• Journal of Educational Research in Mathematics
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• v.18 no.1
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• pp.103-121
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• 2008

The primary purpose of this study was to gather knowledge about $5^{th},\;6^{th},\;and\;7^{th}$ graders' proportional reasoning ability by investigating their reactions and use of strategies when encounting proportional or nonproportional problems, and then to raise issues concerning instructional methods related to proportion. A descriptive study through pencil-and-paper tests was conducted. The tests consisted of 12 questions, which included 8 proportional questions and 4 nonproportional questions. The following conclusions were drawn from the results obtained in this study. First, for a deeper understanding of the ratio, textbooks should treat numerical comparison problems and qualitative prediction and comparison problems together with missing-value problems. Second, when solving missing-value problems, students correctly answered direct-proportion questions but failed to correctly answer inverse-proportion questions. This result highlights the need for a more intensive curriculum to handle inverse-proportion. In particular, students need to experience inverse-relationships more often. Third, qualitative reasoning tends to be a more general norm than quantitative reasoning. Moreover, the former could be the cornerstone of proportional reasoning, and for this reason, qualitative reasoning should be emphasized before proportional reasoning. Forth, when dealing with nonproportional problems about 34% of students made proportional errors because they focused on numerical structure instead of comprehending the overall relationship. In order to overcome such errors, qualitative reasoning should be emphasized. Before solving proportional problems, students must be enriched by experiences that include dealing with direct and inverse proportion problems as well as nonproportional situational problems. This will result in the ability to accurately recognize a proportional situation.

• Journal of the Korean School Mathematics Society
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• v.11 no.4
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• pp.609-627
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• 2008

The purpose of this research was to investigate the relationship between the students' strategy types and the recognition for proportional situations. The students' strategy types which were based on the results of ratio and proportion tests were divided into an additive type, a multiplicative type, and a formal type. This research analyzed the students' activities of categorization when were given the proportional problems and nonproportional problems to the students. And it also explored how to develop students' recognizing for the discrimination between the proportional situations and nonproportional situations. The results was the following. First, the students didn't discriminate the proportional situations and the nonproportional situations in the initial state but they came to discriminate little by little. Secondly, the students didn't discriminate the direct proportions and the inverse proportions until the last stage. Third, the multiplicative type was outperformed more than the formal type in solving the ratio and proportion problems but the formal type was outperformed more than the multiplicative type in discriminating between proportional situations and nonproportional situations. These results are interpreted as showing that solving ratio and proportion tasks and recognizing proportional situations are different aspects of proportional reasoning and it is necessary to understand multiplicative strategy with formal strategy in recognizing proportional situations.

• Defense and Technology
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• no.8 s.174
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• pp.22-29
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• 1993

자주국방을 위해서는 최소한 우리의 해로는 우리가 효과적으로 방어할 수 있는 함정과 무기체계를 갖추어 적절한 해상세력을 유지해야 합니다 그러나 우리는 지금까지 해군을 지상군에 종속시키려는 정책을 퍼 왔었습니다 이제 국방부는 육.해.공 3군이 균형적으로 발전하는 전략을 구사해야 하며, 인사문제도 각군의 인원수 비례가 아닌 진정한 의미의 균형을 이루는데 힘써야 할 것입니다

• The Microorganisms and Industry
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• v.10 no.1
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• pp.7-9
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• 1978

계란을 비롯하여 모든 축산식품중에서 잔류항생물질이 문제가 되고 있는 것은 비단 우리나라 만은 아닌 것이므로 새삼스럽게 큰 사회 문제로 파문을 일으킬 것은 없지만 사태의 중요성에 대하여는 진지하게 관심을 갖어야 한다. 그러한 이유중의 하나로 최근에 나타난 중요한 사태는 양계및 양축의 양적인 수의 증가는 사료의 소비량의 증가와 비례하지만 사료에 첨가하는 항생물질의 소비량은 해마다 몇번씩 이례적으로 증가하고 있는 사실이다. 그러므로 국민의 보건과 밀접한 관계가 있는 양계업에 종사하는 여러분을 위해서 이 기회에 알아 두어야 할 몇가지를 간략하게 소개하고저 한다.

• School Mathematics
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• v.10 no.4
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• pp.603-623
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• 2008

The purpose of this research was to gain a better understanding of the characteristics of students' mathematical representations using additive strategy in ratio and proportion tasks. The additive strategy is the erroneous one used most often among the strategies reported in solving ratio and proportion tasks. It is a problem solving strategy that preserves the difference from one ratio to another. Students' additive strategies were categorized into four parts: subtracting without considering units of quantities, comparing the numbers that represent the whole subtracted from the part and same part, adding the difference, and subtracting the difference. In order to change from additive strategy to multiplicative strategy, the researcher asked to find out the unit quantity and found the characteristics of students' mathematical notations in the following: Firstly, the students made the number which they wanted by multiplying and adding same numbers. Secondly, they represented the mid-points between natural numbers. Thirdly, they related $a{\div}b$ to decimal number, not $\frac{a}{b}$. Fourthly, they were inclined to divide the larger number with the smaller number without understanding the context of the problem. These results are interpreted as showing that lower level of performance in the dividing operation with the notations of fraction hinders the transformation from additive strategy to multiplicative strategy.

• 대학교육
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• s.144
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• pp.54-58
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• 2006

연구윤리 문제를 거론하는 일은, 지금까지 행해진 연구 부정행위를 어떻게 처리할 것인가가 아닌 예방적 차원에서 어떻게 연구 부정행위를 방지할 것인가에 초점이 모아져야 한다. 얼마 전 발생한 '줄기세포 조작 사건'도 구성원들의 도덕적 해이에서 비롯된 것이라는 지적이다. 국력이 신장되고 연구역량이 커진 것과 비례하여 연구윤리에 대한 경각심과 경계심도 키워 나가야 한다. 연구를 시작하는 단계에서부터 연구윤리의 중요성을 깨닫고 생활화 할 수 있어야 하며, 이러한 변화는 또한 앞으로의 연구의욕을 꺾거나 과거의 연구성과를 무차별적으로 불신하게 되는 부작용을 잉태하지 말아야 한다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.2B
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• pp.82-89
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• 2008

Mobile IP is the basic solution to provide host mobility, whereas network mobility refers to the concept of collective mobility of a set of nodes. In a network mobility scenario, mobile networks can be nested in a hierarchical form. That situation is referred to a nested mobile network Nested mobile networks exhibit the pinball routing problem, which becomes worse in proportion to the number of nested levels in the hierarchy. In this paper, we propose a routing optimization scheme having backward compatibility to the basic network mobility protocol and concerning heterogeneity of nested mobile network, also we perform comparison and analysis of proposed schemes.

• Proceedings of the KOR-KST Conference
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• 1998.10b
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• pp.466-466
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• 1998

도로 교통의 혼잡이 나날이 증가되고 있는 현실 상황에서 이를 해결하기 위한 새로운 도로의 무제한적 건설은 정보의 예산절약, 필요한 도로용지 확보의 어려움, 환경오염 문제 등으로 인해 현실적인 한계에 이르렀다. 따라서, 이러한 도로의 혼잡상황에 효과적으로 대처하기 위해서는 승용차를 이용하고자 하는 수요를 대량수송이 가능한 대중교통 이용수요로 전환시켜야 하며, 이를 위해서는 대중교통의 서비스수준 제고 및 운영 관리 체계 등의 개선이 필요하다. 이를 위한 전략적 및 운영적 측면에서의 대중교통계획은 미래 대중교통수요의 정확한 예측을 전제로 하여 수립되며, 이러한 수요의 예측은 필수적으로 현실을 보다 더 정확하게 묘사해 줄 수 있는 통행배정모형을 필요로 한다. 대중교통 통행배정은 규칙적인 배차시간과 정해진 노선을 운행하는 고정서비스 시스템으로 구성되어 있어서 한 링크 상에서도 여러 개의 운행노선을 고려해야 하기 때문에 승용차 통행배정과는 독립적으로 취급되어 왔으며, 이로 인해 그 동안 많은 연구가 선행되어 있지 않은 실정이다. 본 연구는 교통예측 프로그램 중의 하나인 EMME/2에서 사용하고 있는 대중교통수요 통행배정 모형인 최적전략모형(Optimal Strategy Model)의 단점을 보완하기 위한 것이다. 최적전략모형은 수요 배정시, 최적전략에 속하는 경로들에 대해 단순히 운행횟수에 비례하여 수요를 배정함으로 인해서, 예를 들면 운행횟수는 많지만 환승이 많은 경로에 수요를 많이 배정하는 것과 같은 비현실적인 결과가 발생하기도 한다. 본 연구는 이를 개선하기 위해서, 두 가지 대안을 제시했다. 먼저, 노선배정에 우선되는 최적경로 탐색시 환승노드에서의 환승에 대한 벌점을 그 노선의 운행회수에 줌으로써 환승이 많은 경로에 수요의 배정이 적게 되도록 하는 방법과 두 번째로 수요의 배정시 운행횟수가 아닌 목적지까지의 통행시간과 대시시간에 따른 확률적 배분을 통해 기존 모형의 단점을 보완하고자 했다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.05a
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• pp.256-258
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• 2016

Domestic vehicle demand is growing steadily. In proportion to the increased interest generated by the automobile-related accidents are more frequent. One of the causes of these accidents are caused by vehicle accidents exists tire problems. Users check tire wear with their naked eyes or check the tread and the wear indicator by using a coin. However, such visual judgment cannot be precise and make it possible to identify the time for tire replacement. Therefore, by utilizing visual and objective data rather than incorrect decisions through objective data, we designed a system that accurately and can easily tell whether the tire condition and replacement of the driver.

• The Korean Journal of Air & Space Law and Policy
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• v.26 no.2
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• pp.3-39
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• 2011

People may operate unmanned aerial vehicles (UAVs or drones) thousands of miles from the drone's location. Drones were first used (like balloons) for surveillance. By 2001, the United States began arming drones with missiles and using them to strike targets during combat in Afghanistan. By mid-2010, over forty states and other entities possessed drones, many with the capability of launching missiles and dropping bombs. Each new development in military weapons technology invites assessment of the relevant international law. This Insight surveys the international law applicable to the recent innovation of weaponizing drones. In determining what international law rules govern drone use, the most salient feature is not the fact that drones are unmanned. The fact drones carry no human operator may be the most important new technological breakthrough, but the key feature for international law purposes is the type of weaponry drones carry. Whether law enforcement rules govern drone use depends on the situation and not necessarily who is operating the drone. Battlefield weapons may also be lawfully used before an armed conflict in the following situations: when initiating self-defense under Article 51 of the United Nations Charter; when authorized by the UN Security Council; when a government seeks to suppress internal armed conflict; and, perhaps, when a state is invited to assist a government in suppressing internal armed conflict. The rules governing resort to force in self-defense are found in Article 51 of the UN Charter and a number of decisions by international courts and tribunals. Commentators continue to debate whether drone technology represents the next revolution in military affairs. Regardless of the answer to that question, drones have not created a revolution in legal affairs. The current rules governing battlefield launch vehicles are adequate for regulating resort to drones. More research must be undertaken, however, to understand the psychological effects of deploying unmanned vehicles and the effects on drone operators of sustained, close visual contact with the aftermath of drone attacks.