• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.4
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• pp.44-52
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• 2003

Shape memory alloys (SMA) are often used in smart structures as active components. Their ability to provide large recovery forces and displacements has been useful in many applications, including devices for artificial muscles, active structural acoustic control, and shape control. Based on the 3-dimensional SMA constitutive equation in this paper, the radial displacement control of externally pressurized circular and semicircular composite cylinders under external pressure with a thin SMA layer bonded on its inner surface or inserted between composite layers in investigated using 3-dimensional finite element analysis. Upon actuation through resistive heating, SMAs start to transform from martensitic into austenitic state, simultaneously recover the prestrain, and thus cause the composite cylinders to go back to their original shapes of the cylinder cross-sections.

• Korean Journal of Cognitive Science
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• v.22 no.2
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• pp.193-215
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• 2011

The purpose of this study was to examine the working memory that is related with reading. For this purpose, the third and fourth grade children with reading difficulty were compared with normal children. The gender comparison and the correlations among the three components of working memory were also examined. The results indicated that the reading difficulty group were outperformed by the normal group in every test. Gender difference was found only in visuospatial capacity. There was an interaction between reading and gender in the memory of dynamic mazes. In the whole group, every correlation among all components was significant. When the correlations were examined separately in each group, however, only one correlation was significant in both groups. When the influence of the central executive was controlled, the interrelationship between phonological working memory and visuospatial working memory was mitigated. This study suggests that when teaching children with reading difficulty instructional material should be succinct and visuospatial information needs to be used for boys if possible.

• Science of Emotion and Sensibility
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• v.15 no.4
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• pp.477-488
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• 2012

The effort of implementing realistic 3-D depth on 2-D images has been continued persistently with a theoretical understanding of depth perception and its related technical development. The present article briefly reviews a number of popular stereoscopes for studying stereoscopic depth perception according to their implementation principles, and introduces a behavioral experiment as a technical example in which the active-shutter glasses were used. In the present study, participants were tested for their visual memory against perceived depth among a set of items. The depth of the memory and test items was manipulated to be 1) monocular, 2) binocular, or 3) both-monocular-and-binocular respectively. The memory performance was worst in the binocular-depth condition, and best however in the both-monocular-and-binocular condition. These results indicate that visual memory may benefit more from monocular depth than stereoscopic depth, and further suggest that the storage of depth information into visual memory would require both binocular and monocular information for its optimal memory performance.

• The Journal of the Korea Contents Association
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• v.15 no.4
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• pp.545-555
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• 2015

We investigated the influence of negative emotion such as state-trait anxiety and depression and working memory (WM) on Foreign Language Vocabulary Learning (FLVL) of South Korean university students. Also, its implications for developing contents for FLVL were discerned. To do so, state-trait anxiety and depression inventories as well as four kinds of WM test were performed for 132 undergraduate students. Participants also had two semantic learning sessions for Swahili words. The mean scores of negative emotions were normal level. The results of structural equation modeling (SEM) showed that there was no effect of negative emotion on FLVL, while direct effects of the negative emotion on WM and the WM on FLVL were significant. Such results suggested that FLVL would be weakened, with the result that WM had been impaired by negative emotions. These outcomes suggested that when developing FLVL content for university students, it is necessary to consider the negative emotions of foreign language learners and to develop the contents for FLVL in the light of WM load.

• Korean Journal of Cognitive Science
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• v.7 no.3
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• pp.37-60
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• 1996

From the biopsychological point of view,learning could be defined as the processes to transfer the information that we obtain from environment to the neural circuits in the brain.In the studies to determine the biological substrates of learning and memory,there was a remarkable effort to identify neural circuits related with a specific type of learning and to describe the mechanixm of neural plasticity of learning and memory,under the assumption that the memory orinformation may be stored as a modificationof neural synapes in the central nerviys system.On the other hand,there was a different kind of tendency to analyze the mechanism of interactions between neural substrates involved in learning and memory,under the assumption that a specific information may be represented in the patterns of comples neural network of the central nervous system.The present review,in the former position.focused on the research methods and the chracteristics and finding of the investigations employing animal model systems to indentify the essential site of engram for learning and memory.Specifically,the review presents major advances in ourunderstanding of the memory trace circuit for a specific type of learning,with the use of animal model system,the detemination of the critical lodi of neuaral plastic chabges In learing abd memory,and the neurophysiological an biocemical mechanixms of the neural modifia by learint.

• The KIPS Transactions:PartD
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• v.18D no.1
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• pp.1-8
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• 2011

The cache structure, which is designed for assuring fast accesses to frequently accessed data, resides on the various levels of computer system hierarchies. Many studies on this cache structure have been conducted and thus many page-replacement algorithms have been proposed. Most of page-replacement algorithms are designed on the basis of heuristic methods by using their own criteria such as how recently pages are accessed and how often they are accessed. This data-retrieval process in computer systems is analogous to human memory retrieval process since the retrieval process of human memory depends on frequency and recency of the retrieval events as well. A recent study regarding human memory cognition revealed that the possibility of the retrieval success and the retrieval latency have a strong correlation with the frequency and recency of the previous retrieval events. In this paper, we propose a novel page-replacement algorithm by utilizing the knowledge from the recent research regarding human memory cognition. Through a set of experiments, we demonstrated that our new method presents better hit-ratio than the LRFU algorithm which has been known as the best performing page-replacement algorithm for DBMS caches.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.8
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• pp.1083-1089
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• 2010

Shape memory alloys (SMAs) are smart materials. The unique characteristics of SMAs enable the production of large force and displacement. Hence, SMAs can be used in many applications such as in actuators and active structural acoustic controllers; the SMAs can also be used for dynamic tuning and shape control. A SMA torque tube actuator consisting of SMA tubes and superelastic springs is proposed, and the behaviors of the actuator are investigated. From the results of heat transfer analysis, it is proved that the SMA torque tube actuator with both resistive heating of SMA itself and a separate conventional heating rod in the tube core has good performance. The behavior of an actuator system was analyzed by performing a contact analysis, and the twisting motion was noticed when checking the actuation. 3D SMA nonlinear constitutive equations were formulated numerically and implemented by performing a nonlinear analysis by using Abaqus UMAT.

• Archives of design research
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• v.15 no.1
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• pp.27-36
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• 2002

To do this, study of human memory and theoretical approach on form in general is carried out to compare the types of memories and the stage of perceive theoretically to discover the relationship between psychological perceive and form. In the second please, scenario of form recognition in cultural aspect is studied through various written records to obtain unbiased critics on what a person can feel from a form through various analysis and experiment. Examples will be given on products designed on the basis of correlation with form through analysis. Through this procedure, elements of reactions on implicit and explicit is derived (Data obtained from experiments on computers and inquiries are used) Analyzed elements are than divided into, general knowledge, memories of reality and subconsciousness memories and basic mental image and user mental image and mental image of form of each products are analyzed. In the third phase, the way of adapting of the elements obtained from the analysis of implicit and explicit reaction to the field of design is predicted. Together with this, future theme this the study will be suggested. Confusions obtained from this study can be listed as below.

• Science of Emotion and Sensibility
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• v.21 no.1
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• pp.129-142
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• 2018

We spend about one-third of our life sleeping. Although the influence of sleep on various cognitive and affective functioning is recognized, relatively less is known about its consequences on interpersonal relationships. The present study examines whether sleep contributes to adolescent's peer intimacy; specifically, given the role of sleep in memory consolidation, it was assumed that a good sleep will enhance social relationships by positively refurbishing memories of social episodes. As predicted, young teenagers' sleep quality predicted increased peer intimacy, partly through the positive memory of social events, in a sample of middle school (Study 1) as well as high school participants (Study 2). To investigate the causal link, in Study 2, memory recollections were repeatedly measured for a week. Sleep quality during the week predicted how social, but not non-social episodes were positively remembered. The function and importance of sleep quality are discussed in the context of interpersonal relationships.

• Journal of the Korean Geographical Society
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• v.48 no.3
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• pp.433-452
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• 2013

Bonjeong-tong(本町通) which was originated from Japanese place name and commercial center during Japanese colonial period speaks for downtown in the urban Korea of today. This study tries to investigate a variety of place memories that have been layered in Bonjeong-tong in the case of Chungmu-ro and Myeongdong area in Seoul, Korea. The author settles the concept of 'place memory' from the viewpoint of the discipline of human geography, and reconstructs place memories of Bonjeong-tong by three folds of layers focusing on the multilayeredness and the contestedness of place memories which have been piled up in Bonjeong-tong; 'the symbol of colonial power' vs. 'the emblem of modernization', 'the heart of monetary capitalism' vs. 'the ground of humanists and artists', 'the space of fashion' vs. 'the place of identity'. As a result, the author places emphasis on that a place like Bonjeong-tong in itself within a city is a sort of palimpsest, and suggests that therefore it is necessary to adopt a vertical approach not a horizontal one for the study on urban space in future.