• Title/Summary/Keyword: Russell

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Thermal conductivity of PLA-bamboo fiber composites

  • Takagi, Hitoshi;Kako, Shuhei;Kusano, Koji;Ousaka, Akiharu
    • Advanced Composite Materials
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    • v.16 no.4
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    • pp.377-384
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    • 2007
  • 'Green' composites were fabricated from poly lactic acid (PLA) and bamboo fibers by using a conventional hot pressing method. The insulating properties of the PLA-bamboo fiber 'green' composites were evaluated by determination of the thermal conductivity, which was measured using a hot-wire method. The thermal conductivity values were compared with theoretical estimations. It was demonstrated that thermal conductivity of PLA-bamboo fiber 'green' composites is smaller than that of conventional composites, such as glass fiber reinforced plastics (GFRPs) and carbon fiber reinforced plastics (CFRPs). The thermal conductivity of PLA-bamboo fiber 'green' composites was significantly influenced by their density, and was in fair agreement with theoretical predictions based on Russell's model. The PLA-bamboo fiber composites have low thermal conductivity comparable with that of woods.

직관주의 논리

  • 이승온;김혁수;박진원;이병식
    • Journal for History of Mathematics
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    • v.12 no.1
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    • pp.32-44
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    • 1999
  • This paper is a sequel to [8]. Development of modern logic was initiated by Boole and Morgan. Boolean logic is one of their completed works. Cantor created the set theory along with cardinal and ordinal numbers. His theory on infinite sets brought about a remarkable development on modern mathematical theory, but generated many paradoxes (e.g. Russell Paradox) that in turn motivated mathematicians to solve them. Further, mathematicians attempted to construct sound foundations for Mathematics. As a result three important schools of thought were formed in relation to fundamentals of mathematics for the resolution of paradoxes of set theory, namely logicism developed by Russell and Whitehead, intuitionism lead by Brouwer and formalism contended by Hilbert and Bernays. In this paper, we examine the logic for intuitionism which is originated by Brouwer in 1908 and study Heyting algebra.

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Performance Evaluation of the ACD Models for Analysing the Transaction Data of the KOSPI Stocks (주식 거래 자료 분석을 위한 ACD 모형 성능 비교)

  • Kim, Sahm;Jung, Da-Woon
    • Communications for Statistical Applications and Methods
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    • v.16 no.1
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    • pp.21-29
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    • 2009
  • Engle and Russell (1998) proposed the ACD(Autoregressive Conditional Duration) model to explain the relationship between the prices and the duration times of the stocks. In this paper, we first introduce the various types of the ACD models such as the linear ACD, log ACD and Box-Cox ACD models and we evaluate the performance of the models for analysing the transaction data of the stocks in Korea.

Measurement of Emotional Transition Using Physiological Signals of Audiences (관객의 생체신호 분석을 통한 감성 변화)

  • Kim, Wan-Suk;Ham, Jun-Seok;Sohn, Choong-Yeon;Yun, Jae-Sun;Lim, Chan;Ko, Il-Ju
    • The Journal of the Korea Contents Association
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    • v.10 no.8
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    • pp.168-176
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    • 2010
  • Audience observing visual media with care experience lots of emotional transition according to characteristics of media. Enjoy, sadness, surprising, etc, a variety of emotional state of audiences is often arranged by James Russell's 'A circumplex model of affect' utilized on psychology. Especially, in various emotions, 'Uncanny' mentioned by Sigmund Freud is represented a sharp medium existing in a crack of clearly emotional conception. Uncanny phenomenon is an emotional state of changing from unpleasant to pleasant on an audience observing visual media is been aware of immoral media generally, therefore, because this is a positive state on a social taboo, we need to analyze with a scientific analysis clearly. Therefore, this study will organize James Russell's 'A circumplex model of affect' and uncanny phenomenon, will be progressed to establish a hypothesis about a state of uncanny on audiences observing visual media and analyze results of the physiological signals experiment based on ECG(Electronic Cardiogram), GSR(Galvanic Skin Response) signals with distribution, distance, and moving time in a circumplex model of affect.

Craniopharyngiomas : Radiological Differentiation of Two Types

  • Lee, In Ho;Zan, Elcin;Bell, W. Robert;Burger, Peter C.;Sung, Heejong;Yousem, David M.
    • Journal of Korean Neurosurgical Society
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    • v.59 no.5
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    • pp.466-470
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    • 2016
  • Objective : To determine imaging features that may separate adamantinomatous and papillary variants of craniopharyngiomas given that tumors with adamantinomatous signature features are associated with higher recurrence rates, morbidity, and mortality. We specifically reviewed calcification on CT, T1 bright signal intensity, and cystic change on T2 weighted images for differentiating these two types. Methods : We retrospectively reviewed the MRI and CT studies in 38 consecutive patients with pathologically proven craniopharyngiomas between January 2004 and February 2014 for the presence of calcification on CT scans, bright signal intensity on T1 weighted images, and cystic change on T2 weighted images. Results : Of the 38 craniopharyngiomas, 30 were adamantinomatous type and 8 were papillary type. On CT scans, calcification was present in 25 of 38 tumors. All calcified tumors were adamantinomatous type. Twenty four of 38 tumors had bright signal intensity on T1 weighted images. Of these 24 tumors, 22 (91.7%) were adamantinomatous and 2 were papillary type. Cystic change on T2 weighted images was noted in 37 of 38 tumors; only 1 tumor with papillary type did not show cystic change. Conclusion : T1 bright signal intensity and calcification on CT scans uniformly favor the adamantinomatous type over papillary type of craniopharyngioma in children. However, these findings are more variable in adults where calcification and T1 bright signal intensity occur in 70.6% and 58.8% respectively of adult adamantinomatous types of craniopharyngiomas.

Analysis of influencing on Inefficiencies of Korean Banking Industry using Weighted Russell Directional Distance Model (가중평균 러셀(Russell) 방향거리함수모형을 이용한 은행산업의 비효율성 분석)

  • Yang, Dong-Hyun;Chang, Young-Jae
    • Journal of Digital Convergence
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    • v.17 no.5
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    • pp.117-125
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    • 2019
  • This study measured inefficiencies of Korean banks with weighted Russell directional distance function, WRDDM, for the years of 2004-2013. Checking contributions of inputs and outputs to these inefficiencies, we found that non-performing loan as undesirable output was the most influential factor. The annual average of inefficiencies of Korean banks was 0.3912, and it consisted of non-performing loan 0.1883, output factors 0.098 except non-performing loan, input factors 0.098. The annual average inefficiency went sharply up from 0.2995 to 0.4829 mainly due to the sharp increase of inefficiency of non-performing loan from 0.1088 to 0.2678 before and after 2007-2008 Global financial crisis. We empirically showed the non-performing loan needed to be considered since it was the most important factor among the influential factors of technical inefficiency such as manpower, total deposit, securities, and non-performing loan. This study had some limitation since we did not control financial environment factor in WRDDM.