• 한국수학사학회지
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• 제28권5호
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• pp.249-262
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• 2015

Simon Stevin, a mathematician active in the Netherlands in early seventeenth century, parlayed his mathematical talents into improving navigation skills. In 1605, he introduced a technique of calculating the distance of loxodrome employed in long-distance voyages in his book, Navigation. He explained how to calculate distance by 8 different angles, and even depicted how to make a copper loxodrome model for navigators. Particularly, Stevin clarified in the 7th copper loxodrome model on the unique features of equiangular spiral curve that keeps spinning and gradually accesses from the vicinity to the center. These findings predate those of Descartes on equiangular spiral curve by more than 30 years. Navigation, a branch of actual mathematics devised for the survival of sailors on the bosom of the ocean, was also the first step to the discovery of new mathematical object.

• 한국과학교육학회지
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• 제10권1호
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• pp.119-125
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• 1990

The results of the analyses of 431 doctoral disserations of science education (Dissertation Abstracts International. 1980-1984) are as follows : 1. It was recognized that many countries as well as USA(e.g. Canada, Nigeria, Saudi Arabia, South Africa, Taiwan, Thailand, The Netherlands etc.) have deep interest in science education. 2. About 60% of dissertations had been focused on middle school (junior and senior)and college students as the subject of investigation. 3. Disciplines of science concerning the subject showed general science (35.6%), biology (18.3%), physics (11.4%), chemistry (11.4%), earth science (4.6%), and others (18.7%). 4. The number of dissertations belonging to experimental research was over 60 more than that of dissertations belonging to theoretical research. 5. In methodology of research, examination, test, questionaire were general method, and the field of research was focused mainly on the academic achievement.

• 한국유기농업학회:학술대회논문집
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• 한국유기농업학회 2001년도 심포지엄
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• pp.163-178
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• 2001

The last few nears have seen significantly increased interest in organic food. Organic food is still a small but growing part of the food industry with an identity defined and protected by law. Its existence provides an element of consumer choice. To obtain consumer confidence and, product credibility and transparency in the organic market, organic legislation and certification is needed, To facilitate export of organic products, harmonization of the organic legislation is favoured. The IFOAM accreditation programme has already achieved very much in this respect. Several national regulation, such as the NOP(USA) and EC2092/91(European Union) have already complied with the IFOAM basic standards. But in many countries there is still a lack of national legislation on organic agriculture. Because of the fast globalisation, organic agriculture is facing major challenges for international trade, so it is very important to consider the future development and certification of organic produce in all countries.

• ALGAE
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• 제22권1호
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• pp.31-36
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• 2007

The gametophytic filaments of two genetically distinct taxa of Bangia from New Zealand showed unusual rhizoidal development in comparative culture experiments. In the past Bangia has been reported to possess simple, colourless rhizoids that extend from the basal cells of the unbranched filaments, whereas in this study the rhizoids observed became pigmented and multicellular. A reversal of growth direction occurred and filamentous extensions developed from the rhizoids under some culture conditions. These extensions were either prostrate or resembled new gametophytic filaments. This is the first report for filamentous members of the Bangiales of the development of such stolon-like rhizoids, apparently serving as a form of vegetative reproduction.

• 천문학회보
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• 제36권2호
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• pp.109.2-109.2
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• 2011

We have carried out a multi-epoch, simultaneous 22GHz $H_2O$ and 44GHz class I $CH_3OH$ maser survey of 109 low-mass protostars. $H_2O$ maser emission was detected in 23 sources, while $CH_3OH$ maser emission in 12 sources. Eight of the $CH_3OH$ detected sources are new detections. For comparison, only four low-mass protostars have been previously found to emit the maser emisison. We investigate difference between the properties of the two masers, such as relative velocity with respect to molecular gas and variability. We also compare the isotropic luminosities of both masers with the bolometric luminosity of the central star.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제8권3호
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• pp.115-121
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• 2004

This article describes the first results gained from a problem solving test that was administered to grade 4 students in the Netherlands. The students involved are all high achievers in mathematics. The analysis of the student responses gives cause for concern. The often-heard belief that teachers do not need to worry about the better students is clearly in need of revision. It turned out that when high achievers in mathematics are challenged to take on non-typical problems, their abilities are more limited than expected. The study revealed that the students wrote down hardly anything on their scrap paper to solve certain problems. Also it was found that they were not very persistent in their looking for a solution. In this paper we illustrate these first findings by discussing the results of one of the test problems.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2006년도 추계학술발표대회 논문집
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• pp.448-451
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• 2006

Multi-residential housing in Korea has many problems basically because maintenance, management, and remodelling have been done without considering building elapse and residents' needs. Residential open building has been suggested as one of the solutions. Even though the techniques have been actively developed for residential open building in Japan and the Netherlands, some obstacles are still existing. Especially in Korea, due to the lack of studies for facilitating residential open building, the development and popularization of residential open building are delayed. With the concern that the facilitation of process and systems is as important as technical development, the evaluation of process and systems is needed for promoting residential open building. As result, strong investigation of current situation can offer basic foundation to facilitate residential open building. The purpose of this study is to propose plans to facilitate residential open building in Korea through a comparative study between Korean and Japanese system.

• 한국디지털건축인테리어학회논문집
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• 제5권1호
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• pp.32-39
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• 2005

Even though geographical drawbacks of Netherlands, the De Stiji Movement has been acting extensively as a composite arts movement. Furthermore, because this movement has influenced on even field of architecture, Walter Gropius, who had led to establish the modern architecture at that time, was not also able to be excluded from the influence of De Stiji movement. As a result, his works after 1922 when De Stijl movement had been acting vividly, shows a part of De Stijl style and definitely has a difference via-a-via early of his works. Therefore, this study in this point of view is on the purpose of how De Stijl Movement influenced on Gropius' works as the ideology of place and concepts in the period of both De Stijl Movement and Modern architecture style were being formed together. Especially, this study will analyze Dessau Bauhaus Building, which is the most influenced by De Stijl Style in Gropius' works, into the way of how De Stijl. was embodied to this building.

• 천문학회보
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• 제43권1호
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• pp.44.3-45
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• 2018

Magnetic fields affect star formation in a broad range of scales from parsec to hundreds au. In particular, interferometric observations and ideal magneto-hydrodynamic (MHD) simulations have reported that formation of a rotation-supported disk at the earliest young stellar objects (YSOs) is largely suppressed by magnetic fields aligned to the rotational axis of YSOs: magnetic braking. Our recent ALMA observations toward L1448 IRS 2, which has a rotation detected and its magnetic fields aligned to the rotation axis (poloidal fields) in ~500 au scales, show that the fields switch to toroidal at the center in ~100 au scales. This result suggests that magnetic braking may not be so catastrophic for early disk formation even in YSOs with magnetic fields aligned to the rotational axis.

• 제어로봇시스템학회논문지
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• 제14권6호
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• pp.587-594
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• 2008

In this paper, an efficient integer ambiguity resolution method for GNSS attitude determination system is described. The proposed method solves the integer least-squares with quadratic equality constraints(ILSQE) problem and shows an expansion of the LAMBDA method can be used to solve it. The solution of ILSQE is shown and an efficient implementation with a LAMBDA based method is given. The method is compared with some other methods. The results of static and dynamic tests show the dramatic improvement of the success rates of integer ambiguity resolution.