• 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.

• 대한지역사회작업치료학회지
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• 제2권1호
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• pp.49-63
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• 2012

목적 : 본 연구는 한국형 전산화 인지재활 프로그램인 코드라스(CoTras)가 뇌졸중 환자의 시지각 기능 및 일상생활동작 수행능력에 미치는 효과를 알아보고자 실시되었다. 연구방법 : 재활전문 C 요양병원에 거주하고 있는 뇌졸중 환자 14명을 대상으로 실험 전과 후를 측정하였다. 처치 전 후 시지각 기능의 변화를 알아보기 위하여 사용한 시지각 평가도구는 비운동성 시지각 평가를 사용하였고 일상생활동작 수행능력을 알아보기 위하여 Fisher(1999)에 의해 개발된 운동 및 처리기술 평가도구를 이용하여 일상생활수행능력을 평가하였다. 전산화 인지재활 프로그램 전과 후를 측정하였으며, 수집된 자료는 SPSS 15.0 통계프로그램을 사용하여 분석하였다. 연구대상자의 치료 전과 후의 시지각 기능 및 일상생활동작 수행능력의 효과를 알아보기 위하여 짝비교(Paired t-test)를 이용하여 분석하였다. 연구결과 : 첫째, 코트라스(CoTras)치료 전과 후의 시지각 기능의 차이를 짝비교(Paired t-test)를 이용해 분석한 결과, 통계학적으로 유의한 차이가 있었다(0.000, p <.05). 둘째, AMPS 운동기술 평균점수는 0.90에서 1.11으로 증가되었으나 통계학적으로 유의한 차이는 없었다. 처리기술 평균점수는 0.08에서 0.46점으로 증가되었으나 통계학적으로 유의한 차이가 없었고, 임상적으로 유의하게 일상생활동작 수행능력이 향상되었다(logit >0.3). 결론 : 한국형 전산화 인지재활 프로그램인 코트라스는 뇌졸중 환자의 시지각 기능을 향상시키는 효과가 있었고, 일상생활 동작 수행능력에 임상적으로 긍정적인 영향을 주었다. 시지각에 장애를 가지고 있는 뇌졸중 환자에게 코트라스(CoTras)가 시지각 기능 증진에 기여할 수 있는 기초자료로 제시할 수 있다.

• 한국해안해양공학회지
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• 제13권3호
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• pp.195-201
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• 2001

본 논문은 파랑중에 다전 계류된 원유저장선에 대한 저주파수 운동을 수치 모사하였다. 시간영역에서의 운동방정식은 충격응답함수를 포함하여 수평면상의 운동 즉 전후, 좌우 및 선수 운동을 고려하였다. 시간영역의 운동방정식에 나타난 부가질량, 파랑감쇠계수, 1차항 파랑 강제력 그리고 2차항 파랑 강제력을 주파수 영역의 특이점 분포법을 사용하여 계산하였고, 다점 계류된 계류삭은 체인이 해저면에 닿은 운동 효과를 포함하여 준 정적 현수선 이론으로 산정되었다. 계산 예로서 장파정 불규칙 파랑 중에 놓인 바아지식 원유저장선에 대한 시간 영역 해석을 수행하였다.

• 대한임베디드공학회논문지
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• 제5권4호
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• pp.225-233
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• 2010

In this paper, we try to improve the performance of the demand paging loader suggested to use the demand paging way that is not based on operating system. The demand paging switching strategy used in the existing operating system can know the recently used pages by running multi-processing. Then, based on it, some page switching strategies have been made for the recently used pages or the frequently demanded pages. However, the strategies based on operating system cannot be applied in single processing that is not based on operating system because any context switching never occur on the single processing. So, this paper is trying to suggest the demand paging switching strategies that can be applied in paging loader running in single process. In the Return-Prediction-Algorithm, we saw the improved performance in the program that the function call occurred frequently in a long distance. And then, in the Most-Frequently-Used-Page-Remain-Algorithm, we saw the improved performance in the program that the references frequently occurred for the particular pages. Likewise, it had an enormous effect on keeping the memory reduction performance by the demand paging and reducing the running time delay at the same time.

• BMB Reports
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• 제44권11호
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• pp.730-734
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• 2011

Amyloid ${\beta}$-peptide ($A{\beta}$-peptide)-induced oxidative stress is thought to be a critical component of the pathophysiology of Alzheimer's disease (AD). New chalcone derivatives, the Chana series, were recently synthesized from the retrochalcones of licorice. In this study, we investigated the protective effects of the Chana series against neurodegenerative changes in vitro and in vivo. Among the Chana series, Chana 30 showed the highest free radical scavenging activity (90.7%) in the 1,1-diphenyl-2- picrylhydrazyl assay. Chana 30 also protected against $A{\beta}$-induced neural cell injury in vitro. Furthermore, Chana 30 reduced the learning and memory deficits of $A{\beta}_{1-42}$-peptide injected mice. Taken together, these results suggest that Chana 30 may be a promising candidate as a potent therapeutic agent against neurodegenerative diseases.

• 대한전기학회논문지:전력기술부문A
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• 제48권11호
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• pp.1457-1463
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• 1999

This paper develops an real-time expert system for the electronic interlocking system. it obtains the higher safety by determining the railway interlocking strategy in order to prevent trains from colliding, and derailing in the viewpoint of veteran expert, considering the situation of station in real-time. The expert system determines the real-time interlocking strategy by confirming the interlocking relationships among signal facilities based on the interlocking knowledge base from input information such as signal, points, and it is implemented as the rule-based system in order to represented accurately and effectively the interlocking relationships. Especially in case of emergency the function which determines the rational route coordinating with IIKBAG on the workstation is designed in order to minimize the spreading effect. It is implemented in C computer language for the purpose of the implementation of the inference engine using the dynamic memory allocation technique, the build and interface of the station structure database. And, the validity of the built expert system is proved by simulating the diversity cases which may occur in the real system for the typical station model.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권12호
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• pp.4664-4681
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• 2020

Modulation recognition (MR) plays a key role in cognitive radar, cognitive radio, and some other civilian and military fields. While existing methods can identify the signal modulation type by extracting the signal characteristics, the quality of feature extraction has a serious impact on the recognition results. In this paper, an end-to-end MR method based on long short-term memory (LSTM) and the gated recurrent unit (GRU) is put forward, which can directly predict the modulation type from a sampled signal. Additionally, the sliding window method is applied to fast-changing mixed-modulation signals for which the signal modulation type changes over time. The recognition accuracy on training datasets in different SNR ranges and the proportion of each modulation method in misclassified samples are analyzed, and it is found to be reasonable to select the evenly-distributed and full range of SNR data as the training data. With the improvement of the SNR, the recognition accuracy increases rapidly. When the length of the training dataset increases, the neural network recognition effect is better. The loss function value of the neural network decreases with the increase of the training dataset length, and then tends to be stable. Moreover, when the fast-changing period is less than 20ms, the error rate is as high as 50%. As the fast-changing period is increased to 30ms, the error rates of the GRU and LSTM neural networks are less than 5%.

• Journal of Ginseng Research
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• 제48권1호
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• pp.98-102
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• 2024

Background: Ginseng (Panax ginseng Meyer) is a perennial plant belonging to the Araliaceae family that is known to have various beneficial effects including improving memory loss and spatial cognitive ability, and anti-cancer and anti-diabetes activity. Its functional benefits also include improving liver function, regulating blood pressure, stress, and providing antioxidant activity. Usually, various agrochemicals are used in cultivating ginseng preventing from many diseases. Methods: FCGP (field cultivated ginseng in pot) was implemented by imitating MCWG (mountain cultivated wild ginseng). Pesticide analysis of pot cultivation was carried out and the contents of bioactive components such as ginsenoside were also analyzed. Results: FCGP ginsenoside content was higher than that of FCG (field cultivated ginseng) and MCWG. FCGP has been shown to have a relatively high antioxidant effect compared with cultivated ginseng. Conclusion: It was confirmed that ginseng can be grown for 6 years without resorting to use of pesticides. In addition, it was confirmed that effective accumulation of physiologically active ingredients such as ginsenoside is possible. Our result represents FCGP is a novel method of pesticide-free ginseng cultivation

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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• pp.183-184
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• 2013

Two main MBE growth techniques have been used: plasma-assisted MBE (PA-MBE), which utilizes a rf plasma to supply active nitrogen, and ammonia MBE, in which nitrogen is supplied by pyrolysis of NH3 on the sample surface during growth. PA-MBE is typically performed under metal-rich growth conditions, which results in the formation of gallium droplets on the sample surface and a narrow range of conditions for optimal growth. In contrast, high-quality GaN films can be grown by ammonia MBE under an excess nitrogen flux, which in principle should result in improved device uniformity due to the elimination of droplets and wider range of stable growth conditions. A drawback of ammonia MBE, on the other hand, is a serious memory effect of NH3 condensed on the cryo-panels and the vicinity of heaters, which ruins the control of critical growth stages, i.e. the native oxide desorption and the surface reconstruction, and the accurate control of V/III ratio, especially in the initial stage of seed layer growth. In this paper, we demonstrate that the reliable and reproducible growth of GaN on Si (110) substrates is successfully achieved by combining two MBE growth technologies using rf plasma and ammonia and setting a proper growth protocol. Samples were grown in a MBE system equipped with both a nitrogen rf plasma source (SVT) and an ammonia source. The ammonia gas purity was ＞99.9999% and further purified by using a getter filter. The custom-made injector designed to focus the ammonia flux onto the substrate was used for the gas delivery, while aluminum and gallium were provided via conventional effusion cells. The growth sequence to minimize the residual ammonia and subsequent memory effects is the following: (1) Native oxides are desorbed at $750^{\circ}C$ (Fig. (a) for [$1^-10$] and [001] azimuth) (2) 40 nm thick AlN is first grown using nitrogen rf plasma source at $900^{\circ}C$ nder the optimized condition to maintain the layer by layer growth of AlN buffer layer and slightly Al-rich condition. (Fig. (b)) (3) After switching to ammonia source, GaN growth is initiated with different V/III ratio and temperature conditions. A streaky RHEED pattern with an appearance of a weak ($2{\times}2$) reconstruction characteristic of Ga-polarity is observed all along the growth of subsequent GaN layer under optimized conditions. (Fig. (c)) The structural properties as well as dislocation densities as a function of growth conditions have been investigated using symmetrical and asymmetrical x-ray rocking curves. The electrical characteristics as a function of buffer and GaN layer growth conditions as well as the growth sequence will be also discussed. Figure: (a) RHEED pattern after oxide desorption (b) after 40 nm thick AlN growth using nitrogen rf plasma source and (c) after 600 nm thick GaN growth using ammonia source for (upper) [110] and (lower) [001] azimuth.

• Journal of Microbiology and Biotechnology
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• 제31권1호
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• pp.51-62
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• 2021

Here, we investigated the prebiotic and antioxidant effects of Actinidia arguta sprout water extract (AASWE) on lipopolysaccharide (LPS)-induced cognitive deficit mice. AASWE increased viable cell count, titratable acidity, and acetic acid production in Lactobacillus reuteri strain and showed a cytoprotective effect on LPS-induced inflammation in HT-29 cells. We assessed the behavior of LPS-induced cognitive deficit mice using Y-maze, passive avoidance and Morris water maze tests and found that administration of AASWE significantly improved learning and memory function. The AASWE group showed antioxidant activity through downregulation of malondialdehyde levels and upregulation of superoxide dismutase levels in brain tissue. In addition, the AASWE group exhibited activation of the cholinergic system with decreased acetylcholinesterase activity in brain tissue. Furthermore, AASWE effectively downregulated inflammatory mediators such as phosphorylated-JNK, phosphorylated-NF-κB, TNF-α and interleukin-6. The major bioactive compounds of AASWE were identified as quercetin-3-O-arabinopyranosyl(1→2)-rhamnopyranosyl(1→6)-glucopyranose, quercetin-3-O-apiosyl(1 → 2)-galactoside, rutin, and 3-caffeoylquinic acid. Based on these results, we suggest that AASWE not only increases the growth of beneficial bacteria in the intestines, but also shows an ameliorating effect on LPS-induced cognitive impairment.