• KSII Transactions on Internet and Information Systems (TIIS)
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• 제8권3호
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• pp.799-818
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• 2014

Spectrum sensing is a key technical challenge for cognitive radio (CR). It is well known that multi-cycle cyclostationarity (MC) detector is a powerful method for spectrum sensing. However, conventional MC detector is difficult to implement due to its high computational complexity. This paper pays attention to the fact that the computation complexity can be reduced by simplifying the test statistic of conventional MC detector. Based on this simplification process, an improved MC detector is proposed. Compared with the conventional one, the proposed detector has the low-computational complexity and sufficient-accuracy on sensing performance. Subsequently, the sensing performances are further investigated for the cases of Rayleigh, Nakagami-m, Rician, composite Rayleigh fading-lognormal shadowing and composite Nakagami fading-lognormal shadowing channels, respectively. Furthermore, the square-law combining (SLC) is introduced to improve the detection capability over fading-shadowing channels. The corresponding closed-form expressions of average detection probability are derived for each case by the moment generation function (MGF) approach. Finally, illustrative and analytical results show that the efficiency and reliability of proposed detector and the improvement on sensing performance by SLC over composite fading-shadowing channels.

• 한국게임학회 논문지
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• 제9권4호
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• pp.45-56
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• 2009

유아의 감성, 인지 발달을 위해서는 시각, 청각, 그리고 촉각 등의 감각통합이 필요하다. ICT의 발전 덕택에 유아는 학습과정 중에 다양한 감각을 사용할 수 있는 더 많은 기회를 갖게 되었다. 그러나, ICT 교육법은 단지 시청각에 중점을 두고 있어 통합인지가 부족하며, 이러한 사실은 ICT가 왜 주교보재로 사용될 수 없는지를 보여준다. 따라서 본 연구에서는 컴퓨터 퍼즐게임을 이용한 wUbi-Pen(촉각펜)의 인지 효과를 평가하였다. 실험 결과, wUbi-Pen을 이용해 햅틱 퍼즐 놀이를 한 경우 햅틱 기능이 없는 펜을 이용해서 퍼즐 놀이를 한 경우보다 K-WPPSI의 5개 동작성 평가 중 모양 맞추기, 미로, 빠진 곳 찾기 등 3개 영역에서 유의미한 차이를 보였다. 이러한 결과는 ICT 교재의 개발에 있어 촉각 기능의 필요성을 제시하고, 더 나아가 인지에 관련된 다양한 증상에 효과적인 교보재로 사용될 수 있음을 보여준다.

• 한국축산식품학회지
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• 제34권1호
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• pp.106-114
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• 2014

Folic acid, one of the B group of vitamins, is an essential substance for maintaining the functions of the nervous system, and is also known to decrease the level of homocysteine in plasma. Homocysteine influences the lowering of the cognitive function in humans, and especially in elderly people. In order to determine the strains with a strong capacity to produce folic acid, 190 bacteria were isolated from various kinds of jeotgal and chungkuk-jang. In our test experiment, JA71 was found to contain $9.03{\mu}g/mL$ of folic acid after 24 h of incubation in an MRS broth. This showed that JA71 has the highest folic acid production ability compared to the other lactic acid bacteria that were isolated. JA71 was identified as Lactobacillus plantarum by the result of API carbohydrate fermentation pattern and 16s rDNA sequence. JA71 was investigated for its physiological characteristics. The optimum growth temperature of JA71 was $37^{\circ}C$, and the cultures took 12 h to reach pH 4.4. JA71 proved more sensitive to bacitracin when compared with fifteen different antibiotics, and showed most resistance to neomycin and vancomycin. Moreover, it was comparatively tolerant of bile juice and acid, and displayed resistance to Escherichia coli, Salmonella Typhimurium, and Staphylococcus aureus with restraint rates of 60.4%, 96.7%, and 76.2%, respectively. These results demonstrate that JA71 could be an excellent strain for application to functional products.

• 한국생활과학회지
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• 제18권1호
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• pp.145-155
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• 2009

The purpose of this study is to examine the university students' awareness and attitudes on functional clothing materials, and to explore the effects of subjects' characteristics on the relationship between their attitudes to and images of the functional clothing materials. A total of 500 questionnaires were distributed to university students and 409 of which were used in data analysis. The data were statistically analyzed by frequency, factor analysis, reliability analysis, correlation analysis, t-test, ANOVA. The results were as follows: students thought that the first and foremost 'function' of functional clothing materials is their light-weight. The functions that consumers practically demanded are water-repellency and high absorbency & quick drying. It showed that students have an image that functional clothing materials have special, good and satisfactory qualities. Goretex and Coolmax were the most selected as brands of functional clothing materials which students knew. Attitudes to functional clothing materials revealed positively in the cognitive, behavioral and affectional attitudes. The attitudes had no significant differences according to sex and their major, but they had significant differences by subjects' amount of allowance, frequency of sports participation and sports ability. In other words, the more amount of allowance they get, the more frequently students do exercise, and the higher sports ability they have, the more positive attitude they have. The study says, in conclusion, that their conception of functional clothing materials has positive relations with their attitudes toward them.

• The Korean Journal of Physiology and Pharmacology
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• 제8권4호
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• pp.173-179
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• 2004

Amyloid ${\beta}-peptide\;(A{\beta})$ contributes to the pathogenesis of Alzheimer's disease (AD), causing neuronal death through apoptosis. In this study, the neuroprotective role of BF-7, extracted form sericultural product, was examined against $A{\beta}-induced$ toxicity in cultured human neuronal cell SKN-SH. In order to know if the BF-7 has positive role on the cognition and memory in human, the mixture of BF-7, DHA and EPA (BDE) was examined using Rey Kim and K-WAIS test with 50 healthy high school student. We report here that BDE significantly attenuated $A{\beta}-induced$ apoptosis through the reduction of ROS accumulation, and diminished caspase-like protease activity. Moreover, the memory index and memory preservation, and attentative concentration of BDE treated group for 1 month were significantly improved, in contrast to the case of placebo control treated with DHA and EPA. This result represent that the BF-7 play significant positive role on learning memory. Taken together, our result suggested the natural product BF-7 is a good substance for the brain functionally and physiologically.

• 국제물리치료학회지
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• 제4권1호
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• pp.479-487
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• 2013

This study is intended to examine the tDCS and Morris Water maze training in Alzheimer's disease(AD) rats on Tau protein expression. Experiment groups were divided into four groups and assigned 16 rats to each group. Group I was a control group(AD induced by scopolamine); Group II was a experimental control group(AD injured by scopolamine and treatment tacrine); Group III was a group of tDCS application after AD injured by scopolamine; Group IV was a group of morris water maze training after AD injured by scopolamine. In cognition test, the outcome of group II was significantly lower than the groups(p<.001). and group III, IV were significantly low result at 14 days(p<.05). In histological finding, the experimental groups were destroy of micro vessels and finding of cell atropy and swelling. Group III, IV were decreased in degeneration of liver and kidney cells. In immuno- histochemistric response of BDNF and tau protein in hippocampus, BDNF expression of Group II was more increase than the other groups. and increase of BDNF expression was III, IV were higher than group I at 21 days. Tau protein expression of Group II was more decrease than the other groups. and decrease of Tau protein expression was III, IV were lower than group I at 21 days. These result suggest that improved tDCS and morris water maze training after scopolamine induced is associated with dynamically altered expression of BDNF and Tau protein in hippocampus and that is related with cognitive function.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제22권3호
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• pp.249-261
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• 2019

Purpose: The neural processing of children with overweight/obesity (CWO), may affect their eating behavior. We investigated the visual information processing of CWO under response control condition, by event-related potential (ERP) study, an electrophysiologic study for cognitive mechanism. Methods: Seventeen CWO (mean age: $10.6{\pm}1.9$), and 17 age-matched non-obese children (NOC), participated in the study. Neurocognitive function tests and visual ERP under Go/NoGo conditions, were implemented. Area amplitudes of major ERP components (P1, N1, P2, N2, and P3) from four scalp locations (frontal, central, parietal, and occipital), were analyzed. Results: For Go and NoGo conditions, CWO had significantly greater occipital P1, frontocentral N1, and P2 amplitudes compared with NOC. P2 amplitude was significantly greater in CWO, than in NOC, at the frontal location. N2 amplitude was not significantly different, between CWO and NOC. For CWO and NOC, Go P3 amplitude was highest at the parietal location, and NoGo P3 amplitude was highest at the frontal location. In Go and NoGo conditions, P3 amplitude of CWO was significantly less than in NOC. Conclusion: The greater P1, N1, and P2 suggested hyper-vigilance to visual stimuli of CWO, but the smaller P3 suggested insufficient mental representation of them. Such altered visual processing, may affect the eating behavior of CWO.

• BMB Reports
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• 제56권3호
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• pp.178-183
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• 2023

Huntington's disease (HD) is a neurodegenerative disorder, of which pathogenesis is caused by a polyglutamine expansion in the amino-terminus of huntingtin gene that resulted in the aggregation of mutant HTT proteins. HD is characterized by progressive motor dysfunction, cognitive impairment and neuropsychiatric disturbances. Histone deacetylase 6 (HDAC6), a microtubule-associated deacetylase, has been shown to induce transport- and release-defect phenotypes in HD models, whilst treatment with HDAC6 inhibitors ameliorates the phenotypic effects of HD by increasing the levels of α-tubulin acetylation, as well as decreasing the accumulation of mutant huntingtin (mHTT) aggregates, suggesting HDAC6 inhibitor as a HD therapeutics. In this study, we employed in vitro neural stem cell (NSC) model and in vivo YAC128 transgenic (TG) mouse model of HD to test the effect of a novel HDAC6 selective inhibitor, CKD-504, developed by Chong Kun Dang (CKD Pharmaceutical Corp., Korea). We found that treatment of CKD-504 increased tubulin acetylation, microtubule stabilization, axonal transport, and the decrease of mutant huntingtin protein in vitro. From in vivo study, we observed CKD-504 improved the pathology of Huntington's disease: alleviated behavioral deficits, increased axonal transport and number of neurons, restored synaptic function in corticostriatal (CS) circuit, reduced mHTT accumulation, inflammation and tau hyperphosphorylation in YAC128 TG mouse model. These novel results highlight CKD-504 as a potential therapeutic strategy in HD.

• 생물정신의학
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• 제3권2호
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• pp.277-287
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• 1996

본 연구는 주정중독에 동반된 우울증 환자의 치료에서 적어도 행동학적 부작용의 관점에서는 PAR이 AMI보다 우수함을 증명하였다. 이러한 PAR의 행동학적 효과의 우수성은 환자의 삶의 질을 향상시키고 결국 치료결과를 높이는데 관여하리라고 생각된다.

• 한국안광학회지
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• 제20권4호
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• pp.491-499
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• 2015

목적: 시각이상을 가진 아동을 대상으로 시기능훈련을 통한 시각기능이상의 개선 전후 시지각점수의 변화를 살펴보고 시지각에 미치는 영향을 알아보고자 한다. 방법: 시각기능이상을 가진 13세 미만($8.75{\pm}1.66$)의 아동 23명을 대상으로 시기능훈련 전후에 시지각기능검사(TVPS_R; test of visual perceptual skills-revised)를 실시하여 시기능훈련에 따른 시각기능의 변화와 시지각 평가점수의 변화를 분석하였다. 결과: 시기능훈련을 통해서 원거리 PRC(positive relative convergence) 분리점은 평균 $3.39{\pm}2.59{\Delta}$(prism)에서 $13.87{\pm}6.04{\Delta}$로 증가되었고, 근거리 P.R.C 분리점은 평균 $5.48{\pm}3.42{\Delta}$에서 $18.44{\pm}7.58{\Delta}$로 증가하였다. NPC(near point of convergence)는 $25.87{\pm}7.33cm$에서 $7.48{\pm}2.83cm$로 개선되었고, NPA(near point of accommodation)는 $19.57{\pm}7.16cm$에서 $7.09{\pm}1.88cm$로 개선되었다. 시지각평가에서 시각기억분야를 제외하고는 대응차가 시각완성에서 $17.74{\pm}16.94$(p=0.000), 시각적순차기억에서 $15.65{\pm}17.11$(p=0.000), 배경식별에서 $13.65{\pm}16.63$(p=0.001), 형태향상성에서 $12.74{\pm}18.41$(p=0.003), 시각구별에서 $6.49{\pm}10.07$(p=0.005), 시각적공간지각에서 $4.17{\pm}9.33$(p=0.043) 순으로 개선되었고, 이를 종합한 시지각점수는 대응차가 $15.22{\pm}8.66$(p=0.000)로서 더욱 더 유의한 결과를 나타내었다. 결론: 시기능훈련을 통해서 시각기능의 개선과 시각기억분야를 제외한 시지각점수의 향상이 시각완성, 시각적순차기억, 배경식별, 형태향상성, 시각구별, 시각적공간지각 순으로 유의하게 나타났다. 따라서 시각기능향상을 위한 시기능훈련은 시각의 기능뿐만 아니라 시지각의 기능까지 영향을 미치는 것을 확인 할 수 있으며 시각훈련의 중요성을 인식 할 수 있었다.