C$ of the implant and the maximum temperature was measured at the cervical portion of the implant in the group without cooling. There was statistically significant difference between the group without cooling and the groups with cooling (P<.05). However, there was no significant difference at all portion of implant in the groups with cooling (P>.05). Conclusion: The results of this study support that the grinding of implant gold prosthesis without cooling may damage the peri-implant tissue. The continuous use of air blow and water-spray adjacent to prosthesis during the grinding of implant gold prosthesis may prove to be beneficial for cooling of the implant.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1143-1152
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• 2012

We established a top-down methodology to estimate carbon footprint as national mean value (reference) with the statistical data on agri-livestock incomes in 2007. We also established LCI (life cycle inventory) DB by a bottom-up methodology with the data obtained from interview with farmers from 4 large-scale farms at Gunsan, Jeollabuk-do province to estimate carbon footprint in 2011. This study was carried out to compare top-down methodology and bottom-up methodology in performing LCA (life cycle assessment) to analyze the difference in GHGs (greenhouse gases) emission and carbon footprint under conventional rice cultivation system. Results of LCI analysis showed that most of $CO_2$ was emitted during fertilizer production and rice cultivation, whereas $CH_4$ and $N_2O$ were mostly emitted during rice cultivation. The carbon footprints on conventional rice production system were 2.39E+00 kg $CO_2$-eq. $kg^{-1}$ by top-down methodology, whereas 1.04E+00 kg $CO_2$-eq. $kg^{-1}$ by bottom-up methodology. The amount of agro-materials input during the entire rice cultivation for the two methodologies was similar. The amount of agro-materials input for the bottom-up methodology was sometimes greater than that for top-down methodology. While carbon footprint by the bottom-up methodology was smaller than that by the top-down methodology due to higher yield per cropping season by the bottom-up methodology. Under the conventional rice production system, fertilizer production showed the highest contribution to the environmental impacts on most categories except GWP (global warming potential) category. Rice cultivation was the highest contribution to the environmental impacts on GWP category under the conventional rice production system. The main factors of carbon footprints under the conventional rice production system were $CH_4$ emission from rice paddy field, the amount of fertilizer input and rice yield. Results of this study will be used for establishing baseline data for estimating carbon footprint from 'low carbon certification pilot project' as well as for developing farming methods of reducing $CO_2$ emission from rice paddy fields.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.57-64
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• 2011

Purpose: The purpose of this study was to compare the cleansing performance of a distilled water, a diluted solution of sodium hypochlorite as a household bleaching cleanser and three alkaline peroxide cleansers in vivo plaque deposits by using scanning electron microscope. Materials and methods: Five individuals were selected from department of the prosthodontics in Pusan National University Hospital, and each of them was inserted with specimens for plaque accumulation in their temporary dentures for 48 hours. The specimens were removed and cleaned by each cleansing agents for 8 hours. Scanning electron micrographs were made from the specimens at a magnification of ${\times}2,000$. A panel of ten persons with a dental or paradental background, but not directly involved in the study, was selected to analyze the photomicrographs to determine which denture cleanser was more effective in removing plaque. Results: Diluted solution of sodium hypochlorite was the most effective at removing plaque following $Polident^{(R)}$, $Cleadent^{(R)}e$, $Bonyplus^{(R)}$ and distilled water in order. But there was no significant difference of cleansing efficacy between diluted solution of sodium hypochlorite and $Polident^{(R)}$, $Polident^{(R)}$ and $Cleadent^{(R)}e$, $Cleadent^{(R)}e$ and $Bonyplus^{(R)}$, respectively (P > .05). Alkaline peroxide cleansers by themselves cannot adequately remove accumulated plaque deposits, especially if the deposits are heavy. Corrosion could be seen on the surface of non-precious alloy specimens immersed in diluted solution of sodium hypochlorite. Conclusion: It is recommended to use of alkaline peroxide type cleansers with brushing whenever possible, since denture cleanliness is often poor due to the relative inefficiency of these cleansers.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.15 no.3
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• pp.127-137
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• 2015

Purpose: The main aim of this study was to compare and analyze expression profiles of microRNAs (miRNAs) to establish miRNA signature of Fabry nephropathy related epithelial mesenchymal transition (EMT). Methods: Expression profiles of miRNAs in kidney tissue samples and cell lines from normal and Fabry disease mouse model were examined by miRNA expression microarray analysis followed by quantitative real-time polymerase chain reaction analysis (qRT-PCR). Results: In the miRNA expression microarray analysis of Fabry mouse kidney tissues compared to wild type mouse, 5 and 3 miRNAs among 1,247 miRNAs examined were up- and down-regulated, respectively. Among them, miR-149-5p was down-regulated about 2-fold in Fabry kidney samples. The down-regulations of miR-149-5p were observed in kidney tissues of under 35 week-old-Fabry mice. However, this down-regulation was not observed in kidney tissues of 42 week-old Fabry mice. In SV40 MES 13 cells, mouse mesangial cells, treated with globotriaosylsphingosine (lyso-Gb3), miR-149-5p was also downregulated. The down-regulation of miR-149-5p induced up-regulation of its target genes related to EMT. Conclusion: The miRNA expression array and qRT-PCR results show that miR-149-5p expression was decreased in kidney tissues of Fabry mice compared to wild type mice under 35 weeks of age. Along with the observation of miR-149-5p expression in Fabry disease cell models, these results indicate that the down-regulated miR-149-5p were related to the biological response of mesangial cells to lyso-Gb3 and also have influence to the transcriptional up-regulation of its target genes. These results suggest miR-149-5p might play important roles in the Fabry nephropathy.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.200-210
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• 2015

The modeling for fast pyrolysis of biomass in fluidized bed reactor has been developed for accurate prediction of bio-oil and gas products and for yield improvement. The purpose of this study is to analyze and to compare the CFD(Computational Fluid Dynamics) simulation results with the experimental data from the CFD simulation results with the experimental data from the reference(Mellin et al., 2014) for gas products generated during fast pyrolysis of biomass in fluidized bed reactor. CFD(ANSYS FLUENT v.15.0) was used for the simulation. Complex pyrolysis reaction scheme of biomass subcomponents was applied for the simulation of pyrolysis reaction. This pyrolysis reaction scheme was included reaction of cellulose, hemicellulose, lignin in detail, gas products obtained from pyrolysis were mainly $CO_2$, CO, $CH_4$, $H_2$, $C_2H_4$. The deviation between the simulation results from this study and experimental data from the reference was calculated about 3.7%p, 4.6%p, 3.9%p for $CH_4$, $H_2$, $C_2H_4$ respectively, whereas 9.6%p and 6.7%p for $CO_2$ and CO which are relatively high. Through this study, it is possible to predict gas products accurately by using CFD simulation approach. Moreover, this modeling approach should be developed to predict fluidized bed reactor performance and other gas product yields.