• Environmental and Resource Economics Review
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• v.19 no.3
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• pp.485-508
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• 2010

This paper examines the long memory property and investigates cointegration in the dynamics of crude oil markets. For these purposes, we apply the joint ARMA-FIAPARCH model with structural break and the vector error correction model (VECM) to three daily crude oil prices: Brent, Dubai and West Texas Intermediate (WTI). In all crude oil markets, the property of long memory exists in their volatility, and the ARMA-FIAPARCH model adequately captures this long memory property. In addition, the results of the cointegration test and VECM estimation indicate a bi-directional relationship between returns and the conditional variance of crude oil prices. This finding implies that the dynamics of returns affect volatility, and vice versa. These findings can be utilized for improving the understanding of the dynamics of crude oil prices and forecasting market risk for buyers and sellers in crude oil markets.

• Journal of the Korea Convergence Society
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• v.9 no.2
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• pp.171-176
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• 2018

The purpose of this study is to establish smart signage in a certain space and to analyze not only media ingestion and advertising inducement as well as any information (high vs. low vs. low) and flow level And the memory effect related to whether or not to remember. The results of this study show that the higher the interaction level and the higher the engagement level, the higher the advertising engagement is. In addition, media involvement was high when interaction level was low and flow level was high. Finally, if the level of interactivity is low and the level of flow is high, then non - valued attribution information is more likely to be recalled than the comprehensive evaluation information. If the interaction of smart signage is high and the flow of users is low, Recalled more recall information. In the future, detailed strategies for enhancing user flow will be needed rather than a strategy for unconditional enhancement of interaction in smart signage strategy.

• Journal of the Korean Geographical Society
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• v.44 no.6
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• pp.779-796
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• 2009

Pimat-gil is a bystreet over 600-years old of Jong-no in Seoul that originated in the early Joseon Dynasty. This Study defines Pimat-gol (a street village) that has developed centering around Pimat-gil (alley) as a typical backlane of modern city, traces the origin and landscapes of Pimat-gol through the historical geographies of this place, and tries to name and interpret the placeness of Pimat-gol from the angles of social and cultural geography, particularly on the basis of the concept 'place memory'. As a result, the author extracts the placeness of Pimat-gol in terms of juxtaposition of three-fold layers, ie., 'space of subaltern vs. space of escape', 'space of oblivion vs. space of recollecttion and generation', and 'space of fossil vs. space of living'. In addition, the author examines the place memories which have been sedimented in this place and the contest of the place-memories by investigating these three-fold layers, and makes a proposal which would constructs another spatiality of modern city on the basis of this case.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.209-209
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• 2010

단위면적 당 메모리 집적도를 높이기 위해 플래시 기억소자의 크기를 줄일 때, 절연층 두께 감소에 의한 누설 전류의 발생, 단채널 효과 및 협폭 효과와 같은 문제 때문에 소자 크기의 축소가 한계에 도달하고 있다. 이러한 문제점들을 개선하기 위해 본 연구에서는 FinFET구조위에 Oxide-Nitride-Oxide (ONO) 층을 적층하여 2-비트 특성을 갖는 플래시 메모리 소자를 제안하였다. 소자의 작동전압을 크게 줄일 수 있으며 소자의 크기가 작아질 때 일어나는 단채널 효과의 문제점을 해결할 수 있는 FinFET 구조를 가진 기억소자에서 제어게이트를 제어게이트1과 제어게이트2로 나누어 독립적으로 쓰기 및 소거 동작하도록 하였다. 2-비트 동작을 위해 제어 게이트1의 게이트 절연막의 두께를 제어게이트2의 게이트 절연막의 두께보다 더 얇게 함으로써 두 제어게이트 사이의 coupling ratio를 다르게 하였다. 제어게이트1의 트랩층의 두께를 제어게이트2의 트랩층의 두께보다 크게 하여 제어게이트1의 트랩층에 더 많은 양의 전하가 포획될 수 있도록 하였다. 제안한 기억소자가 2-비트 동작하는 것을 확인 하기위하여 2차원 시뮬레이션툴인 MEDICI를 사용하여 제시한 FinFET 구조를 가진 기억소자의 전기적 특성을 시뮬레이션하였다. 시뮬레이션을 통해 얻은 2-비트에 대한 각 상태에서 각 전하 포획 층에 포획된 전하량의 비교를 통해서 coupling ratio 차이와 전하 포획층의 두께 차이로 인해 포획되는 전하량이 달라졌다. 각 상태에서 제어게이트에 읽기 전압을 인가하여 전류-전압 특성 곡선을 얻었으며, 각 상태에서의 문턱전압들이 잘 구분됨을 확인함으로써 제안한 FinFET 구조를 가진 플래시 메모리 소자가 셀 당 2-비트 동작됨을 알 수 있었다.

• Journal of the Korean Society for Nondestructive Testing
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• v.22 no.1
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• pp.45-52
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• 2002

It has been known that tensile residual stresses occurring by the thermal expansion coefficient mismatch between fiber and matrix is a cause of the weak strength of metal matrix composites(MMCs). In order to solve this problem, TiNi alloy fiber was used as a reinforced material in TiNi/A16001 shape memory alloy composite in this study. TiNi alloy fiber improves the tensile strength of the composite by causing compressive residual stress in matrix on the basis of its shape memory effect. Pre-strain was imposed to generate the compressive residual stresses inside the TiNi/A16001 shape memory alloy composites. AE technique was used to quantify the microscopic damage behavior of the composite at high temperature. The effect of applied pre-strains on the AE behavior was also evaluated.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.10
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• pp.1835-1844
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• 2007

Recently there have been some positive evidences on the effects of learning in a virtual environment. However, most of these educational VR systems were not deeply considered in the design of drawing a learner's attention on lesson contents, which would help enhance retained memory. Hence, a study was conducted to measure 17 subjects' attention states using EEC, ECG, GSR, and eye-tracking and their behaviors while they were given guided search task or exploration task in a virtual environment consisting of five major events. It also analyzed the subject's remembered items after their VR experiences using a surrey. This paper Int describes an overview of the ocean virtual environment used in this study, and it then explains the experimental design, apparatus, and method. It will also discuss the results by a detail analysis (in a whole VR session as well as event-related 10-second 33 sub-sessions) with the subjects' attention states and their retained memory after the learning.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.283-292
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• 2019

The loss of semantic knowledge and impairments in semantic associations by semantic category is gaining increasing attention, as indicators of early-stage cognitive decline. As such, we assigned semantic association task (SAT) to normal elderly (NE) and those with subjective memory impairment (SMI) or mild cognitive impairment (MCI) to examine their performance by semantic subcategories and the differences in error patterns. We found a significant difference in the number of correct response and reaction time under the SAT categories among the three groups, with the highest performance observed in 'function' and the lowest performance in 'superordinate' and 'part/whole'. Moreover, the error frequency was the lowest in NE, followed by those with SMI and MCI, with the latter two groups showing a significant increase in no-response. Our findings demonstrate the varying extent and process of impairments in the semantic network by category over different stages of cognitive decline. Thus, we proposed SAT performance as an indicator to detect and follow-up on cognitive decline in elderly with cognitive disorder.

• Journal of the Economic Geographical Society of Korea
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• v.21 no.4
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• pp.393-408
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• 2018

This study aims to raise our understanding of how memory of a social group is transnationally appropriated and utilized by other subjects. A collective sense of justice for comfort women has been handed to many Koreans either in Korea or in overseas countries since the early 1990s. In the U.S., the first comfort women monument was established in Palisades Park, New Jersey by Korean-Americans and local politicians as they wanted to strengthen the common sense of Korean ethnicity with the symbolic power of the memoryscape. Exploring the diffusion of comfort women memorials in the U.S., this study examines the complexity and multilayered structure of memory politics and its transnational mobility, which are connected to Korean-Americans' struggle for belonging.

• The Journal of the Korea Contents Association
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• v.19 no.9
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• pp.101-111
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• 2019

This study was to examine association between working memory and social cognitive ability, and the influence of story-use on social cognitive ability. To this end, this study measured working memory(via n-back), and randomly assigned 82 participants into three groups(5th level intentionality, 3rd-level intentionality, and exposition conditions), and then compared the accuracy of perspective taking and emotion recognition(RMET: Reading Minds in the Eyes Test) as social cognitive ability. The results suggested that perspective taking accuracy was significantly associated with working memory capacity, whereas emotion recognition accuracy was not. Contrary to the hypothesis, perspective taking in the 5th-level intentionality story group were significantly lower than those in the 3rd-level intentionality story group. Emotions recognition accuracy was not significantly different among the three groups. Overall, this study produced inconsistent results, which has been discussed in terms of theory and methods.

• The Korean Journal of Archival Studies
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• no.39
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• pp.73-100
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• 2014

For a society to be constantly sustained, it needs its past memories to be made present into cultural memories. The state of oblivion resulted from the time difference of the past and the present is commonly made present into commemoration days or memorial spaces. Each has its own form of representation it reflects, but all are related to how past is remembered and how it will be formed. Records, especially the authentic records the nation secured, have an ontological feature of proof that is able to persuade the current present of the past present, and inherent in it is faith that originates from fundamental objectivity. Therefore the image of silence that such strictness of records creates realizes the detonation of specific memories through the act of visual exhibition. Hence, this paper endeavors to examine how the national records, particularly the photographical records, was utilized and how it influenced the people and the society after its organization, through analysing examples of memorial spaces.