• Proceedings of the Korea Contents Association Conference
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• 2016.05a
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• pp.241-242
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• 2016

Recent abnormal climate change induces localized heavy rainfall and extreme disasters such as debris flow near urban area. Thus many researches have been conducted to estimate and prevent, especially in focus of physical behavior of debris flow. Even though it is hardly to consider overall related parameters to estimate the extent and degree of directly or indirectly damages due to debris flow. Those analytic restraint would be caused by the diversity and complexity of regional topographic and hydrodynamic characteristics of debris flow inside. We have utilized the Bayesian method to compensate the uncertainty due to the complex characteristics of it after analyzing the numerical results from FLO-2D and field measurement data. Revised values by field measurements will enhance the numerical results and the missing parameters during numerical simulation will be supplemented with this methodology. As a final outcome in this study, the risk index of debris flow damage will be suggested to provide quantitative estimation in terms of hazard protection including the impact on buildings, especially in inner and outer of urban area.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.4
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• pp.52-64
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• 2019

The purpose of this study is to analyze the impact of macroeconomic variables on air passenger demand and provide useful information to airport managers and policymakers. Therefore, using the quarterly macroeconomic indicators from 2002 to 2017, the relationship with air passenger demand was demonstrated by multiple regression analysis. In the previous studies, they used GDP, Korea Treasury Bond, KOSPI index, USD/KRW Exchange Rate, and WTI Crude Oil Price variables. In this study, we used the Coincident Composite Index, Employment Rate, Consumer Sentiment Index, and Private Consumption Rate used as additional variables. It has confirmed that if the consumption of research results expands or the economic environment is right, it will affect the increase in international passengers. In other words, it confirmed that the overall economic situation acts as the main factor determining air passenger demand. It confirmed that the economic environment at the past has a significant impact on air passenger demand.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.427-430
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• 2005

The quality of various noises generated in the refrigerator is one of the important factors in deciding quality of the product. The main focus of sound control design has been shifted from reduction of sound level to improvement of sound duality for customer's preference. Up to date the purpose of noise control is the minimization of noise level. However despite of gradual decrease of noise level, occasionally the perceptional quality of noise has not been improved. In this paper, the relation between subjective and objective evaluation of sound quality has established and sound quality index is developed using ANN for evaluation of refrigerator's noise of both the starting noise and the stable running noise of compressor. To verify the usefulness of the index, the results in this paper have been compared with those surveyed by Consumer Union in USA.

• Korean Journal of Ecology and Environment
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• v.41 no.4
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• pp.499-511
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• 2008

The major focus of this study is to evaluate a newly developed stream naturalness index system 'Habitat-riparian Indexing System (HIS).' There have been many studies that have assessed stream naturalness in order to provide information required for restoration. The results of these studies were enough for the purpose of the studies; however, the methodologies were limited especially with respect to rapid measurement and the representation of ecological habitats. Therefore, we derived crucial variables from a popularly utilized method and merged them with other criteria obtained from overseas approaches, resulting in the development of the HIS method. The stability of HIS was evaluated by comparing the results with the Stream Naturalness Index (SNI) of Cho (1997). We monitored 100 stream sites in the Nakdong River system using the two different methods for two sampling periods (spring and autumn), and the results were compared using statistical analyses. The determination coefficients between the index values from two methods were c.a. 0.6 for both seasons, and statistics revealed that HIS had a relatively higher stability, providing index values for stream environments. The results of this work suggest a possibility of the utility of HIS for other stream habitats.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.2
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• pp.163-173
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• 2020

Purpose: This study aimed to investigate the clinical and metabolic determinants of circulating soluble leptin receptor (CSLR) and free leptin index (FLI) in pre-pubertal obese male children. Methods: We conducted a preliminary cross-sectional study at three tertiary hospitals and one public primary school. Eighty obese male children without growth and developmental abnormalities aged 5-9 years were recruited. In these children, obesity was solely caused by excessive food intake, and not by acute illness, medications, endocrine abnormalities, or any syndrome. Body mass index (BMI), body fat mass, carbohydrate intake, fat intake, high density lipoprotein cholesterol level, low density lipoprotein cholesterol level, triglyceride level, and Homeostatic Model Assessment for Insulin Resistance are the potential determinants for leptin regulation, which is represented by CSLR level and FLI. Results: Carbohydrate was the main source of energy. BMI and body fat mass had negative weak correlation with CSLR and positive weak correlation with FLI. Furthermore, carbohydrate intake was found to be independently associated with CSLR based on the results of the multiple linear regression analysis. Following an increase in carbohydrate intake, CSLR level decreased progressively without any negative peak. Conclusion: Leptin regulation in prepubertal obese male children is associated with body composition and dietary intake. Carbohydrate intake is useful for predicting CSLR. Lipid profiles and insulin resistance are not related to both CSLR and FLI. Treatment and prevention of leptin resistance in obese children should focus on reducing BMI, fat mass, and carbohydrate intake.

• Geomechanics and Engineering
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• v.16 no.2
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• pp.125-140
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• 2018

Tianjin, which is located on the west shore of the Bohai Sea, is part of China's Circum-Bohai-Sea Region, where very weak clay is deposited. From the 1970s to the early $21^{st}$ century, Tianjin marine clay deposits have been the subject of numerous geotechnical investigations. Because of these deposits' geological complexity, great depositional thickness, high water content, large void ratio, excessive settlement, and low shear strength, the geotechnical properties of Tianjin marine clay need to be summarized and evaluated based on various in situ and laboratory tests so that Tianjin can safely and economically sustain more infrastructure in the coming decades. In this study, the properties of Tianjin marine clay, especially its consolidation properties, are summarized, evaluated and discussed. The focus is on establishing correlations between the geotechnical property indexes and mechanical parameters of Tianjin marine clay. These correlations include the correlations between the water content and the void ratio, the depth and the undrained shear strength, the liquid limit and the compression index, the tip resistance and the constrained modulus, the plasticity index and the ratio of undrained shear strength and the preconsolidation pressure. In addition, the primary consolidation properties of Tianjin marine clay, such as the intrinsic compression line (ICL), sedimentation compression line (SCL), compression index, $C_c$, coefficient of consolidation, $C_v$, and hydraulic conductivity change index, $C_{kv}$, are evaluated and discussed. A secondary consolidation property, i.e., the secondary compression index, $C_a$, is also investigated, and the results show that the ratio of $C_a/C_c$ for Tianjin marine clay can be used to calculate $C_a$ in secondary consolidation settlement predictions.

• Journal of Korean Society for Quality Management
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• v.49 no.2
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• pp.145-159
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• 2021

Purpose: A statistical similarity evaluation to compare pharmacokinetics(PK) profile data between nonclinical and clinical experiments has become a significant issue on many drug development processes. This study proposes a new similarity index by considering important parameters, such as the area under the curve(AUC) and the time-series profile of various PK data. Methods: In this study, a new profile similarity index(PSI) by using the concept of a process capability index(Cp) is proposed in order to investigate the most similar animal PK profile compared to the target(i.e., Human PK profile). The proposed PSI can be calculated geometric and arithmetic means of all short term similarity indices at all time points on time-series both animal and human PK data. Designed simulation approaches are demonstrated for a verification purpose. Results: Two different simulation studies are conducted by considering three variances(i.e., small, medium, and large variances) as well as three different characteristic types(smaller the better, larger the better, nominal the best). By using the proposed PSI, the most similar animal PK profile compare to the target human PK profile can be obtained in the simulation studies. In addition, a case study represents differentiated results compare to existing simple statistical analysis methods(i.e., root mean squared error and quality loss). Conclusion: The proposed PSI can effectively estimate the level of similarity between animal, human PK profiles. By using these PSI results, we can reduce the number of animal experiments because we only focus on the significant animal representing a high PSI value.

• Journal of Korean society of Dental Hygiene
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• v.9 no.1
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• pp.125-139
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• 2009

Objective : This study was performed in order to provide basic data for halitosis prevention and establish a device to efficiently eliminate halitosis and to analyze the factors that affect the halitosis. Methods : Oral examination on the Gingival index, CPITN, Tongue Plaque index, and OHI-S as well as halitosis measurement among 293 rural residents. Results : Gingival index was high at mild on female and at moderate on male(p=0.025). Sorting the result by age, mild was 54.1% in the 40s, and moderate was 49.5%, 42.0% and 70.0% each in the 50s, 60s, and the 70s(p=0.005). The need for dental plaque management was 100%. The need for scaling was high with 78.3%, 93.0%, 89.9%, and 90.0% each for the 40s, 50s, 60s, and 70s. The need for complex periodontal treatment was also high with 32.4%, 47.5%, 48.7% and 60.0%, each for the 40s, 50s, 60s, and 70s(p=0.050). The highest bad condition for OHI-S was 69.5%, and good being 18.9%, and very bad being 11.6%. For moderate tongue plaque index was 74.4% as the highest. As the level of education increased, the slight tongue plague was increased, but in contrast, the moderate and higher tongue plague index was decreased(p=0.010). OG under 50ppm was 61.1% on male and OG over 50ppm was 50.9% on female(p=0.041). In OG over 50ppm, CPITN was 52.1% and 41.9% in scaling and complex periodontal treatment group(p=0.018). OHI-S, in bad and very bad condition with OG, over 50ppm, was 48.7% and 46.9%(p=0.019). The higher tongue plague index showed significant amount of increase at OG and EG above 50ppm(p=0.006). $NH_3$, as the tongue plaque index increased, the wider range of distribution was shown(p=0.000). As for the multiple regression analysis result, there have been selected females and tongue plaque index as factors affecting OG. There have been selected age and tongue plaque index as factors affecting EG and there have been selected females as factors affecting on $NH_3$. Conclusions : With the aforementioned results in mind, the status of halitosis among rural residents is considered to bare a close relation with oral environments. we have to focus on correct tooth brushing methods and tongue brushing, with using tongue cleaner to remove fur of tongue plaque. Also, in order to analyze exactly the factors of individual halitosis, we need continuous and systematic study.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.90-98
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• 2016

High-rise buildings construction project have various risk factors. Major risk factors are negative results such as time delay and increase of costs. Therefore, this study was analyzed risk factors in construction stages of high-rise buildings using by PROMETHEE technique. For this, this research were identified risk factors through experts Focus Group Interview(FGI). And, PROMETHEE was used to setup evaluation standard for analysis of high-rise building construction risks. Next, the standard of evaluation index calculation was composed by using the definition level in PDRI. Preference function and evaluation index were identified through questionnaires. Through these processes, this study has calculated the importance of high-rise building construction risks using by PROMETHEE technique. As a result, high degree risk factors were as following. These are 'Operation plan of material lifting', 'Outrigger & Belt Truss Construction', 'Foundation work plan of high-rise building' and 'Considering a Structure concept of high-rise building'.

• The Korean Journal of Food And Nutrition
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• v.28 no.2
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• pp.178-188
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• 2015

The purpose of this study was to investigate the association of interpersonal relationships with snack preference and the intake frequency of snacks with a primary focus on obesity index and snack preparations in upper grade (5~6th) elementary school students. A total of 719 students in Gyeongsangnam-do province were recruited and a questionnaire-based survey was conducted. Data were analyzed using the SPSS V18.0. The results were as follows : A total score of interpersonal relationships was 94.5 (full marks 125), and the scores of 7 factors consisting interpersonal relationships were over 3.50(full marks 5.00). Overweight group had the lowest score in interpersonal relationships (p<0.01) and purchase group by oneself had a low score than the other groups in snacks preparation (p<0.001). Most favorite snacks were ice cream. Additionally, the snack purchase group showed higher scores than the cook group by family in 8 types of snack and a total score of preference (p<0.05~p<0.001). Milk and dairy products had the highest score in frequency of snack intake. And purchase group by oneself or family was a higher than cook group by family (p<0.01). Interpersonal relationships showed a positive effect on preference and intake frequency of milk and dairy products but their explanation powers ($R^2$) were very low. The findings of this study provide fundamental information impact factor in snack preference and frequency of snack intake.