• 컴퓨터교육학회논문지
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• 제4권1호
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• pp.127-134
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• 2001

공업계 고등학교 전기이론 교과 중에서 교류전기에 관한 단원은 수학과 물리에 대한 기본적인 이해를 바탕으로 하며 눈에 보이지 않는 다양한 현상들에 대한 개념적인 이해가 요구되는 부분이다. 반면 이를 학습하는 공업계 고등학교 학생들은 교류회로를 이해하는데 필요한 충분한 기초학력을 보유하고 있지 못할 뿐만 아니라 교재 또한 지나치게 이론중심으로 기술되어 있어 대부분의 학생들이 교류회로를 어렵게 느끼도록 하는 원인이 되고 있다. 본 연구에서는 교류회로를 이론보다는 원인-결과를 중심으로 설명하고 CAI 교재를 개발하여 교류신호의 기본 성질을 직접 보고 또 가상 실습을 통해 학생들이 보다 쉽게 개념을 파악할 수 있도록 하였다.

• Human Ecology Research
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• 제58권1호
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• pp.105-120
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• 2020

This study helps infant teachers practice a constructivism-based teacher education program that supports infant mathematical inquiry activities and examines improvements in mathematical teaching knowledge, mathematical teaching initiatives, mathematical interaction, constructivism belief and mathematical teaching efficacy. Twenty two experiment group infant teachers and twenty two comparison group infant teachers were chosen at two workforce educare centers. The experiment group infant teachers participated in 18 sessions of a constructivism teacher training program for 8 weeks, but the comparison group infant teachers did not take part in the program. Pretest and post-tests were implemented for the mathematical teaching knowledge, mathematical teaching initiatives, mathematical interactions, constructivism belief and mathematical teaching efficacy in the experiment group. Independent sample t-test and ANCOVA were tested using Windows SPSS statistics 21.0. The homogeneity test for the experiment and comparison group revealed significant differences. ANCOVA was carried out after the pretest score was controlled as a co-variance. Significant differences were indicated in mathematical teaching knowledge, mathematical teaching initiative, mathematical interaction, constructivism belief and mathematical teaching efficacy. The results indicated that a constructivism-based teacher education program to support infant mathematical inquiry activities influenced improvements in mathematical teaching knowledge, mathematical teaching initiative, mathematical interaction, constructivism belief and mathematical teaching efficacy. This study proved the effects of the program based on constructivism theory content for the knowledge, skills and attitude about infant teaching of mathematical initiatives and practiced a program of exploration, investigation, application and assessment for infant teachers. The results can help infant teachers teach mathematical exploration activities and help activate infant mathematical exploration activities.

• Computers and Concrete
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• 제20권5호
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• pp.605-616
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• 2017

Concrete filled steel tubular (CFST) composite girder is a new type of structures for bridge constructions. The existing design codes cannot be used to predict the thermal stress in the CFST truss girder structures under solar radiation. This study is to develop the temperature gradient curves for predicting thermal stress of the structure based on field and laboratory monitoring data. An in-field testing had been carried out on Ganhaizi Bridge for over two months. Thermal couples were installed at the cross section of the CFST truss girder and the continuous data was collected every 30 minutes. A typical temperature gradient mode was then extracted by comparing temperature distributions at different times. To further verify the temperature gradient mode and investigate the evolution of temperature fields, an outdoor experiment was conducted on a 1:8 scale bridge model, which was installed with both thermal couples and strain gauges. The main factors including solar radiation and ambient temperature on the different positions were studied. Laboratory results were consistent with that from the in-field data and temperature gradient curves were obtained from the in-field and laboratory data. The relationship between the strain difference at top and bottom surfaces of the concrete deck and its corresponding temperature change was also obtained and a method based on curve fitting was proposed to predict the thermal strain under elevated temperature. The thermal stress model for CFST composite girder was derived. By the proposed model, the thermal stress was obtained from the temperature gradient curves. The results using the proposed model were agreed well with that by finite element modelling.

• Asian-Australasian Journal of Animal Sciences
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• 제28권4호
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• pp.511-518
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• 2015

Calliandra calothyrsus preserved in silage is an alternative method for improving the crude protein content of feeds for sustainable ruminant production. The aim of this research was to evaluate the quality of silage which contained different levels of C. calothyrsus by examining the fermentation characteristics and microbial diversity. Silage was made in a completely randomized design consisting of five treatments with three replications i.e.: R0, Pennisetum purpureum 100%; R1, P. purpureum 75%+C. calothyrsus 25%;, R2, P. purpureum 50%+C. calothyrsus 50%; R3, P. purpureum 25%+C. calothyrsus 75%; and R4, C. calothyrsus 100%. All silages were prepared using plastic jar silos (600 g) and incubated at room temperature for 30 days. Silages were analyzed for fermentation characteristics and microbial diversity. Increased levels of C. calothyrsus in silage had a significant effect (p<0.01) on the fermentation characteristics. The microbial diversity index decreased and activity was inhibited with increasing levels of C. calothyrsus. The microbial community indicated that there was a population of Lactobacillus plantarum, L. casei, L. brevis, Lactococcus lactis, Chryseobacterium sp., and uncultured bacteria. The result confirmed that silage with a combination of grass and C. calothyrsus had good fermentation characteristics and microbial communities were dominated by L. plantarum.

• 정보교육학회논문지
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• 제12권1호
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• pp.77-88
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• 2008

프로그래밍 교육은 학생들의 창의력, 문제해결력, 논리적 사고력 향상 등에 긍정적인 영향을 끼친다. 하지만, 프로그래밍을 하기 위해서는 기본 문법과 구조를 이해하고 프로그램을 사용하는 방법을 익히는데 너무 많은 노력을 요구하는 등 문제점을 갖고 있으며, 이로 인해 학습자에게 프로그래밍에 대한 부정적인 인식을 갖게 한다. 따라서 본 연구에서는 배우기 쉽고, 직관적이며, 학습자의 문제해결력 향상을 도모할 수 있는 교육용 프로그래밍 언어(EPL)인 '스크래치'를 CPS(Creative Problem Solving) 모형을 활용해 적용해봄으로써 중학교 남녀 학습자에게 있어 문제해결력 향상과 프로그래밍 교육에 대한 태도에 어떠한 영향을 미치는지 단일집단 사전사후 검사를 통해 검증하였다.

• 정보교육학회논문지
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• 제17권1호
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• pp.9-21
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• 2013

본 연구의 목적은 학습 부진아의 연산능력 향상을 위한 스마트 폰 기반 모바일 어플 시스템을 설계 및 구현하는 것이다. 본 시스템의 특징은, 첫째, 학습자의 수준에 맞는 개별화된 학습이 이루어지는 스마트폰기반 시스템이다. 둘째, 학습자들의 동기를 지속시키기 위하여 즉각적인 피드백이 제공된다. 셋째, 연산능력은 꾸준한 연습을 통하여 향상시킬 수 있다는 것에 중점을 둔 지속적이고 반복적인 학습이 가능한 시스템이다. 구현된 본 교육시스템을 초등학교 6학년 수학 학습 부진아에게 적용시킨 결과는 다음과 같다. 첫째, 본 시스템을 활용하여 연산학습을 하는 것에 흥미를 느꼈으며 학습에 대한 내재적 동기가 유발되었다. 둘째, 연산속도가 빨라지고 연산의 정확도가 높아지는 등 학습자의 연산능력이 향상되었다.

• 대한수학회보
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• 제57권1호
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• pp.167-177
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• 2020

Let I be an ideal of Noetherian local ring (R, m) and M an artinian R-module. In this paper, we study colocalization of local homology modules. In fact we give Colocal-global Principle for the artinianness and minimaxness of local homology modules, which is a dual case of Local-global Principle for the finiteness of local cohomology modules. We define the representation dimension r^I (M) of M and the artinianness dimension a^I (M) of M relative to I by r^I (M) = inf{i ∈ ℕ₀ : H^I_i (M) is not representable}, and a^I (M) = inf{i ∈ ℕ₀ : H^I_i (M) is not artinian} and we will prove that i) a^I (M) = r^I (M) = inf{r^IR_𝖕 (_𝖕M) : 𝖕 ∈ Spec(R)} ≥ inf{a^IR_𝖕 (_𝖕M) : 𝖕 ∈ Spec(R)}, ii) inf{i ∈ ℕ₀ : H^I_i (M) is not minimax} = inf{r^IR_𝖕 (_𝖕M) : 𝖕 ∈ Spec(R) ∖ {𝔪}}. Also, we define the upper representation dimension R^I (M) of M relative to I by R^I (M) = sup{i ∈ ℕ₀ : H^I_i (M) is not representable}, and we will show that i) sup{i ∈ ℕ₀ : H^I_i (M) ≠ 0} = sup{i ∈ ℕ₀ : H^I_i (M) is not artinian} = sup{R^IR_𝖕 (_𝖕M) : 𝖕 ∈ Spec(R)}, ii) sup{i ∈ ℕ₀ : H^I_i (M) is not finitely generated} = sup{i ∈ ℕ₀ : H^I_i (M) is not minimax} = sup{R^IR_𝖕 (_𝖕M) : 𝖕 ∈ Spec(R) ∖ {𝔪}}.

• 대기
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• 제25권4호
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• pp.669-683
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• 2015

In this study, we investigated the prediction skills of four multiple linear regression methods for monthly air temperature over South Korea. We used simulation results from four regional climate models (RegCM4, SNURCM, WRF, and YSURSM) driven by two boundary conditions (NCEP/DOE Reanalysis 2 and ERA-Interim). We selected 15 years (1989~2003) as the training period and the last 5 years (2004~2008) as validation period. The four regression methods used in this study are as follows: 1) Homogeneous Multiple linear Regression (HMR), 2) Homogeneous Multiple linear Regression constraining the regression coefficients to be nonnegative (HMR+), 3) non-homogeneous multiple linear regression (EMOS; Ensemble Model Output Statistics), 4) EMOS with positive coefficients (EMOS+). It is same method as the third method except for constraining the coefficients to be nonnegative. The four regression methods showed similar prediction skills for the monthly air temperature over South Korea. However, the prediction skills of regression methods which don't constrain regression coefficients to be nonnegative are clearly impacted by the existence of outliers. Among the four multiple linear regression methods, HMR+ and EMOS+ methods showed the best skill during the validation period. HMR+ and EMOS+ methods showed a very similar performance in terms of the MAE and RMSE. Therefore, we recommend the HMR+ as the best method because of ease of development and applications.

• 한국수산과학회지
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• 제51권1호
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• pp.79-90
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• 2018

Fish ages are critical information in fish stock assessments because they are required for age-structure models such as virtual population analysis and stochastic catch-at-age models, whose outputs include recruitment strengths, a spawning stock size (abundance or biomass), and the projection of a fish population size in future. However, most countries other than the developed countries have not identified ages of fish caught by fisheries or surveys in a consistent manner for a long time (e.g.,>20 years). Instead, data about fish body sizes (e.g., lengths) have been well available because of ease of measurement. To infer age compositions of fish in a target group using fish length data, we intended to improve the length frequency analysis (LFA), which Schnute and Fournier had introduced in 1980. Our study was different in two ways from the Schnute and Fournier's method. First we calculated not only point estimates of age compositions but also the uncertainty in those estimates. Second, we modified LFA based on the von Bertalanffy growth model (vB-based model) to allow both individual-to-individual and cohort-to-cohort variability in estimates of parameters in the vB-based model. For illustration, we used data about lengths of Korean mackerel Scomber japonicas caught by purse-seine fisheries from 2000-2016.

• 영재교육연구
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• 제18권1호
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• pp.111-137
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• 2008

본 연구는 중학교 영재학급에서 활용할 수 있는 영재교육 자료를 개발하고 이의 적용을 통해 창의성 신장 효과를 알아보고자 하였다. 연구 대상은 충남교육청 지정 보령영재교육원 영재학급 학생 129명이다. 영재학급 학생들은 7학년과 8학년 학생으로 논리사고 분야, 과학분야, 수리분야, 외국어 분야로 구분하여 교육하였다. 영재교육 자료는 프로젝트 수행 활동을 기반으로 하고 있다. 프로젝트 수행 활동 수업은 영재들의 창의성 향상에 효과적인 것으로 나타났으며, 특히 과학분야의 경우 정교성, 유창성, 독창성 등에서 매우 효과적인 것을 알 수 있었다. 프로그램에 대한 설문조사에서는 영재들과 교사들 모두 체험중심의 프로젝트 수행 활동 수업에 대해 큰 만족감과 흥미를 나타내고 있었다. 결론적으로 본 연구에서 활용한 프로젝트 기반의 수행 중심의 프로그램은 영재교육에 적극 활용할 필요가 있음을 시사한다고 할 것이다.