• Journal of The Korean Association For Science Education
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• v.35 no.5
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• pp.919-929
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• 2015

This study aims to develop a modeling-based learning program about geologic structures and to reveal the relationship between the argumentation patterns and levels of students' mental models. Participants included 126 second grade high school students in four sessions of modeling-based learning regarding continental drift, oceanic ridges, transform faults, and characteristics of faults. A modeling-based learning program was implemented in two classes of the experimental group, and teacher-centered traditional classes were carried out for the other students in the comparison group. Science achievement scores and the distribution of students' mental models in experimental and comparison groups were quantitatively compared. The video-taped transcripts of five teams' argumentation were qualitatively analyzed based on the analytic framework developed in the study. The analytic framework for coding students' argumentation in the modeling-based learning was composed of five components of TAP and the corresponding components containing alternative concepts. The results suggest that the frequencies of causal two-dimensional model and cubic model were high in the experimental group, while the frequencies of simple two-dimensional model and simple cross sectional model were high in the comparison group. The higher the frequency of claims, an argumentation pattern was proven successful, and the level of mental model was higher. After the rebuttal was suggested, students observed the model again and claimed again according to new data. Therefore, the model could be confirmed as having a positive impact on students' argumentation process.

• 재활복지
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• v.20 no.3
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• pp.125-139
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• 2016

The aim of this study was to distinguish 3 concepts(capacity, capability, and performance) for the motor activities of children with cerebral palsy(CP) and examinate relation between capacity(can do in a standardized environment), capability(can do in daily environment), and performance(does do in daily environment). Cross-sectional analysis with a assessment record of children with CP (n=40; 19males, 21 females; mean age 6y 6mo, SD 3y 8mo) was performed. Levels of severity according to the Gross Motor Function Classification System(GMFCS) included level1(13%), level2(10%), level3(43%), level 4(33%), and level 5(3%). Motor activities capacity was assessed by the Gross Motor Function Measure (GMFM-66). Capability and performance were assessed using 2 scales(functional skill, caregiver assistance) of the Pediatric Evaluation of Disability Inventory(PEDI). Correlations between capacity and capability was 0.811(p < .05), and between capability and performance were high(r=0.711, p < .05). And the correlation between capacity and performance is the lowest(r=0.711, p < .05). Motor performance levels are only partly reflected by the motor capacity and motor capability levels in children with CP. Because performance is influenced by Contextual factors (particularly, social factors such as family function). This study suggests that it is necessary to distinguish and evaluate the capacity, capability, and performance in children with cerebral palsy.

• Journal of the Korea Convergence Society
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• v.9 no.3
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• pp.211-216
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• 2018

The study provided basic data that could be used for future research by identifying trends in the factors that affect the multicultural acceptability of Korean teens from 2008 to 2017. Research methods have searched for papers using keywords from 'Multicultural', 'Youth', 'Middle School Student', 'High School Student' and 'Acceptance' in academic data base. As a result of analysis, journal articles and dissertations soared as of 2012, and the academic field identified the largest number of studies being carried out in the field of social science and pedagogy. Quantitative research and cross-sectional study were the most important methods of previous research. On the other hand, few studies have concurrently analyzed new factors related to multicultural acceptability. The results of this study indicate the need for a combined analysis of the new factors that may affect the multicultural acceptability of adolescents.

• Journal of Korean Society of Forest Science
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• v.112 no.1
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• pp.83-92
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• 2023

This study was established to investigate the site environment of mixed forests in Korea and to estimate the growth and yield of stands using national forest resources inventory data. The growth of mixed forests was derived by applying the Chapman-Richards model with diameter at breast height (DBH), height, and cross-sectional area at breast height (BA), and the yield of mixed forests was derived by applying stepwise regression analysis with factors such as cross-sectional area at breast height, site index (SI), age, and standing tree density per ha. Mixed forests were found to be growing in various locations. By climate zone, more than half of them were distributed in the temperate central region. By altitude, about 62% were distributed at 101-400 m. The fitness indexes (FI) for the growth model of mixed forests, which is the independent variable of stand age, were 0.32 for the DBH estimation, 0.22 for the height estimation, and 0.18 for the basal area at breast height estimation, which were somewhat low. However, considering the graph and residual between the estimated and measured values of the estimation equation, the use of this estimation model is not expected to cause any particular problems. The yield prediction model of mixed forests was derived as follows: Stand volume =-162.6859+6.3434 ∙ BA+9.9214 ∙ SI+0.7271 ∙ Age, which is a step- by-step input of basal area at breast height (BA), site index (SI), and age among several growth factors, and the determination coefficient (R²) of the equation was about 96%. Using our optimal growth and yield prediction model, a makeshift stand yield table was created. This table of mixed forests was also used to derive the rotation of the highest production in volume.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.125-135
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• 2022

In this study, growth changes of the diameter at breast height (DBH), height, basal area, volume, and biomass of Korean white pine (Pinus koraiensis Siebold & Zucc.) on a plantation were examined via long-term monitoring. In addition, this study was performed to provide the basic data for timber production in line with DBH class by comparing the growth of the relative DBH size. Growth characteristics according to DBH class were analyzed by categorizing trees into five classes based on sorted DBH rankings: class I (1%-20%; upper 20%), class II (21%-40%), class III (41%-60%), class IV (61%-80%), class V (81%-100%; lower 20%). A total class (0%-100%) was also used. Total increment and mean annual increment (MAI) were calculated using data from nine measurements taken over 39 years. Tree characteristics based on average values and stand characteristics based on unit area per hectare were examined. According to the total increments of variables, the differences in DBH, basal area, volume, and biomass among classes I-V increased over time, whereas the height difference did not continually increase. According to MAI, the maximum DBH value was 0.92 cm·yr^-1 at age 23 in class I, whereas the maximum value in all trees was 0.69 cm·yr^-1 at age 17. The maximum value of height MAI for class I was 0.52 m·yr^-1 at age 23, whereas that for all trees was 0.49 m·yr^-1 at age 20. In terms of basal area, volume, and biomass growth at tree-and stand-level, the maximum MAI of class I and all trees was not observed during the measurement period. Therefore, additional long-term monitoring data are required to determine the maximum MAI of the variables.

• Proceedings of the KAIS Fall Conference
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• 2010.11b
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• pp.1000-1004
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• 2010

본 연구는 도시지역 1개 초등학교 5 6학년과 농촌지역 일개 군의 2개 초등학교 5 6학년을 대상으로 도시와 농촌 초등학교 5 6학년의 변비 유병률을 파악하고, 이와 관련된 배변행태, 식습관 및 운동 습관 요인, 스트레스 등을 분석하여, 학생들이 바람직하고 올바른 생활습관을 갖도록 하고 학생들의 변비 증상을 개선하고 예방하여 건강증진을 도모하는 기초자료로 활용하고자 시도된 단면조사연구이다. 연구대상자는 임의 추출방법에 의하여 선정된 3개 초등학교 5 6학년 재학생 총 585명을 대상으로 하였다. 연구방법은 2009년 10월에 임의로 선정된 3개 학교의 보건선생님을 통하여 연구대상자에게 설문지를 배포하여 대상자 스스로 기입하도록 하였다. 본 연구의 결과로 자가보고에 의한 변비의 유병률은 전체 22.1%로 남학생 16.9%, 여학생 27.0% 이었으며, 주중 3회 미만의 배변횟수를 변비로 정의하였을 경우 변비 유병률은 15.7%로 남학생 11.6%, 여학생 19.6%로 여학생의 변비 발생률이 높았다. 거주지역별로는 농촌 지역에 거주하는 대상자가 도시 지역에 거주하는 대상자보다 변비 발생이 높은 것으로 나타났으며 변비발생과 운동습관과의 관계에 있어서는 운동을 하지 않는 대상자가 변비 유병율이 높게 나타났다. 변비 분류에 의한 배변습관에서는 변비군에서 배변 시간이 10분 이상이 많았으며, 시험기간 중 변비경향 또는 변을 보지 못 한다가 정상군보다 높게 나타났다. 또한, 변비군의 치료관련 행태에서는 18.3%가 변비치료를 위해 변비약을 복용한 경험이 있는 것으로 조사되었으며, 배변 형태에 변화가 있을 경우 상담자로는 가족 또는 혼자 판단하는 경우가 대부분이었다. 변비 분류에 의한 배변 관련 증상의 분포는 변비군에서 항문통증 경험, 항문 출혈 경험 등이 정상군보다 높게 나타났다. 주중 3회 미만의 배변횟수를 변비로 정의 하였을 경우와 배변 관련 증상의 분포는 변비군에서 항문통증 경험, 배변 후 상쾌하지 못함 등이 정상군보다 높게 나타났다. 학교에서의 배변여부는 변비군에서 학교에서 배변을 하는 비율이 정상군보다 높았다. 변비여부를 종속변수로 하여 변비발생에 영향을 미치는 요인을 분석한 결과 성, 학년, 거주지역에서 변비발생의 위험요인으로 도출되었다. 주 3회 미만의 배변횟수를 변비라고 정의할 경우, 변비발생에 영향을 미치는 요인을 분석한 결과 성, 학년, 모직장 유무, 운동이 변비발생의 위험요인으로 도출되었다. 본 연구에서는 초등학교 5 6학년을 대상으로 배변 행태, 식습관, 스트레스, 학교에서의 배변습관 등을 조사해 본 결과 상당수 학생들의 배변 실태가 좋지 않은 것을 알 수 있었다. 바람직하지 않은 식습관, 운동 부족, 과다한 스트레스 등은 학생들의 변비 발생의 위험 요인이 될 수 있으므로 변비의 발생을 예방하기 위해서는 매일 적절한 운동을 하고 인스턴트음식과 패스트푸드섭취 등을 줄이고 올바른 생활습관 및 스트레스 관리 등이 필요하며 부모들의 자녀에 대한 관심이 더욱 필요하다. 이를 위해서 초등학교부터 변비 예방을 위한 체계적인 프로그램을 만들고, 실시하여야 하며 또한 보건교육을 통하여 건강한 생활습관을 습득하고 변비를 예방하는 노력이 필요하다 하겠다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.12
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• pp.1573-1579
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• 2013

To test the performance of nuclear fuels, coolant needs to be circulated through the test rig installed in the test loop. Because the pressure and temperature of the coolant is 15.5 MPa and $300^{\circ}C$ respectively, coolant sealing is one of the most important processes in fabricating a nuclear fuel test rig. In particular, 15 instrumentation cables installed in a test rig pass through the pressure boundary, and brazing is generally applied as a sealing method. In this study, an induction brazing system has been developed using a high frequency induction heater including a vacuum chamber. For application in the nuclear field, BNi2 should be used as a paste, and optimal process variables for Ni brazing have been found by several case studies. The performance and soundness of the brazed components has been verified by a tensile test, cross section test, and sealing performance test.

• Journal of Korean Society of Forest Science
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• v.111 no.1
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• pp.100-107
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• 2022

Quercus mongolica is an important deciduous tree species in the Republic of Korea; it covers most of the total natural deciduous forest area in the country. In this study, the site characteristics and stand structure of Q. mongolica forests were investigated at sites where Q. mongolica occupied >50% of the total basal area during the 7th National Forest Inventory period (2016-2020). The total number of circular sample plots (400 m²) of Q. mongolica forests was 1,421. These forests were mainly dominant at >800 m above sea level (a.s.l). However, they were also distributed on north-facing slopes at <600 m a.s.l. and gradually on southern slopes with ascending altitudes. Quercus mongolica forests were distributed in silt loam, loam, or sandy loam soils with relatively high fertility. Dominant species distributed with Q. mongolica included Pinus densiflora, Quercus variabilis, Acer pseudosieboldianum, Fraxinus rhynchophylla, and Quercus serrata. Pinus densiflora and Q. variabilis grew in large DBH classes, Q. serrata grew in middle DBH classes, and A. pseudosieboldianum and F. rhynchophylla grew in small DBH classes. The dominant species distributed at the lower layer of Q. mongolica forests were Sasa borealis, Lindera obtusiloba, Rhododendron mucronulatum, Rhododendron schlippenbachii, Q. mongolica, and Fraxinus sieboldiana.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.5
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• pp.94-100
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• 2017

In the case of the side scan sonar operated by the towing method, the underwater structure electric jig was developed because there is a difficulty in the cross-sectional survey that the user wants when conducting the survey. However, in the case of the sound wave photographing method using the electric jig, since the boat and the sonar behaves as one body, data distortion has occurred due to various problems according to working environment, such as, the rolling phenomenon of the boat due to the wave and the fluctuation of the sonic image due to the inoperability of the boat driver. Therefore, in order to solve the image blurring caused by the operation of the equipment for underwater survey of the existing side scan sonar, in this research, the program was supplemented to enable the shake correction by attaching the shake correction sensor and developing the shake correction algorithm. In order to verify the improvement of the sonar data resolution, the sonic images before and after the shake correction were collected through on-site investigation and the analysis of the sonic image data acquired by a diver measuring the actual damage length and depth. This study is expected to contribute to the development of sonar imaging technique of the underwater surface of the structure and bed surface of the sea or a river using the side scan sonar in the future.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.268-272
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• 2007

현재 시행되고 있는 하천정비와 하도정비는 하천 흐름의 특성을 간과한 채 일괄적으로 진행되어 왔으며 그 결과로 하천의 인공화는 지금까지 계속되고 있다. 이에 따라 하천 및 하도의 물리, 화학, 생물에 미치는 영향은 심각하며, 그 동안 인위적인 하천교란의 요인과 하천교란에 따른 영향, 즉 하상변동, 외래종 식생 침입, 생태서식처 변화 등의 정량적 평가 기술의 수립은 매우 미흡한 상태이다. 뿐만 아니라 하천 교란 극복을 위한 저감기술, 복원기술 및 적응관리 기술 또한 체계적으로 정리되지 못하여 하천과 댐 관리당국이 어려움을 겪고 있다. 이러한 상황을 극복하기 위해서는 하천 교란에 대항하는 회복관리 기술 개발을 위한 교란 평가 기술이 필요하다. 따라서 본 연구에서는 항공사진 및 GIS기법을 이용하여 국내 주요하천의 원인별 교란실태를 조사하고 분석함으로써 하천교란 조사기술 개발에 응용할 수 있는 방안을 제시하고자 하였다. 분석을 위하여 댐 하류의 하천교란 및 적응현장 시범지역을 선정한 후 대상 지역의 항공사진을 GIS화하여 하천 교란 실태를 분석하는 데에 필요한 자료를 생성하였으며 생성된 자료를 바탕으로 하천의 평면 및 단면의 변화특성을 조사할 수 있었다. 또한 경년별 저수로 형태와 하천 중심선 비교 분석을 통하여 저수로의 이동 및 변화 양상을 규명해 낼 수 있었으며 그 결과 댐 하류지역에서 하도안정문제가 발생하였음을 확인할 수 있었다. 본 연구 결과를 바탕으로 보다 효율적인 하도안정문제에 관한 대책수립이 가능하리라 보며, 이를 위해서는 하천 교란 조사기술 개발에 대한 연구가 뒤따라야 할 것이다.과적임을 알 수 있었다. 실험 결과 본 기법으로 유휴시간에 프로세서를 저전력모드로 바꾸는 기존의 고전적인 전력 관리 기법보다 전체 시스템 전력 소모를 9% 더 절약할 수 있었다. 위성영상과 DEM 개발기술이 87% 이상의 점수를 받아 가장 시장성 및 활용성이 높은 기술로 평가되었으며, 초다분광영상에 대한 기술은 70%를 겨우 넘는 수준에서 평가가 되었다. 멀티센서 공간영상정보 통합처리 기술 개발은 다목적 실용위성의 보유, 국가 NGIS 사업의 결과물이 상당히 축척이 되어 있고, 라이다(LiDAR) 기술의 도입을 위한 환경이 조성되었기에 다른 국가에 비해 멀티센서 기술의 적용과 산업화가 가시화 될 수 있을 것으로 기대된다. 그러나 멀티센서 자료의 수급이 용이하지 못하고, 법 제도적인 한계, 시장의 성숙도가 기대이하라는 점 등의 한계를 노정하고 있다.a var. sieboldii 3. Pinus densiflora, Q. aliena, Q. acutissima, P. thunbergii, Q. acuta 4. Carpinus laxiflora, Camellia japonicas. C. tschonoskii community의 5개 그룹으로 나타났다. 하류의 부착돌말류는 상대적으로 양호한 수질을 가지고 있는 정점 1에서 다양한 생물상을, 탄천의 영향을 받는 정점 2는 상대적으로 수질이 악화되어 호오염성 종들이 높은 분포를 나타내고 있었다. 또한 부착돌말류 중 Cymbella minuta는 다른 부착돌말류에 비해 강한 오염지표성을 나타내고 있었다.p=0.000, $4.76{\pm}3.31$