• Bulletin of the Korean Chemical Society
• /
• 제26권1호
• /
• pp.178-180
• /
• 2005

• 한국보육학회지
• /
• 제18권4호
• /
• pp.199-211
• /
• 2018

본 연구는 유아의 수학적 능력 및 과학적 능력과 지능 간의 관계를 알아보고, 수학적 능력 및 과학적 능력의 지능에 대한 상대적 영향력을 알아보는데 목적이 있다. S시 S구에 위치한 유치원에 재원중인 만 5~6세 유아 100명을 연구대상으로 하였다. 유아의 수학적 능력 및 과학적 능력과 지능 간의 상관관계를 알아보기 위해 유아의 연령, 성별을 통제한 편상관분석을 실시하였고, 수학적 능력 및 과학적 능력의 지능에 대한 상대적 영향력을 알아보기 위해 단계적 중다회귀분석을 실시하였다. 수학적 능력과 과학적 능력은 지능과 관련이 있으며, 수학적 능력의 하위요인인 '측정', '대수'에서 과학적 능력의 하위요인인 '예측하기'에서 지능과 높은 상관이 나타났다. 수학적 능력과 과학적 능력의 지능에 대한 상대적 영향력은 수학적 능력이 더 많은 영향력을 미치는 것으로 나타났다. 이에 유아교육 기관 및 가정에서 수학과 과학 활동을 고르게 제공하고, 수학과 과학 통합 활동 제공 시 과정의 통합이 이루어질 수 있도록 고려해야 한다. 본 연구는 수학적 능력 및 과학적 능력과 지능 간의 관계를 찾고, 지능에 대한 상대적 영향력을 밝힘으로써 수학과 과학 통합 활동 계획 및 관련 프로그램 개발을 위한 기초자료로 활용하는데 의의가 있다고 할 수 있다.

• 대한원격탐사학회지
• /
• 제29권1호
• /
• pp.95-104
• /
• 2013

3-5 ${\mu}m$ 파장대의 중적외선 영상으로부터 정밀한 절대온도를 추정하기 위해서는 지표 복사율, 대기효과, 낮 영상의 경우 반사되는 태양빛에 대한 정보를 필요로 하며, 이는 온도 추정 시 오차를 발생시키는 주요 원인이 된다. 이 연구는 이를 해결하기 위해 상대적인 온도 차이를 추정하는 방법을 제안하고자 한다. 제안된 알고리즘의 기본 방향은 온도 추정을 위한 입력자료를 최소화 시키는 것이다. 이를 위해 인접한 지역에 위치한 두 대상물체가 받는 대기효과는 동일하다고 가정하였으며 MODTRAN 및 ASTER spectral library로부터 입력자료를 단순화 시키는 연구가 수행되었다. 시뮬레이션 연구 결과 제안된 상대온도추정알고리즘의 정밀도는 300 K의 온도에서 0.1의 지표 복사율 오차에 대해 2 K 이내의 비교적 높은 정밀도를 나타냈다. 그러나 낮 영상에서 저온인 경우에는 정밀도가 크게 감소하였다. 알고리즘의 검증을 위해 MODIS band 23 중적외선 낮 영상에 적용하였으며, 이를 MODIS LST 자료와 비교를 수행한 결과 $0.485{\pm}1.552$ K의 오차를 나타내었다. 이 결과로부터 제안된 알고리즘이 외부 입력자료를 필요로 하지 않고 단지 영상 만으로부터 비교적 높은 정밀도로 온도 추정이 가능함을 보였다. 그러나 제안된 알고리즘은 상대온도만을 알 수 있으며, 절대온도를 추정하기 위해서는 기준온도에 대한 정보가 필요하다는 한계점도 있다.

• Wind and Structures
• /
• 제11권1호
• /
• pp.35-50
• /
• 2008

Wind and temperature have been shown to be the critical sources causing changes in the modal properties of large-scale bridges. While the individual effects of wind and temperature on modal variability have been widely studied, the investigation about the effects of multiple environmental factors on structural modal properties was scarcely reported. This paper addresses the modeling of the simultaneous effects of wind and temperature on the modal frequencies of an instrumented cable-stayed bridge. Making use of the long-term monitoring data from anemometers, temperature sensors and accelerometers, a neural network model is formulated to correlate the modal frequency of each vibration mode with wind speed and temperature simultaneously. Research efforts have been made on enhancing the prediction capability of the neural network model through optimal selection of the number of hidden nodes and an analysis of relative strength of effect (RSE) for input reconstruction. The generalization performance of the formulated model is verified with a set of new testing data that have not been used in formulating the model. It is shown that using the significant components of wind speeds and temperatures rather than the whole measurement components as input to neural network can enhance the prediction capability. For the fundamental mode of the bridge investigated, wind and temperature together apply an overall negative action on the modal frequency, and the change in wind condition contributes less to the modal variability than the change in temperature.

• Animal Bioscience
• /
• 제34권7호
• /
• pp.1181-1192
• /
• 2021

Objective: The objective of the current study was to investigate the effects of dietary hatchery by-products (HBPs) as a replacement of fish meal (FM) on growth performance, relative organ weight, plasma measurements, immune organ index, meat quality, and tibia characteristics of broiler chickens. Methods: A total of 720 broiler chickens (3 d of age) were randomly allotted to 1 of 9 treatments with 8 replicates. Each replicate consisted of 5 male and 5 female birds. The basal diet was formulated to contain 5.0% commercial FM, whereas eight treatment diets were prepared by replacing 25%, 50%, 75%, or 100% of FM in the basal diet with infertile eggs (IFE) or a mixture of various HBPs (MIX); therefore, the inclusion levels of IFE or MIX in the experimental diets were 1.25%, 2.50%, 3.75%, or 5.00%. The diets and water were provided on an ad libitum basis for 32 d. Results: Increasing inclusion levels of IFE as a replacement of FM in diets had no effects on growth performance, plasma measurements, immune organ index, and tibia characteristics of broiler chickens. Increasing inclusion levels of IFE in diets increased (linear, p<0.05) meat lightness (L^*) but decreased (linear, p<0.05) meat redness (a^*). The breast meat pH at 1-h postmortem was increased (linear, p<0.05) by increasing inclusion levels of IFE in diets. Likewise, increasing inclusion levels of MIX in diets had no effects on growth performance, relative organ weight, plasma measurements, immune organ index, and tibia characteristics. However, increasing inclusion levels of MIX in diets increased (linear, p<0.05) 1-h postmortem pH but decreased (linear, p<0.05) 24-h postmortem pH of breast meat. Increasing inclusion levels of MIX in diets decreased (linear, p<0.05) thiobarbituric acid reactive substances values of breast meat. Conclusion: Both IFE and MIX are suitable alternatives to FM as protein ingredients in broiler diets.

• 아동학회지
• /
• 제34권1호
• /
• pp.123-140
• /
• 2013

The purpose of this study was to examine the effects of counting ability on young children's mathematical ability and mathematical learning potential. The subjects in this study were 75 young children of 4 & 5 years old who attended kindergartens and child care center in the city of B. They were evaluated in terms of counting ability, mathematical ability and mathematical learning potential(training and transfer) and the correlation between sub-factors and their relative influence on the partipants' mathematical ability was then analyzed. The findings of the study were as follows : First, there was a close correlation between the sub-factors of counting and those of mathematical ability. As a result of checking the relative influence of the sub-factors of counting on mathematical ability, reverse counting was revealed to have the largest impact on total mathematical ability scores and each sub-factors including algebra, number and calculation, geometry and measurement. Second, the results revealed a strong correlation between counting ability and mathematical learning ability. Regarding the size of the relative influence of the sub-factors of counting ability on training scores, reverse counting was found to be most influential, followed by continuous counting. While in relation to transfer scores, reverse counting was found to exert the greatest influence.

• 한국초지조사료학회지
• /
• 제8권1호
• /
• pp.61-65
• /
• 1988

To examine the effects of light intensity on photosynthesis, corn and sorghum species were grown under shade cloths, which reduced light intensity by 25,50 and 75%. Photosynthetic rates were measured between 10 a.m. to noon on a clear day in early and mid - summer. 1. The degree of shading had a little effect on microenvironment. Air, soil and leaf temperatures were reduced as shade increased. 2. The degree of shading in early summer had relatively a little effect on photosynthesis of corn. However, the rates of photosynthesis in mid-summer decreased by 36%, 55% with relative light intensities of 50% and 25%, respectively. 3. The rate of photosynthesis was highly correlated with light intensity. The rates of photosynthesis with relative light intensities of 75,50 and 25% were decreased by 20, 40 and 5 4% in early summer, and by 17-53%, 36-64% and 5570% in mid-summer, respectively. 4. The 75% of light intensity had relatively little effect on dry matter yield of corn and sorghum species, however dry matter yield with 50 and 25% relative light intensities was decreased 17 and 36% in corn, 13-3 1 and 50-68% in sorghum species, respectively.

• 펄프종이기술
• /
• 제36권3호
• /
• pp.60-66
• /
• 2004

The effects of roll diameter, winding time, winding methods and relative humidity on curl In newsprints(46$g/m^2$, 54 $g/m^2$, and 54 $g/m^2$ SNC) are examined. The larger MD curl appears at smaller roll diameter, with the extension of winding time, and at the treat ment of soft nip calendering. The MD curl shows the back side curl at winding methods with top side as outer side(TSO), and the top side curl with top side as inner side(TSI). While the CD curl in newsprints( 46 $g/m^2$, and 54 $g/m^2$ SNC) treated with calender is hardly influenced by the storage times, roll diameter, and winding methods. However the CD curl in newsprint(54 $g/m^2$) gradually increases to a two weeks, and then hold constant regardless of roll diameter and winding methods.. The CD curl shows always the top side curl regardless of winding methods. At high relative humidity, the CD curl largely reduces, but the MD curl is not nearly changed. Especially, the CD curl in news-prints(54 $g/m^2$ SNC) is little affected by the changes of relative humidity.

• Earthquakes and Structures
• /
• 제17권6호
• /
• pp.533-543
• /
• 2019

This paper presents a study on the behavior of an RC bridge under near-field and far-field ground motions. For this purpose, a dynamic nonlinear finite element time history analysis has been conducted. The near-field and far-field records are chosen pairwise from the same events which are fits to the seismic design of the bridge. In order to perform an accurate seismic evaluation, the model has been analyzed under two vertical and horizontal components of ground motions. Parameters of relative displacement, residual displacement, and maximum plastic strain have been considered and compared in terms of near-field and far-field ground motions. In the following, in order to decrease the undesirable effects of near-field ground motions, a viscous damper is suggested and its effects have been studied. In this case, the results show that the near-field ground motions increase maximum relative and residual displacement respectively up to three and twice times. Significant seismic improvements were achieved by using viscous dampers on the bridge model. Somehow under the considered near-field ground motion, parameters of residual and relative displacement decrease dramatically even less than the model without damper under the far-field record of the same ground motion.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
• /
• pp.311-313
• /
• 1997

The effects of porosity on the pressureless sintered $\beta$-SiC-$ZrB_2$ composites with $Al_2O_3$ additions(4, 8, 12wt.%) under argon atmosphere were investigated. Relative density of $\beta$-SiC-$ZrB_2$ composites were decreased with the $Al_2O_3$ content. The relative density and fracture toughness of $\beta$-SiC-$ZrB_2$ with 4wt% $Al_2O_3$ are 93.2%, $1.323MPa{\cdot}m^{1/2}$ respectively. The Vicker's hardness and flexural strength of $\beta$-SiC-$ZrB_2$ with 12wt.% $Al_2O_3$ are 0.492GPa, 261MPa respectively. Fracture toughness of $\beta$-SiC-$ZrB_2$ composites are directly proportional to relative density.