• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2461-2468
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• 2000

In this paper, single fiber pull-out test is used to measure the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite with temperature. Fiber and matrix of $Ti_{50}-Ni_{50}$ shape memory alloy composite are respectively $Ti_{50}-Ni_{50}$ shape memory alloy and epoxy resin. To strengthen the interfacial bonding shear stress, various surface treatments are used. They are the hand-sanded surface treatment, the acid etched surface treatment and the silane coupled surface treatment etc.. The interfacial bonding shear strength of surface treated shape memory alloy fiber is greater than that of surface untreated shape memory alloy fiber by from 10% to 16%. It is assured that the hand-sanded surface treatment and the acid etched surface treatment are the best way to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory composite. The best treatment condition of surface is 10% HNO$_3$ solution in the etching method to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.3
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• pp.624-634
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• 1998

The photoelastic model material with shape memory effect and the molding processes for the material are developed in this research. The matrix and fiber of the photoelastic model material developed in this research are epoxy resin (Araldite to hardner 10 to 3 (weight ratio)) and wire of $Ti_50-Ni_50$ shape memory alloy, respectively. It is called Ti50-Ni50 Shape Memory Alloy Fiber Epoxy Composite $(Ti_50-Ni_50SMA-FEC).$ Ti50-Ni50 SMA-FEC is satisfied with the requirements of the photoelastic model material and can be used as a photoelastic model material. The maximum recovering strain of $Ti_50-Ni_50$SMA-FEC is occurred at $80^{\circ}C$ in any prestrain of $Ti_50-Ni_50$ shape memory alloy fiber and in any fiber volume ratio. Recovering strain(force) is increased with the increment of the prestrain and the fiber volume ratio. The best prestrain of $Ti_50-Ni_50$SMA-FEC is 5% for the recovering force among 1%, 3%, 5%.

• The Journal of the Korea Contents Association
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• v.7 no.5
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• pp.110-117
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• 2007

The recent developments of audio/video technology in the ubiquitous media have resulted in a variety of formal feature such as screen sizes for media and the new viewing environment can alter television viewers' experience of mediated communication. So the concern about formal feature of media itself is increasing in the recent media effects studies. From this point of view, this study is conducted to test the effect of the different monitor size of DMB Phone(2'1"), PMP(4'3") and PC monitor(19') on the viewers' memory and emotion of content by experimental research. The results showed that the effect by monitor size on the view's memory and emotion is significant. And watching moving image on a bigger monitor resulted in better memory of visual message elements contained in the content and more favorable emotion of the content.

• Korean Journal of Materials Research
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• v.8 no.11
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• pp.993-998
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• 1998

In this study TiNi/A16061 shape memory composite is introduced as one of new material using a shape memory alloy. High tensile strength of composite due to compressive residual stress in matrix by the shape memory effect of TiNi fiber can be produced. This composite can remove the tensile residual stress by the difference of coefficients of thermal expansion between fiber and matrix. one of the significant weak point of metal matrix composite. In this paper, shape memory composites are made by squeeze casting. And then, microstructure and fatigue properties of the composites by shape memory effect above inverse transformation temperature A, of TiNi alloy are discussed. The results of the fatigue crack control properties of TiNi/A16061 shape memory composite by a squeeze casting are summarized as follows the effect of fatigue crack propagation control at 363K increases according to the increase of volume fraction and prestrain in composites.

• Journal of the Korea Convergence Society
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• v.10 no.9
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• pp.167-172
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• 2019

The purpose of this study was to investigate the effect of computer based cognitive rehabilitation program on the generative naming. Twenty - one patients were assigned to the CoTras program and eight were treated with traditional face - to - face language rehabilitation such as paper and table activities. The experimental group and the control group performed sequential language recall memory training, association memory recall training, language categorization memory training, and language integrated memory training for 12 weeks. The Welch's robust ANCOVA showed significant differences in mean fluency and MMSE-K changes (p<0.05). On the other hand, phonemic fluency increased significantly after 12 weeks of treatment compared to baseline in both experimental and control groups, but there was no statistically significant difference between treatment groups. The results of this study suggest that the computer based cognitive rehabilitation program may be more effective in improving the semantic fluency than the conventional cognitive-linguistic rehabilitation.

• The Korean Journal of Nuclear Medicine
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• v.34 no.1
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• pp.10-21
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• 2000

Purpose: Episodic memory is described as an 'autobiographical' memory responsible for storing a record of the events in our lives. We performed functional brain activation study using ${H_2}^{15}O$ PET to reveal the neural basis of the encoding and the retrieval of episodic memory in human normal volunteers. Materials and Methods: Four repeated ${H_2}^{15}O$ PET scans with two reference and two activation tasks were performed on 6 normal volunteers to activate brain areas engaged in encoding and retrieval with verbal materials. Images from the same subject were spatially registered and normalized using linear and nonlinear transformation. Using the means and variances for every condition which were adjusted with analysis of covariance, t-statistic analysis were performed voxel-wise. Results: Encoding of episodic memory activated the opercular and triangular parts of left inferior frontal gyrus, right prefrontal cortex, medial frontal area, cingulate gyrus, posterior middle and inferior temporal gyri, and cerebellum, and both primary visual and visual association areas. Retrieval of episodic memory activated the triangular part of left inferior frontal gyrus and inferior temporal gyrus, right prefrontal cortex and medial temporal area, and both cerebellum and primary visual and visual association areas. The activations in the opercular part of left inferior frontal gyrus and the right prefrontal cortex meant the essential role of these areas in the encoding and retrieval of episodic memory. Conclusion: We could localize the neural basis of the encoding and retrieval of episodic memory using ${H_2}^{15}O$ PET, which was partly consistent with the hypothesis of hemispheric encoding/retrieval asymmetry.

• The Hankook-Saengyark Bo
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• no.263
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• pp.6-6
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• 2005

`오배자`서 새 항암물질 발견 뛰어난 혈관생성 억제효과 - 울릉도, '섬백리향 향수' 개발(도 자생식물 이용 농가소득 기대) - '청소년기 한약복용 기억력에 효과'(경희대 박성규 교수팀 연구결과) - 경상대학교 최명석 교수 과학기술우수논문상 수상

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.150-153
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• 1990

Nitrobenzene과 Isooctane 임계혼합용액의 정전기장에 의한 유도복굴절을 임계점 근처에서 Oc-Kerr 효과로 관측하여 Kerr 상수가 발산하는 임계특성을 알아 보았다. 그리고 여기서 Kerr 상수에 대한 임계지수와 복굴절의 오름시간에 관계되는 임계지수를 결정하였다. 또한 복굴절 신호를 살펴본 결과 연속적인 정전기장의 펄스에 대해 기억효과가 있음을 보았다.

• (The) Korean Journal of Educational Psychology
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• v.31 no.4
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• pp.819-845
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• 2017

Although testing is usually done for purposes of assessment, previous research over the past 100 years indicates that testing is an effective tool for learning. Testing or retrieval practice of previously studied materials can enhance learning of that previously studied information and/or learning of subsequently presented new information. The former is referred to as the backward effect of testing whereas the latter is referred to as the forward effect of testing. Thus far, however, the literature has not isolated these two effects and most previous research focused on the backward effect. Only recent laboratory research provided evidence that there is a forward effect of testing. The present study provides a review of research on this forward and backward effect of testing, focusing on testing procedures of the effects, empirical evidence, current theoretical explanations, and issues to resolve in order to make use of testing effect in educational settings. The reviews clearly show that testing enhances memory of previously learned information by working as memory modifier and learning of newly presented information by affecting learners' metacognition, implying that testing is not just an assessment of learning, but also an effective tool for learning.

• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.412-420
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• 2004

The purpose of this study was to assess the anterograde amnesic effect of Midazolam administrated by intranasal and oral route. Fifteen healthy volunteers(ASA I) were administrated with placebo, oral Midazolam(15mg), intranasal Midazolam(0.25mg/kg) every 2 weeks. First picture cards were shown to volunteers before medication. At 15, 30, 45 minutes, other picture cards were shown to volunteers. BP, $SpO_2$ and sedation scores were measured. After 24 hours, the volunteers were questioned about their memory of pictures. To assess amnesic effect, recall and recognition test were performed using a series of picture cards designed for this purpose. The obtained results were as follows; 1. Compared to placebo, Midazolam group(oral and intranasal) experienced a significant anterograde amnesic effect(P<0.01) 2. There was no difference between oral and intranasal Midazolam(P>0.01). 3. Anterograde amnesic effect of oral and intranasal Midazolam group began at 15minutes. It became increasingly, oral Midazolam group experienced extremely amnesic effect at 45minutes, intranasal Midazolam group was at 30minutes. 4. After 30minutes of Midazolam administration, anterograde amnesia of oral Midazolam group is more effective than intranasal Midazolam group.