• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6D
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• pp.549-556
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• 2012

Longitudinal tunnels are defined as tunnels with length of over 1km. Because of Korea's topographical conditions and as safety measures for linear design, many tunnels are inevitably being constructed in Korea. The number of longitudinal tunnels constructed on expressways amounted to 104 as of the end of 2010 with a total length of 192km. Given the increasing demand for tunnels and the increasing length of tunnels, a safety evaluation of longitudinal tunnels needs to be conducted. As such, this study selected design elements, transportation environment and delineation system as elements to check and tried to determine factors influencing road crashes. For this, tunnels have been classified based on history of crashes; ones with crashes and ones without crashes and statistically meaningful explanatory variables were selected. By using these variables, a logit model was development in order to better grasp the factors that directly and strongly influence crashes. The result, related to crashes as well as the analysis were utility tunnel interior materials of driving lane and passing lane, which are related to driver's visibility, lateral width widening to consolidate space in a tunnel, and annual average daily traffic (AADT) per lane. These results may be used in the future as analysis indicators when drawing up plans to prevent crashes in longitudinal tunnels.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.35-42
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• 2006

This study was conducted to find effective components on taste of kanjang made with barley bran. The result of stepwise multiple regression analysis with transformation of variables was that the 70.1% and 80.8% of taste of barley kanjang could be explained at step 6 and step 15, respectively, calculated from absolute value. And, the 83.0% and 84.3% of taste of barley kanjang was explained at step 6 and step 15, respectively, calculated from relative value transformed with logarithm. The contributing proportion of the ${\alpha}-ketoglutaric$ acid was the highest followed by citric acid, lavulinic acid and glutamic acid computed from absolute value, and the ${\alpha}-ketoglutaric$ acid was the highest followed by fructose, glutamic acid and valine calculated from relative value trans-formed with logarithm.

• Journal of the Korea Convergence Society
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• v.11 no.11
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• pp.283-291
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• 2020

The purpose of this study is to analyze the relative efficiency of the research results of the convergence research project (CAP, Convergence Research Center) and general trust research project under the auspices of the NST, as the qualitative assessment of the government's R&D investment has recently been emphasized. To achieve this objective, DEA, which is widely used for the relative efficiency of research results, was used. The analysis targets were focused on the case of the KBSI, and the quantitative assessment of the number of papers and patent applications using net research and labor costs as input indicators for the DEA was compared and analyzed through IF of the paper and SMART3 of the patent. The analysis results showed that convergence research projects were highly efficient from a qualitative perspective in terms of CCR standards and BCC standards. This suggests that convergence research is being conducted at a higher level than general entrusted research. As a result of this study, we would like to present the criteria for qualitative assessment, which the government has recently emphasized, and expand this study to provide implications for planning policies and research tasks for rational R&D investment choices for human resources and research funds by assessing the efficiency of qualitative perspectives on all institutions in the future.

• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.4
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• pp.111-121
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• 2007

Diagnosis and Prediction of urban industrial structure is a key subject for establishment of sustainable urban development plan. By this time, studies of industry-related urban spatial structure have been concentrated on measurement of space distribution by industry type mainly using data about urban industries or total worker numbers. Now, status of workers become an important issue so this study analyzed qualitative change of urban industrial structure in the view of space using work status classification system. For that, data for work status in 1994 and 2004 were collected in towns and villages, and space analysis units were coincided based on change data between 1994 and 2004. Then, it analyzed spatial distribution pattern of employment through qualitative standard called work status using GIS. The analysis results by work status type of Busan industrial structure in GIS circumstance were as below. First, traditional labor intensive industries met a limit and service and wholesale/retail sale industries went to be poor livelihood. Therefore, Busan's employment rate should be decreased and worker numbers were statistically increased, however, irregular and non-wage workers were suddenly increased. So, it was determined that the quality of employment in Busan area came down. Second, a traditional downtown area has dwindled; on the other hand, employment has been increased in new town or new industrial complex and in the area developed services rather than the manufacturing industry. It is expected that the result of this study may be meaningful as data to prepare for longterm industrial development plan through qualitative evaluation called work status as well as to make behavior pattern of industrial structure which is basis of urban development.

• Journal of Korea Technology Innovation Society
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• v.19 no.2
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• pp.254-279
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• 2016

Recently, with the conversion towards knowledge-based economy era, the importance of the evaluation for patent valuation has been growing rapidly because technology transactions are increasing with the purpose of practically utilizing R&D outcomes such as technology commercialization and technology transfer. Nevertheless, there is a lack of research on determinants of patent valuation by analyzing technology transactions due to the difficulty of collecting data in practice. Hence, to suggest quantitative determinants for the patent valuation which could be applied to scoring methods, 15 patent valuation models domestically and overseas are analysed in order to assure the objectiveness for subjective results from qualitative methods such as expert surveys, comparison assessment, etc. Through this analysis, the important 6 common determinants are drawn and patent information is matched which can be used as proxy variables of individual determinant factors by advanced researches. In addition, to validate whether the model proposed has a statistically meaningful effect, total 517 technology transactions are collected from both public and private technology transaction offices and analysed by multiple regression analysis, which led to significant patent determinant factors in deciding its value. As a result, it is herein presented that patent connectivity(number of literature cited) and commercialization stage in market influence significantly on patent valuation. The meaning of this study is in that it suggests the significant quantitative determinants of patent valuation based on the technology transactions data in practice, and if research results by industry are systematically verified through seamless collection of transaction data and their monitoring, we would propose the customized patent valuation model by industry which is applicable for both strategic planning of patent registration and achievement assessment of research projects (with representative patents).

• Tunnel and Underground Space
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• v.15 no.6 s.59
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• pp.425-431
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• 2005

A series of geotechnical surveys and in-situ tests were carried out to evaluate the stability of underground mine cave in an abandoned coal mine. After the closure of the mine, the underground mine drifts have been utilized for a tourist route since 1999. The dimension of the main cave is 5m width, 3m height and 230m length. The surrounding rock mass of the cave is consist of black shale, coal and limestone. Also, the main cave is intersected by two fault zone. Detailed field investigations including Rock Mass Rating(RMR), Geological Strength Index(GSI) and Q classification were performed to evaluate the stability of the main cave and to examine the necessity of reinforcement. Based on the results of rock mass classification and numerical analysis, suitable support design was recommended for the main cave. RMR and Q values of the rock masses were classified in the range of fair to good. According to the support categories proposed by Grimstad & Barton(1993), these classes fall in the reinforcement category of the Type 3 to Type 1. A Type 3 reinforcement category signifies systematic bolting and no support is necessary for the Type 1 case. From the result of numerical analysis, it was inferred that additional support on the several unstable blocks is required to ensure stability of the cave.

• Fire Science and Engineering
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• v.31 no.2
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• pp.52-60
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• 2017

Numerical simulations were performed to evaluate the habitability of an operator for a cabinet fire in the main control room of a nuclear power plant presented in NUREG-1934. To this end, a Fire Dynamics Simulator (FDS), as a representative fire model, was used. As the criteria for determining the habitability of operator, toxic products, such as CO, were also considered, as well as radiative heat flux, upper layer temperature, smoke layer height, and optical density of smoke. As a result, the probabilities of exceeding the criteria for habitability were evaluated through the sensitivity analysis of the major input parameters and the uncertainty analysis of fire model for various fire scenarios, based on V&V (Verification and Validation). Sensitivity analyses of the maximum heat release rate, CO and soot yields, showed that the habitable time and the limit criterion, which determined the habitability, could be changed. The present methodology will be a realistic alternative to enhancing the reliability for a habitability evaluation in the main control room using uncertain information of cabinet fires.

• Journal of dental hygiene science
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• v.9 no.4
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• pp.419-426
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• 2009

The occurrence of toothache signals the malfunction in oral health, which allows the detection of any abnormal condition in the oral cavity at an early stage to prevent the condition from worsening, and thus can act as a preventive measure. This study has looked into the status of oral health management in relation to toothache through the structured survey administered to 235 college students. Based on the survey results, this study aimed at comparing the toothache occurrence prediction between regression analysis and CART model in order to clarify the relationship between the factors of oral health management habits that contribute to toothache occurrence. According to the result, there was a difference between the present health status and the health status of the past year depending on the presence or non-presence of toothache occurrence (p<0.05). There was a difference in the regularity of meal time depending on the presence non-presence of toothache occurrence from the dietary habits of the research subjects (p<0.05). As for the presence or non-presence of toothache occurrence from the oral hygiene habits of the research subject, there was a difference between the occurrence and nonoccurrence of bleeding during brushing or flossing (p<0.05). According to the results of regression analysis, no factors were signifiant in the relationship with the presence or non-presence of toothache occurrence from the status of life habits and oral hygiene habits. 70% of the researched group was randomly selected as the sample for generating an analytical model and the remaining 30% was used as the sample for generating an evaluation model. According to the results of CART model, the occurrence of toothache was higher in the case of irregular meal time and poor current health condition than the case of average or satisfactory health condition. The above results imply that CART model is very useful technique in predicting toothache occurrence compared to regression analysis, and suggests that CART model could be very useful in predicting other oral diseases including toothache.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.42 no.3
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• pp.343-350
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• 2022

High-resolution data are needed to understand water body mixing patterns at river junctions. In particular, in river analysis, hydrological and water quality characteristics are used as basic data for aquatic ecological health, so observation through continuous monitoring is necessary. In addition, since measurement is carried out through a one-dimensional and fixed measurement method in existing monitoring systems, a hydrological and water quality characteristics investigation of an entire river, except for in the immediate vicinity of the measurement point, is not undertaken. In order to obtain high-resolution measurement data, a measurer has to consider multiple factors, and the area or time that can be measured is limited. Although the resolution might be lowered, an appropriate interpolation method must be selected in order to acquire a wide range of data. Therefore, in this study, a high-elevation measurement method at a river junction was introduced, and the interpolation method according to the measurement results was compared. The overall hydraulic and water quality information of the river was indicated through the visualization of the prediction and interpolation method in the low-resolution measurement result. By comparing each interpolation method, Inverse Distance Weighting, Natural Neighbor, and Kriging techniques were applied in river mapping to improve the precision of river mapping through visualized data and quantitative evaluation. It is thought that this study will offer a new method for measuring rivers through spatial interpolation.

• Journal of Science Education
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• v.47 no.1
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• pp.24-36
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• 2023

In this study, we investigated chemistry teachers' the Stage of Concern (SoC) and the Level of Use (LoU) regarding competency assessment, which was emphasized along with the introduction of the 2015 revised curriculum. A questionnaire was developed based on the CBAM, and responses from 123 chemistry teachers were analyzed. The frequency was investigated for both SoC and LoU, and then the chi-square test was performed according to demographic variables. As a result of the SoC analysis, most of the teachers stayed in stage 3 (management concern, 26.8%) and stage 2 (personal concern, 19.5%). Additionally, among the demographic variables, there was a statistically significant difference in whether or not related education experience was present during the pre-service teacher period. In LoU analysis, Level III (mechanical) was the most frequent (26.8%), followed by Level I (orientation, 22.8%), Level II (preparation, 13.8%). In LoU, there was also a statistically significant difference in whether or not related education experience was present during the pre-service teacher period. The Spearman correlation coefficient between SoC and LoU in the competency assessment was .298 and there was a positive correlation. Based on the above results, educational implications for improving the concern and use of chemistry teachers for competency assessment were discussed.