• Title/Summary/Keyword: Subject Memory

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An outlier-adaptive forecast method for realized volatilities (이상치에 근거한 선택적 실현변동성 예측 방법)

  • Shin, Ji Won;Shin, Dong Wan
    • The Korean Journal of Applied Statistics
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    • v.30 no.3
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    • pp.323-334
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    • 2017
  • We note that the dynamics of realized volatilities (RVs) are near the boundary between stationarity and non-stationarity because RVs have persistent long-memory and are often subject to fairly large outlying values. To forecast realized volatility, we consider a new method that adaptively use models with and without unit root according to the abnormality of observed RV: heterogeneous autoregressive (HAR) model and the Integrated HAR (IHAR) model. The resulting method is called the IHAR-O-HAR method. In an out-of-sample forecast comparison for the realized volatility datasets of the 3 major indexes of the S&P 500, the NASDAQ, and the Nikkei 225, the new IHAR-O-HAR method is shown superior to the existing HAR and IHAR method.

Clinical Applications of Event-related Potentials (사건관련전위의 임상적 적용)

  • Kwon, Jun-Soo
    • Sleep Medicine and Psychophysiology
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    • v.1 no.1
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    • pp.36-46
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    • 1994
  • The event-related potentials are difined as the changes in voltage that occur at paticular time before, during and after something that happens in the physical world or some psychological processes. The possibilities of clinical applications of ERP are considered because the endogenous potentials such as P3 and contingent negative variation(CNV) are determined by the psychological significance of the stimulus. The P3 is a positive wave that occurs when a subject detects an informative task-relevant stimulus. The P3 amplitude and latency are affected by the various factors as subjective probabilites, stimulus meaning and information transmission. It is suggested that P3 wave is associated with the decision making, cognitive or perceptual closure, memory updating and transfer of information to consciousness etc. Although the intracerebral origin of the P3 wave is not known, the P3 may have multiple intracerebral generators. The CNV is a slow potential shift occuring during the foreperiod, between warning and response signals, in a reaction time experiment. It is related to expectancy, preparation etc. The abnormal findings of P3 wave and CNV in various psychiatric disorders are also discussed.

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A Study of Developing Teaching Material to Improve Creativity with Program Elements (프로그램 요소를 이용한 창의성 신장 교재 개발 연구)

  • Kim, Jong-Hoon;Kim, Jong-Jin;Jeong, Won Hee
    • The Journal of Korean Association of Computer Education
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    • v.8 no.5
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    • pp.17-30
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    • 2005
  • The education has changed from the memory education for knowledge to the creativity education. Education of computer has attached importance to teach the creativity. But it till now developed materials are short improvement of the creativity. Especially studies of computer program education are no more than studies of education for genius. Hereupon I developed the teaching material for elementary students with computer program elements by matters in daily life. It has 20 subject in program elements, the aim is improvement of the creativity. After I taught students with developed teaching material, prove the creativity of students has improved.

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The Development of Textile Design and The Manufacture of Cultural Merchandise by Using Lotus Flower Patterns(II) (연꽃 문양을 이용한 직물디자인 개발 및 문화상품 제작(II))

  • Jung, Jin-Soun
    • Fashion & Textile Research Journal
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    • v.6 no.4
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    • pp.421-426
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    • 2004
  • In an information-oriented and internationalized society of the future, the quality and the price of goods made by each country will be equalized. That eliminates competition. But the design and appearance of products is an important factor in international competition. Indeed, design symbolizes a country's culture visually, and it can show the cultural identity and originality of a nation in international society. And that will play an important part that can contribute to creating added value. It is necessary to revive our people's old lyrical stories which are far away from our memory, and we badly need design development to revive traditional cultural merchandise through visual modernization. In this study, I chose lotus as the subject material of textile design development. And my intention for this study is to reflect Korean traditional cultural value as much as I can, and to develop textile design of Korean images by adding modern scenes. Also, I intend to print them on fabric, and apply them to cultural merchandise including scarves and ties, by using digital textile printing systems. The reasons for doing so, are to create high added value, and to let other peoples of the world, know about our excellent culture.

A Computational Fluid Dynamics Analysis on Sloshing in Rectangular Tank (사각통에서의 슬로싱에 대한 전산유체역학적 연구)

  • Kwack Youngkyun;Lee Youngsin;Kor Sungho
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.99-102
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    • 2002
  • The present study describes a numerical analysis for simulation of the sloshing of flows with free-surface which contained in a rectangular tank The SOLA-VOF (Volume of fluid) method uses a fixed mesh for calculating the motion of flow and the free-surface. This Eulerian approach enables the VOF method to use only a small amount of computer memory for simulating sloshing problems with complicated free-surface contours. The VOF function, representing the volume fraction of a cell occupied by the fluid, is calculated for each cells, which gives the locating of the free-surface filling any some fraction of cells with fluid. Using SOLA-VOF method, the study describes visualization about simulation of the sloshing of flows and damping effect by baffle. Translation and pitching motion of the forms have been investigated The time-dependent changes of free-surface height are used for visualization subject to several conditions such as fluid height horizontal acceleration, sinusoidal motion, and viscosity. The free-surface heights were used for comparing wall-force, which is caused by sloshing of flows. Baffle was Installed to reduce the force on the wall by sloshing of flows. Damping effects was extensively expressed under the conditions such as baffle shape and position.

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An Application of Cognitive Task Analysis for the Evaluation of Human Performance on Inspection Tasks (인지적 작업분석에 의한 검사작업의 인간 수행도 분석)

  • Lee, Sang-Do;Kwack, Hyo-Yean
    • Journal of Korean Society for Quality Management
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    • v.23 no.3
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    • pp.69-83
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    • 1995
  • In a large number of literature on of inspection tasks, one of the most consistent findings is the existence of large and consistent differences among inspectors. It is possible that the individual difference is described by the difference of cognitive skills, because cognitive skills are required more than manual skills in inspection tasks. Therefore, a set of cognitive factors in human information processing may underly human performance in inspection tasks. In this study, a cognitive skill was described as the relative importance of the cognitive factors involved. A hierarchical task analysis and a fuzzy hierarchical analysis were used to represent how the importance of cognitive factors contribute to inspection performance. An experiment was conducted using the computer simulations of PCB inspection tasks. The results revealed that the subject group with better performance showed the importance weights of cognitive factors in the following rank; (attention, perception, judgement, classification, recognition)<(detection)$\ll$(memory). The results of the experiment can serve as a selection criterion for efficient inspection performance and the information of skilled learning for an inspection training program. The usefullness of a hierarchical task analysis and a fuzzy hierarchical task analysis for the analysis of cognitive tasks are also confirmed.

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A study on the effect factor of architectural material expression (재료의 물성 표현에 영향을 주는 요인 연구)

  • Kim, So-Hee
    • Korean Institute of Interior Design Journal
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    • v.15 no.6 s.59
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    • pp.60-67
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    • 2006
  • In modem days when architectural materials have grave impacts on overall design expression, materials for architecture, especially finishing materials have become the most essential elements for the design expression, as architectural space and form have been. When it comes to the architectural materials, they can be conceived by visual and tactile sensory system and perceptional system which based on memory and experience. This study confirms how materials bring into effect on architecture in the sense of its design. The main subject of this analysis is expression method of architectural finishing materials. Also, this study finds out the relationship between finishing materials and the images of materials by analyzing the effect factor of architectural material expression with the perspectives of materials, formal and environments and by examining roles of the architectural materials in design. The material factor, in the expression of materiality, is how to make tectonic space and to vary the surface of building as finishing material design. The formal factor is related to set up the new direction in the architectural form and to create the dynamic and informal space. And the social and cultural environment as the effect factor gives new situation and context to architectural material expression. This principle enables us to use architectural materials as one of the important elements which express the whole characteristics of the area.

A topology optimization method of multiple load cases and constraints based on element independent nodal density

  • Yi, Jijun;Rong, Jianhua;Zeng, Tao;Huang, X.
    • Structural Engineering and Mechanics
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    • v.45 no.6
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    • pp.759-777
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    • 2013
  • In this paper, a topology optimization method based on the element independent nodal density (EIND) is developed for continuum solids with multiple load cases and multiple constraints. The optimization problem is formulated ad minimizing the volume subject to displacement constraints. Nodal densities of the finite element mesh are used a the design variable. The nodal densities are interpolated into any point in the design domain by the Shepard interpolation scheme and the Heaviside function. Without using additional constraints (such ad the filtering technique), mesh-independent, checkerboard-free, distinct optimal topology can be obtained. Adopting the rational approximation for material properties (RAMP), the topology optimization procedure is implemented using a solid isotropic material with penalization (SIMP) method and a dual programming optimization algorithm. The computational efficiency is greatly improved by multithread parallel computing with OpenMP to run parallel programs for the shared-memory model of parallel computation. Finally, several examples are presented to demonstrate the effectiveness of the developed techniques.

The Effects of Walking and Yoga Exercise on the Cognitive Functions in the Elderly Women (걷기와 요가가 포함된 복합운동이 여성노인의 인지기능에 미치는 영향)

  • Kim, Yong-Geon;Han, Dong-Wook;Lee, Byoung-Kwon
    • Journal of the Korean Society of Physical Medicine
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    • v.5 no.2
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    • pp.211-221
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    • 2010
  • Purpose : The purpose of this study is to find out the effects of combined exercise including walking and yoga on cognitive functions in the elderly women. Methods : Sixteen elderly women aged above 65 are invited in this study. Each subject participated in exercise three times a week for eight weeks from July 14th to September 13th in 2008. The changes between pre and post exercise are analyzed by Wilcoxon sign rank test and repeated ANOVA test with SPSS (ver 17.0) package program. Results : After exercise, In the below 23 points group, only interference STROOP test (p<.05) among sub items of Cognition Scale for Older Adults (CSOA) is improved significantly. In the above 24 points group, words memory (p<.05), delayed recall (p<.05), and picture naming (p<.05) among sub items of CSOA are improved significantly. But it is no different to the change patterns among two groups. Conclusion : These results show that combined exercise including walking and yoga is helpful to improve cognitive functions. And we find that exercise is helpful in the above 24 points elderly women more than in the below 23 points.

The Road to Empire: Journeys to Europe and Far Eastern Asia by Natsume Soseki ('제국'으로 가는 길 - 나쓰메 소세키의 유럽과 아시아 여행)

  • YOON, Sang-In
    • Cross-Cultural Studies
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    • v.33
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    • pp.263-286
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    • 2013
  • Is this a right way in politics that attitude of Japanese scholars to separate Natsume Soseki from the expansionism of pre-war Japan to protect 'sanctity'? Nowadays, most Japanese scholars are regarded to share the desire that minimize the memory of the behavior of Japanese Imperialism in East Asia, such as Korea, China, etc. Furthermore, 'the desire to minimize' inescapably concluded in avoidance, concealment, at last the temptation of deliberate misleading. Until now, the controversy about the Natsume Soseki's travel to Korea and Manchuria has repeated in defence and criticism surrounding the self-awareness and recognition of others of Natsume Soseki, making the expression in a record of Natsume's travel as the subject of study, for example, the degrading expression about Chosun people and scorn for Chinese and Russian. This paper will investigate that Natsume's travel is the political practice which is combined with the desire for the empire, focusing on the political context in the action of journey of Natsume and its contents other than the expression itself.