• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.272-278
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• 2018

Traffic volume has been greatly increasing due to urban development and the improvement of living standards, and many complaints are being raised due to the increasing road noise. As a countermeasure against these problems, highly soundproof walls are installed on the sides of roads. However, the ability to bear wind loads is a major design requirement for soundproof walls, which contributes to the exponential increases in construction costs and restricts the height of the walls. The aim of this study is to improve the performance of soundproof walls and to dramatically reduce wind loads while maintaining excellent price competitiveness. Based on Helmholz's resonator theory, a new concept is proposed for a ventilation-type soundproofing plate that can pass through a fluid like air and reduce noise. A full-scale metal soundproofing plate was produced to satisfy the quality standards of highways by conducting a sound-pressure transmission-loss test, wind tunnel test, and material quality test. To verify the reliability, the wall was manufactured and installed, and the sound insulation effect was examined by measuring the noise over time. In the future, ventilated soundproof walls on roads could create a pleasant living environment due to the high noise-insulation effect.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.438-443
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• 2022

In this study, the lateral loading test was performed to analyze structural performance of multi-span plastic greenhouse through full-scale experiment and numerical analysis. In order to analyze the lateral stiffness and stress, we installed 9 displacement sensors and 19 strain gauge sensors on the specimen, respectively, and load of l mm per minute was applied until the specimen failure. In the comparison between the full-scale experiment and the structural analysis results of a multi-span greenhouse with venlo-type roof according to bracing installation, there was a large difference in the lateral stiffness of the structure. By installing a brace system, the lateral stiffness measured near the side elevation of the specimen increased by up 44%. As the bracing joint used in the field did not secure sufficient rigidity, the external force could not be transmitted to the entire structure properly. Therefore, it is necessary to establish a bracing construction method and design standards in order for a greenhouse to which bracing applied to have sufficient performance.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.2
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• pp.171-182
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• 2022

InSAR (Interferometry SAR) technique is a technique that uses complex data to obtain phase difference information from two or more SAR image data, and enables high-resolution image extraction, surface change detection, elevation measurement, and glacial change observation. In many countries, research on the InSAR technique is being conducted in various fields of study such as volcanic activity detection, glacier observation in Antarctica, and ground subsidence analysis. In this study, a case of large ground settlement due to groundwater level drawdown during tunnelling was introduced, and ground settlement analyses using InSAR technique and numerical analysis method were compared. The maximum settlement and influence radius estimated by the InSAR technique and numerical method were found to be quite similar, which confirms the reliability of the InSAR technique. Through this case study, it was found that the InSAR technique reliable to use for estimating ground settlement and can be used as a key technology to identify the long-term ground settlement history in the absence of measurement data.

• Korean Journal of Remote Sensing
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• v.37 no.2
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• pp.211-220
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• 2021

Land Surface Temperature (LST) is one of the useful parameters to diagnose the growth and development of crop and to detect crop stress. Unmanned Aerial Vehicle (UAV)-based LST (LSTUAV) can be estimated in the regional spatial scale due to miniaturization of thermal infrared camera and development of UAV. Given that meteorological variable, type of instrument, and surface condition can affect the LSTUAV, the evaluation for accuracy of LSTUAV is required. The purpose of this study is to evaluate the accuracy of LSTUAV using LST measured at ground (LSTGround) under various meteorological conditions and growth phases of garlic crop. To evaluate the accuracy of LSTUAV, Relative humidity (RH), absolute humidity (AH), gust, and vegetation index were considered. Root mean square error (RMSE) after minimizing the bias between LSTUAV and LSTGround was 2.565℃ under above 60% of RH, and it was higher than that of 1.82℃ under the below 60% of RH. Therefore, LSTUAV measurement should be conducted under the below 60% of RH. The error depending on the gust and surface conditions was not statistically significant (p-value < 0.05). LSTUAV had reliable accuracy under the wind speed conditions that allow flight and reflected the crop condition. These results help to comprehend the accuracy of LSTUAV and to utilize it in the agriculture field.

• Korean Journal of Culture and Social Issue
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• v.28 no.2
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• pp.107-131
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• 2022

This study was conducted with the aim of developing and validating a measure of the workplace bullying bystander behavior. For the purpose, items were developed by referring to previous studies related to workplace bullying, and behavior subtypes were defined as pro-bullying, defending, and bystander behaviors. After confirming the content validity with the help of experts, a total of 31 preliminary items were composed. The final 26 items were selected by conducting an exploratory factor analysis and verifying the validity and reliability of the scale with a survey of 288 office workers who have directly or indirectly witnessed workplace bullying over the past three years. In this process, it was confirmed that defense behavior was distinguished into two types: Active and supportive. Confirmatory factor analysis was conducted with data from 518 office workers who have directly or indirectly witnessed workplace bullying over the past year, and the validity and reliability of the developed scale were confirmed. As a result of comparing the competing models to reconfirm the subtypes, it was confirmed again that active defense behavior and supportive defense behavior were distinguished. The criterion-related validity of all subtypes was confirmed by setting the criterion variables for workplace bullying behavior, altruistic behavior, pro-social behavior, fear of intervention, moral disengagement, guilt, and moral identity. Based on the result of this study, follow-up research tasks related to workplace bullying bystander behavior scale were suggested and the methods to prevent and intervene in workplace bullying while utilizing workplace bullying bystander behaviors were discussed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.4
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• pp.274-284
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• 2022

To use kenaf (Hibiscus cannabinus L.) as a fiber and livestock feed, a high-yielding variety needs to be identified. For this, accurate phenotyping of plant height is required for this breeding purpose due to the strong relationship between plant height and yield. Plant height can be estimated using RGB images from unmanned aerial vehicles (UAV-RGB) and photogrammetry based on Structure from Motion (SfM) algorithms. In kenaf, accurate measurement of height is limited because kenaf stems have high flexibility and its height is easily affected by wind, growing up to 3 ~ 4 m. Therefore, we aimed to identify a method suitable for the accurate estimation of plant height of kenaf and investigate the feasibility of using the UAV-RGB-derived plant height map. Height estimation derived from UAV-RGB was improved using multi-point calibration against the five different wooden structures with known heights (30, 60, 90, 120, and 150 cm). Using the proposed method, we analyzed the variation in temporal height of 23 kenaf cultivars. Our results demontrated that the actual and estimated heights were reliably comparable with the coefficient of determination (R²) of 0.80 and a slope of 0.94. This method enabled the effective identification of cultivars with significantly different heights at each growth stages.

• Korea Trade Review
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• v.42 no.2
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• pp.319-344
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• 2017

The international standard certification evaluates the extend to which the supplier satisfies the international standard certification standards of the supplier of the product and the service, recognizes the quality assurance ability and reliability of the supplier, thereby resolving the international trade regulation that can occur to various fields and strengthening the network of the global partnership it is making an important contribution. Therefor, in this study, the survey was conducted on 153 companies of Korean import and export companies. The research method was empirically analyzed by the structural equation model. The results of the hypothesis test of this study are as follows. First, resource management factors among the international standard certification factors in the global trade supply chain integration had a positive effects on CRM satisfaction. Second, the measurement, analysis and improvement factors of international standard certification factors had a positive effects on CRM satisfaction. Third, CRM satisfaction has a positive effects on business performance. Through this study, it is concluded that the Korean import and export companies have an important role in improving the business performance of the global trade partners.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.426-426
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• 2022

하천에서 유사량은 침식(Erosion), 유송(Transport), 퇴적(Deposition)의 3단계 과정으로 진행되며 이 과정에서 다양한 유사 문제가 수반되고 있다. 특히, 하상변동의 예측, 하천계획 수립 등 수자원 개발을 위해 유사량 조사는 반드시 필요하다. 따라서 국외에서는 오래전부터 하천 유사이송과정에 대한 이론적인 개념을 정립하고 양질의 유사량 자료를 위해 연구해 오고 있다. 국내에서는 대표적으로 한국수자원조사기술원에서 유사량조사 업무를 수행하고 있으며 국가유사량관측망 중 매년 약 20개소~30개소의 지점을 대상으로 신뢰성 있는 자료를 만들기 위해 지속적으로 연구하고 있다. 유사량 조사의 항목 중 부유사 채취를 위한 측선수는 하천 폭(ISO 기준)에 따라 5개~7개의 측선에서 부유사를 채취하고 있으며, 강우가 활발한 홍수기 전, 후로 단면측량 및 하상토 자료를 통해 총유사량을 산정하고 있다. 본 연구의 분석방법으로는 이신재(2021)가 제안한 방법을 착안하였고, 측선별 부유사농도와 평균부유사농도의 비교분석 통해 상관계수(R²)가 가장 높은 측선을 선택하여 지표부유사량(Index Suspended Sediment) 산정에 활용하였다. 대상지점으로는 연속 유사량 자료 생산이 가능한 낙동강유역의 함안군(계내리) 관측소와 영산강유역의 구례군(구례교) 관측소를 선정하였다. 먼저, 지표 유사량은 평균부유사농도와 측선별 부유사농도를 비교분석하였으며, 함안군(계내리) 관측소는 5번 측선(R²=0.9869), 구례군(구례교) 관측소는 2번 측선(R²=0.9929)을 통해 지표부유사량을 산정하였다. 그 결과 하천특성에 따라 측정된 부유사량과 지표부유사량의 편차율(함안군(계내리) : 최대 33%, 최소 1%, 구례군(구례교) : 최대 25%, 최소 1%)이 다소 상이한 구간이 발생하였지만 이들의 상관계수(R²)는 각각 0.9922, 0.9947로 매우 높게 산정되었다. 이러한 결과를 통해 제시한 지표 설정은 실제 업무에서 활용 가능할 것으로 판단되며, 추후 과거년도의 하천특성과 수리특성 분석을 통해 해당지점의 대표적인 측선을 선정해 연속적인 지표 유사량 자료 생산이 가능하다면 향후 자동 유사량 채수장치 설치를 통해 안정된 유사량 자료 제공이 가능할 것으로 기대된다.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.671-680
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• 2022

This study evaluated the consistency between the web-based and paper-based mibyeong and cold-heat pattern questionnaire, the Korean medicine-based tool for diagnosing and classifying health status. First, a web-based survey was conducted on 72 ordinary people; subsequently, a paper-based survey was conducted after a certain time interval. The equivalence between the web-based and paper-based surveys was evaluated on the basis of the consistency between scores using the Intraclass Correlation Coefficient (ICC) and Bland-Altman methodology. The mibyeong questionnaire showed high reliability for the web-based and paper-based surveys (ICC=0.95, 95% CI 0.92 - 0.97), and the cold-heat pattern questionnaire showed high reliability for both cold syndrome (ICC=0.98, 95% CI 0.96 - 0.99) and heat syndrome (ICC=0.9, 95% CI 0.83 - 0.93). The difference in average scores between the two survey methods was -0.25 for the mibyeong survey, -0.17 for the cold syndrome, and 0.11 for the heat syndrome, showing a similar pattern. Among the respondents, 84% showed positive satisfaction with the web-based survey, and 80% preferred the web-based survey. Overall, this study confirmed the reliability and feasibility of the web-based survey methods for the mibyeong and cold-heat pattern questionnaire. This could be a useful tool for the follow-up of subjects in long-term cohort studies.

• Korean Journal of Health Psychology
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• v.19 no.3
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• pp.711-727
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• 2014

The purpose of this study was to develop and standardize the Korean version of the Parent Mealtime Action Scale(K-PMAS). The parents of typically developing preschool and elementary school children (N=887) ranging in age from 1 to 11 years as well as parents of children with developmental disorders (N=116) completed the PMAS. A subset of the participants were retested for reliability and also completed the Children's Eating Behavior Inventory- Korean Version (K-CEBI), which was used for assessing validity. The confirmatory factor analysis revealed that the theoretically-based 8-factor structure of PMAS fit the data well. The PMAS scores suggested acceptable levels of internal consistency and test-retest reliability. Validity was also supported by significant correlations between the K-CEBI scores and the differences in K-PMAS scores between the parents of children with developmental disorders and those of typically developing children. The results of one-way ANOVA showed no significant differences in K-PMAS scores between the genders. However, there were significant differences across ages. The means and standard deviations of the PMAS scale scores are provided. Clinical and research implications as well as limitations are discussed.