• Electrical & Electronic Materials
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• v.6 no.2
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• pp.152-160
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• 1993

MNOS 구조에서 23.angs.의 얇은 산화막을 성장한 후 LPCVD방법으로 S $i_{3}$ $N_{4}$막을 각각 530.angs., 1000.angs. 두께로 달리 증착했을때 비휘발성 기억동작에 미치는 전하주입 및 기억유지 특성을 자동 .DELTA. $V_{FB}$ 측정 시스템을 제작하여 측정하였다. 전하주입 측정은 펄스전압 인가전의 초기 플랫밴드전압 0V.+-.10mV, 펄스폭 100ms 이내로 설정하고 단일 펄스전압을 인가하였다. 기억유지특성은 기억트랩에 전하를 포획시킨 직후 $V_{FB}$ 유지와 0V로 유지한 상태에서 $10^{4}$sec까지 측정하였다. 본 논문에서 유도된 산화막 전계에 대한 터넬확률을 적용한 전하주입 이론식은 실험결과와 잘 일치하였으며 본 해석방법으로 직접기억트랩밀도와 이탈진도수를 동시에 평가할 수 있었다. 기억트랩의 포획전하는 실리콘쪽으로의 역 터넬링으로 인한 조기감쇠가 컸으며 $V_{FB}$ 유지인 상태가 초기 감쇠율이 0V로 유지한 경우 보다 낮았다. 그리고 기억유지특성은 S $i_{3}$ $N_{4}$막의 두께보다 기억트랩밀도의 의존성이 크며 S $i_{3}$ $N_{4}$막두께의 축소로 기록전압을 저전압화시킬 수 있음을 알 수 있었다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.11a
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• pp.453-456
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• 2009

Impact resistance of shape memory alloy hybrid composite(SMAHC) plates were experimentally investigated. Shape memory alloy(SMA) have large failure strain and failure stress and can absorb large strain energies through phase transformation. SMA wires were embedded in composite plates to improve their weak impact resistance. Tensile tests of SMA wires were performed at various temperature to investigate their thermo-mechanical properties. Low-Velocity impact tests of several types of composite plates with SMA/Al/Fe were performed. Embedding SMA wires was most effective to improve impact resistance of composite plates. The effects of SMA position on impact resistance were also investigated.

• Science of Emotion and Sensibility
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• v.5 no.1
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• pp.79-90
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• 2002

The role of memory is viewed as central to developing and maintaining flight situation awareness (SA). The present research examines constituent memory processes that underlie flight SA sensitivity as a function of pilot expertise. In Experiment 1, pilot memory for different forms (spatial or verbal) of cockpit situational information was tested immediately after presentation of the information (immediate recall) or after 30-s delay filled with an intervening task (delayed recall). In Experiment 2, pilot SA sensitivity was examined and correlated with memory measures obtained in Experiment 1. Results suggest that an expertise effect occurs in delayed recall but not in immediate recall and that memory representation of situational information required to develop high levels of SA sensitivity varies as a function of expertise. Theoretical accounts of results are discussed in the context of psychological theories of expertise.

• Korean Journal of Cognitive Science
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• v.22 no.2
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• pp.145-172
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• 2011

Prospective memory (PM) is memory for activities to be performed in the future, such as remembering to purchase a piece of fruit on the way home or remembering to give someone a telephone message. Theoretically, PM retrieval can be accomplished either by controlled monitoring of intended action or by a more automatic process that spontaneously responds to the presence of intended event. The present study examined the effect of meta-cognitive awareness in PM retrieval process. In Experiment 1, we manipulated PM condition with a salient cue to stimulate participants' meta-cognitive awareness. Results showed the salient cue condition spontaneously triggered remembering to perform an intended action. In Experiment 2, we manipulated participants' meta-cognitive awareness about PM task difficulty and about the degree to which cognitive capacity is required to realize the PM task. Results showed that PM retrieval process varied with meta-cognitive awareness (i.e., more resources were allocated if the PM task was expected to be difficult). These results imply that participants' meta-cognitive awareness play an important role in PM retrieval process.

• Science of Emotion and Sensibility
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• v.15 no.4
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• pp.527-540
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• 2012

We examined the effect of delayed and immediate rewards on short- and long-term memory performance depending on the level of stress. It has been demonstrated that delaying feedback during memory tasks could lead to better retention than presenting it immediately (a.k.a., feedback delay benefit or delay-retention effect). In this study, we manipulated stress level(high-stress or low-stress), reward-timing(delayed or immediate reward), reward-existence(500 or 0 won) and retrieval-timing(delayed or immediate memory test). On the high-stress learning condition, one week later, the number of correct answers with delayed-rewards were significantly more than that of delayed-no-rewards but there was not any difference between immediate-rewards and immediate-no-rewards. On the other hand, in the high-stressful immediate memory test, immediate-rewards only had a positive effect on memory performance. The results indicated that delayed rewards improved long-term memory performance by promoting memory consolidation and the sensitivity to rewards was higher under the high-stress condition.

• Korean Journal of Cognitive Science
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• v.23 no.4
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• pp.425-455
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• 2012

Multi-dimensional verbal short-term memory mechanisms are largely divided into the phonological channel and the lexical-semantic channel. The former is called phonological short-term memory and the latter is called semantic short-term memory. Phonological short-term memory is further segmented into the phonological input buffer and the phonological output buffer. In this study, the language performance of each of three patients with similar levels of conduction aphasia was analyzed in terms of multi-dimensional verbal short-term memory. To this end, three patients with conduction aphasia were instructed to perform four different aspects of language tasks that are spontaneous speaking, repetition, spontaneous writing, and dictation in both word and sentence level. Moreover, the patients' phonological memories and semantic short-term memories were evaluated using digit span tests and verbal learning tests. As a result, the three subjects exhibited various types of performances and error responses in the four aspects of language tests, and the short-term memory tests also did not produce identical results. The language performance of three patients with conduction aphasia can be explained according to whether the defects occurred in the semantic short-term memory, phonological input buffer and/or phonological output buffer. In this study, the relations between language and multi-dimensional verbal short-term memory were discussed based on the results of language tests and short-term memory tests in patients with conduction aphasia.

• Korean journal of communication and information
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• v.81
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• pp.299-328
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• 2017

This study investigated news comprehension via the social media by comparing the reading of a news story on the news paper. A news story on the social media was suggested to present information in a conversational form, which differs from a traditional reporting style. To compare the different forms of news information presentation, two conditions were created: in a control condition, a news story was written in a traditional reporting form. In the experimental condition, the same news story was constructed in a conversational form. Participants were assigned randomly in one of two conditions. They read the news story and afterwards, they were asked to recall firstly, the core idea of the news story, secondly the whole news story, and finally to answer to the 10 questions that assessed how well they learned from the news story. Participants' responses were content-analyzed and produced six variables, the extent to recall the core idea, the extent to recall the whole story, the extent to recall wrong information, the extent to recall additional information, the extent to recall causally related contents in general, and finally the extent to recall causally related contents in story-specific. Analyses on the six variables revealed that the group in the news paper condition recalled more core idea, the whole story, and additional information than the group in the social media. But the news paper condition recalled less of wrong information than the group in the social media condition. Additionally, the news paper condition learned more than the group in the social media. Regarding the recall of causally related contents, the general causal relationships were recalled more in the group in the social media condition but the story specific causal relationships were recalled more in the group in the news paper condition. The findings seemingly indicated that a traditional news reporting contributes to news story comprehension more than the conversational form. Authors however added discussions and advised that the findings needed to be read under caution.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.23 no.2
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• pp.45-68
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• 2012

Archives have directly and indirectly served for memory. What is collected in archives, how it is presented to users, and how users understand and use the documents affects how a given society remembers its past. Some archival scholars see that how users interpret documents from their perspectives and by social interests may play a central role in constructing social memory because memories are often triggered by individual and social concerns of the present time. Therefore, knowing what causes users to seek for a certain materials, how they use those materials and why can offer a clue to learn how archives serve for social memory. In the Web space, the interaction between users and archives/archival materials can be easily observed. Beyond making access simple for users and promoting archival documents using Web technology, archives can serve the broader purpose of memory by skillfully exploiting the characteristics of Web 2.0 and digital cultures in a way to observe how users engage in and contribute to archival contents available on the Web. This study examines the discourses on memory in the archival context, and in particular, how archives can serve as platforms for memory within the new environment of Web 2.0 technologies. It surveys discussions on memory in relation to archives, history, and evidence, focusing on the user and use context as it is represented in the archival literature. This paper discusses how that technology provides features that allow us to see collective memory being constructed in the archives, and presents examples of how the Web 2.0 technology can structure the way users share their memories in building a larger narrative around the archive.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2001.12a
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• pp.208-212
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• 2001

This paper is for the optimized management of the knowledge abstracted from the World-Wide Web(WWW) in which we assume the infinite knowledge-base. Though we can abstract various useful knowledge such as the facts and the rules from the WWW pages, they may include many noisy knowledge. Therefore we have to reasonably reject them from the knowledge-base which is composed of knowledge abstracted from the WWW. To do this, we propose the oblivious memorization concept. This concept is characterized by the memorization based on the oblivion mechanism of human being. We assume the memorization is the function of the concern for any knowledge, oblivion ability and time. That is, the more concern for my knowledge the ore memorizable. And, the more oblivious and the more tine spent the less memorizable by exponentially. Where, tie assume the oblivion is the function of the degree of previous memorization, memorization ability md the number of knowledge stimulation. That is, the more previously memorized, the greater memorizing ability and the more frequently stimulated by any knowledge the less knowledge oblivious.

• Composites Research
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• v.17 no.5
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• pp.54-60
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• 2004

A new three-dimensional model for predicting the relationship between the prestrain of the composite and the amount of phase transformation of shape memory alloy inducing shape memory effect has been proposed by using Eshelby's equivalent inclusion method with Mori-Tanaka's mean field theory. The model composite is aluminum matrix reinforced with short TiNi fiber shape memory alloy, where the matrix is work-hardening material of power-law type. The analytical results predicted by the current model show that most of the prestrain is induced by the plastic deformation of the matrix, except the small prestrain region. The strengthening mechanism of the composite by the shape memory effect should be explained by excluding its increase of yield stress due to the work-hardening effect of the matrix.