• 한국게임학회 논문지
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• 제11권4호
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• pp.127-142
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• 2011

본 연구는 폭력성 게임 내에서 사실적인 묘사(선혈 색, 비명 소리, 일인칭 시점) 방식이 사용자 각성(arousal), 현존감(presence), 그리고 게임 내에서의 사건 장소에 대한 기억력(memory)에 미치는 영향력을 테스트 하였다. 또한 사용자가 느끼는 현존감과 각성의 관계도 분석되었는데, 최신 3D 슈팅 게임인 CounterStrike를 변형시켜 실험을 진행하였다. 실험 결과, 사실적인 선혈(붉은색)과 소리(날카로운 비명)는 사용자의 경험 정도에 관계없이 각성 정도를 증대시키는 것으로 나타났으며, 각성 정도는 사용자의 현존감과 유의미한 상관 관계를 보여주었다. 특히, 현존감의 세부 요인인 관여도(engagement)는 기억력을 높이는데 가장 결정적인 역할을 하였으며, 각성과 기억력을 매개하는 변수인 것으로 분석되었다. 그러나, 일인칭 시점은 각성에는 영향을 주지 않았으며 관여도에 부적인 영향을 주는 것으로 나타났다.

• 대한전자공학회논문지TC
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• 제42권9호
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• pp.49-56
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• 2005

RF 전력증폭기 및 Doherty 전력증폭기의 열 메모리 효과는 변조신호의 대역폭과 동작 전력의 레벨에 따라 민감하게 영향을 미친다. 본 논문에서는 전기적인 비선형성을 정확히 모델링하고 열 메모리 효과가 Doherty 증폭기의 왜곡형성에 어떤 영향을 미치는지에 대해 연구하였다. Doherty 증폭기의 열 메모리 특성을 모델링하기 위하여 순시적으로 소모되는 전력과 순시 접합온도의 정확한 관계식을 정립하여 제안하였다. 제안된 모델의 파라미터는 서로 다른 여기상태에 따라 전력증폭기의 특성이 결정되는데, 트랜지스터의 열 메모리 효과는 대역폭이 넓은 W-CDMA 및 UMTS 시스템에서 충분히 고려되어야 한다. 이러한 열 메모리 효과를 사전왜곡 함수에 적응하여 선형화된 전력증폭기의 출력스펙트럼에서 최대 20 dB정도의 ACLR 개선효과를 보인다. 측정결과는 60W급 LDMOS Doherty 전력증폭기로 측정하였으며, 열 메모리 보상기는 ADS로 검증하였다.

• 한국한의학연구원논문집
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• 제8권1호
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• pp.109-126
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• 2002

The herbal extract (YMT_02) is a modified herbal extracts from Yukmijihwangtang (YMJ) to promote memory-enhancing. The YMJ extracts has been widely used as an anti-aging herbal medicine for hundred years in Asian countries. The purpose of this study is to; 1) quantitatively evaluate the memory-enhancing effect of YMT_02 by hehavior task, 2) identify candidate genes responsible for enhancing memory by cDNA microarray and 3) assess the anti-oxidant effect of YMT_02 on PC12 cell. Memory retention abilities are addressed by passive avoidance task with Sprague-Dawley (SD) male rat. Before the training session, the rats are subdivided into four groups and administrated with YMT_02, Ginkgo biloba, Soya lecithin and normal saline for 10 days. The retention test was performed. 24 hours after the training session. The retention time of the YMT_02 group was significantly (p<0.05) delayed $({\sim}100%)$, whereas Ginkgo biloba and Soya lecithin treatment delayed 20% and 10% respectively. The hippocampi of YMT_02 and control group were dissected and mRNA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied and mRNA was further purified. After synthesizing cDNA using oligo-dT primer, the cDNA were applied to Incyte rat GEMTM 2 cDNA microarray. The microarray results show that prealbumin(transthyretin), phosphotidy lethanolamine N-methyltransferase, and PEP-19 are expressed abundantly in the YMT_02 treated group. Especially, PEP-19 is a neuron-specific protein, which inhibits apoptotic processes in neuronal cell. On the other hand, transcripts of RAB15, glutamate receptor subunit 2 and CDK 108 are abundant in control group. Besides, neuronal genes involved in neuronal death or neurodegeneration such as neuronal-pentraxin and spectrin are abundantly expressed in control group. Additionally, the YMT_02 shows an anti oxidative effect in the PC12 cell. The list of differentially expressed genes may implicate further insight on the action and mechanism behind the memory-enhancing effect of herbal extracts YMT_02, for example, anti-apoptotic, anti-oxidative, and neuroprotective effects.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.146-149
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• 2003

Two-way shape memory effect(TWSME) under residual stresses are considered in the present study. The structure using two-way shape memory alloy(SMA) concept returns to its initial shape by increasing or decreasing temperature under the initially given residual stress. In the present study, we use a thermo-mechanical constitutive equation of SMA and laminated composite plates are considered as simple morphing structural components which are based on first order shear deformable laminated composite plate with large deflection. Numerical results of fully coupled SMA-composite structures are presented

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 추계학술대회 논문집
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• pp.611-615
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• 2004

To obtain material properties of NiTi shape memory alloy showing pseudoelastic or shape memory effect, tensile test was conducted for various temperatures. Transformation temperature also was measured by using DSC(Differential Scanning Calorimeter), and crystallographic feature of transformation was observed by XRD(X-ray Diffraction).

• 대한한의학회지
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• 제25권4호
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• pp.51-60
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• 2004

Objective : The effect Saenggitang (GT), which has been used for amnesia, in Oriental Medicine, on memory and learning ability, was investigated. Methods : Hot water extracts (HWE) of SGT were used for the studies. In passive avoidance performances (step through test), active avoidance performances (lever press test), Motor activity, pentobarbital-induced sleep, 20 and 50 mg/100g of SGT-HWE ameliorated the memory retrieval deficit induced by 40% ethanol. Results : The SGT-HWE did not affect the ambulatory activity of normal mice in normal condition. 20 and 50 mg/100g of SGT-HWE enhanced contextual fear memory, but not cued fear memory in a fear conditioning task, which requires the activation of the NMDA (N-methyl-D-aspartase) receptor. SGT-HWE did not affect the motor activity measured by the titling type ambulometer test performed immediately and 24 hr after the administration. SGT-HWE prolonged the sleeping time induced by 50 mg/kg pentobarbital in mice and decreased SMA (spontaneous motor activity) in active avoidance performances (lever press test). Conclusion : These results indicate that the SGT-HWE have an improving effect on the memory retrieval disability induced by ethanol and may act as a stimulating factor for activating the NMDA receptor. and the SGT-HWE has a tranquilizing and anti-anxiety action.

• 동의신경정신과학회지
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• 제14권1호
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• pp.75-84
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• 2003

Object : The present experiments were designed to study on the memory enhancement of the extract of Gongjadaesungjichimjung-bang(GDJB). Methods : The water extract of GCJB has been tested for its activities on memory enhancement by passive avoidance task in vivo and for its inhibitory effect on the acetylcholine esterase activity. Results : GDJB water extract significantly enhanced the memory at a concentration of 50mg/kg, but this effect did not proportionally increased at a dose of l00mg/kg and significantly inhibited the acetylcholine esterase activity in a dose-dependent manner in in vitro assay with IC50 value of 1.57mg/ml and also in in vivo assay. Conclusion : The extract of GDJB showed a memory enhancement as well as the inhibitory effect on acetylcholine esterase activity, which suggest that this prescription may be applied for the treatment of memory impairment.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.67-71
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• 2003

A hot press method was used to create the optimal fabrication condition for a Shape Memory Alloy(SMA) composite. The bonding strength between the matrix and the reinforcement within the SMA composite by the hot press method was more increased by cold rolling. In this study, the objective was to develop an on-line monitoring system in order to prevent the crack initiation and propagation by shape memory effect in SMA composite. Shape memory effect was used to prevent the SMA composite from crack propagation. For this system an optimal AE parameter should be determined according to the degree of damage and crack initiation. When the SMA composite was heated by the plate heater attached at the composite, the propagating cracks could be controlled by the compressive force of SMA.

• Animal cells and systems
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• 제12권1호
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• pp.11-14
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• 2008

Finding a way to strengthen human cognitive functions, such as learning and memory, has been of great concern since the moment people realized that these functions can be affected and even altered by certain chemicals. Since then, plenty of endeavors have been made to look for safe ways of improving cognitive performances without adverse side-effects. Unfortunately, most of these efforts have turned out to be unsuccessful until now. In this study, we examine the effect of a natural compound, idesolide, on hippocampus-dependent recognition memory. We demonstrate that idesolide is effective in the enhancement of recognition memory, as measured by a novel object recognition task. Thus, idesolide might serve as a novel therapeutic medication for the treatment of memoryrelated brain anomalies such as mild cognitive impairment(MCI) and Alzheimer's disease.

• 한국멀티미디어학회논문지
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• 제25권10호
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• pp.1468-1474
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• 2022

This is an empirical study to find out whether subtitles and infographics can affect the recognition and recall memory of YouTube users. In this study, a total of 104 university students were divided into 4 groups and exposed to 4 types of contents according to the presence or absence of subtitles and infographics. After the subjects watched YouTube content, they responded to the level of their memory through a survey. As a result of the analysis, the subtitles used in YouTube contents did not affect the recall memory of the audience, and the infographic did not affect the recognition memory of the audience. However, when subtitles were used for YouTube content, the audience's recognition memory was found to be high at a statistically significant level, and when infographics were used for YouTube content, the audience's recall memory was found to be high at a statistically significant level. The significance of this study can be found in that the effects of subtitles and infographics that appeared in the audience effect of legacy media such as newspapers and broadcasting were also found in YouTube, a new video content media.