• 한국산학기술학회논문지
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• 제4권4호
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• pp.372-379
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• 2003

Desktop-PC의 메모리 모듈 제품을 대상으로 실장 검사를 하는데 있어 발생하는 문제점인 메인보드 메모리 연결부의 파손을 보완하기 위해 확장 카드를 개발하였다. 확장 카드 개발 전 메인보드 연결부의 파손은 하루 15％의 수준으로 잉여설비를 15％이상 확보해야 하며 수리를 전담으로 하는 인력을 필요로 하는 문제점을 가지고 있다. 확장카드의 개발로 소켓의 파손에 따른 업무 지연과 잉여설비의 capacity향상 및 작업성 개선을 통해 연간 7,800만원의 비용을 절감 할 수 있었다.

• 대한한방소아과학회지
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• 제25권1호
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• pp.40-48
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• 2011

Objectives: The purpose of this study is to evaluate the effect of Gonjadaesungchimjoongbang on spatial learning abilities and memories in ischemic brain injury. Methods: Rats were separated into three groups; (1) Normal, (2) Saline medication after ischemic brain injuries (control), (3) Gonjadaesungchimjoongbang medication after ischemic brain injuries (experiment). Ischemic brain injuries was induced by MCA occlusion and reperfusion. Morris water maze test was conducted for spatial learning and memory tests. Then, the change of BDNF in the hippocampus($7^{th}$, $14^{th}$ day) was examined by immunohistoche- mistry. Results: In Morris water maze test, spatial learning abilities and memory functioning were considerably increased in the experiment group as oppose to control group on $7^{th}$ and $14^{th}$ day(p<0.01). Moreover, immunohistochemistric response of BDNF in the hippocampus indicated that the more increased immune reaction was found in the experiment group as oppose to the control group on $7^{th}$ and $14^{th}$ day. Conclusions: Gonjadaesungchimjoongbang can improve the learning abilities and memories in ischemic brain injury.

• 말소리와 음성과학
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• 제8권1호
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• pp.63-69
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• 2016

The aims of the present study are two-fold: 1) to explore differences on speech perception between younger and older adults according to noise conditions; and 2) to investigate which cognitive domains are correlated with speech perception. Data were acquired from 15 younger adults and 15 older adults. Sentence recognition test was conducted in four noise conditions(i.e., in-quiet, +5 dB SNR, 0 dB SNR, -5 dB SNR). All participants completed auditory and cognitive assessment. Upon controlling for hearing thresholds, the older group revealed significantly poorer performance compared to the younger adults only under the high noise condition at -5 dB SNR. For older group, performance on Seoul Verbal Learning Test(immediate recall) was significantly correlated with speech perception performance, upon controlling for hearing thresholds. In older adults, working memory and verbal short-term memory are the best predictors of speech-in-noise perception. The current study suggests that consideration of cognitive function for older adults in speech perception assessment is necessary due to its adverse effect on speech perception under background noise.

• 한국정보통신학회논문지
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• 제14권2호
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• pp.445-452
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• 2010

본 논문에서는 Full 하드웨어 기반 베이스라인 프로파일 레벨 3 규격 H.264 인코더 코덱에서 사용할 수 있는 Direct Memory Access (DMA) 제어기를 설계하였다. 설계한 모듈은 CMOS Image Sensor(CIS)로부터 영상을 입력 받아 메모리에 저장한 후 인코더 코덱 모듈의 동작에 맞춰 원영상과 참조영상을 각각 한 매크로블록씩 메모리로부터 읽어서 공급하거나 저장하며, DMA 제어기의 한 매크로블록씩 처리하는데 478 cycle을 소요한다. 설계한 구조를 검증하기 위해 JM 9.4와 호환되는 Reference Encoder C를 개발하였으며, Encoder C로부터 Test Vector를 추출하여 설계한 회로를 검증하였다. 제안한 DMAC 제어기의 Cycle은 Xilinx MIG를 사용한 Cycle 보다 40%의 감소를 나타내었다.

• International Journal of Korean Welding Society
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• 제3권1호
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• pp.39-44
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• 2003

The welded specimens were made by butt welding of the 2 wires of 50mm length using the pulsed YAG laser. The laser welded wires were tested for investigating the shape memory effect and the ability of super elasticity. The fatigue properties of the welded wires were investigated using the rotary bending fatigue tester specially designed for wires. Moreover, the effect of defocusing distance during laser welding on the static and fatigue properties was Investigated. The shape memory effect and super elasticity of the laser welded wires were approximately identical with that of base metal at the test temperature below 353K. However, the welded wires were broken within elastic limit at the test temperature above 353k. Under the cyclic bending loading conditions, the welded wires could be useful only below the elastic limit, while the base metal had sufficient fatigue life even the stress induced M-phase region. The fatigue strength of the welded wires was about half of that of the base metal. The deterioration of the static and fatigue properties in the welded wires was proven to be from the large difference of the transformation behavior between the base metal and welded part that is caused by vaporization of Ni-content at the welded part during the welding process. The defocusing distance below 3mm acted more largely on lowering the strength of the welded wires than that of 6mm or 8mm.

• 한국산학기술학회논문지
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• 제13권11호
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• pp.5025-5032
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• 2012

본 연구는 다문화아동과 일반아동의 작업기억과 음운인식능력이 집단 간에 차이가 있는지를 알아보고자 하였다. 연구대상은 전라남도 D시에 거주하며 초등학교 1~3학년에 재학중인 다문화 아동 15명과 일반아동 15명이었다. 작업기억을 검사하기 위하여 K-TTFC-2를 실시하였고, 음운인식능력을 검사하기 위하여 아동들의 연령을 고려하여 음소수준의 검사만을 실시하였다. 연구결과는 첫째, 다문화아동과 일반아동의 작업기억의 차이를 비교한 결과 유의미한 차이가 있었다. 둘째, 다문화아동과 일반아동의 음운인식능력 중에서 음소 수준의 차이를 비교한 결과 통계적으로 유의미한 차이가 있었다. 셋째, 다문화 아동과 일반아동의 하위과제별 차이를 비교한 결과 음 짝짓기(어중 종성), 단음절 단어에서 중성 대치하기, 음 전환하기에서 통계적으로 유의미한 차이가 있었다. 따라서 본 연구를 통해 다문화 아동의 음운 및 작업기억 결과를 고려한 치료를 위한 기초자료로 활용할 수 있을 것으로 사료된다.

• Biomolecules & Therapeutics
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• 제21권5호
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• pp.381-390
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• 2013

The purpose of this study was to examine whether ginsenoside Rg3 (GRg3) could improve learning and memory impairments and inflammatory reactions induced by injecting lipopolysaccharide (LPS) into the brains of rats. The effects of GRg3 on proinflammatory mediators in the hippocampus and the underlying mechanisms of these effects were also investigated. Injection of LPS into the lateral ventricle caused chronic inflammation and produced deficits in learning in a memory-impairment animal model. Daily administration of GRg3 (10, 20, and 50 mg/kg, i.p.) for 21 consecutive days markedly improved the LPS-induced learning and memory disabilities demonstrated on the step-through passive avoidance test and Morris water maze test. GRg3 administration significantly decreased expression of pro-inflammatory mediators such as tumor necrosis factor-${\alpha}$, interleukin-1${\beta}$, and cyclooxygenase-2 in the hippocampus, as assessed by reverse transcription-polymerase chain reaction analysis and immunohistochemistry. Together, these findings suggest that GRg3 significantly attenuated LPS-induced cognitive impairment by inhibiting the expression of pro-inflammatory mediators in the rat brain. These results suggest that GRg3 may be effective for preventing or slowing the development of neurological disorders, including Alzheimer's disease, by improving cognitive and memory functions due to its anti-inflammatory activity in the brain.

• The Korean Journal of Physiology and Pharmacology
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• 제16권2호
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• pp.79-89
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• 2012

We examine whether Phellodendron amurense (PA) and its major alkaloid compound, berberine (BER), improved memory defects caused by administering scopolamine in rats. Effects of PA and BER on the acetylcholinergic system and pro-inflammatory cytokines in the hippocampus were also investigated. Male rats were administered daily doses for 14 days of PA (100 and 200 mg/kg, i.p.) and BER (20 mg/kg, i.p.) 30 min before scopolamine injection (2 mg/kg, i.p.). Daily administration of PA and BER improved memory impairment as measured by the passive avoidance test and reduced the escape latency for finding the platform in the Morris water maze test. Administration of PA and BER significantly alleviated memory-associated decreases in cholinergic immunoreactivity and restored brain-derived neurotrophic factor and cAMP-response element-binding protein mRNA expression in the hippocampus. PA and BER also decreased significantly the expression of proinflammatory cytokines such as interleukin-$1{\beta}$, tumor necrosis factor-${\alpha}$ and cyclooxygenase-2 mRNA in the hippocampus. These results demonstrated that PA and BER had significant neuroprotective effects against neuronal impairment and memory dysfunction caused by scopolamine in rats. These results suggest that PA and BER may be useful as therapeutic agents for improving cognitive functioning by stimulating cholinergic enzyme activity and alleviating inflammatory responses.

• 한국수산과학회지
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• 제47권3호
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• pp.195-203
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• 2014

We investigated the effect low salt (2 or 4% salt) concentrations jeotgal made from Todarodes pacificus on the learning and memory impairments in scopolamine-induced (2 mg/kg, i.p.) dementia rats. Rats treated with oral BF-7 (200 mg/kg, p.o.) as a positive control and Todarodes pacificus jeotgal had significantly reduced scopolamine-induced memory deficits in the passive avoidance test. The Morris water maze test or treatment with 2% salt jeotgal made from Todarodes pacificus significantly ameliorated the scopolamine-induced memory deficits in the formation of long- and short-term memory. The acetylcholine content and acetylcholinesterase acitivity paralleled the results of the behavior experiment. There were no significant differences in the brain acetylcholine contents of the experimental groups, while the brain acetylcholine content of the group treated with 2% salt Todarodes pacificus jeotgal was higher than that of the control group. The inhibitory effect of 2% salt jeotgal made from Todarodes pacificus on the acetylcholinesterase activity in the brain was lower than that of the control group. These trends were similar to those of the gamma-aminobutyric acid content. We suggest that Todarodes pacificus jeotgal enhances learning memory and cognitive function by regulating cholinergic enzymes.

• 생물정신의학
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• 제15권2호
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• pp.92-100
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• 2008

Objectives : The purpose of this study was to investigate 1) the neuropsychological deficits with major depressive disorder(MDD) in depressed state and 2) the changes of neuropsychological dysfunctions during depressed episodes and remitted periods in the MDD group. Methods : 12 patients with MDD and 70 normal controls who were diagnosed and classified by DSM-IV and SCID-IV interview participated in this study. The psychopathology was measured using the Hamilton rating scale for depression(HAM-D) and Brief Psychiatric Rating Scale(BPRS). The memory function, executive function, and sustained attention were measured by a trained psychologist using the Korean version of Memory Assessment Scale(K-MAS), Wisconsin Card Sorting Test(WCST), and Vigilance(VIG) and Cognitrone (COG) in Vienna Test System. After 6 weeks of treatment, we retested the cognitive tests in order to measure the cognitive functions in remitted states. Results : Patients with MDD achieved significantly lower score in sentence immediately recall, verbal memory score and total memory score of the K-MAS, total errors of the WCST, response time of Vigilance and response time at "Yes" response of Cognitrone than normal controls at baseline. After 6 weeks of medication, the psychiatric symptoms in the patient group were attenuated, and most of the neuropsychological functions including attention, memory, and frontal/executive function were improved except for response time of Cognitrone. Conclusions : This study provides evidence for distinct neuropsychological deficits in patients with MDD on their depressed states and remitted periods. The impairment on response time remains after remission, and this would be a trait marker of major depressive disorder.