• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.31-36
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• 2009

This study was conducted to find out an alternative way of rapid and accurate analysis of forage quality. Near reflectance infrared spectroscopy (NIRS) was used to evaluate the possibility of forage analysis and collect 258 samples such as barley for whole crop silage, forage corn and sudangrass from 2002 to 2007. The samples were analyzed for CP (crude protein), CF (crude fiber), ADF (acid detergent fiber), NDF (neutral detergent fiber) and IVTD (in vitro true digestibility), and also scanned using NIRSystem with wavelength from $400{\sim}2,400nm$. Multiple linear regression was used with wet analysis data for developing the calibration model and validate unknown samples. The important index In this experiment was SEC and SEP $r^2$ for CF, CP, NDF, ADF and IVTD in calibration set were 0.70, 0.86, 0.94, 0.94 and 0.89, also 0.47, 0.39, 0.89, 0.90 and 0.61 in validation sample, respectively. The results of this experiment indicates that NIRS was reliable analytical method to assess forage quality, specially in CF, ADF and IVTD, sample should be included for respective forage samples to get accurate result. More robust calibrations can be made to cover every forage samples if added representative sample set.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.489-496
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• 2019

This paper is a study on the evaluation of loss factor of damping treatment materials to reduce the noise and vibration for panels of railway vehicles and automobiles. In order to determine the modal parameters of damping materials, beam excitation tests were carried out using different type PVC coated aluminum and steel base beam specimens. The specimens were excited from 10 Hz to 1000 Hz frequency range using sinusoidal force, and transfer mobility data were measured by using an accelerometer. The loss factors were determined by using integrated program, based on theories of Half Power Method, Minimum Tangent Error Method, Minimum Angle Error Method and Phase Change Method, which enable to evaluate the parameters using modal circle fit and least squares error method. In the case of lower loss factor and data of linear characteristics, any method could be applied for evaluation of parameters, however the case of higher loss factor or data including non-linear characteristics, the minimum angle error method could reduce the loss factor evaluation. The obtained dynamic properties of the coating material could be used for application of Finite Element Method analyzing the noise control effects of complex structures such as carbody or under-floor boxes of rolling stock. The damping material will be very useful to control the structural noise, because the obtained modal loss factors of each mode show very good effect on over $2^{nd}$ mode frequency range.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.4119-4125
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• 2012

The purpose of this study was to identify the validity, reliability, and discriminative index of the Korean version of Modified Barthel Index (K-MBI). For this, two hundreds twenty-thee stroke patients participated. Activities of daily living were measured through using K-MBI. Factor analysis was performed for identifying the construct validity and internal consistent and discriminative index were calculated. The result of factor analysis was that the 10 items of K-MBI have communality above .50, and was constructed one factor. Explained variance was 72.184%. The order of factor loading value was toileting, personal hygiene, transfer from bed to chair and back, ambulation/wheelchair, dressing, feeding, bowel control, bathing, bladder control, and stair climbing. Cronbach ${\alpha}$ of K-MBI was .994. The range of discriminative index was .783~.909, and was acceptable. One factor of K-MBI was identified through factor analysis, and reliability and discriminative index was also identified. Various psychometric properties of K-MBI should be investigated in further studies for valid assessment of activities of daily living in stroke patients.

• Journal of Science Education
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• v.41 no.3
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• pp.382-404
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• 2017

This study aims to explore a learning progression for eight core concepts of middle school science using constructed response items in the national assessment of educational achievement (NAEA). For this purpose, a total of 7,390 responses of the 9th graders on 8 constructed response items in NAEA conducted in 2015 were inputted by computer and the inputted answers were analyzed and classified into different levels. After completing this process, five levels were set for each construct and a construct map was created according to the levels. In this study, the construct map was written in a progression-based rubric format, which was used as a criterion for leveling the answers of all students. In addition, the Rasch model was applied to measure the scores and achievements of the respondents by means of statistical analysis to correlate the scores of the students with the achievement levels of the constructs. Lastly, a preliminary learning progression was created by revising the construct map reflecting the results of Rasch model application. This study was meaningful in that it explored the possibility of developing the learning process by using constructed response items in NAEA. However, the preliminary learning progression developed in this study is still hypothetical and inferential because it is not longitudinally traced to individual students. Therefore, it is necessary to continually revise and supplement through iterative research process.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.1
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• pp.13-18
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• 2008

This experiment was conducted to compare the agronomic characteristics, flowering condition and productivity of introduced annual legumes at paddy field of Seonghwan(Cheonan, Chungnam, Korea) from September 2006 to May 2007. Annual legumes used in this study were hairy vetch(Vicia villsa, Rosa), crimson clover(Trifolium incarnatum, Contea), berseem clover(Trifolium alexandrinum, Alexandria), persian clover(Trifolium resupinatum, Prolific), balansa clover(Trifolium michelianum, Paradona), sweet clover(Melilotus officinalis, Yellow) and forage pea(Pisum sativum, Austrian). Emergency rate after seeding were 90% or more in crimson clover, hairy vetch, forage pea and berseem clover. Wintering of hairy vetch and crimson clover were excellent as 98% and 95%, respectively. Flowering rate of harvesting date(May 10) was 100% in crimson clover, 98% in balansa clover, 5% in persian clover and others were not flowering. Fresh and dry matter yield of crimson clover were highest as 72,556 kg/ha and 16,062 kg/ha, respectively. Crude protein yield of hairy vetch was highest as 2,929 kg/ha but not significant with crimson clover(2,169 kg/ha). TDN yield of crimson clover was highest as 9,007 kg/ha but not significant with hairy vetch(7,366 kg/ha). According to the results from this study, it is suggested that crimson clover would be recommendable for autumn-sowing annual legume at paddy field of Central Provinces.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.9
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• pp.917-922
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• 2005

The wastewaters from textile and dyeing industries are difficult to treat due to its high pH, temperature, color intensity and non-biodegradable organic contents. This study investigated the removal of recalcitrant organics in a dyeing wastewater by using a packed bed reactor (PBR) that contained cell-immobilized pellets. The feed, obtained from an effluent of a biological treatment plant, had $SCOD_{Cr}$ of 330 mg/L and $SBOD_5$ of 20 mg/L on average. In immobilizing the cells to a Polyethylene Glycol(PEG) based medium, activated sludges from either a sewage treatment plant or an industrial wastewater treatment plant were used. When the empty bed contact time (EBCT) was above 8 hrs in the PBR, the $COD_{Cr}$ removal efficiency was over 50% and the $COD_{Mn}$ concentration was 72 mg/L or lower on average, which was substantially lower than the discharge standard of 90 mg/L. The results indicated that the optimum EBCT in the PBR was 8 hrs. The PBR with cell-immobilized pellets was effective as an advanced treatment process after an activated sludge process for treating dyeing wastewaters.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.4
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• pp.316-325
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• 2009

Technical design codes of slope stability for port structures were studied by comparing local Korean code with international codes; Japanese, EC and China codes. Three international design codes are based on limit state design method. Although Chinese code was based on the modified Fellenius method in slope stability analyses, it is currently changing to the simplified Bishop method. In Eurocode, the Morgenstern & Price method or the Bishop method is recommended. In Japanese code, however, the modified Fellenius method is preferentially recommended, but the simplified Bishop method could be alternatively used in case of thick sandy ground conditions. As for design parameter determination, Eurocode has stipulated comprehensive partial factors and partial material factors, however Japanese code has clarified empirical partial material factors for each port structure. Chinese code, the minimum ranges of the comprehensive partial factors are stipulated, and the use of the strength index by specific tests is concretely clarified with the safety condition. Case study of slope stability analyses showed the safety factors were higher in order of Chinese, Japanese and Eurocode, respectively.

• Journal of Korean Society of Transportation
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• v.31 no.3
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• pp.19-32
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• 2013

The study aims to find the characteristics of children's crossing behavior on crosswalk in school zones. It considers accident occurrence and physical form of school zones. Seven elementary school zones were investigated. Using data collected by field observation and video recording, statistical analysis, CHAID algorithm analysis, and pattern analysis were performed. As a result, it was found that children's waiting, attention and distraction were related to the accident occurrence. While 69.1% children showed waiting-before-crossing behavior in low-accident occurrence crosswalk, 83.6% children showed non waiting-before-crossing behavior in high-accident occurrence crosswalk. Moreover, the ratio of waiting, attention behavior was found to be higher when the width of the crosswalk was wide and the distance from the school's entrance to the crosswalk was long. These research findings showed that children's behavior-oriented approach was required to improve safety in school zone.

• Journal of the Korean Chemical Society
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• v.55 no.6
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• pp.1030-1041
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• 2011

We investigated the understanding of pre-service science teacher about the chemistry concept of middle school curriculum using some items in National Assessment of Educational Achievement and analyzed the result according to background variables of pre-service science teacher. The result was that there were some pre-service science teachers who select incorrect answer at all items, pre-service science teachers don't fully understand the concept needed to solve item. And the percentage of correct answer at some items was low regardless of selection of chemistry as an elective subject at CSAT(College Scholastic Ability Test). We found some facts through the depth interviews to find the cause of the result. First, the misconception acquired in middle school days is tend not to change until college student. Second, the formation of misconception is affected by the study habit with which solve problem by simple calculation and memory without essential understanding. Third, the study habit with which solve problem by simple calculation and memory without essential understanding could not replace misconceptions acquired in middle school days with scientific concept regardless of selection of chemistry as an elective subject at CSAT.

• Journal of the Korean Chemical Society
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• v.64 no.5
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• pp.277-290
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• 2020

In this study, four gifted students in the second year of middle school at Gifted Education Center of the National University in Jeollanam-do were surveyed students' perceptions of the effectiveness of science class using science writing heuristic in terms of metacognition and the goals of the 2015 revised science curriculum. Through questionnaires and interviews with gifted science students, science gifted students recognized that the science class using science writing heuristic had a positive effect on the four subdomains (planning, monitoring, control, and evaluation) of metacognition. For this reason, the science gifted students presented self-directed experience in designing experiments, continually checking the collected experimental data, feedback process, and reflecting experience in preparing conclusions. Science gifted students recognized that science class using science writing heuristic had a positive effect on the goals of the 2015 revised science curriculum(attitudes, inquiry, knowledge, Science·Technology·Society(STS), and the enjoyment and usefulness of science learning) that correspond to through inquiry science writing lessons. For this reason, the science gifted students presented self-directed inquiry experiences, continual inquiry experiences on the same subject, thinking process at each stage of inquiry, learning experiences through inquiry, experience of the whole inquiry process, and inquiry of phenomena closely related to real life. Therefore, for the effective science class, it is necessary to apply the characteristics of science class using science writing heuristic which is responded by science gifted students to general science class as well as science gifted class later.