• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.3 no.2 s.5
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• pp.129-140
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• 2004

In this paper, we conduct the research about optimal aggregation interval of travel time data on interrupted traffic flow and verify the reliability of AVI collected data by using car plate matching method in RTMS for systematic collection and analysis of link travel time data on interrupted traffic flow rural arterial. We perform Kolmosorov-Smirnov test on AVT collected sample data and on entire population data, and conclude that the sample data does not represent pure random sampling and hence includes sample collection error. We suggest that additional review is necessary to investigate the effectiveness of AVI collected sample data as link representative data. We also develop statistical model by applying two estimation techniques namely point estimation and interval estimation for calculating optimal aggregation interval. We have implemented our model and determine that point estimate is preferable over interval estimate for exactly selecting and deciding optimal aggregation interval. Our final conclusion is that 5-minute aggregation interval is optimal to estimate travel time in RTMS, as is currently being used our investigation is based on AVI data collected from Yang-ji to Yong-in $42^{nd}$ National road.

• Journal of Science and Technology Studies
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• v.17 no.1
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• pp.117-144
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• 2017

In Korea, currently, only the growth possibility of bioinformation industry has received the public attention, and social discussion on bioinformation management is meager. Based on this critical perspective, this study investigates the current status of public awareness of the bioinformation which can be a basis for the social discussion for bioinformation management. The most significant characteristics identified in the survey is that many citizens, while expressing their agreement on the use of biometric technology by purpose and taking an open stance on national fingerprint information collection, have considerable concern for the identity authentication system using the current biometric technology. In particular, the survey pointed out that it is hard to trust the institutions that collect the bioinformation. Also, the public expressed the particular concern for the health data including the body information and showed overwhelming consent for the necessity of more stringent regulation compared with other personal information. In regards to the medical information gathered from medical institutions, nearly 80% of the survey respondents did not agree on providing the information to commercial enterprises, and even 60% of them disagreed on using it for academic and statistical research. This result well demonstrates that thorough management of the bioinformation is required for its utilization.

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.5
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• pp.345-352
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• 2016

As aircrafts are being operated at high altitude, wing structures experience various fatigue loadings under cryogenic environments. As a result, fatigue damage such as a crack could be develop that could eventually lead to a catastrophic failure. For this reason, fatigue damage monitoring is an important process to ensure efficient maintenance and safety of structures. To implement damage detection in real-world flight environments, a special cooling chamber was built. Inside the chamber, the temperature was maintained at the cryogenic temperature, and harmonic fatigue loading was given to a wing structure. In this study, piezoelectric active-sensing based guided waves were used to detect the fatigue damage. In particular, a beamforming technique was applied to efficiently measure the scattering wave caused by the fatigue damage. The system was used for detection, growth monitoring, and localization of a fatigue crack. In addition, a sensor diagnostic process was also applied to ensure the proper operation of piezoelectric sensors. Several experiments were implemented and the results of the experiments demonstrated that this process could efficiently detect damage in such an extreme environment.

• The Korean Journal of Applied Statistics
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• v.28 no.4
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• pp.685-701
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• 2015

The low fertility rate and the unprecedented rapid pace of population aging is a significant factor degrading the national competitiveness and the social security system of Korea. The government has implemented various maternity incentives to alleviate the low birth problem; however, the policy seems in effective to solve the problem of low fertility. This study proposes a conditional birth-order specific fertility rate and investigates the policy effects of fertility transition in Korea to provide a basis for more effective policy development. The use of a conditional birth-order specific fertility rate allows for an effective calculation of the change and the effect in total fertility rate than a birth-order specific fertility rate. We compare the effects of the total fertility rate according to various scenarios that enables us to calculate how the total fertility rate can achieve the current multi-child childbirth support policy of the government and estimate how the total fertility rate can be achieved when focusing on the first or second childbirth support policy. We also summarize the research results on policy development for a practical increase in the childbirth that considers the rapid decrease in women of childbearing age (15-49 years) due to continued low fertility and present the number of childbirths in accordance with the total fertility rate.

• Biomolecules & Therapeutics
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• v.6 no.1
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• pp.37-44
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• 1998

This study was performed to examine the effects of DA-9601, a novel antiulcer agent extracted from Artemisiae Herba, on radiation colitis in the rat. Female Wistar rats received a 30 Gy dose of irradiation to the 2 cm of distal colon in length using an intrarectal applicator system. 30 mg/tg or 100 mg/kg of DA- 9601 was administered orally 30 min before and 4 h after radiation on day 1. And the same dose of DA-9601 was given to the animals twice a day from day 2 to 14. As a reference control, sucralfate suspension (100 or 300 mg/head) was given as an enema based on the same treatment schedule of DA-9601. Body weight change and the frequency of diarrhea were recorded during the observation period as markers of radiationinduced injury, All animals were sacrificed on day 15 for evaluation of macro- and microscopic findings and mucosal myeloperoxidase (MPO) activity. Radiated animals showed diarrhea, mucosal redness and histologic changes characterized by edema and eosinophilic infiltration of the periglandular lamina propria with loss of colonic epithelium. Radiation also significantly increased mucosal MfO activity of affected colon f\\\\\\\\`<0.05). However, most of these changes were completely protected by oral administration with DA-9601. DA-9601 reduced radiation-induced histologic alteration significantly in a dose-related manner (P<0.05). In addition, mucosal MPO activity in rats receiving high dose of DA-9601 decreased significantly when compared with that in radiated control. High dose of sucralfate (300 mg/head) alleviated radiation-induced histologic lesion, but failed to reach statistical significance. The results of this study suggest that DA-9601 can be useful for the prevention of acute clinical symptoms of radiation proctocolitis and that decrease of mucosal MPO by DA-9601 plays a role in its protective mechanism(s), at least in part.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.155-161
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• 2015

This study confirmed the correlation between the change of the cooling water in internal cooling system and the size of the ablation site of bovine liver in RF heat treatment equipment. The bovine liver was resection with $4{\times}4{\times}4cm^3$ in 2cm cool-tip and with $6{\times}6{\times}6cm^3$ in 3cm cool-tip for the experiments. Area and perimeter of the ablation site for bovine liver were measured by Freehand techniques of MRI. It showed area and perimeter decreased during cool-tip temperature rises 6 and 12 minutes ablation using a 2cm and 3cm cool-tip. The correlation of cool-tip temperature and area and perimeter was statistically significant the result are shown(p=.000). The measurements of area and perimeter were more accurate with MRI in actual measurements and MRI for ablation range. The statistical results using Paired sample T-test was also significant(p=.038). The ablation range of bovine liver decreased according as cooling water temperature increases in RF heat treatment equipment for reason of carbonization occurred due to does not accurately pass the RF energy. Therefore, it is considered the effect of RF heat treatment would be increased if the temperature of the cooling water consistently maintain the low temperature in order to reduce the generation of carbide at RF heat treatment and RF energy is delivered accurately.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.748-754
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• 2010

The contents of soil organic matter (SOM) and $Al_o+1/2Fe_o$ in soils are important criteria for the classification of new Andisols in Soil Taxonomy system. There are many soil types in Jeju Island with various soil forming environments. This paper was conducted to estimate the contents of soil organic matter and the content of ammonium oxalate extracted Al and Fe ($Al_o+1/2Fe_o$) using various environmental variables and to make soil property maps using a statistical analyses. The soil samples were collected from 321 locations and analyzed to measure the contents of SOM and $Al_o+1/2Fe_o$. It was analyzed the relationships among them and various environmental variables such as temperature, precipitation, net primary product, radiation, evapotranspiration, altitude, soil forming energy, topographic wetness index, elevation, difference surrounded area, and distances from the shore and the peak. We can exclude multi-collinearity among environmental variables with principal component analysis and reduce all the variables to 3 principal components. The contents of SOM and $Al_o+1/2Fe_o$ were estimated by multiple regression models and maps of them were made using the models.

• Journal of The Korean Association For Science Education
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• v.30 no.4
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• pp.472-486
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• 2010

The surveys for public awareness in relation to socio-scientific issues (SSI) have been limited to several topics such as public perception of risks about the issues and preference for some policies. To illuminate the public science culture literacy about SSI from a holistic perspective, this study aimed to develop an indicator system. For this purpose, the issue on climate change, which is currently one of the biggest issues worldwide, was adopted as a specific SSI and the framework centering on climate change was developed. Science culture literacy about SSI was defined as a lifestyle to identify SSI from various viewpoints and to cope with problems related to SSI appropriately. In the framework proposed, individual science culture indicators are divided into Potential and Activity area. The Potential consists of categories of Interest, Opinion and Understanding, whereas the Activity is composed of categories of Learning and Practice. To examine the reliability and validity of this framework statistically, the developed questionnaire was reviewed by science educators, environment experts and atmospheric scientists and was used to asked 777 secondary students. Based on the results of statistical analyses, the framework was modified and it consequently had 2 areas, 5 categories, 15 sub-categories, 34 indicators and 63 items. It is expected that the framework of science culture indicators for SSI could be used as a measurement tool for public awareness about various SSI topics.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.74-82
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• 2008

The purpose of this study is to reflect on the results of the assessment and analysis of landscape planning projects according to planning phases in a landscape planning system based on landscape law. An assessment of the importance and performance of landscape planning elements by planning phases was studied by statistically descriptive analysis, variation analysis, statistical t-test and importance-performance analysis. As a result of the evaluation, the performance of existing landscape planning projects is 3.813 and the importance of planning elements is 5.648. This means that in spite of the importance of landscape planning elements, the performance of existing landscape planning projects is not sufficient to cover the importance of landscape planning elements. In addition, 'site landscape survey' and 'landscape design guideline' sections are not sufficient when they are compared to 'landscape concept plan' and 'landscape basic plan' to complete the landscape planning projects required by landscape law. It means also that the landscape survey and landscape design guidelines should be complementarily practiced in order to increase the effectiveness of landscape planning projects. As the research is practiced by survey methods on landscape planning projects which are only new development sites, the results cannot represent all types of landscape planning projects. Nevertheless, the results can be applied to new landscape planning at new development sites or old cities to increase effectiveness.

• Journal of Nutrition and Health
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• v.45 no.4
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• pp.372-389
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• 2012

The objective of this study is to select a simple and easy measurable food behavior checklist for the development of Nutrition Quotient (NQ) for children, which reflects children's diet quality, as well as to evaluate the validity of the items in the food behavior checklist. The first 36 items in the checklist were established by an expert review, modifying the preliminary 50 items in the checklist, which had been selected by a literature review and the Korean National Health and Nutrition Examination Survey data. 341 children in 5th and 6th grades at an elementary school participated in a one-day dietary record survey, and later responded to 36 food behavior questions of the checklist. Pearson's correlation coefficients between the responses to the food behavior checklist items along with the mean nutrient intakes of the children were calculated. From the result, in which responses of food frequency and food behavior items showed certain association with the dietary record data, a second checklist with 22 items was selected. A survey was conducted by using the second checklist. 1,393 children in the 5th and 6th grades at 12 elementary schools in metropolitan cities, such as Seoul, Busan, Gwangju, Daegu, Daejeon, and Incheon, participated in the survey. Further, an exploratory factor analysis was performed. After the analysis, 19 items (10 items from food frequency and 9 items from food behavior) were finalized as the food behavior checklist items for the NQ. The final 19 food behavior checklist items were composed of 5 factors: 'Balance', 'Diversity', 'Moderation', 'Regularity', and 'Practice'. This study is a significant first trial to establish a comprehensive system for evaluating children's food habit and diet quality. This checklist might need continuous modification and revision reflecting the change of children's dietary life and the social environment.