• 제목/요약/키워드: notion of nature

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상대적(相對的) 위험(危險)과 추계적(推計的)-통계적(統計的) 우세법칙(優勢法則) (Relative Risk Aversion and Stochastic-Statistical Dominance)

  • 이대주
    • 대한산업공학회지
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    • 제15권2호
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    • pp.33-44
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    • 1989
  • This paper presents stochastic-statistical dominance rules which eliminate dominated alternatives thereby reduce the number of satisficing alternatives to a manageable size so that the decision maker can choose the best alternative among them when neither the utility function nor the probability distribution of outcomes is exactly known. Specifically, it is assumed that only the characteristics of the utility function and the value function are known. Also, it is assumed that prior probabilities of the mutually exclusive states of nature are not known, but their relative bounds are known. First, the notion of relative risk aversion is used to describe the decision maker's attitude toward risk, which is defined with the acknowledgement that the utility function of the decision maker is a composite function of a cardinal value function and a utility function with-respect to the value function. Then, stochastic-statistical dominance rules are developed to screen out dominated alternatives according to the decision maker's attitude toward risk represented in the form of the measure of relative risk aversion.

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학교 수학에서의 '증명' (Proof' in school mathematics)

  • 조완영;권성룡
    • 대한수학교육학회지:수학교육학연구
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    • 제11권2호
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    • pp.385-402
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    • 2001
  • The purpose of this study is to conceptualize 'proof' school mathematics. We based on the assumption the following. (a) There are several different roles of 'proof' : verification, explanation, systematization, discovery, communication (b) Accepted criteria for the validity and rigor of a mathematical 'proof' is decided by negotiation of school mathematics community. (c) There are dynamic relations between mathematical proof and empirical theory. We need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of the notion of proof. 'proof' in school mathematics should be conceptualized in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof 'proof' has not been taught in elementary mathematics, traditionally, Most students have had little exposure to the ideas of proof before the geometry. However, 'proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades, in all mathematics.

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초등학교에서의 증명지도 (The Teaching of 'proof' in Elementary Mathematics)

  • 조완영
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제4권1호
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    • pp.63-73
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    • 2000
  • The purpose of this paper is to address He possibility of the teaching of 'proof' in elementary mathematics, on the assumption that proof in school mathematics should be used in the broader, psychological sense of justification rather than in the narrow sense of deductive, formal proof. 'Proof' has not been taught in elementary mathematics, traditionally. Most students have had little exposure to the ideas of proof before the geometry. However, 'Proof' cannot simply be taught in a single unit. Rather, proof must be a consistent part of students' mathematical experience in all grades. Or educators and mathematicians need to rethink the nature of mathematical proof and give appropriate consideration to the different types of proof related to the cognitive development of a notion of proof.

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Interpretations of Negative Degree Sentences and Questions

  • Kwak, Eun-Joo
    • 영어영문학
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    • 제56권6호
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    • pp.1135-1161
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    • 2010
  • The interpretations of degree expressions require the postulation of new entities to represent degrees. Diverse entities such as degrees, intervals, and vectors are adopted for degree expressions. Positive degree sentences and questions are properly construed with the introduction of these entities, but their negative counterparts need more consideration. Negative degree sentences show dual patterns of entailments depending on contexts, and negative degree questions are unacceptable, making weak islands. To explicate the distinct nature of negative degree sentences and questions, Fox & Hackl (2006) provide an analysis based on degrees while Abrusan & Spector (2010) suggest a proposal in interval readings of degree expressions. I have pointed out the theoretical problems of these analyses and proposed an alternative in the framework of the vector space semantics, following Winter (2005). Bi-directional scales in vector space fit well with the dual patterns of negative degree sentences, and the notion of a reference vector is useful to accommodate the contextual influence in negative degree sentences and to deal with the unacceptability of negative degree questions.

동(東)아프리카 지역(地域)에서 광범위(廣範圍)하게 착용(着用)하는 Kanga개념(槪念) 연구(硏究) (A Study on Kanga Fundanental Notion of Apparel Widely Throughout East Africa)

  • 강은숙
    • 패션비즈니스
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    • 제8권4호
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    • pp.104-116
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    • 2004
  • Kanga is a type of cotton clothes with splendid patterns that East African women throw on their bodies. It first appeared in the East African shores in the mid-nineteenth century. A new style of squared handkerchiefs brought to Africa by Portuguese merchants for the first time was referred as to leso of which early designs were in a basic form of white dots on dark background. Consumers called such material by kanga as they began mentioning its craftiness and comparing its elegant nature to a sociable red rooster and graceful feathers. From the early 1990s, Swahili characters have been embroidered in designs of kanga, mainly consisted of proverbs. Kenya's kanga products are widely known and well represented whereas Tanzania makes the best use of it for political and social events. Fascinating and practical kanga has established its position as an essential part of East African cultures that is being well received as a fashion style there in these days.

Advancing Mathematical Activity: A Practice-Oriented View of Advanced Mathematical Thinking

  • Rasmussen, Chris;Zandieh, Michelle;King, Karen;Teppo, Anne
    • 한국수학교육학회지시리즈E:수학교육논문집
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    • 제18권2호
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    • pp.9-33
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    • 2004
  • The purpose of this paper is to contribute to the dialogue about the notion of advanced mathematical thinking by offering an alternative characterization for this idea, namely advancing mathematical activity. We use the term advancing (versus advanced) because we emphasize the progression and evolution of students' reasoning in relation to their previous activity. We also use the term activity, rather than thinking. This shift in language reflects our characterization of progression in mathematical thinking as acts of participation in a variety of different socially or culturally situated mathematical practices. We emphasize for these practices the changing nature of student' mathematical activity and frame the process of progression in terms of multiple layers of horizontal and vertical mathematizing.

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규칙에 기초한 마스크 레이아웃 변환 시스템의 설계 및 구현 (Design and Implementation of Rule-based Mask Layout Transformation System)

  • 이재황;전주식
    • 전자공학회논문지A
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    • 제30A권9호
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    • pp.46-58
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    • 1993
  • Owing to the nature of locality in mask layouts, it appears that most mask layout problems can be solved by transforming a part of the given mask layout into a better layout segment continuously toward a global suboptimal solution. This notion of local transformation addresses major weak points of existing mask layout processing systems, which lack both extensibility and unifiability. This paper attempts to elaborate upon developing a new rule-based mask layout transformation system wherein most of the mask layout problems can be solved under the unified framework of local mask layout transformation. The rule-based mask layout transformation system is applicable to various mask layout problems such as net extraction, mask layout compaction, mask layout editing, and design rule checking. The experimental results show that the rule-based expert system approach is an efficient means of solving those mask layout problems, and thus confronting major drawbacks of existing layout processing systems.

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COMMUTING ELEMENTS WITH RESPECT TO THE OPERATOR Λ IN INFINITE GROUPS

  • Rezaei, Rashid;Russo, Francesco G.
    • 대한수학회보
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    • 제53권5호
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    • pp.1353-1362
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    • 2016
  • Using the notion of complete nonabelian exterior square $G\hat{\wedge}G$ of a pro-p-group G (p prime), we develop the theory of the exterior degree $\hat{d}(G)$ in the infinite case, focusing on its relations with the probability of commuting pairs d(G). Among the main results of this paper, we describe upper and lower bounds for $\hat{d}(G)$ with respect to d(G). Here the size of the second homology group $H_2(G,\mathbb{Z}_p)$ (over the p-adic integers $\mathbb{Z}_p$) plays a fundamental role. A further result of homological nature is placed at the end, in order to emphasize the influence of $H_2(G,\mathbb{Z}_p)$ both on G and $\hat{d}(G)$.

산업부산물을 이용한 식생용 포러스콘크리트의 물성평가에 관한 실험적 연구 (An Experimental Study on the Evaluation of Physical Properties of Planting Porous Concrete using Industrial By-products.)

  • 박승범;이택우;권혁준;이봉춘;이준
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.929-934
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    • 2001
  • As the notion of environment protection changes throughout the world, construction engineers, as part of the effort to resolve environmental problems, have been actively doing research on environmental friendly porous concrete using large and non-uniform aggregate. Concrete having a great deal of continuous porosity enable water and air to pass freely through firmly hardened material, allowing necessary nutrients to reach roots of vegetation, thereby sustaining them. It is possible to prevent the exhaustion of natural resources by recycling waste concrete and industrial by-products, to reduce damage caused by the destruction of nature through effective management of natural resources, to preserve the natural environment and vegetation in urban areas by activating the soil, protecting the underground ecology system, and growing garden plants through the application of environmentally friendly concrete.

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협력형 개체 수 동역학에 대한 1900년대 연구 (Researches in 1900's on cooperative population dynamics)

  • 장정욱;심성아
    • 한국수학사학회지
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    • 제33권3호
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    • pp.167-177
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    • 2020
  • Cooperative behavior may seem contrary to the notion of natural selection and adaptation, but is widely observed in nature, from the genetic level to the organism. The origin and persistence of cooperative behavior has long been a mystery to scientists studying evolution and ecology. One of the important research topics in the field of evolutionary ecology and behavioral ecology is to find out why cooperation is maintained over time. In this paper we take a historical overview of mathematical models representing cooperative relationships from the perspective of mathematical biology, which studies population dynamics between interacting biological groups, and analyze the mathematical characteristics and meanings of these cooperative models.