• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.309-317
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• 2009

This study was to investigate the effects of restoring cognition function and neurotrophic factor in the hippocampus according to memory and learning training in rats affected by brain injury. Brain injury was induced in Sprague-Dawley rats(36 rats) through middle cerebral artery occlusion(MCAo). And then experiment groups were randomly divided into three groups; Group I: Brain injury induction(n=12), Group II: the application for treadmill training after brain injury induction(n=12), Group III: the application for memory and learning training after brain injury induction(n=12). Morris water maze acquisition test and retention test were performed to test cognitive function. And the histological examination was also observed through the immunohistochemistric response of BDNF(brain-derived neurotrophic factor) in the hippocampus. For Morris water maze acquisition test, there were significant interactions among the groups with the time(p<.001). The time to find the circular platform in Group III was more shortened than in Group I, II on the 9th, 10th, 11th and 12th day. For Morris water maze retention test, there were significant differences among the groups(p<.001). The time to dwell on quadrant circular platform in Group III on the 13th day was the longest compared with other groups. And as the result of observing the immunohistochemistric response of BDNF in the hippocampus CA1, the response of immunoreactive positive in Group III on the 7th day increased more than that of Group I, II. These results suggested that the memory and learning training in rats with brain injury has a more significant impact on restoring cognitive function via the changes of neurotropic factor expression and synaptic neuroplasticity.

• Journal of Korea Entertainment Industry Association
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• v.13 no.6
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• pp.277-286
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• 2019

The aim of this study was to investigate the effects of computer-based cognitive rehabilitation and traditional cognitive training on the working memory and executive function of patients with mild traumatic brain injury. The sample consisted of 20 patients with mild traumatic brain injury who had received rehabilitation treatment in a rehabilitation unit. The subjects were assigned to either the experimental (n = 10) or control group (n = 10). The experimental group received computer-based cognitive rehabilitation and traditional cognitive training for 60 minutes, whereas the control group received only traditional cognitive training for 60 minutes. Both the groups received their respective interventions for 60 minutes a day and 5 times per week across a period of 4 weeks. Working memory and executive function were assessed using the digit span test (forward and backward), visual memory 1 and 2 of the Motor-free Visual Perception Test-3, trail making test, and Stroop test (A and B) both before and after the intervention. The experimental group showed a significantly greater improvement in visual memory and performance on the Stroop test A than the control group. These findings suggest that computer-based cognitive rehabilitation and traditional cognitive training are more effective in promoting positive changes in the working memory and executive function of individuals with mild traumatic brain injury than traditional cognitive training.

• 한국노년학
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• v.28 no.4
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• pp.925-940
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• 2008

As the proportion of old people in contemporary societies steadily increases, the influence on cognitive rehabilitation strategy of the memory deficit associated with normal and pathological aging grows greater as well. This paper reviewed the current memory rehabilitation techniques for older adults. In the first part of this article, human memory systems as a framework for understanding memory aging were considered. In the second part, research findings concerning memory performance in normal aging and Alzheimer's disease were reviewed. Finally, recent evidence for the kinds of memory rehabilitation procedures with proven efficacy were offered. The existent memory rehabilitation technique have focused on prompt of residual explicit memory, use of preserved implicit memory, utilization of memory external memory aids. A suggestion of memory training based on brain plasticity as a novel approach is offered.

• The Korean Journal of Financial Studies
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• v.11 no.1
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• pp.1-36
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• 2005

한 시계열의 원래 관찰치가 본래 가지고 있는 정보를 하나도 잃지 않고 또한 손상시키지 않고 그대로 보존되며 계산이 용이하고, 뿐만 아니라 가능도함수나 비모수 추정함수를 계산함에 있어 수치적 불안정 잠재성이 존재하지 않도록 변환된 시계열을 얻을 수 있으면, 다시 말해 각종 통계량의 계산에 용이하게 적용 가능하되 원래 시계열이 보유하고 있는 모든 성질들은 추호도 손상시킴이 없이 이 시계열을 변환시킬 수 있는 변환방법이 존재한다면, 모수의 추정치와 검정통계량을 정확히 얻을 수 있을 것이다. 이와 같은 변환방법이 웨이브렛 변환이다. 이 변환은 푸리에 분석의 결점을 극복하되 후리에 변환이 적용되는 분야에는 거의 모두 적용 가능한 변환방법이다. 이 논문에서는 시계열의 웨이브렛 변환을 소개하고 이 변환이 재무시계열의 모형화에 한몫을 단단히 할 수 있다는 점을 밝히고자 한다. 그리고 웨이브렛 변환을 성공적으로 적용할 수 있는 주가과정을 하나의 예로 제시하여 웨이브렛 변환의 구체적 적용방법을 탐구하고자 한다. 웨이브렛의 주가 시계열의 적용방법의 한 예로 주가의 장기기억과정을 분석한다. 한국과 외국의 일별 주가지수의 수익률 시계열들이 장기기억과정을 따르는 시계열임이 발견되었다. 여러 형태의 웨이브들을 사용하여 검정하였는데 이 모두가 한결같이 주가지수가 장기기억성과정임을 지지하고 있다.

• Korean Journal of Biological Psychiatry
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• v.2 no.2
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• pp.177-185
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• 1995

외상후 뇌손상은 대표적이며, 가장 중요한 신경정신계 질환의 하나이다. 더욱이 외상후 뇌손상 환자들은 각종의 사고 및 산업재해 등으로 인해 그 수가 급증하고 있으며, 특히 인지기능의 장애로 인한 다양한 기질성 정신장애로 고통을 겪게 된다. 따라서 외상후 뇌손상은 손상의 시점에서부터 정확하고 올바른 평가는 물론 손상후의 경과 및 치료대책의 수립에 있어서 체계적이며 종합적인 신경인지기능의 평가는 필수적이다. 왜냐하면 신경인지기능평가는 뇌의 손상부위와 이와 관련된 기능장애 및 행동의 변화에 대한 객관적인 자료를 제시해 주기 때문이다. 신경인지기능 평가의 영역은 지각, 운동기능은 물론 주요인지기능인 기억, 언어, 실행 및 감정조절능력에 이르기까지 다양하며, 외상후 뇌손상환자들은 손상부위 및 정도에 따라 신경인지기능의 장애를 초래하게 된다. 대표적인 신경인지기능평가 도구로는 KWIS, Halstead-Reitan, Luria-Nebraska batteries, 특히 전두엽기능검사인 Wisconsin Card Sorting Test (WCST)를 비롯하여, 현재는 PC/S Vienna Test System 및 Stim등의 각종 전산화 인지기능검사가 개발되어 임상에서 활발히 사용되고 있다. 즉 외상후 뇌손상환자를 위한 신경인지기능평가의 목적은 뇌손상과 관련된 신경인지기능장애를 정확히 평가하여, 환자 개개인에 적합한 인지재활치료 계획을 수립하는데 있다. 물론 여기에는 신경정신상태검사(neuropsychiatric mental status examination)를 통하여 외상 후 뇌손상의 경과 및 예후에 결정적인 영향을 미칠 수 있는 나이, 의식소실 및 외상후 기억 손상 시간의 정확한 측정은 물론 심리 사회 문화적인 상태와 두부외상전 환자의 지적수준 및 사회 적용기능이 함께 평가되어야 할 것이다.

• Journal of the Korean Society for Nondestructive Testing
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• v.21 no.6
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• pp.634-641
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• 2001

Shape memory alloy has been used to improve the tensile strength of composite by the occurrence of compressive residual stress in matrix using its shape memory effect. In order to fabricate shape memory alloy composite, TiNi alloy and A16061 were used as reinforcing material and mix, respectively. In this study, TiNi/A16061 shape memory alloy composite was made by using hot press method. However, the specimen fabricated by this method had the bonding problem at the boundary between TiNi fiber and Al matrix when the load was applied to it. A cold rolling was imposed to the specimen to improve the bonding effect. It was found that tensile strength of specimen subjected to cold rolling was more increased than that of specimen which did not underwent cold rolling. In addition, acoustic emission technique was used to quantify the microscopic damage behavior of cold rolled TiNi/A16061 shape memory alloy composite at high temperature.

• Journal of Life Science
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• v.26 no.7
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• pp.812-818
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• 2016

The aim of this study was to investigate the anti-amnesic effect of Stachys sieboldii MIQ. according to the mixing ratio of calcium on scopolamine-induced learning and memory impairment, in vivo. At the end of the adaptation period, SD rats were divided into a normal group (N), a control group (C: scopolamine), a positive control group (PC: scopolamine + tacrine), and a sample group (S: scopolamine + Stachys sieboldii MIQ., 1CS: scopolamine + low calcium-mixed Stachys sieboldii MIQ., 5CS: scopolamine + high calcium-mixed Stachys sieboldii MIQ.), and were tested with learning and memory tests. The C and CS groups were found to have a decreased scopolamine-induced memory deficit in the Y-maze and water maze tests. Brain tissue analysis showed that the CS group decreased acetylcholinesterase (AChE) activity and increased acetylcholine (Ach) content, both of which are indicative of neuronal cell activity. From a light microscopy study, the nucleus of neurons in the hippocampus of the brain was more shrunken or condensed in the C group compared to the CS group. In the CS group, the damage to the neurons in the hippocampus of the brain was suppressed. These results suggest that Stachys sieboldii MIQ. according to the mixing ratio of calcium provides a significant anti-amnesic effect against scopolamine-induced cholinergic system deficits and cognitive impairment.

• Korean Journal of Cognitive Science
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• v.7 no.3
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• pp.7-36
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• 1996

Recebt neuropsychological studies on neurobiological bases of learning and memory in humans are reviewed. At present, cognitive psychologists belive that memory is not a unitary system. But copmosed of several independent subsystems. Adoption this perspective,this paper summarized findings regarding what kinds of memory discorders result from lesions of which brain areas and which brain areas are activated by what kind of learning/memory tasks. Short-term memory seems to involve widespread areas around the boundaries among the parietal,occipital,and temporal lobes,depending on the type of the type of the tasks and the way of presentation of the stimuli. Implicit memory,a subsystem of long-term memory,is not a unitary system itself. Thus,brain areas involved in implicit memory tasks used. It is well-known that medial temporal lobe is necessary for formation(i,e.,consolidation)of explicit memory,another subsystem of long-term memory. Storage and/or retrieval of episodic and semantic memory involve temporal neocortex. Perfromtal cortex seemas to be involved in several aspects of memory such as short term memory and retrieval of espisodic and semantic memory. Finally, a popular view on the locus of long-term memory storage is described.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.1
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• pp.7-13
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• 2003

A hot press method was use for the optimal manufacturing condition for a shape memory alloy(SMA) composite. The bonding between the matrix and the reinforcement within the SMA composite by the hot press method was strengthened by cold rolling. In this study, the objective was to develop an on-line monitoring system for the prevention of the crack initiation and propagation by shape memory effort of SMA composite. Shape memory effect was used to prevent the SMA composite from cracking. For the system to be developed, an optimal hE parameter should be determined based on the degree of damage and crack initiation. When the SHA composite was heated by the plate heater attached at the composite, the propagating cracks appeared to be controlled by the compressive force of SMA.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1190-1196
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• 2013

The purpose of this study was to investigate the mechanism and effects of different types of ginseng on memory improvement in an experimental rat model. In this study, SD rats were induced for memory deficits through scopolamine treatment (1 mg/kg, i.p.) then administrated with ginseng extract for 7 weeks. The rats were divided into five groups: saline (1 mL/kg, NC: negative control), white ginseng (300 mg/kg, WG), red ginseng (300 mg/kg, RG), black ginseng (300 mg/kg, BG), and scopolamine (1 mg/kg, PC: positive control). The step through latency of the BG and RG groups was significantly longer than the PC group in the retention trial of multiple trial passive avoidance test. In the spatial reference memory triads of the Morris water maze test, the latency time of BG and RG was significantly lower than the PC group. In addition, in the prove test, the time spent in the platform quadrant of BG and RG groups were significantly longer than the PC group. Brain choline acetyltransferase (ChAT) activities BG and RG groups significantly increased compared to other groups. On the other hand, the levels of malondialdehyde (MDA) were significantly lower in the BG and RG groups compared to other groups. These result suggested that black ginseng could be useful to enhance learning memory and cognitive function by regulation of cholinergic enzymes.