• Tunnel and Underground Space
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• v.16 no.1 s.60
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• pp.26-37
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• 2006

This study addresses the applicability of box fractal dimension, $D_B$, as an index of statistical homogeneity of fractured rock mass. The box-count method's capability in quantifying the combined effect of fracture density and size distribution is examined systematically. Total of 129 two-dimensional fracture configurations were generated based on different combinations of fracture size distribution and fracture density. $D_B$was calculated for the generated fracture network systems using the box-counting method. It was found that was standard deviation of trace length and fracture orientation have no effect on calculated $D_B$. The estimated $D_B$ was found to increase with increasing total density and/or mean trace length. To explore the field applicability of this study, the statistical homogeneity of fractured rock mass was investigated at the rock slope and the underground facility using the box-counting method as well as conventional contingency table analysis. The results obtained in this study clearly show that the methodologies given in this paper have the capability of determining the statistical homogeneity of fractured rock mass.

• Journal of the Korean Society of Radiology
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• v.13 no.7
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• pp.1005-1014
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• 2019

The purpose of this study is to evaluate the usefulness of coronary computed tomography angiography of coronary artery disease for the purpose fo health screening according to gender and age. In addition the association between hematological factors (Glucose, total cholesterol, visceral fat, body mass index, triglycerides, high density lipoprotein (HDL), low density lipoprotein (LDL)) and coronary artery disease is investigated. A retrospective analysis of coronary computed tomography angiography with 299 subjects showed that the detection rate of coronary artery disease was higher in men over 50 years of age and it was statistically significant. In particular, the prevalence rate of men (37.9%) was about 2 times higher than that of women (17.0%). Glucose and HDL as hematological factors associated with coronary artery disease were statistically significant. The prevention and management of coronary artery disease seems to require the control of glucose and high density lipoprotein (HDL). Although it is not statistically significant with other hematological factors, the need for management of coronary artery disease was identified. the coronary computed tomography angiography of coronary artery has higher radiation doses than other CT scans. Therefore, for the purpose of screening, coronary computed tomography angiography should be considered in consideration of the sex and age of the examinee, and detection of coronary artery disease through other non-invasive tests should be prioritized over coronary computed tomography angiography.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2003.07a
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• pp.76-76
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• 2003

This study was conducted to investigate dietary and other factors affecting bone mineral density (BMD) in Korean premenopausal women. Seventy-eight premenopausal women who visited health promotion center for health examinations volunteered to participate in this study and they were divided into two groups according to the bone status by T-score : normal or osteopenic group and osteoporotic group. The demographic and general characteristics, and dietary intake were surveyed using the questionnaire. BMDs of the lumbar spine and femoral neck of subjects were measured by dual energy X-ray absorptiometry. Serum samples were measured for Lipid concentration, and calcium, phosphorus, alkaline phosphatase as bone formation indicators. Urine was analysed for creatinine as bone resolution indicators. The results are as follows:The mean BMDs of the lumbar spine and femoral neck were 1.21 0.02g/cm$^2$ and 0.97 0.04g/cm$^2$, respectively and the BMD levels of osteoporotic group were significantly lower than that of normal or osteopenic group (p<0.001, respectively). Height in osteoporotic group was significantly lower than that of normal or osteopenic group (p<0.01), and bodyweight did not show any significant difference but had a lower tendency. Mean daily intake of energy was 1720 52ka1. When nutrient intake was compared with recommended dietary allowances (RDA) of subjects, calcium, Fe, vitamin A and riboflavin intakes showed means lower than RDA. The nutrient intake did not show any significant difference between normal or osteopenic group and osteoporotic group except intakes of protein fat and niacin. Serum and urine levels did not show any significant differences between normal or osteopenic group and osteoporotic group and all were within normal range, however, serum alkaline phosphatase level of osteoporotic group was significantly higher than that of normal or osteopenic group (p<0.001). Height showed positive correlations with lumbar spine bone mineral density (LBMD, r=0.332, p<0.01), no correlation was found with femoral neck bone mineral density (NBMD). Age, age at menarche, bodyweight, body mass index (BMI) and obesity showed no correlation with BMD. The BMD of the lumbar spine was significantly and positively related to the intake of niacin and vitamin C (r=0.236, p<0.05; r=0.274, p<0.05). Serum levels of calcium and phosphorus showed a negative correlation with LBMD (r=-0.698, p=0.0001; r=-0.503, p=0.0001, respectively). The results suggested that the BMDs of the lumbar spine was positively related to the intake of niacin and vitamin C in premenopausal women. Therefore, this study confirmed that one of the most effective way to minimize bone loss would be higher intake of niacin and vitamin C rich foods and habitual physical activity may have a beneficial effect on BMD in premenopausal period.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6694-6701
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• 2014

The aim of this study was to identify the correlation between low density lipoprotein (LDL) cholesterol and the pulmonary function. This study enrolled premenopausal women in their aged 40s, who visited the health promotion center of a general hospital more than two times. A total of 384 subjects were classified into four groups based on their LDL-cholesterol levels; A, LDL(mg/dL)<100 at both initial and follow-up; B, LDL<100 at initial but ${\geq}100$ at follow-up; C, $LDL{\geq}100$ at initial but <100 on follow-up; and D, $LDL{\geq}100$ at both the initial and follow-up test. The result showed no significant differences in the pulmonary function between the four groups. Multiple linear regression analysis, which was adjusted for age, body mass index, smoking, exercise, and follow-up duration, showed a significant negative relationship between the changes in the LDL and the changes in the $FEV_1/FVC$ (${\beta}=-0.109$, S.E.=0.029, P<0.001), but not in the $FEV_1$ and FVC. In conclusion, there was a significant but weak relationship between the LDL and pulmonary function. Further larger studies will be needed.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.4
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• pp.549-563
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• 2008

The purpose of this research is to identify the urban structure in Korea. Though there is research regarding urbanization, there is little regarding the urban structure of the Korean economy. In this paper, two issues will be discussed: the measurements of inter-city and intra-city structure in Korean Metropolitan Statistical Areas (MSAs), which is newly defined. First, the city size rank rule, widely known as Zipf’s Law, will illustrate Korean the inter-city structure. The city size rank rule gives an idea whether Korean MSAs are balanced or not. In general, Korea has a heavy concentration in the Seoul MSA in terms of population. It could be either that the Seoul MSA is too big or that the Busan MSA is too small or both. If this is the primacy problem, a decentralization policy is necessary. On the other hand, if it is a second city problem, development policies for the Busan MSA and Daegu MSA are more important. Next, the Korean intra-city structure will be discussed. The evolutions of the MSAs explain intra-city structure by analyzing population density function and the housing price function. Some large MSAs such as Seoul and Busan have experienced urban sprawl, while other MSAs have experienced urban concentration. The population density gradient by the distance from the ARC GIS shows the growth rate of a city. According to the Spatial Mismatch Index between population and employment, the Ulsan MSA, Gwangju MSA, and Suwon-Hwaseong-Osan MSA are more mismatched, while the Daejeon MSA and Incheon MSA are less mismatched. Therefore, these analyses of Korean urban structure are meaningful in developing regional policy.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.2
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• pp.76-86
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• 2012

Macrozoobenthos were collected from 24 sites using small grab ($0.05m^2$) in order to see the spatial distribution of them at Sueocheon stream at the northern part of Gwangyang Bay during summer season when the maximum ecological processes are occurring. A total of 44 species of macrozoobenthos occurred, and their mean density was $789individuals/m^2$. Mollusks was the dominant faunal group accounted for 43.1% and 86.8% of the whole community density and biomass, respectively. Top five dominant species were a molluscan, Corbicula japonica (40.7%), two polychaete worms, Neanthes japonica (19.3%) and Heteromastus filiformis( 8.1%), and two crustaceans, Paranthura japonica (6.9%) and Jaeropsis sp. (6.9%). Species diversity index was very low with mean value of 1.12 and maximum value was recorded at the river mouth. At the upper stream, a brackish water species such as Corbicula japonica showed their maximum population density. The overall distribution of stream macrobenthos showed a rather simple pattern along with salinity and grain size gradients with few brackish water species occurring at coarse sediments in the stream but more diverse faunas inhabiting fine sediments in the river mouth.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.7-16
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• 2004

The purpose of this study was to find the characteristics of travel behavior and accessibility in terms of spatial structure. We analyzed travel behaviors and accessibility using a mode choice model and the Complementary Accessibility Index(CAI). The urban spatial structures that were compared were a compact city (CC) versus a sprawled city (SC), and high residential density districts (HD) versus low residential density districts (LD). First, CC and HDs residents had a shorter commuting distance than the CC and LDs residents. Second, behavior models showed that the use of Private cars for commuting in SCs was found to be greater than private car use in CCs, and that public transportation modes would be encouraged in CCs. Third, changes associated with the time and cost of commuting by private car generally affect the demand for public transportation modes in the CC. Also, analysis of cross elasticity suggests that changes of subway travel time affect the demand for buses very elastically. Fourth, the CAI of SC and LD were superior to the CC and HD even though the SC inefficient urban forms in terms of spatial structure. So, the spatial distribution of population density was also found to be an important factor affecting accessibility and energy savings.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3337-3343
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• 2013

This systematic review was conducted to assess the efficacy and safety of bisphosphonates for prevention and treatment of osteopenia or osteoporosis in men with non-metastatic prostate cancer receiving androgendeprivation therapy. We searched for randomised controlled trials (RCTs) of bisphosphonates compared with placebo from Pubmed, Embase, the Cochrane Library, and ISI - Science Citation Index. Meta-analyses of prespecified outcomes (bone mineral density, fractures, and adverse events) were performed using Review Manager. Ten RCTs with a total patient population of 1,017 were identified. There was generally more improvement in bone mineral density of the lumbar spine for patients who received bisphosphonate treatment than placebo or other medical treatment at 12 months (WMD 6.02,95%CI 5.39 to 6.65). Similar effects were also observed for total hip, trochanter or femoral neck bone mineral density. However, there was no significant reduction in fractures. Fever and gastrointestinal symptoms were the most common adverse events (10.4% vs. 1.2%; 0.10% vs. 0.03%). Currently, our meta-analysis suggested that oral and intravenous bisphosphonates caused a rapid increase in spine and hip or femoral BMD in non-metastatic prostate cancer patients receiving androgen-deprivation therapy. Fever and gastrointestinal symptoms were common with the use of bisphosphonates. These short-term trials (maximum of 12 months) did not show fracture reduction. In future, more efficient performance of higher quality, more rigorous, large sample, long-term randomised controlled trials (>12 months) are needed where outcomes are detailed.

• BMB Reports
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• v.37 no.6
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• pp.691-699
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• 2004

Osteoporosis is a disease characterized by exaggerated loss of bone mass, with as much as 50 to 85% of the variation in bone mineral density (BMD) commonly accepted as being genetically determined. Although intensive studies have attempted to elucidate the genetic effects of polymorphisms on BMD and/or osteoporosis in several genes, the genes involved are still largely unknown. The possible associations of genetic variants in five-candidate genes (IL10, CCR3, MCP1, MCP2 and GC) with spinal BMD were investigated in Korean postmenopausal women (n = 370). Fourteen SNPs in five candidate genes were genotyped, and the haplotypes of each gene constructed. The associations of adjusted spinal BMD by age, year since menopause (YSM) and body mass index (BMI), with genetic polymorphisms, were analyzed using multiple regression models. Genetic association analysis of Korean postmenopausal women revealed that IL10 -592A > C and/or IL10 ht2 were associated with decreased bone mass, whereas no significant associations were observed with all polymorphisms in other genes. The levels of spinal BMD in individuals bearing the IL10 -592CC genotype were lower ($0.78{\pm}0.16$) than those in others ($0.85{\pm}0.17$) (P = 0.02), and the BMD of IL10 ht2 bearing individuals were also lower ($0.82{\pm}0.15$) than those in others ($0.85{\pm}0.17$) (P = 0.04). Our results suggest that variants of IL10 might play a role in the decreased BMD, although additional study might need to be followed-up in a more powerful cohort.

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.187-198
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• 2011

The objective of this study is to analyze the flora and forest vegetation of trails with high visitor density at Molundae. Nine quadrats of $20{\times}20m$ were selected for the survey. The survey was conducted from April to October 2010. The obtained results are summarized as follows. Plot1, plot2, plot3, plot4, plot6, and plot7 were located at slopes of $5{\sim}20^{\circ}$, 17~40m above sea level, and were formed with the colony of Japanese black pine(Pinus thunbergii Parl) and Japanese black pine(Pinus thunbergii Parl)-white oak(Quercus aliena Blume). Tree layer had the height of 8~20m, and the coverage of 50~70%, while subtree layer had the height of 3-8m, and the coverage 30~80%. On the other hand, shrub layer had the height of 2~4m, and the coverage of 10~30%, and herb had the height of 0.2~1m and coverage 5~20%. Plot5, plot8, and plot9 were located at the summit areas of 57~78m above sea level, and $0^{\circ}$ slope. Japanese black pine(Pinus thunbergii Parl) formed a community there. Tree layer was 8~20m high, and covered 60~70%, of the area, and subtree layer was 6~8m high, and coverage 30~40%. Shrub layer had the height of 2~6m, and the coverage of 30%, while herb layer had the height 0.2~2m, and the coverage 20-80%. Succession does not occur in the surveyed areas which have high visitor density. Artificially planted sawtooth oak(Quercus acutissima) trees were found to disturb succession and formation of multi-layer vegetation, resulting in the ecologically unstable forest. Therefore, the researcher suggested the strategy of managing the vegetation in the conclusion. This study has the limit in that the plots selected for the survey reflected only part of various trails in the Molundae area. It is necessary to suggest the vegetation management plans by selecting more diverse trail areas in consideration of the visitor density and behaviors, and analyzing the changes in vegetation quantitatively in order to manage the vegetation in urban areas damaged by visitors more effectively.