• Journal of Educational Research in Mathematics
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• v.15 no.3
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• pp.315-334
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• 2005

The purpose of this study is to find out the implications on when and how the correlation concept can be taught. we investigate the development time and method of the concept in a statistical perspective those initially have discussed in psychology by Piaget. We first reviewed the 1958 research by Inhelder and Piaget. It was the first one which researched the development of the correlation and has become the foundation of psychological perspective. According to them, the correlation concept needs proportional and probability concept ahead of its development and argued on the coefficient of correlation based on formal and logical position. However, from a statistical perspective, the correlation concept is a part of the distribution concept. So, the level of the correlation concept grows from the comparison of conditional distributions to the conditional probability distribution where the proportional concept and probability concept are applied. As reviewed through the literature, we found that 11-12 years old students in early formal operation stage reasoned about correlation through the comparison of conditional distributions. In our study, we argue that we need to consider the possibility of beginning didactic mediation for correlation concept earlier and the method approaching it in a distribution perspective.

• Korean Journal of Childcare and Education
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• v.9 no.5
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• pp.131-156
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• 2013

The purpose of this study was to examine the importance of parental beliefs, parental attitudes and parental behaviors of parents with preschool children and the relationship of the variables in an attempt to help preschoolers to gain multiple-intelligence experiences in an integrated manner in consideration of their interests, needs, strengths and weaknesses. A survey was conducted on the selected parents who had preschool children, and a multiple regression analysis was carried out to look for connections among the variables. The findings of the study were as follows: First, the preschool girls were ahead of the preschool boys in linguistic intelligence, musical intelligence and spatial intelligence, and the latter surpassed the former in logical-mathematical intelligence. Second, whether there would be any differences among the preschoolers in multiple intelligences according to age was analyzed, and those who were at the Western age of five were ahead of the four-year-olds in logical-mathematical intelligence, bodily-kinesthetic intelligence and naturalist intelligence. Third, the parental attitude of the parents was identified as the most influential variable for the multiple intelligences of the preschoolers, followed by parental behavior. Parental beliefs just had a very small impact on their multiple intelligences. The findings of the study imply that parents should be helped to improve their parental attitude and parental behavior to boost the multiple intelligences of their preschool children.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.348-351
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• 2003

산소 과전압이 낮은 $MnO_2$를 촉매로 사용하여 반도체 산화물계의 산소선택성 전극을 제조하고 산화물 coating층의 미세구조와 전기화학적 특성을 분석하였다. Ti 기판에 열분해 법을 이용하여 $MnO_2$ 피막을 형성하였고, 또한 PVDF : $MnO_2$의 함량비를 1 : 1에서 1 : 40까지 정량적으로 변화시키고 DMF의 함량을 각각의 고정된 PVDF : $MnO_2$의 함량비에서 변화시켜 Pb전극에 1.5 mm/sec의 속도로 5회 dipping하여 $MnO_2$ 피막층을 형성 하였다. $450^{\circ}C$에서 1시간 열분해하여 약 $1\;{\mu}m$의 $MnO_2$ 피막층이 형성되었으나 Ti 기판과의 접착력이 약하여 피막자체에 대한 전기화학적 특성을 관찰할 수 없었다. PVDF : DMF = 4 : 96인 경우 pb 전극의 피막층이 얇기 때문에 박리현상이 일어났으며 이는 산화물 용제의 낮은 점도 때문인 것으로 판단된다. 또한 PVDF : DMF = 10 : 90의 경우는 5회 dipping 하여 약 $150\;{\mu}m$의 피막층을 형성하였다. PVDF : $MnO_2$의 함량비가 1:1에서 1:6 까지는 DMF의 함량에 무관하게 전극 특성이 나타나지 않았지만 $MnO_2$의 양이 상대적으로 증가하면 cycle이 증가하더라도 거의 일정한 전류 값을 갖고 $MnO_2$와 PVDF의 비가 20:1 이상의 조성에서는 균일한 CV 특성을 나타냈다. 이는 $MnO_2$가 효과적으로 촉매 작용을 한 것으로 판단되며 anodic polarization에 의한 산소 발생 과전압도 약 1.4V 정도로 감소되었다.동등한 MSIL 코드를 생성하도록 시스템을 컴파일러 기법을 이용하여 모듈별로 구성하였다.적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기법에 의해서 개선되었다. 답이 없는 문제, 문제 만들기, 일반화가 가능한 문제 등으로 보고, 수학적 창의성 중 특히 확산적 사고에 초점을 맞추어 개방형 문제가 확산적 사고의 요소인 유창성, 독창성, 유연성 등에 각각 어떤 영향을 미치는지 20주의 프로그램을 개발, 진행하여 그 효과를 검증하고자

• Journal of the Korean Arthroscopy Society
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• v.8 no.1
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• pp.14-18
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• 2004

Purpose: To compare the mid-term follow-up results of anterior cruciate ligament(ACL) reconstruction with the bone-patellar tendon- bone(BTB) autograft to those with the BTB allograft. Materials and Methods: Retrospective study was performed in 59 cases with BTB autograft and 42 cases with BTB allograft. Evaluations include Lysholm score, 2000 IKDC subjective knee score, Shelbourne patello-femoral pain score , Lachman test, pivot shift test, KT-1000 arthrometer test and 2000 IKDC knee examination. Results: There were no significant statistic differences between two groups in Lysholm score and 2000 IKDC subjective knee score of more than 70 (p<0.05). Five cases(8.5%) showed the patello-femoral pain score less than 80 according to Shelboume with autograft group and two cases(4.8%) with allograft group (p<0.05). Lachman test, pivot shift test and KT-1000 arthrometer test showed no significant statistic differences between two groups(P<0.05). Fifty-four cases(91.5%) were normal or nearly normal according to the 2000 IKDC knee examination with autograft group and thirty-eight cases(90.4%) with allograft group(p<0.05).Conclusion: BTB allograft as well as BTB autograft is considered to be an acceptable choice for ACL reconstruction.

• Journal of the Korean Society of Marine Environment & Safety
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• v.17 no.4
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• pp.383-389
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• 2011

At the design stage, it is very important to know the ship maneuvering characteristics from the view point of ship performance and for the safety of navigation. IMO only gives some criteria for ships in full load even keel condition. However, the ship generally is operated not only in full load condition but also in half load condition or ballast condition. Therefore we must estimate the ship maneuvering in different loading condition to ensure that the ship will satisfy with IMO rules and navigate safely in every condition. In this paper, we have investigated the maneuvering characteristics of a ship by simulation and experiments with real ship. By comparing with the results of simulation, the real ship tests conform with simulation test and previous researches. Therefore, the method base on real data is well done to estimate the ship maneuvering in different loading conditions. The change of ship's manoeuverability accoriding to ship's operation conditions was estimated.

• Journal of Internet Computing and Services
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• v.12 no.4
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• pp.1-14
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• 2011

This paper analyzes the fairness and efficiency of channel sharing when heterogeneous wireless networks that have different transmission power and/or coverage coexist with the contention-based channel access protocol. First, we show that the existing CSMA (carrier sensing multiple access) protocol, that is a prevailing contention-based mechanism, results in significant unfairness of channel access because of (1) the asymmetric capability of carrier sensing and (2) the blindness of binary exponential backoff and link adaptation mechanisms to the interference-driven transmission failures. Next, we derive the feasible region of carrier sensing thresholds that assures spatial reuse and fair channel sharing simultaneously. Moreover, we establish an analytical model for per-system throughput and investigate the effect of contention window size and transmission rate on the fairness and efficiency of channel sharing. Finally, we compare the performance of several approaches for fair channel sharing via simulations under various network configurations.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.596-603
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• 2020

In this study, a mathematical model for optimal operation of the fusion fuel cycle is developed based on scheduling approach. The fusion fuel cycle consists of a system for storing and supplying deuterium and tritium, and receiving and separating process after the fusion reaction. Except that tritium is a radioactive material, most of these processes consist of catalytic reactions and separation process. For these reasons, it is possible to apply scheduling approach which is also widely utilized to chemical plants to derive the optimal operating scenarios. The developed model determined the optimal regeneration cycle to minimize the amount of tritium inside the vacuum pumps. Based on the characteristics of various device in the fusion reactor, the optimal tritium plant operation scenario is evaluated. The formulated model was applied to the actual tokamak scenario and utilized to analyze the fuel flow and balance of ITER fuel cycle.

• KIPS Transactions on Software and Data Engineering
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• v.3 no.1
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• pp.43-48
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• 2014

Usually, image deconvolution is applied as a preprocessing step in surveillance systems to reduce the effect of motion or out-of-focus blur problem. In this paper, we propose a blind-image deconvolution filtering approach based on genetic programming (GP). A numerical expression is developed using GP process for image restoration which optimally combines and exploits dependencies among features of the blurred image. In order to develop such function, first, a set of feature vectors is formed by considering a small neighborhood around each pixel. At second stage, the estimator is trained and developed through GP process that automatically selects and combines the useful feature information under a fitness criterion. The developed function is then applied to estimate the image pixel intensity of the degraded image. The performance of developed function is estimated using various degraded image sequences. Our comparative analysis highlights the effectiveness of the proposed filter.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.10a
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• pp.411-413
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• 2010

Now, smart phone markets are grows quickly. So it is needed research of CDN(Contents Delivery Network) technology for contents transmission in mobile networks. Especially the services of smart phone are focused on open platform model. So P2P(Peer to Peer) protocols will be used for mobile network because it is a distributed network architecture composed of participants that make a portion of their resources directly available to other network participants, without the need for a central server. Current research of P2P protocols for mobile network are not activated. The reason is appropriate in the mobile P2P network simulation environment, since it is not provided. So, in this paper we design a mobile P2P simulation system for CDN based on mobile P2P.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1485-1491
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• 2019

As the type and size of vital signs become extensive at the moment lately, a research is actively progressing to define vital signs as big data and analyze it. We generally use a similar method of processing big data on social network as a way to treat vital signs as big data. Vital Sign Big Data should be extracted as feature data, stored separately, and analyzed with various analytical instruments. In other words, it should ensure interoperability and compatability of data, and the index expression in analytical tools should be concise. For this end, I defined the vital sign as the standard meta-model base of HL7 in this dissertation, and I propose a model for analyzing vital signs using OCL, the OMG's standard mathematical specification language. In addition, the proposed model can be confirmed the applicability by figuring out the consumption of calories using ECG data.