• 제목/요약/키워드: paradoxical

검색결과 229건 처리시간 0.022초

Chances of Simpson's Paradox

  • Jeon, Jong-Woo;Chung, Han-Yeong;Bae, Jong-Sig
    • Journal of the Korean Statistical Society
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    • 제16권2호
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    • pp.117-127
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    • 1987
  • The Simpson's paradox is a paradoxical phenomenon which might occur when analyzing $2 \times 2$ contingency table. This paper considers the role of probability assignment of the experimental units in reducing the chances of Simpson's paradox. Numerical results are given to illustrate how the chance of Simpson's paradox behaves.

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Parrondo Paradox and Stock Investment

  • Cho, Dong-Seob;Lee, Ji-Yeon
    • 응용통계연구
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    • 제25권4호
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    • pp.543-552
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    • 2012
  • Parrondo paradox is a counter-intuitive phenomenon where two losing games can be combined to win or two winning games can be combined to lose. When we trade stocks with a history-dependent Parrondo game rule (where we buy and sell stocks based on recent investment outcomes) we found Parrondo paradox in stock trading. Using stock data of the KRX from 2008 to 2010, we analyzed the Parrondo paradoxical cases in the Korean stock market.

이동통신 시스템을 위한 "역설적인" ID-Based 키분배 방식 (A "Paradoxical" ID-Based Key Distribution Protocol for Mobile Communication Systems)

  • 최연이;김성덕;양형규;원동호
    • 한국정보보호학회:학술대회논문집
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    • 한국정보보호학회 1995년도 종합학술발표회논문집
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    • pp.307-313
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    • 1995
  • 본 논문에서는 기존에 제안된 이동통신용 키분배 방식의 문제점을 분석하고, Girault가 제안한 자체인증 공개키(Self-certified public keys) 개념을 이용한, 인증자에 기반을 둔(Certification-based) 방식이 아닌 개인식별정보에 기반을 둔(Identity-based) 방식이면서도 사용자가 자신의 비밀키를 선택할수 있는, 이동 퉁신망에 적용가능한 "역설적인" ID-based 키분배 방식을 제안한다. 제안한 방식의 안전성은 고차 잉여류 문제(${\gamma}$$^{th}$ -residuosity problem)와 이산대수(discrete logarithm) 문제에 근거한다. 문제에 근거한다.

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정신장애의 진화유전학적 모델 (Evolutionary Genetic Models of Mental Disorders)

  • 박한선
    • 생물정신의학
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    • 제26권2호
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    • pp.33-38
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    • 2019
  • Psychiatric disorder as dysfunctional behavioural syndrome is a paradoxical phenomenon that is difficult to explain evolutionarily because moderate prevalence rate, high heritability and relatively low fitness are shown. Several evolutionary genetic models have been proposed to address this paradox. In this paper, I explain each model by dividing it into selective neutrality, mutation-selection balance, and balancing selection hypothesis, and discuss the advantages and disadvantages of them. In addition, the feasibility of niche specialization and frequency dependent selection as the plausible explanation about the central paradox is briefly discussed.

EXPLOSION HAZARDS IN TANKS OF HIGH FLASH POINT LIQUIDS

  • Zalosh, Robert
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 1997년도 International Symposium on Fire Science and Technology
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    • pp.203-210
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    • 1997
  • Reports of explosions in cargo and storage tanks of high flash point liquids such as residual fuel oil, asphalt, and oily waste water have shown that these explosions have occurred even when the liquid temperatures are well below the liquid nominal flash point. The reasons for these seemingly paradoxical explosions are reviewed and results of recent laboratory tests are presented to better define the conditions leading to flammable vapor atmospheres in these tanks. The potential effectiveness of various prevention measures are discussed including inerting, monitoring tank vapor concentrations, and periodic cleaning of condensation and deposits on the tank walls and roof.

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고차잉여류 문제와 이산대수 문제에 기반을 둔 역석적인 id-based암호 시스템 (A "Paradoxical" identity-based scheme based on $\gamma^{th}$-residuosity problem and discrete logarithm problem)

  • 박성준
    • 정보보호학회논문지
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    • 제4권2호
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    • pp.90-118
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    • 1994
  • 본 논문에서는 certificatoin-based 방식이 아닌 id-based방식이면서도 사용자가 자신의 비밀키를 선택할 수 있는 역설적인 id-based 방식을 제안한다. 제안한 방식은 Girault가 제안한 self-certified공개키 개념을 id-based방식에 적용한 것이다. 제안한 방식의 안전성은 고차잉여류 문제와 이산대수 문네에 기반을 두고 있다.

청년하위문화에 나타난 Black Leather Jacket 연구 (A Study on Black Leather Jacket in Youth Sub-Culture)

  • 김지선;엄혜정
    • 복식
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    • 제55권2호
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    • pp.92-104
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    • 2005
  • This study aimed to reveal the concept and background of emergence of black leather jacket that began appearing in full-scale among youth sub-culture from 1950's, and to research its styles and aesthetic features on the basis of that. The researcher has intended to a theoretical frame to recreate black leather jacket which has been developing in youth sub-culture style as a resource of new design in modern fashion trend through this study There are 5 styles of black leather jacket in youth sub-culture after 1950's. Firstly, biker style black leather jacket showed ruined war heroes substituting for military uniform. Secondly, rocker style black leather jacket brought the conversion in definition of masculinity. Thirdly, greaser style black leather jacket showed the beauty of uncleanness expressing resistance and violence with tattered dirty materials and excessive metal ornaments. Fourthly, headbanger style black leather jacket was prominent in various and compound decoration due to combination of rocker and hippie features. fifthly, punk style black leather jacket was influenced greatly by Sex Pistols. There are broadly three ecstatic features oi black leather jacket among youth sub-culture. With regard to displaying terrorism, black leather jacket displayed threatening aspects with black color, formative beauty of inverted triangle, additional decoration, and animal & brutal feelings. Paradoxical trophyism showed Nihilism, disorder, and resistance through black color that symbolize bad luck and unstability, trophyism with bad flavor, tattered material effect, and destructive message painting. Masculine eroticism appeared in accordance with pursuing after pleasure and masculine sexuality through exposure of buttocks and focused penis due to jacket's short length, and fetish of black.

말티즈 견에서 발생한 원발성 폐동맥 고혈압증 (Primary Pulmonary Hypertension in a Maltese Dog)

  • 문형선;이승곤;최란;박인철;현창백
    • 한국임상수의학회지
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    • 제24권4호
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    • pp.613-617
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    • 2007
  • 중성화된 1년령 말티즈 개(2.4kg)가 간헐적인 기침, 호흡곤란, 운동 불내성을 주요 증상으로 내원하였다. 신체검사 시 제 2음 모순 분열, 확장기 역류성 잡음이 관찰되었으며, 심장초음파에서 주폐동맥의 확장, 심실 중격 비대를 동반한 우심실 편심성 비대, 심각한 삼첨판 역류증과 폐동맥 역류증(5.4m/sec, 3.4m/sec)이 관찰되었다. 이러한 진단 검사 결과를 바탕으로, 본 증례를 선천성 심장 내 단락, 폐쇄성 폐질환, 그리고 우심계의 압력 과부하 또는 폐혈관계과관류와 관련된 전신질환과 감별하여 원발성 폐동맥 고혈압증으로 잠정진단 하였다. 환자는 furosemide와 aspirin을 투여하여, 산소요법을 실시하였다. 본 증례는 드물게 발생하는 개의 원발성 폐동맥 고혈압이다.

폐쇄성 폐질환에 동반된 성대 운동이상에 의한 기능성 상기도폐색 1예 (A Case of Functional Upper Airway Obstruction Due to Vocal Cord Dysfunction in Obstructive Pulmonary Disease)

  • 오명;김상철;백재중;정연태
    • Tuberculosis and Respiratory Diseases
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    • 제51권3호
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    • pp.270-274
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    • 2001
  • 성대 운동이상에 의한 상기도 폐색은 드문질환으로 저자들은 호흡곤란을 주소로 내원한 61세 여자환자에서 기관지내시경검사와 폐기능검사로 폐쇄성폐질환에 동반된 성대 운동이상에 의한 기능성상기도 폐색증을 확진하고 이완요법(relaxation)과 산소공급으로 증상이 호전되어 퇴원후 외래에서 추적관찰중인 1예를 경험하여 이를 문헌고찰과 함께 보고하는 바이다.

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