• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.86-92
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• 2017

In this study, a running performance evaluation and roller rig test was conducted to evaluate the applicability of a composite bogie frame, which has the role of the primary suspension. The composite bogie frame was made of a GEP224 glass/epoxy prepreg. Vehicle dynamic analysis was carried out on the composite bogie with three different kinds of side beam thicknesses (50 mm, 80 mm, and 150 mm). From the results, the composite bogie with a side beam thickness of 80 mm satisfied all the dynamic design requirements. Although the composite bogie with the side beam thickness of 50mm also met the design requirements, its critical speed was just a 2% margin to the requirement. In contrast, the model of the side beam thickness of 150mm did not meet the ride comfort. In addition, a composite bogie frame with the side beam thickness of 80 mm was fabricated and installed on a complete bogie. Moreover, the roller rig test using the fully equipped bogie was performed to evaluate the critical speed. During the test, the lateral excitation was imposed on the wheelsets to realize the rail irregularity. There was no divergence of the lateral displacement of the wheelsets while increasing the speed. The measured critical speed was similar to the predicted result.

• Journal of Bio-Environment Control
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• v.30 no.4
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• pp.410-418
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• 2021

This study was conducted in 8.2m wide single-span greenhouse to investigate the effect of presence or absence of rafter steel pipe joint and foundation conditions on greenhouse structural performance. Structural performance was evaluated by static loading test using the structural performance evaluation system for single-span greenhouse. The measured displacement was compared with the predicted result by numerical analysis. The displacement of each measurement location showed a significant difference regardless of the conditions of the foundation and presence or absence of rafter steel pipe joint. Compared to the hinge conditions, the difference in structural performance of the greenhouse in the fixed conditions was seen to be relatively large. The difference in structural performance according to presence or absence of rafter steel pipe joints, the lateral stiffness of the joint was 8.1% greater.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.40-55
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• 2015

This study aims to evaluate the efficiency of the forest experience center for children led by the local community as experiential management for forest kindergarten education. For this, an importance and performance analysis was conducted on the forest experience center for children in Geumcheon-gu, which, of the 12 forest experience center for kids in Seoul, is the only one led by the local community. The questionnaire sheet for the analysis consisted of a total of 36 questions, 20 about place facility areas and 16 about management program areas(including 6 questions about the management led by the local community). The questionnaire survey was done during the period between January 12th and January 19th, 2015. The participants in the survey consisted of 15 forest education specialists and 50 teachers from 19 kindergartens who participated in the forest experience program. The number of questionnaire sheets collected and used for analysis was 13 copies and 43 copies, respectively. The mean values of importance and performance on the place facility areas were 4.07 and 3.78 for forest education specialists, and 4.16 and 3.84 for kindergarten teachers, respectively. The mean values of importance and performance regarding the management program area were 4.38 and 4.16 for forest education specialists, and 4.40 and 4.00 for kindergarten teachers, respectively. Both groups evaluated the place facility areas lower than the management program areas. They also evaluated performance lower than importance. In place facility area, 'accessibility', 'safety' and 'connectivity to forest trail', 'loose parts' and 'safety facilities' were required to 'keep up the good work', because they showed higher importance and performance in place facility areas. Even though most items of management as led by the local community including 'forest experience activity support' were evaluated as 'important', some, including 'effort for local revitalization', were evaluated as low in performance. However, as they were evaluated as higher in importance, if they pursue 'concentrate here', it is expected that they will be evaluated as higher in performance. In addition, considering that program areas including 'forest education specialist's role' are labeled under the management led by the local community, it reflected a positive evaluation. As a result, management led by the local community is efficient as a management system for the forest experience center for children in an experiential forest kindergarten education. Going forward, if this management system is durable in 'keep up the good work' and 'concentrate here', the forest experience center for children led by the local community will be an alternative for an effective experiential forest kindergarten education.

• Journal of Korea Port Economic Association
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• v.34 no.4
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• pp.141-160
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• 2018

In this paper, to analyze the perception and response strategy of Korean ship owners on Global Sulphur Cap 2020, examined the IMO environmental regulation status focusing on MARPOL Annex VI regulation about air pollution prevention, technological measures to reduce SOx emission, shipping industry and management status of Korean ship owners. First of all, the questionnaire was conducted for Korean ship owners after selecting the evaluation factors. The purpose of this study was to investigate the difference of the perception and response strategy of Korean ship owners by corporation size and main vessel type using frequency and cross analysis. It is confirmed that various researches on SOx emission reduction have been carried out from various points of view at home and abroad. In this study, existing studies related to technical factors for regulatory response and economics analysis were examined and evaluation factors were selected. As a result of analysis, it is found that large-sized shipping companies are more prepared for regulatory response than small and medium-sized bulk carrier owners. There were similar perception and the direction of response strategy about the impacts by corporation size and main vessel type. In about two years to be implemented in 2020, It is necessary to find an appropriate response strategy based on the support policy of the government and related organizations and the systematic analysis of the ship owners. Through this study, although the difference between the perception and response strategy of the ship owners by corporation size and main vessel type was understood, it was found that there were limitations on specific response strategy and corporate data collection. In future research, we should overcome the limitations of this study and conduct an in-depth study.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.82-98
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• 2009

This study applied SWAT model to analyze suspended sediment load that is influence on the high density turbid water in Donghyang and Cheoncheon basin, which are located in the upstream of Yongdam Dam. GIS data such as DEM, land cover map and soil map, and meteorological data were used as the input data of SWAT model. And the rating curve equation and Q-SS equation of Donghyang and Cheoncheon gauge station were applied as the measured values of them. As the result of flowout, the coefficient of determination ($R^2$) and the Nash-Sutcliffe coefficient of efficiency (EI) of model calibration showed high as 0.87 and 0.87 at Donghyang gauge station, and the $R^2$ and EI of model validation were high as 0.95 at Cheoncheon gauge station. Also, as the result of suspended sediment load, the $R^2$ and EI of model calibration were high as 0.77 and 0.76 at Donghyang gauge station, and the $R^2$ and EI of model validation marked high as 0.867 and 0.80 at Cheoncheon gauge station. It is considered that the suspended sediment load of 2003 showed the highest due to rainfall amounts and rainfall intensity in using SWAT model. The results of suspended sediment modeled in this study can be applied to the decision-making support data for the evaluation of soil erosion possibility and turbid water potential in the management of reservoir.

• Explosives and Blasting
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• v.30 no.2
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• pp.29-42
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• 2012

Variables influencing the free face movement due to rock blasting include the physical and mechanical properties, in particular the discontinuity characteristics, explosive type, charge weight, burden, blast-hole spacing, delay time between blast-holes or rows, stemming conditions. These variables also affects the blast vibration, air blast and size of fragmentation. For the design of surface blasting, the priority is given to the safety of nearby buildings. Therefore, blast vibration has to be controlled by analyzing the free face movement at the surface blasting sites and also blasting operation needs to be optimized to improve the fragmentation size. High-speed digital image analysis enables the analyses of the initial movement of free face of rock, stemming optimality, fragment trajectory, face movement direction and velocity as well as the optimal detonator initiation system. Even though The high-speed image analysis technique has been widely used in foreign countries, its applications can hardly be found in Korea. This thesis aims at carrying out a fundamental study for optimizing the blast design and evaluation using the high-speed digital image analysis. A series of experimentation were performed at two large surface blasting sites with the rock type of shale and granite, respectively. Emulsion and ANFO were the explosives used for the study. Based on the digital images analysis, displacement and velocity of the free face were scrutinized along with the analysis fragment size distribution. In addition, AUTODYN, 2-D FEM model, was applied to simulate detonation pressure, detonation velocity, response time for the initiation of the free face movement and face movement shape. The result show that regardless of the rock type, due to the displacement and the movement velocity have the maximum near the center of charged section the free face becomes curved like a bow. Compared with ANFO, the cases with Emulsion result in larger detonation pressure and velocity and faster reaction for the displacement initiation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.301-307
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• 2013

This study was evaluated high end research grade Near Infrared Reflectance Spectrophotometer (NIRS) to field grade multiple Near Infrared Reflectance Spectrophotometer (NIRS) for rapid analysis at fresh rice leaf at sight with 238 samples of fresh rice leaf during year 2012, collected Jeollabuk-do for evaluate accuracy and precision between instruments. Firstly collected and build database high end research grade NIRS using with 400 nm ~ 2500 nm during from year 2003 to year 2009, seven years collected fresh rice leaf database then trim and fit to field grade NIRS with 1200 nm ~ 2400 nm then build and create calibration, transfer calibration with special transfer algorithm. The result between instruments was 0.005% differences, rapidly analysis for chemical constituents, Total nitrogen in fresh rice leaf within 5 minutes at sight and the result equivalent with laboratory data. Nevertheless last during more than 8 years collected samples for build calibration was organic samples that make differentiate by local or yearly bases etc. This strongly suggest population evaluation technique needed and constantly update calibration and maintenance calibration to proper handling database accumulation and spread out by knowledgable control laboratory analysis and reflect calibration update such as powerful control center needed for long lasting usage of fresh rice leaf analysis with NIRS at sight. Especially the agriculture products such as rice will continuously changes that made easily find out the changes and update routinely, if not near future NIRS was worthless due to those changes. Many research related NIRS was shortly study not long term study that made not well using NIRS, so the system needed check simple and instantly using with local language supported signal methods global distance (GD) and neighbour distance (ND) algorithm. Finally the multiple popular field grades instruments should be the same results not only between research grade instruments but also between multiple field grade instruments that needed easily transfer calibration and maintenance between instruments via internet networking techniques.

• Journal of Korean Elementary Science Education
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• v.39 no.3
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• pp.382-398
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• 2020

This study aims to analyze the relationship between scientific content knowledge of science-gifted elementary students and their expression of scientific creativity, and the characteristics of divided groups according to the levels of their scientific content knowledge and scientific creativity. A science-gifted program was implemented to 33 forth-graders in the Science-Gifted Education Center of an education office in Seoul, Korea. The method of evaluating scientific knowledge was divided into well-structured paper-pencil test (asking specific and limited range of content knowledge of plants) and ill-structured descriptive test (stating all the knowledge they know about plants) to find out which methods were more related to scientific creativity. In addition, in order to find out the characteristics of each group according to the level of scientific content knowledge and scientific creativity, students were required to answer a questionnaire about their own self-perception of scientific knowledge and scientific creativity and how to obtain scientific knowledge. The main results of this study are as follows. First, Both well-structured paper-pencil test (r=.38) and ill-structured descriptive test (r=.51) results of elementary science gifted students were significantly correlated with scientific creativity. Second, As a result of the regression analysis on scientific creativity of science-gifted elementary students, both the knowledge measured by the two evaluation methods have the ability to explain scientific creativity. Third, the students were categorized into four groups according to the levels of their scientific content knowledge and their expression of scientific creativity, and the result showed that the higher the knowledge of science, the higher the scientific creativity. Fourth, the description about self-perception of scientific knowledge revealed that the highest percentage of Type LL students of all 13 students (53.8%, 7 students) answered 'I have little knowledge of plants because I have little interest in them.' Fifth, the description about self-perception of scientific knowledge revealed that the highest percentage of Type HH students of all 15 students (40%, 6 students) answered 'I think my science creativity is high through my experience of scientific creativity. Sixth, the responses to the Questionnaire revealed that 'reading' was the most popular way to obtain scientific knowledge, with 27 out of total 33 students choosing it. In particular, all 18 students from Type HH (high scientific knowledge and high scientific creativity) and Type HL (high scientific knowledge and low scientific creativity) - those with high scientific knowledge - gave that response. On the basis of this research, we should explore practical teaching methods and environment for gifted students to improve their scientific creativity by revealing the nature of the factors that affect scientific creativity and analyzing relationship between knowledge and scientific creativity.

• Journal of Oriental Neuropsychiatry
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• v.24 no.1
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• pp.45-62
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• 2013

Objectives : The purpose of this study was to compare the efficacy of Needle-Embedding Therapy with Acupuncture for Chronic Tension-type Headache (CTTH) patients. Methods : The study recruited Chronic Tension-type Headache patients. A total of twenty-six patients were divided into 2 groups. 13 subjects were placed into a needle-embedding therapy group and 13 subjects into an acupuncture therapy group by a randomization table. The needle-embedding therapy group was treated with needle-embedding at Fengchi (GB20), while the acupuncture therapy was acupunctured at Fengchi (GB20). Then, a comparative analysis was conducted by comparing the results with those measured by a Blood pressor, Heart rate variability (HRV), Henry Ford Headache Disablity Inventory (HDI) Internet Headache Impact Test (HIT), and Visual Analogue Scale (VAS). Results & Conclusions : As a result of evaluation by using the self-rating headache index (VAS, HDI, HIT), pain score declined in both groups. But they were not difference between the two groups.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.300-304
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• 2016

The aim of this study were to evaluate the exposure level of pyrethroid pesticide according to spraying machine type. The urinary metabolites of pyrethroid pesticide in apple farmers were analyzed to determine the exposure level of pyrethroid pesticide. The result shows that, the spraying volume was greater in SS sprayer group than in power sprayer group. But multi variate analysis which adjust spraying volume and field area, there were no difference of urinary metabolites between two sprayer machine. To make more accurate model of pesticide exposure, the factors influencing pesticide exposure should be determined and further study should be done.