• Korean Journal of Pharmacognosy
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• v.41 no.3
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• pp.196-203
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• 2010

Black sesame (Sesami semen nigrum) has been used to treat dizziness, earnoise, constipation in the traditional Chinese medicine. In the present study, we assessed memory enhancing properties of 70% ethanolic extract of black sesame (EBS70) and its ameliorating activities on learning and memory impairments induced by scopolamine. Drug-induced amnesia was made by scopolamine treatment (1 mg/kg, i.p.). Single EBS70 (200 mg/kg, p.o.) administration significantly enhanced cognitive function and attenuated scopolamine-induced cognitive impairments as determined by the passive avoidance and Y-maze tasks (P<0.05) and also reduced escape-latency on the Morris water maze task (P<0.05). In addition, EBS70 increased BDNF expression in hippocampus 4 h after its administration (P<0.05). These results suggest that EBS70 enhances learning and memory in normal state and attenuates amnesic state caused by cholinergic dysfunction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4446-4462
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• 2019

In this paper, we focus on interference cancellation for three-hop cognitive radio networks (CRNs) over Rayleigh fading channels. In CRNs, secondary users (SUs) are allowed to opportunistically utilize the licensed spectrum during the idle time of primary users (PUs) to achieve spectrum sharing. However, the SUs maybe power constrained to avoid interference and cover a very short transmission range. We here propose an interference cancellation scheme (ICS) for three-hop CRNs to prolong the transmission range of SUs and improve their transmission efficiency. In the proposed scheme, a flexible transmission protocol is adopted to cancel the interference at both secondary relays and destinations at the same time. And a closed-form expression for the secondary outage probability over Rayleigh fading channels is derived to measure the system performance. Simulation results show that the proposed scheme can significantly reduce the secondary outage probability and increase the secondary diversity in comparison with the traditional cases.

• Proceedings of the Korean Society of Sericultural Science Conference
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• 2005.04a
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• pp.41-41
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• 2005

• Proceedings of the Korean Society for Cognitive Science Conference
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• 2006.06a
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• pp.29-32
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• 2006

이 연구에서는 표적과 방해자극을 분리시킬 때 관찰되는 간섭 감소가 반구내 및 반구간 조건에서 달리 나타난다는 것을 보여주기 위해 세 개의 실험을 실시하였다. 세 실험의 과제는 모두 색깔이 있는 원과 사각형이 주어지고 항상 검은색으로 제시되는 색 이름 단어가 주어진 상황에서 원의 색은 무시하고 사각형의 색과 단어가 의미하는 색이 같은지, 다른지를 판단하는 것이었다. 사각형의 색이 단어가 의미하는 색과 일치할 때 방해자극인 원의 색도 단어가 의미하는 색과 일치하는지 여부에 따라 방해자극의 세 조건(일치, 불일치, 중립)이 만들어졌다. 또한, 방해자극인 원이 표적 가운데 하나인 단어와 같은 시각장에 제시되는지, 혹은 반대편 시각장에 따로 제시되는지에 따라 반구 간섭조건(반구내 간섭, 반구간 간섭)이 만들어졌다 간섭효과는 불일치 조건과 중립 조건간의 차이로 측정하였다. 실험 1의 결과는 정확률과 반응시간 모두에서 반구내 간섭이 반구간 간섭보다 유의미하게 더 큰 것으로 나타났다. 실험 2에서는 방해자극인 원을 선제시하였는데 그 결과 반구내 간섭이 특히 크게 감소하여 반구내 간섭과 반구간 간섭이 차이를 보이지 않게 되었다. 그러나 표적자극인 사각형을 선제시한 실험 3에서는 반구내 간섭이 여전히 반구간 간섭보다 유의미하게 큰 것으로 나타났다. 세 실험의 결과를 종합하면 방해자극의 간섭 효과는 방해자극을 표적과 다른 반구로 분리 제시하거나, 선제시 같은 방법으로 방해자극을 표적과 분리시킬 때 유의미하게 감소하였다. 그러나 애초부터 방해자극을 표적과 다른 반구로 분리 제시하였던 반구간 간섭조건에서는 방해자극의 선제시가 간섭 감소를 가져오지 않았다. 지질의 산패를 가속화시킨 결과라고 생각된다. 따라서 호박 라면 제조시 이러한 공기와의 접촉을 차단시킬 수 있는 포장재료를 선택해야 될 것으로 사료된다.0.05), 맛, 연도, 다즙성 및 전체적인 기호성은 유의한 차이가 없었다.자체를 악하다고 볼 수 없고 더구나 구원을 이 세상에서의 이탈로 볼 수 없다. 진정한 구원이란 원래 하나님이 보시기에 아름다웠던 그 세상으로의 회복을 포함한다. 이런 면에서 하나님 주권 신앙 하에서 구원이란 전 인격적인 구원, 전 우주적인 구원이 된다. 그렇기 때문에 성도는 세상의 삶과 학문, 예술, 정치, 경제, 사회를 포함한 모든 분야를 하나님의 뜻 가운데서 그 원래의 목적에 부합할 수 있도록 회복시키는 일에 적극 참여해야 한다.자체가 이를 주도하기는 사실 어려움이 있다. 그리고 대형유통점이 영업행위를 영업시간제한에서부터 출점제한에 이르기까지 규제하는 건은 심사숙고하여야 한다. 대형유통점이 국가경제 및 지역사회에 미치는 영향이 부정적인가 긍정적인가에 대해 국내외 학계와 업계에서 여전히 많은 논란이 있기 때문이다. 정부와 지자체에 의한 시장개입은 반드시 필요한 경우에 한해 합당한 방법에 의해 이루어져야 한다. 대형유통점에 대한 규제는 지역사회에 미치는 영향을 다면적으로 평가한 결과에 근거하여 이루어져야 할 것이다. 대부분의 지자체는 체계적인 평가시스템과 객관적인 통계 자료를 갖고 있지 못한 실정이다. 향후 가장 시급한 과제는 시장개방 이후 지난 10년간 대형유통점이 지역사회에 미친 영향에 관한 광범위한 통계자료를 수집하고 이를 체계적으로 분석하여 정책방향을 올바르게 설정하는 것이라 할 수 있다.i와 K. pneumonia

• Journal of Life Science
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• v.22 no.5
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• pp.613-620
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• 2012

To evaluate the effects of sleep habits on the powers of beta waves and the sensory motor rhythm of the electroencephalogram (EEG), female college student subjects were divided into four groups, according to their sleep habits, as follows: GSHG (Good Sleep Habit Group), CSHG (Common Sleep Habit Group: late bedtime), CSDG (Cognitive Sleep Disorder-Delayed Sleep Phase Syndrome Group), and NSDG (Non-cognitive Sleep Disorder-Delayed Sleep Phase Syndrome Group). Brain function was stimulated by reading a book for 3 min in the morning (9~12 am) and the EEG was measured. According to the results, the powers of the beta waves and sensory motor rhythm were not different during the resting period among the four groups. However, during the reading stimulation period, the powers of beta waves and the sensory motor rhythm in the GSHG were significantly greater than in the other groups ($p$ <0.05). Beta powers during stimulation also increased in all brain areas in the GSHG ($p$ <0.05). Interestingly, these were decreased in the frontal and temporal lobes in the CSHG by the reading stimulation ($p$ <0.05). On the other hand, sensory motor rhythm, which represents focusing efficacy, only improved in the GSHG. These results indicate that the brain's focusing function during the reading stimulation was not properly operating in the morning in the female college students who had a delayed bedtime and bad sleep habits.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.2
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• pp.40-46
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• 2011

This paper proposes a real-time face detection and tracking system that uses neural oscillators which can be applied to access regulation system or control systems of user authentication as well as a new algorithm. We study a way to track faces using the neural oscillatory network which imitates the artificial neural net of information handing ability of human and animals, and biological movement characteristic of a singular neuron. The system that is suggested in this paper can broadly be broken into two stages of process. The first stage is the process of face extraction, which involves the acquisition of real-time RGB24bit color video delivering with the use of a cheap webcam. LEGION(Locally Excitatory Globally Inhibitory)algorithm is suggested as the face extraction method to be preceded for face tracking. The second stage is a method for face tracking by discovering the leader neuron that has the greatest connection strength amongst neighbor neuron of extracted face area. Along with the suggested method, the necessary element of face track such as stability as well as scale problem can be resolved.

• Korean Journal of Cognitive Science
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• v.19 no.2
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• pp.143-161
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• 2008

The goal of this paper is to extract the hyponymy relation between words in the corpus. Adopting the basic algorithm of Hearst (1992), I propose a method of pattern-based extraction of semantic relations from the corpus. To this end, I set up a list of hypernym-hyponym pairs from Sejong Electronic Dictionary. This list is supplemented with the superordinate-subordinate terms of CoroNet. Then, I extracted all the sentences from the corpus that include hypemym-hyponym pairs of the list. From these extracted sentences, I collected all the sentences that contain meaningful constructions that occur systematically in the corpus. As a result, we could obtain 21 generalized patterns. Using the PERL program, we collected sentences of each of the 21 patterns. 57% of the sentences are turned out to have hyponymy relation. The proposed method in this paper is simpler and more advanced than that in Cederberg and Widdows (2003), in that using a word net or an electronic dictionary is generally considered to be efficient for information retrieval. The patterns extracted by this method are helpful when we look fer appropriate documents during information retrieval, and they are used to expand the concept networks like ontologies or thesauruses. However, the word order of Korean is relatively free and it is difficult to capture various expressions of a fired pattern. In the future, we should investigate more semantic relations than hyponymy, so that we can extract various patterns from the corpus.

• Journal of Gifted/Talented Education
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• v.18 no.3
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• pp.591-612
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• 2008

In order to investigate the composition and characteristics of instructional objectives in a teaching-learning material for gifted elementary students in science, 217 instructional objectives across 13 themes in 4 areas of 'energy','materials', 'life' and 'earth' were analyzed by Bloom's revised taxonomy of educational objectives. Four types of factual, conceptual, procedural and meta-cognitive knowledge in knowledge dimension were all comprised in the objectives. Conceptual knowledge was primary constituent of the objectives and the proportion of factual knowledge was the least. On the other hand, all 6 categories of 'remember', 'understand', 'apply', 'analyze', 'evaluate' and 'create' in cognitive process dimension were also comprised in the objectives. The category of 'understand' was primary constituent and that of 'remember' was the least one. While conceptual knowledge in knowledge dimension was primary constituent of the objectives in 'energy', 'materials' and 'earth' areas, procedural knowledge was the most objectives in 'life' area. The least type of knowledge was factual knowledge in all 4 areas. In cognitive process dimension, the category of 'understand' was primary constituent and that of 'remember' was the least one in all 4 areas. In conclusion, it was showed that the instructional objectives in the teaching-learning material reflected the characteristics of educational objectives for gifted students in science.

• Korean Journal of Psychosomatic Medicine
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• v.26 no.2
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• pp.194-200
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• 2018

Objectives : The significance of leukoaraiosis on brain magnetic resonance imaging (MRI) is uncertain, but it is often seen with vascular risk factors or in the context of cognitive impairment. We aimed to investigate the effect of leukoaraiosis on the severity and course of delirium. Methods : Periventricular hyperintensity and deep white matter hyperintensity on brain MRI were rated in 42 patients with delirium by semiquantative visual rating scale. Correlations between their grades and the scores of Korean version of Delirium Rating Scale-Revised-98 (K-DRS-R-98) were analyzed, and the interaction effects between the groups according to the levels of leukoaraiosis and two evaluation points were also analyzed. Results : The grade of deep white matter hyperintensity in the occipital lobe was positively correlated with the scores on the total, severity items, cognitive items, and non-cognitive items of K-DRS-R-98. The cognitive items scores of K-DRS-R-98 in the low grade group of periventricular hyperintensity showed significantly steeper decrease than the high grade group. Conclusions : A difference in severity or recovery speed of delirium according to the level of leukoaraiosis may result from disruption in brain functional connectivity. Our results have a clinical implication in that the severity and course of delirium can be possibly predicted using the level of leukoaraiosis.

• Korean Journal of Cognitive Science
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• v.33 no.4
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• pp.205-228
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• 2022

This study aimed to confirm the effect of social and relational behavior types of robots on human cognition in human-robot interaction. In the experiment, the participants evaluated trust in robots by watching a video on the robot Nao interacting with a human, in which the robot made an error and then made an effort to restore trust. The trust recovery behavior was set as three conditions: an internal attribution in which the robot acknowledges and apologizes for an error, a condition in which the robot apologizes for an error but attributes it externally, and a non-action condition in which the robot denies the error itself and does not take any action for the error. As the result, in all three cases, the error was perceived as less serious when the robot apologized than when it did not, and the ability of the robot was also highly evaluated. These results provide evidence that human attitudes towards robots can respond sensitively depending on the robot's behavior and how they overcome errors, suggesting that human perception towards robots can change. In particular, the fact that robots are more trustworthy when they acknowledge and apologize for their own errors shows that robots can promote positive human-robot interactions through human-like social and polite behavior.