• Journal of Periodontal and Implant Science
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• 제25권1호
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• pp.167-178
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• 1995

It has been believed that the increased release of free oxygen radicals and their tissue damaging potency might be a contributing factor in the pathogenesis of periodontal disease. Antioxidant enzymes such as superoxide dismutase(SOD) and catalase can protect the tissue damage from the free oxygen radicals($O_2^-,H_2O_2$, and $OH^-$). In order to investigate the SOD- and catalase - activity in the blood plasma and red blood cells(RBCs) of the patients with perodontitis, 19 male periodontitis patients($25{\sim}35$ years old) who had good general health, more than 10 teeth with severely inflamed gingiva, attachment loss more than 6mm and bone loss were selected as periodontitis group, and 13 male volunteers($22{\sim}29$ years old) with good general and periodontal health were selected as normal group. After blood plasma and RBC were separated from peripheral blood of 2ml collected from antecubital vein of each subject, SOD- activity in blood plasma and RBCs was measured by the same method that Paoletti et al. did, and catalase - activity in RBC was measured by the same method that Beers et al, did. The difference of SOD- and catalase - activity between the normal and the periodontitis groups was statistically analyzed by Student t-test with SPSS/PC program.The results were as follows : 1. SOD activity in blood plasma was significantly lower in the periodontitis group($1.986{\pm}0.893$) than in the normal group($3.324{\pm}1.044$)(p<0.05). 2. There was no statistical significance in the difference of SOD- activity in RBCs between the periodontitis group($7.753{\pm}3.206$) and the normal group($8.116{\pm}1.192$)(p$242.8{\pm}45.6$) than in the normal group($280.2{\pm}32.6$)(p

• 한국ITS학회 논문지
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• 제6권2호
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• pp.15-25
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• 2007

본 연구는 RFID를 활용하여 교통정보를 수집 및 제공하기 위해 RFID 방식에 적합한 링크통행시간 추정 기법 개발 및 교통정보 수집체계로서의 적용가능성 평가를 목적으로 하였다. 이를 위해 기존 교통정보 수집 방식을 검토하여 RFID 수집 체계와의 차이점 및 특성을 파악한 후 교통정보생성구간 설정 및 통행시간 추정 기법을 개발하였으며, 현재 교통정보 수집을 위해 많이 이용되고 있는 GPS 방식과 비교분석하여 적용가능성을 평가하였다. 교통정보생성구간은 마스터 리더기를 기반으로 구축하였으나 실제 링크가 너무 길 경우 교통정보생성구간과 차이가 발생하여 이를 해결하기 위해 판단 로직을 추가하였다. 제주 시범사업지역의 조사 자료를 기반으로 통행시간 추정 기법에 대한 정확도 분석 결과 평균 88% 정도의 정확도를 보이는 것으로 나타났으며, GPS 방식(93%)과 비교할 때 거의 차이가 없는 것으로 나타났다. 또한 t검정으로 분석한 결과 p-value가 0.68로 통행시간의 차이가 통계적으로 없다고 나타났다. 이러한 결과로 볼 때 RFID 방식을 새로운 교통정보 수집체계로 적용가능한 것으로 사료된다.

• 구강회복응용과학지
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• 제33권2호
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• pp.119-126
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• 2017

목적: 이 논문의 목적은 발광 다이오드(Light Emitting Diode(LED))의 유무에 따른 전동칫솔의 항치태 및 항치은염 효과를 치은염 및 경도의 치주염 환자에서 관찰하는 것이었다. 연구 재료 및 방법: 30명의 환자를 실험군, 대조군으로 각각 15명씩 나누어 실험을 진행하였다. 실험군은 정상 작동의 LED 전동칫솔을 사용하였고 대조군은 LED가 나오지 않도록 개조된 동일 제품의 전동칫솔을 사용하였다. 기준(Baseline), 2주, 4주 후의 임상지표($L{\ddot{o}}e-Silness$ gingival index (GI), Quigley-Hein plaque index (PI))를 측정하여 Wilcoxon signed rank test, Mann-Whitney test를 통해 통계적 분석을 시행하였다. 결과: 실험군과 대조군 간의 시간에 따른 GI의 변화는 두 군 모두 시간에 따른 감소를 나타내었으나, 2주, 4주차에서 유의한 차이를 나타내었다. PI는 4주차에서 실험군에서 대조군보다 낮은 수치를 나타내었는데, 통계적으로 유의한 차이는 아니었다. 결론: 본 연구에서 LED가 장착된 전동 칫솔은 단기간의 연구에서 치은염의 감소효과를 보였고, 장기간의 관찰 시 치태의 축적을 감소시킬 수 있다 추측할 수 있었다.

• Journal of Chest Surgery
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• 제21권3호
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• pp.425-446
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• 1988

After 24 hours of preservation under 15 mmHg perfusion pressure the recovery rates of isolated canine hearts were determined. Preservation was performed in a cold room maintained at 4*C with 4 different types of perfusates bubbled with a mixture of 95% 0y and 5% CO~ using a modified perfusion unit designed in our institute. The perfusates used were as follows; Group 1: Krebs-Henseleit solution, Group 2: Krebs solution added by albumin and PGE1. Group 3: Modified Wicomb*s solution, Group 4: Modified Collin*s solution. The extent of myocardial recovery was evaluated using a modified isolated carmine perfusion model by measuring heart rate, systolic arterial pressure, left atrial pressure[LAP] and cardiac output. In addition to the above hemodynamic parameters, biochemical and enzymatic assays from perfusates and electron microscopic changes of the myocardium were also studied. The results were as follows; 1] The heart recovery rates were 41.6%, 53.4% and 108.9% in groups 1, 2 and 3, respectively, and group 3 elicited the best result[p< 0.001]. The heart beat was never recovered in group 4. 2] Recovered systolic arterial pressures[mmHg] were 63.3% in group 1, 94.9% in group 2 and 94.3% in group 3. 3] LAPs[mmHg] were 20 in group 1, 13.5 in group 2 and 11.2 in group 3, which suggested that the best myocardial preservation was elicited in group 3[p< 0.05]. 4] Cardiac output, the sum of aortic stroke volume and coronary leakage, were 69.1% in group 2, and 90.7% in group 3, but these were not statistically significant[p=0.24]. No aortic stroke output was measured in group 1 and 4. 5] The degree of myocardial edema increase was 17.5` in group 1, 24.6% in group 2, 20.9% in group 3 and 55.3% in group 4. But there were no statistical differences in each group[p= 0.08]. 6] CPK-MB[U/L] levels were increased 750% and 332%[p< 0.05], glucose levels[mg/dl] 60.5% and 78.2% and SGOT[U/L] levels 523% and 333%, in groups 2 and 3, respectively. Biochemical and enzymatic assays could not be performed in group 1 and group 4, because of poor recovery of heart beat. 7] Electron microscopic findings in the myocardium of most groups revealed slight to moderate muscle cell and mitochondrial edema. But all these findings were within the limits of reversible change. From these above results, it is suggested that modified Wicomb*s solution seems to be the most useful physiologic salt solution for preservation of the heart. We propose that after further study and improvement, our portable continuous hypothermic perfusion system will contribute to the development of a better preservation method for donor hearts for human heart transplantation.

• 유통과학연구
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• 제13권11호
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• pp.101-109
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• 2015

Purpose - A traditional retail market is a place that offers economic opportunity to employees and employers alike it also is a place where the community can meet. The Korean government has invested three trillion won to improve physical and non-physical aspects in traditional retail markets since 2004. However, little research on this has been conducted. We explore this research gap that could lead to theory extension. We analyze consumption behavior with respect to traditional retail markets through an empirical analysis, thus overcoming limits in previous research. We empirically analyze policy effects of traditional retail market projects supported by the Korean government. Research design, data, and methodology - We propose a traditional retail market improvement plan via the relation between cause and effect resulting from the analysis. More specifically, logit analysis was carried out with 1,754 consumers in 16 cities nationwide. In order to analyze consumer consumption behaviors nationwide, the probability was analyzed using a logit model. This research analyzes the link between support and non-support by the Korean government using binary values. The dependent variable is whether Korean government support is implemented; the binomial logistic regression is used as the statistical estimation technique. The object variables are:1 (support) or 0 (nonsupport), and the prediction value is between 1 and 0. As a result of the factor analysis of questions related to attributes of service quality, four factors were extracted: convenience, product, facilities, and service. Results - The results indicate that convenience, product, and facilities have a significant influence on consumer satisfaction in accordance with the government's traditional retail market support. Additionally, the results reveal that convenience, product, facilities, and service all have a significant influence on consumer satisfaction in a traditional retail market's service quality and consumer satisfaction. Finally, the analysis indicates that the highly satisfied traditional retail market customer has a significant influence on revisit intention. Moreover, the results reveal that the highly satisfied traditional retail market customer has a significant influence on recommendation intention. Conclusions - This research focused on consumers nationwide to measure policy effects of traditional retail markets compared to previous research that focused on one traditional retail market or a specific area. We verified the relationship of service quality and customer satisfaction and consumer behavior based on service quality theory. The results indicate that consumer satisfaction of traditional retail markets supported by service quality factors has a significant impact. In a concrete form, the results indicate that these effects are from facility modernization projects and marketing support projects of the Korean government. The results also imply that these facility and management support effects from the Korean government have been consistent. We realize that the Korean government has to selectively support traditional retail markets in major cities and small and medium-sized cities. To that end, the Korean government needs to select a concentration strategy for the revitalization of traditional retail markets.

• Asian Pacific Journal of Cancer Prevention
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• 제14권3호
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• pp.2059-2065
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• 2013

This goal of this research was to evaluate the cost-effectiveness of the National Cancer Screening Program (NCSP) for breast cancer in the Republic of Korea from a government expenditure perspective. In 2002-2003 (baseline), a total of 8,724,860 women aged 40 years or over were invited to attend breast cancer screening by the NCSP. Those who attended were identified using the NCSP database, and women were divided into two groups, women who attended screening at baseline (screened group) and those who did not (non-screened group). Breast cancer diagnosis in both groups at baseline, and during 5-year follow-up was identified using the Korean Central Cancer Registry. The effectiveness of the NCSP for breast cancer was estimated by comparing 5-year survival and life years saved (LYS) between the screened and the unscreened groups, measured using mortality data from the Korean National Health Insurance Corporation and the National Health Statistical Office. Direct screening costs, indirect screening costs, and productivity costs were considered in different combinations in the model. When all three of these costs were considered together, the incremental cost to save one life year of a breast cancer patient was 42,305,000 Korean Won (KW) (1 USD=1,088 KW) for the screened group compared to the non-screened group. In sensitivity analyses, reducing the false-positive rate of the screening program by half was the most cost-effective (incremental cost-effectiveness ratio, ICER=30,110,852 KW/LYS) strategy. When the upper age limit for screening was set at 70 years, it became more cost-effective (ICER=39,641,823 KW/LYS) than when no upper age limit was set. The NCSP for breast cancer in Korea seems to be accepted as cost-effective as ICER estimates were around the Gross Domestic Product. However, cost-effectiveness could be further improved by increasing the sensitivity of breast cancer screening and by setting appropriate age limits.

• 한국보육지원학회지
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• 제11권6호
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• pp.133-151
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• 2015

본 연구는 유아의 자기조절 및 어머니의 양육행동과 스마트기기 중독경향성이 유아의 스마트기기 과다이용에 미치는 영향을 파악하고자 하였다. 연구대상은 유아교육기관에 다니는 3~5세 유아들과 그들의 어머니 166명이었으며, 통계 방법으로는 빈도분석, 상관분석, 위계적 회귀분석을 실시하였다. 결과는 다음과 같다. 첫째, 유아의 스마트기기 이용 실태는 주 1~2회, 10~30분 정도, 주말에 가장 많이 이용하였다. 대부분 유아들은 3세 이전에 스마트기기를 이용하기 시작하였고, 부모를 통해 접근하였으며, 형제 자매와 주로 함께 이용하였다. 이용 규칙이 있는 경우는 66.3%였고, 자녀의 재미와 흥미를 위해 가장 많이 이용하게 하였다. 둘째, 변인들 간의 상관관계에서 어머니의 스마트기기 중독경향성, 과보호 허용과 유아의 스마트기기 과다이용이 정적으로 관련이 있었으며, 온정 격려, 한계설정, 유아의 자기조절과는 부적인 상관이 있었다. 유아의 스마트기기 과다이용에 있어서 어머니의 스마트기기 중독경향성이 가장 영향력 있는 변인으로 밝혀졌다. 본 연구 결과는 유아들의 스마트기기 이용에 대한 가이드라인을 제공하기 위한 방안을 모색하고 유아를 위한 올바른 스마트기기 이용에 대한 방향을 설정하는 기초 자료로 활용되는데 그 의의를 찾을 수 있다.

• Journal of Periodontal and Implant Science
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• 제50권5호
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• pp.340-354
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• 2020

Purpose: This pilot study was conducted to evaluate the cleaning efficacy of an angled implant brush for home oral hygiene of full-arch fixed-implant prostheses. Methods: Forty-one patients treated with a full-arch implant rehabilitation in the maxilla or mandible (164 implants) for at least 4 months were enrolled. The screw-retained fixed prostheses were removed and baseline (T0) parameters were recorded, including plaque index (PI), probing depth (PD), and bleeding on probing (BOP). All patients completed a 5-item questionnaire on hygiene maintenance and received an implant brush for home hygiene. After 1 month (T1) PI, PD, and BOP were recorded again and patients completed a 7-item questionnaire to evaluate their satisfaction with the implant brush. One-way repeated-measures analysis of variance was conducted to evaluate the significance of changes in PI, PD, and BOP. A P value <0.05 was considered to indicate statistical significance. Results: A statistically significant reduction of BOP (0.62±0.6 at T0 vs. 0.5±0.5 at T1; P=0.032) was found, while no statistically significant changes in PD (1.74±0.5 mm at T0 vs. 1.77±0.5 mm at T1; P=0.050) or PI (1.9±0.7 at T0 vs. 1.7±0.7 at T1; P=0.280) occurred. According to the 7-item questionnaire, patients reported no difficulty in using the angled brush (63.4%) and deemed it highly (46.3%) or very highly (4.8%) effective in improving their home oral hygiene. Conclusions: Within the limits of the present pilot study, the patients experienced a reduction of BOP 1 month after being instructed to use the angled implant brush. The angled implant brush appeared to be a well-accepted device for home-care hygiene of full-arch fixed-implant rehabilitations.

• 한국산업보건학회지
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• 제7권2호
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• pp.196-208
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• 1997

This study was performed to estimate quartz contents in the both bulk and airborne dust samples and to determine particle size distribution of airborne dust from the selected foundry operations. Total dust samples were collected by a 37mm cassette and respirable by a 10 mm nylon cyclone. Particle size distributions were determined by a Marple's 8-stage cascade impactor at the melting, molding, shakeout and finishing operations. The presence of elements in the dust samples were confirmed by the scanning electron microscopy equipped with the energy dispersive x-ray spectrometry. The quartz contents were estimated using the intensity of the absorption peak of quartz at 799 cm-l by the Fourie Transformed Infrared Spectroscopy (FTIR). The results were as follows: 1. The analysis of data from cascade Impactor showed bimodal distributions of particle size at the melting, molding and shakeout operations. Mass median aerodynamic diameters for the distributions determined by histogram were $0.48-1.65{\mu}m$ for small and $13.43-19.58{\mu}m$ for large modes. In the dust samples collected at the finishing operations, however, only a large mode of $18.89{\mu}m$ was found. 2. The percentages of total to respirable dust concentration calculated from the impactor data ranged from 42 % to 66 %. The average concentrations of respirable dust by cyclone were $0.85-1.28mg/m^3$ collected from the workers, and were $0.23-0.56mg/m^3$ from the areas surveyed. Dust concentrations of personal samples were statistically significantly higher than those of area samples. The highest dust concentration was obtained from the personal samples of the finishing operation. 3. The mean percentages of silicon and oxygen estimated by SEM-EDXA in the bulk samples ranged from 35.83 % to 36.02 % and from 39.93 %-41.64 %, respectively. 4. The average quartz contents estimated by FTIR in the respirable dust from personal samples ranged from 4.32 % to 5.36 % and 4.54 % to 4.70 % in the bulk samples. No statistical difference of quartz content was found between foundry operations. In this study, quartz content was quantified by FTIR. Although no statistically significant difference in quartz content between airborne and bulk, samples and between different foundry operations was found, it is recommended that quartz content in the individual sample of respirable dust be analyzed and the results be used either to select an applicable quartz limits or to calculate the exposure limit. Further studies, however, are needed to compare the results by FTIR and XRD since it is reported that the quartz content determined by FTIR is different from that by XRD.

• 한국경제지리학회지
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• 제9권3호
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• pp.318-340
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• 2006

지난 10여년 동안 새로운 내생적인 경제성장의 동력으로서의 지식창출활동에 대한 관심이 크게 고조되면서, 지식기반경제에서 지식창출을 측정하는 지표로서 특허의 중요성이 더욱 부각되고 있다. 선진국의 경우 지식창출활동은 공간상에 특정지역으로 집중되거나 클러스터를 형성하는 것으로 분석되고 있다. 본 연구는 1981-2000년 동안 국내 특허 데이터를 토대로 하여 지식창출활동의 성장에 따른 공간분포패턴을 분석하는데 목적을 두었다. 등록된 특허 원시자료를 데이터베이스로 구축하여 공간통계와 지리정보체계를 활용하여 지식창출활동 패턴의 공간적 연관성을 분석하였다. 우리나라의 경우 지식창출량의 68.5%가 단지 상위 10개 도시에 집중되어 있을 정도로 매우 불균등하게 지식창출활동이 이루어지고 있으며, 지식창출활동의 공간분포 패턴은 유의미한 공간적 자기상관을 보이는 것으로 나타났다. 실제로 서울과 수원을 중심으로 하는 지식창출량이 많은 H-H형 클러스터는 수도권내에서만 형성되어, 지식창출활동의 확산은 공간의 제약성을 받고 있는 것으로 나타났다.