• 정보학연구
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• 제12권3호
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• pp.1-6
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• 2009

This paper has focused on the development of an educational sensor network (ESN) based on wireless sensor networks(WSN) and pervasive monitoring systems for students' activity during scientific experiments. A number of WSN systems have been proposed with integrated wireless transmission, mounted sensor boards and local processing. However, there is no trail to employ WSN on the educational field. In this paper, to facilitate research and development using wireless sensor network and multi-sensor data fusion, the educational sensor network (ESN) hardware development platform is presented. The ESN project is conducted over one semester time period (Spring Semesters). It involves approximately twenty middle school students who enrolled a gifted program in Kongju National University. Though under prepared, these students are in general highly motivated to learning specially when presented with the ESN project. An ESN project such as this is expected to provide an excellent means for teaching and learning scientific and mathematical principles.

• 환경위생공학
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• 제17권1호
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• pp.52-56
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• 2002

The study was carried out to evaluate the characteristics of biodegradation by Pseudomonas putida G7 in soil column. The reactor system was used to investigate mass transfer of VOCs as Toluene in a column of unsaturated soil. Determination of the fate of VOCs in unsaturated soil is necessary to evaluate the feasibility of natural attenuation as a VOCs remediation strategy. The objective of this study was to develop a mechanistically based mathematical model that would consider the interdependence of VOC transport, microbial activity, and sorptive interactions in a moist, unsaturated soil. Because the focus of the model was on description of natural attenuation, the advective VOCs transport that is induced in engineered remediation processes such as vapor extraction was not considered. It can be concluded that the coefficient for gas liquid mass-transfer was found to be a key parameter controlling the ability of bacteria to VOCs. Finally, it appeared that bioremediation technology of VOCs which are difficult to be decomposed by chemical methods.

• 대한수학교육학회지:수학교육학연구
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• 제8권2호
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• pp.621-634
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• 1998

Emthusiasm about the introduction of computers into mathematics education is widespred. But, the perspectives about the relationship between mathematics education and computer are diverse. The purpose of this study is to examine theoretical background for using computers in mathematics education. In spite of the pedagogical possibilities of computers. only a small minority of mathematics teachers are using computers in mathematics classroom. It is natural to seek this obstacles within theoretical background of the teachers who manage computers, In this study, We discuss the problems in the two sides. First, due to increased computer activity, relationship of mathematics in school with mathematics in society is changing. It is tension between academic mathematics and practical mathematics. School mathematics have to be changed toward stressing practical mathematics. Second problem is the dialectical relationship between the individual and the collective. While maintaining a respect for the individuality of student contributions. We take into account the social dimension of mathematical meaning-making. We discussed theoretical clarification of work collaborative learning. We propose the case study for the roles of computer in collaborative mathematics learning.

• 한국연초학회지
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• 제15권1호
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• pp.90-97
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• 1993

1. Average moisture content of tobacco in BIB silo was about 19: 1% until 4hours conditioned time, and then moisture variation of tobacco after 2hr conditioned was very small. 2. Application of mathematical model for ordering system. 1) The constant K in the exponential equation varies inversely with both relative humidity and equilibrium moisture. 2) Time needed to order blending tobacco leaves with standard moisture from bulking and blending silo was 4 hours. 3) Reconstituted tobacco sheet had higher moisture absorption ratio than Oriental and Burley tobacco. 4) For minimize of conditioning time in BIB silo, the values of K and Mo given in this study can be used in equation(1) to calculate moisture absorption ratio and optimum conditioning time. 3. Average moisture content and water activity of conditioned tobacco for 4 hours in BIB silo was about 20% and 0.65. In this condition. microbial life will inhibite 4. Physical properties of conditioned tobacco in bulking and blending silo for 4hours was virtually no change.

• 대한의용생체공학회:의공학회지
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• 제15권3호
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• pp.295-304
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• 1994

This paper describes some preliminary attempts to formulate simple mathematical models of the transmission dynamics of HIV infection in homosexual communities. In conjunction with a survey of the available epidemiological data on HIV infection and the incidence of AIDS, the model is used to assess how various processes influence the course of the initial epidemic following the introduction of the virus. Models of the early stages of viral spread provide crude methods for estimating the basic reproductive rate of the virus, given a knowledge of the incubation period of AIDS and the initial doubling time of the epidemic. More complex models are formulated to assess the influence of heterogeneity in sexual activity. This latter factor is shown to have a major effect on the predicted pattern of the epidemic.

• 물과 미래
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• 제29권4호
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• pp.109-118
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• 1996

신경망이론은 분산기억성질과 병렬국소처리를 수행하는 뇌의 활동을 이론화한 수학모형이다. 이러한 신경망이론의 장점은 분류문제, 대규모로 결합된 최적화문제, 비선형 사상문제 등에서 잘 나타나므로, 이 점을 이용하여 복잡한 강우의 예측을 시도하였다. 신경망이론을 적용하기 위해서 연속적인 값으로 표시되는 입력자료와 출력자료를 학습한 후 강우예측을 시행할 수 있는 다층신경망 모형을 구성하였다. 신경망이론에 의한 강우예측은 서울지역과 소양강유역의 1 시간 대위 강우자료에 적용하였다. 그 결과는 대체로 만족할 만하였다. 따라서 신경망이론은 양질의 자료가 충분히 확보될 경우복잡한 강우현상을 잘 예측할 것으로 기대된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권9호
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• pp.1596-1612
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• 2011

Coordinated Multi-Point (CoMP) transmission / reception is being studied in Long Term Evolution-Advanced (LTE-A) for future evolution of the $3^{rd}$ Generation Partnership Project (3GPP) LTE. Support of soft handover is essential for improving the performance of cell edge users. CoMP provides a natural framework for enabling soft handover in the LTE system. This paper evaluates the soft handover gain in LTE-A downlink. Mathematical analysis of signal to interference plus noise ratio (SINR) gain and the handover margins for soft handover and hard handover are derived. CoMP system model is developed and an inter-cell and intra-cell interference model is derived, taking into account the pathloss, shadowing, cell loading, and traffic activity. Reference signal received power (RSRP) is used to define the triggers and the measurements for soft handover. Our results indicate that parameter choices such as handover margin and the CoMP set size impact CoMP performance gain.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.366-370
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• 2005

The construction environment is dynamic in nature and is characterized by various degrees of uncertainties. The uncertainties such as lack of coordination, non availability of resources, condition of temporary structures and varying weather conditions have a significant impact on estimating the duration of activities. These are subjective, vague and imprecisely defined and are expressed in subjective measures rather than mathematical terms. Conventionally, various quantitative techniques such as CPM and PERT have emerged in construction industry. These techniques cannot solve the above problems and rely on human experts which may not always be possible. In such situations Artificial Intelligence tools such as fuzzy sets and neural networks handle such variables and provide global strategies. The present paper evaluates the effect of qualitative factors to identify the activity duration using new intelligent approach. The results are compared with conventional methods for effective project management. A case study is considered to demonstrate the applicability of fuzzy logic for project scheduling.

• 영재교육연구
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• 제22권3호
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• pp.619-637
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• 2012

girih 타일링은 비주기적이면서도 규칙적인 구조를 가진 타일링으로, 최근 '이슬람 사원 장식에 숨어있는 수학의 비밀'로 주목받고 있다. 본 연구에서는 이를 소재로 하여 비주기적인 규칙성 안에 숨어 있는 수학이 만들어내는 유용성과 아름다움을 체험할 수 있는 초등 수학영재 프로그램을 개발 적용하고 그 결과를 분석하는 데 목적을 두었다. 개발한 초등수학영재 프로그램은 '이슬람 문양 속 girih의 비밀을 찾아서'이며, Renzulli의 3부 심화학습 형식에 따라 적용하였다. 이 프로그램은 대전광역시 유성구에 소재하고 있는 D 초등학교 5, 6학년 통합영재반 6명에게 적용한 결과를 토대로 수정, 보완 하였으며 개발된 프로그램 및 학습 자료는 초등수학영재 교육을 위한 소재 개발과 방법에 있어 도움이 될 것으로 기대한다.

• 대한수학교육학회지:수학교육학연구
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• 제25권2호
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• pp.225-240
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• 2015

본 연구에서는 중점연결정리의 사각형으로의 확장을 소재로 학교수학에서 다루어지는 증명의 대표성에 대해 고찰하였다. 다양한 사각형을 생각하고, 그에 맞는 중점연결정리의 확장을 증명하였으며, 이들 증명 간의 관계를 파악하여 학교수학에서의 증명이 대표성을 가짐을 보였다. 한편, 이러한 내용에 기초한 실태조사에서 학생들은 사각형 종류의 일부만을 찾았으며, 찾은 사각형 각각에 대한 증명은 쉽게 완성하였으나, 같은 수학적 사실을 증명하고 있음에도 대상 도형이 바뀌면 다른 증명 방법이나 수학적 개념을 사용하는 경향을 보였다. 따라서 증명들 간의 관계를 파악하는 것을 어려워하였다. 이러한 사실들은 구체적 도형에 대한 증명은 할 수 있으나, 증명들 간의 관계를 이해하여 일반화하는 증명의 대표성에 대한 이해는 부족함을 보여준다. 따라서 증명활동이 유기적이고 의미론적으로 이루어질 필요가 있음을 알 수 있다.