• Title/Summary/Keyword: 한국 수학

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Perception of the Gifted Science Students' Mothers on Giftedness (과학영재를 둔 어머니들의 영재성에 대한 인식)

  • Chung, Duk-Ho;Park, Seon-Ok;Yoo, Hyo-Hyun;Park, Jeong-Ju
    • Journal of Gifted/Talented Education
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    • v.24 no.4
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    • pp.561-576
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    • 2014
  • The purpose of this study is to investigate the perception of the mothers of science gifted in respect to giftedness compared to the "Scale for Rating the Behavioral Characteristics of Superior Students-R(SRBCSS-R)". For that, a survey of 18 mothers of elementary school science gifted and 32 mothers of middle school science gifted was conducted in relation to giftedness. The words and frame of this survey were analyzed using the Semantic Network Analysis. The results are as follows : The mothers of Elementary school science gifted perception were found to have a connected giftedness with reading, science, making something, etc.. On the other hand, the mothers of middle school science gifted perception were found to have a connected giftedness with problem, solving problem, mathematics, etc. in words analysis. The mothers of Elementary school science gifted have a strong connection with category on creativity, motivation, etc.. On the other hand, the mothers of middle school science gifted were more inclined towards the category on learning, motivation, etc. in frame analysis. That is to say, the mothers of science gifted are perceptive about giftedness respect to some elements as the "Scale for Rating the Behavioral Characteristics of Superior Students-R" on the giftedness. Therefore, a correct understanding about giftedness in respect to the mothers of science gifted is required and parent education is needed for appropriate science gifted education.

A PRELIMINARY STUDY OF CHILDREN WITH LEARNING DISORDER IN KOREA (한국에서의 학습장애 아동에 대한 예비적 연구 - 종합병원 학습장애 특수 클리닉 내원 아동을 중심으로 -)

  • Kim, Seung-Tai;Kim, Ji-Hae;Hong, Sung-Do;Joung, Yoo-Sook
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.7 no.2
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    • pp.247-257
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    • 1996
  • This is a preliminary report on the first segment of a continuing and prospective teaming disorder study project in Korea. Study subjects were 197 children, aged between 6 and 15 referred for psychiatric evaluation of scholastic problems. Demographic data, psychiatric diagnoses and intelligence and achievement test results were reviewed and analyzed. Analyses of data lead to the following conclusions : (1) About 20.8% of children referred for scholastic problems were diagnosed of teaming disorder(LD). The most prevalent diagnosis among these children with scholastic problem was emotional disorder, especially depressive disorder(33%), (2) The comorbid rate of attention deficit/hyperactivity disorder(ADHD) of 41 children with LD was 44%, (3) Male/female ratio was 5.8:1 among all of the LD children, 17:1 among children with LD and ADHD and 3.6:l among children with LD but without ADHD, (4) 83% of children with LD scored above middle level on socioeconomic status(SES), (5) Age, SES, IQ, family psychiatric history, past history of medical and psychiatric illness, onset of age, pattern of peer relationship, number of friends, presence of adaptation problem and academic achievements of children with LD and ADHD compared to those of children with LD but without ADHD. No significant differences between two groups were found on age, SES, IQ, family psychiatric history, past history of medical and psychiatric illness, pattern of peer relationship, number of friends and presence of adaptation problem. However, there were significant differences in academic achievements of Korean language total, speaking and listening score, arithmetic score, social science score and music score of children with LD and ADHD compared to those of children with LD but without ADHD. Also there was an ealier onset of age in LD and ADHD group when compared to LD but without ADHD group.

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Dynamic-size Multi-hop Clustering Mechanism based on the Distance in Sensor Networks (센서 네트워크에서의 거리에 따른 동적 크기 다중홉 클러스터링 방법)

  • Ahn, Sang-Hyun;Lim, Yu-Jin
    • The KIPS Transactions:PartC
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    • v.14C no.6
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    • pp.519-524
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    • 2007
  • One of the most important issues on the sensor network with resource limited sensor nodes is prolonging the network lifetime by effectively utilizing the limited node energy. The most representative mechanism to achieve a long lived sensor network is the clustering mechanism which can be further classified into the single hop mode and the multi hop mode. The single hop mode requires that all sensor nodes in a cluster communicate directly with the cluster head(CH) via single hop md, in the multi hop mode, sensor nodes communicate with the CH with the help of other Intermediate nodes. One of the most critical factors that impact on the performance of the existing multi hop clustering mechanism is the cluster size and, without the assumption on the uniform node distribution, finding out the best cluster size is intractable. Since sensor nodes in a real sensor network are distributed non uniformly, the fixed size mechanism may not work best for real sensor networks. Therefore, in this paper, we propose a new dynamic size multi hop clustering mechanism in which the cluster size is determined according to the distance from the sink to relieve the traffic passing through the CHs near the sink. We show that our proposed scheme outperforms the existing fixed size clustering mechanisms by carrying out numerical analysis and simulations.

Mortality Forecasting for Population Projection (장래인구추계를 위한 사망률 예측)

  • Kim, Tai-Hun
    • Korea journal of population studies
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    • v.29 no.2
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    • pp.27-51
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    • 2006
  • In this paper, I have tested various kinds of methods for mortality projection and chose Lee-Carter method for projection of Korean mortality by age and sex. I reviewed the trends of life tables and life expectancies by age and sex from 2005 to 2050 projected by Lee-Carter method and found that the method was very applicable for Korean mortality projection. The differences between reported and estimated data for the period of 1971-2003 were small enough for both sexes and for all of the age groups. The projected life expectancies in 2051 were 82.73 years for males and 89.41 for females, and the differences decreased from 7.06 years in 2005 to 6.68 years. Because of the limitation of Korean infant mortality rate, I adopted the Japanese estimated IMR in 2050 as Korean object level in 2051. When the time series of IMR become long enough, we can use Korean IMR directly for the mortality projection. In addition, if we can estimate the changes of the main cause of death correctly in future, the mortality projection will be more correct and reliable. This will be available when we can produce a long series of life tables by cause of deaths.

Comparison of the Regulatory Models Assessing Off-Site Radiological Dose due to the Routine Releases of Tritium (삼중수소의 환경방출에 따른 주민선량 규제모델의 비교)

  • Hwang Won-Tae;Kim Eun-Han;Han Moon-Hee;Choi Yong-Ho;Lee Han-Soo;Lee Chang-Woo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.3 no.2
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    • pp.125-133
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    • 2005
  • Methodologies of NEWTRIT model, NRC model and AIRDOS-EPA model, which are off-site dose assessment models for regulatory compliance from routine releases of tritium into the environment, were investigated. Using the domestic data, if available, the predictive results of the models were compared. Among them, recently developed NEWTRIT model considers only doses from organically bounded tritium (OBT) due to environmental releases of tritiated water (HTO) . A total dose from all exposure pathways predicted from AIRDOS-EPA model was 1.03 and 2.46 times higher than that from NEWTRIT model and NRC model, respectively. From above result, readers should not have an understanding that a predictive dose from NRC model may be underestimated compared with a realistic dose. It is because of that both mathematical models and corresponding parameter values for regulatory compliance are based on the conservative assumptions. For a dose by food consumption predicted from NEWTRIT model, the contribution of OBT was nearly equivalent to that of HTO due to relatively high consumption of grains in Korean. Although a total dose predicted from NEWTRIT model is similar to that from AIRDOS-EPA model, NEIIfTRIT model may be have a meaning in the understanding of phenomena for the behavior of HTO released into the environment.

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Simplified Approximation Method of the Multi-Compartments Model on the Migration of Contaminant through Unsaturated Zone (불포화대에서 오염물질 이동현상에 대한 다중구획 모델의 단순 근사방법)

  • Cheong, Jae-Hak
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.29-37
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    • 2007
  • A conventional single compartment model cannot simulate reasonably the migration phenomenon of contaminants through unsaturated zone, due to the intrinsic unrealistic assumption of the compartment model that contaminants entering a compartment are immediately and uniformly mixed. Although, a multi-compartments model, in which even physically identical layer is divided into multiple compartments, may be used for explaining the retardation of contaminant mass flux along with increasing number of compartments, its numerical modeling is usually time-consuming and appropriate analytical solutions have not been reported yet. In order to improve the conventional compartment models on contaminant migration through unsaturated zone, a series of analytical solutions for multi-compartments model were derived and a generalized constraint under which the results from multi-compartments model can be simply approximated by single compartment model was proposed. The simplified approximation method was verified by a simple numerical analysis on the constraint under hypothetical conditions. It was also proved that the influent contaminant transfer rate from the bulk unsaturated zone can be generally represented into a time-dependent nominal transfer rate rather than a constant. In addition, the nominal transfer rate turned out to be very sensitive to the contaminant transfer rate between compartments in unsaturated zone, but to be almost insensitive to the transfer rate from contaminated zone. It is expected that the simplified approximation method developed in this study can be used for rapid and reasonable estimation of the migration phenomenon of contaminant through unsaturated zone, instead of time-consuming multi-compartments modeling.

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A Study on Ventilation System of Underground Low-Intermediate Radioactive Waste Repository (지하 동굴식 중-저준위 방사성 폐기물 처분장의 환기시스템 고찰)

  • Kim, Young-Min;Kwon, O-Sang;Yoon, Chan-Hoon;Kwon, Sang-Ki;Kim, Jin
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.65-78
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    • 2007
  • The pollutants (Rn, CH, CO, HS, radioactive gas from radiolysis) were generated from the process of construction and operation of underground repository, and after disposal of low-intermediate radioactive waste inside there must be controlled by a ventilation system to distribute them in area where enough air is supported. Therefore, a suitable technical approach is needed especially at an underground repository that is equipped with many entry tunnels, storage tunnels, exhaust-blowing tunnels, and vertical shafts in complicated network form. For the technical approach of such a ventilation system, WIPP (Waste Isolation Pilot Plant) in U. S and SFR (Slutforvar for Reaktorafall) low-intermediate radioactive waste repository in Sweden were selected as the models, for calculating the required air quantity, organizing a ventilation network considering cross section, length, surface roughness of the air passage, and describing a calculation of resistance of each circuit. Based on these procedures, a best suited ventilation system was completed with designing proper capacity of fans and operating plan of vertical shafts. As a result of comparing the two repositories based on the geometry dimensions and ventilation facility equipment operation, more parallel circuit as in WIPP, brought decrease in resistance for entire system leading to reduce of operating costs, and the larger cross-sectional area of the SFR, the greater the percentage of disposal capacity. Accordingly, the mixture of parallel circuit of WIPP repository for reducing resistance and SFR repository formation for enlargement of disposal capacity would be the most rational and efficient ventilation system.

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Analysis of the Behavior of Tubular-Type Equipment for Nuclear Waste Treatment : Sensitivities of the Parameters Affecting Mass Transfer Yield (방사성폐기물의 화학처리공정에 사용되는 유동관식 장치의 해석 : 물질전달 수율에 미치는 매개변수들의 민감도)

  • Yoo, Jae-Hyung;Lee, Byung-Jik;Shim, Joon-Bo;Kim, Eung-Ho
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.5 no.1
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    • pp.91-99
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    • 2007
  • It was intended in this study to investigate the effects of various parameters on the chemical reaction or mass transfer yield in a tubular-type nuclear waste treatment equipment. Since such equipments, as a tubular reactor, multistage solvent extractor, and adsorption column, accompany chemical reaction or mass transfer along the fluid-flowing direction, mathematical modeling for each equipment was carried out first. Then their behaviors of the chemical reaction or mass transfer were predicted through computer simulations. The inherent major parameters for each equipment were chosen and their sensitivities. affecting the reaction or mass transfer yield were analyzed. For the tubular reactor, the effects of axial diffusion coefficient and reaction rate constant on the reaction yield were investigated. As for the multistage solvent extractor, the backmixing of continuous phase and the distribution coefficient between fluid and solvent were considered as the major parameters affecting the extraction yield as well as concentration profiles throughout the axial direction of the extractor. For the adsorption column, the equilibrium constant between fluid and adsorbent surface, and the overall mass transfer coefficient between the two phases were taken as the major factors that affect the adsorption rate.

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Research on Geometric Shape in the 20th Century Design Education - Focused on the relation of $Fr{\ddot{o}}bel$ Kindergarten Education - (20세기 디자인교육의 기하학적인 형태에 대한 탐구 - 프뢰벨 유치원 교육과의 연관성을 중심으로 -)

  • Bang, Kyung-Rhan
    • Archives of design research
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    • v.18 no.2 s.60
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    • pp.325-334
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    • 2005
  • The purpose of this thesis is to explore the fundamental reasons and general circumstances of the introduction of geometric shape to the 20th century's design education. The modern design education was directly influenced by the German Kindergarten Movement and its educational ideal, so they began to employ geometric shapes in visual education. When Friedrich Frobel, a professional German child educator of the 19th century, invented the 'Spielgaben,' it soon became a popular educational tool. It was a turning point in the child educational system, from then they began to actively employ 'tools' in art education. The Spielgaben was created based on the geometric principle of a popular block game of the 19th century. On the other hand, a game program called 'Bechaftigungsmaterial' led early Modernists to adopt geometric shape in their works. Then, geometric shape were applied to a primary educational program designed by the Bauhaus that gave birth to the Modern design education in the 20th century. likewise, the substantial reasons why the principles of point/line/plain and geometric shapes had been taken in the 20th century design education can be explained through this historical background. This research is to investigate how Kindergarten Movement and Modern design education can be associated with each other, particularly in the light of geometric elements. Therefore, I first referred to the historic records in order to reveal their relation, and then analyzed the similarities and differences between the two activities. In result, I could explore the relationship between child educational tools and the 20th century's design education.

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Modeling of the dynamic behavior of a 12-V automotive lead-acid battery (12V 차량용 납축전지의 동적 거동 모델링)

  • Kim, Sung Tae;Lee, Jeong Bin;Kim, Ui Seong;Shin, Chee Burm
    • Journal of Energy Engineering
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    • v.22 no.2
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    • pp.175-183
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    • 2013
  • For the optimal design of the vehicle electric system, it is important to have a reliable modeling tool to predict the dynamic behavior of the automotive battery. In this work, a one-dimensional modeling was carried-out to predict the dynamic behaviors of a 12-V automotive lead-acid battery. The model accounted for electrochemical kinetics and ionic mass transfer in a battery cell. In order to validate the modeling, modeling results were compared with the experiment data of the dynamic behaviors of the lead-acid batteries of two different capacities that were mounted on the automobiles manufactured by Hyundai Motor Company. The discharge behaviors were measured with various discharge rates of C/3, C/5, C/10, C/20 and combination. And dynamic behaviors of charge and discharge were measured. The voltage curves from the experiment and simulation were in good agreement. Based on the modeling, the distributions of the electrical potentials of the solid and solution phases, and the current density within the electrodes could be predicted as a function of charge and discharge time.