• Journal of the Korean Crystal Growth and Crystal Technology
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• v.8 no.2
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• pp.193-204
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• 1998

The single crystal of the $LiTaO_3$has large electro-optic effects, so it is applied to optical switch, acousto-optic deflector, and optical memory device as hologram using photorefractive effect. In this study, optic-grade undoped $LiTaO_3$and Fe:LiTaO$LiTaO_3$single crystals were grown by the Czochralski method and optical transmission and absorption spectrums were measured in the wavelength of UV-VIS range. The curie temperature was determined with DSC and by measuring capacitance for the grown undoped crystal and ceramic powder samples of various Li/Ta ratio. In case of having a 48.6 mol% $Li_2O$ as a starting Li/Ta ratio, the results of concentration variations were below 0.01 mol% $Li_2O$ all over the crystal, so it was confirmed that $LiTaO_3$single crystals were grown under congruent melting composition having optical homogeneity. The curie temperature of the Fe:$LiTaO_3$crystal was increased with increased with increased doped Fe concentrations;by the ratio of $7.5^{\circ}C$ increase per Fe 0.1 wt%. Also, the optical transmittance was about 78 %, which was sufficient for optical device.

• Journal of Nutrition and Health
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• v.37 no.3
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• pp.176-181
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• 2004

This study was designed to investigate the effects of buthanol (BuOH) fraction of pine (Pinus densiflora Sieb et Zucc) needle on cholesterol and lipofuscin (LF) accumulations, acetylcholine (ACh) and its related enzyme activities such as choline acetyltransferase (CAhT) and acetylcholinesterase (AChE), and monoamone oxidase-B (MAO-B) activity, which destroyed the catecholamine-related neurotransmitters in brain membranes of Sprague-Dawley (SD) rats. Male SD rats were fed basic diets (control group) or experimental diets (BuOH-25, BuOH-50 and BuOH-100) for 45 days. Cholesterol accumulations in mitochondria and microsomes were significantly inhibited (about 14 - 17％ and 23 - 34％, respectvely) in BuOH-50 and BuOH-100 groups, whereas LF levels were significantly inhibited (about 10 - 14％) in BuOH-50 and BuOH-100 groups compared with control group. ACh levels and ChAT activities were significantly increased (about 11 - 17％ and 11 - 23％, respectively) in membranes of BuOH-50 and BuOH-100 groups compared with control group. AChE activities were significantly increased (about 14 - 17％) in membranes of BuOH-50 and BuOH-100 groups. There was no significant difference in MAO-B activities between control and experimental diet groups. The results suggest that butanol fraction of pine needle may play an effective role in an antiaging effect and improving a learning and memory impairments.

• Journal of The Korean Association For Science Education
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• v.21 no.1
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• pp.22-29
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• 2001

The purpose of this study is to investigate the effects of lessons adopting portfolio assessment regarding feedback on elementary school student's scientific knowledges, inquiry abilities and their perceptions of it. For this study, two classes of 5th grade elementary school in suburb were selected. As an experimental group, one class was selected to apply the lessons adopting portfolio assessment regarding feedback, and the other class as a control group was selected to apply the lessons adopting portfolio assessment without feedback. The investigator taught and assessed both group students. The results showed a significant difference in scientific knowledge between the experimental group and the control group (p<.05). More detailed analysis of scientific knowledge found that the feedback effect was statistically positive in the memory and the understanding domain, but there was no effect in the application domain. No statistical difference was identified in inquiry abilities. The results of the questionnaire on the perceptions of portfolio assessment showed that students of the experimental group had higher positive responses on the 'perception about the effects of lesson' and on the 'perception in scientific attitudes' than the control group. However, the control group students had higher positive responses on the 'perception about self-evaluate of their own portfolio' and the 'perception about need of feedback' than the experimental group.

• Journal of The Korean Association For Science Education
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• v.30 no.1
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• pp.170-180
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• 2010

Among the various fields of Earth Science, especially in Astronomy, we often deal with the change of space-time in an abstract way. Thus, making use of 'Concept Sketches'-simplified sketches that represent the main features, principles, processes and interrelationships of the learning content by using some concise explanations, signs and terms could help the students efficiently learn the phenomena of Astronomy. This study's aim was to check its effects and analyze the results of the lessons that included concept sketches and a discussion about the field of Earth Science in high school. The control group took traditional lessons, while the experimental group did a small-group discussion that used the concept sketches. After the lesson, some students were chosen to answer a questionnaire and go through an in-depth interview. The result of the data shows that the small-group discussion lesson that used the concept sketches helped both the high-ranking and low-ranking students to build concepts and was able to attract students' attention. Moreover, the students produced long-term memories of the content learned through the class discussion, which allowed them to exchange their own thoughts and opinions with other students. Most of all, drawing pictures, a familiar activity, appealed to the students, so they took part in the class eagerly.

• Journal of Life Science
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• v.28 no.11
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• pp.1386-1395
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• 2018

Over recent years, it has become evident that the central nervous system bidirectionally interacts with the gastrointestinal tract along the gut-brain axis. A series of preclinical studies indicate that the gut microbiota can modulate central nervous system function through a multitude of physiological functions. Polyphenols are ubiquitous plant chemicals included in foods such as fruits, vegetables, tea, coffee and wine, and their consumption is directly responsible for beneficial health effects due to antioxidant, anti-inflammatory, antimicrobial, immunomodulatory, anticancer, vasodilating, and prebiotic-like effects. There is increasing evidence that dietary polyphenol can contribute to beneficial effects in neuronal protection acting against oxidative stress and inflammatory injury as well as in cognitive functions. In this paper, we overview the neuroprotective role of dietary polyphenols especially focusing on the neuroinflammation and neurovascular function by interaction with the gut microbiome. Polyphenol metabolites could directly act as neurotransmitters crossing the blood-brain barrier and modulating the cerebrovascular system or indirectly modulating gut microbiota. In addition, evidence suggests that dietary polyphenols are effective in preventing and managing neurological disorders, such as age-related cognitive decline and neurodegeneration, through a multitude of physiological functions. Dietary polyphenols are increasingly envisaged as a potential nutraceuticals in the prevention and treatment of neurological disorders, because they possess the ability to reduce neuroinflammation, to improve memory and cognitive function and to modulate the gut microbiota.

• The Journal of the Convergence on Culture Technology
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• v.8 no.3
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• pp.291-296
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• 2022

This study was conducted on curcumin which had increased bioavailability as a potential AChE inhibitor for the treatment of neurodegenerative diseases. The purpose of this study is to confirm the in vitro neuroprotective effect on Aricumin (turmeric extract). To confirm the neuroprotective effect, AChE inhibition for Aricumin was evaluated, and cell viability was analyzed for HT-22cell, and oxidative stress (glutamate, H₂O₂)-induced HT-22 cytotoxicity was evaluated. As a result of the change in the AChE inhibition rate of Aricumin (Turmeric extract), it was confirmed that Aricumin at a concentration of 39.06㎍/ml or higher inhibited AChE activity by about 20% and more. And it was confirmed that the cytotoxicity of HT-22 cells induced by oxidative stress (Gluamate 5 mM and H₂O₂ 500 µM) was significantly inhibited from 0.01 to 0.1 mg/ml concentration (p<005). These results suggest that Aricumin (turmeric extract) have potential neuroprotective effects.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.250-257
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• 2023

Glutamate is an excitatory neurotransmitter distributed in the central nervous system of mammals. However, high concentrations of glutamate are known to cause neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and stroke by causing nerve cell death. In this study, the antioxidant activity and neuroprotective effect of subtropical natural products were analyzed. Among 11 subtropical plant extracts mainly tested, Sallacca wallichiana extract (SE) showed the greatest free radical scavenging activity. Then, we confirmed through WST-1 assay that SE protected HT22 cells against glutamate-induced cell death in a concentration-dependent manner. The protective effects of SE against glutamate-induced apoptosis in HT22 cells were also confirmed by flow cytometry analysis using Annexin V/PI double staining. We also confirmed using H₂DCF-DA single staining that SE inhibits glutamate-induced intracellular reactive oxygen species. And we were confirmed through that SE inhibited glutamate-induced phosphorylation of Mitogen-activated Protein kinases. Consequently, our results propose that SE may contribute to the development of therapeutics to prevent neurodegenerative diseases.

• The Journal of Korean society of community based occupational therapy
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• v.9 no.2
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• pp.23-31
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• 2019

Objective : The purpose of this study is to repeatedly conduct task-oriented training in scopolamine-induced dementia rats and as a result observe changes in the content of acetylcholine, a marker of cognitive function and central nervous system plasticity, to identify the improvement effect of dementia. Methods : It consisted of two groups. One group I was that did not perform task-oriented training in scopolamine-induced dementia rats and the other group II was that performed task-oriented training. Task-oriented training involved stretching, grasping and moving arms and walking obstacles on the legs. We performed a quantified passive avoidance test in the measurement of memory for cognitive function and compared the change in the content of acetylcholine for the plasticity of the central nervous system. Results : The results of the study are as follows: First, there was a significant improvement in cognitive function since the 4th days after task-oriented training of scopolamine-induced dementia rats(.00). Second, task-oriented training applied to scopolamine-induced dementia rats showed a significant increase in acetylcholine content. Conclusion : In this study, task-oriented training, which is often performed on senile dementia patients during occupational therapy intervention, was scientifically demonstrated in scopolamine-induced dementia rats by enhancement of cognitive function through memory improvement and increase in the content of acetylcholine confirming central nervous system plasticity.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2007.05a
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• pp.55-68
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• 2007

디자인 패턴은 새롭게 만들어 지는 것이 아니라 기존의 검증된 지식, 관용법, 원칙들을 체계화한 것이다. 다시 말하면 디자인 패턴은 특정한 문제를 해결하기 위한, 검증된 설계 방법에 이름을 붙인 것이다. 그러므로 적절한 디자인 패턴 사용은 1) 개발자들간의 원활한 의사소통에 도움을 주며, 2) 하급자가 고급기술을 쉽게 익힐 수 있도록 할 수 있다. 3) 또한 사용된 디자인이나 아키텍처를 재사용할 수 있도록 하고, 4) 만들어진 시스템의 유지 보수를 보다 쉽게 할 수 있는 등의 장점을 얻을 수 있다. 반면에 필요하지 않은 곳에 까지 디자인패턴을 사용하게 되면 소프트웨어를 복잡하고, 유지보수도 어렵게 만들 수 있다. 디자인 패턴의 분류는 수 많은 패턴을 비슷한 속성을 지닌 그룹들로 조직화 하는 것이다. 이는 개발자가 특정 문제에 맞는 디자인 패턴을 쉽게 선택 할 수 있도록 도와 줄 뿐만 아니라, 디자인 패턴의 주요특성을 빠르게 이해하고 간파 할 수 있게 한다. 그래서 Beck 이 디자인패턴을 소개한 이후 GoF, Buschmann, Grand, Antoy 등은 디자인 패턴을 단순히 열거를 통해 소개하지 않고, 각자의 기준에 따라 체계적으로 분류하여 패턴을 설명 하고 있다. 본 연구는 객체지향 설계의 근본 개념인 Polymorphism (Inclusion Polymorphism) 과 '객체 지향 소프트웨어 설계 원칙' 그리고 이 근본 원칙들이 UML 클래스 다이어그램에 나타나는 구조적 특정에 의거해 디자인 패 턴 해석을 수행 하였다. 본 연구의 목적은 1) 객체지향의 근본 원칙으로 표현 되는 패턴과 2) 설계자의 전문적 인 Art를 포함하고 있는 패턴으로 분류하는데 있다.3: 재미는 용이성을 통해 채택의도에 정의 영향을 미친다. 가설4: 유용성은 채택의도에 정의 영향을 미친다. 가설5: 용이성은 채택의도에 정의 영향을 미친다. 가설6: 용이성은 유용성에 정의 영향을 미친다. 본 연구의 대상은 자발적으로 이러닝을 채택할 수 있는 대학생을 대상으로 하였고, 설문 데이터 분석을 통한 실증연구를 수행하였다. 분석방법으로는 PLS 분석도구를 사용하였다. 분석결과 가설6을 제외하고는 모두 유용한 것으로 입증되었다.97)은 배움의 용이성, 기억의 용이성, 오류, 효율성, 만족성으로 분류하고 있고(Nielsen, 1997), Shneiderman(1998)는 효과성(직무시간, 배움의 시간), 효율성(기억의 지속시간, 오류), 만족도를 품질의 특성으로 분류하였다. 이와 같은 소프트웨어의 품질은 소프트웨어 계획, 개발, 성장과 쇠퇴의 모든 과정에 적용되며, 환경적 변화에 따라 사용자들의 정보욕구를 적절하게 반영하여 만족도를 높이 는 것이라고 요약할 수 있다. 그러나 현재까지 소프트웨어 품질 평가에 대한 연구들 은 보편적인 평가 항목들을 대상으로 측정하여 일반적인 품질기준을 제시하고 있고, 유사한 측정 내용들이 중복되어 있다. 이러한 경향은 산업별 특수성이 강한 소프트웨어에 대해서는 정확한 품질측정이 어려웠고, 품질측정에 대한 신뢰성을 떨어뜨리는 계기가 되었다. 이러한 한계를 극복하고자 나타난 방법론이 최종사용자들의 요구사항을 얼마나 적절하게 시스템에 반영했는지에 대한 사용성(Usability) 측정이다. 사용성에 대한 정의는 사용자들이 실질적으로 일하는 장소에서 직접 사용자들의 시스템 운용실태를 파악하여 문제점을 개선하는 것으로 요약할 수 있다. ISO9124-1

• Journal of Convergence for Information Technology
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• v.8 no.5
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• pp.77-83
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• 2018

A modular robot that memorizes motion can be easily created and operated because it expresses by hand. However, since there is not enough storage space in the module to store the user-created operation, it is impossible to reuse the created operation, and when the modular robot again memorizes the operation, it changes to another operation. There is no main controller capable of operating a plurality of modular robots at the same time, and thus there is a disadvantage that the user must input directly to the modular robot. To overcome these disadvantages, a remote controller has been proposed that can be operated in the surrounding smart devices by designing web server and component based software using wired and wireless network. In the proposed method, various types of structures are created by connecting to a modular robot, and the reconstructed operation is performed again after storing, and the usefulness is confirmed by regenerating the stored operation effectively. In addition, the reliability of the downloaded trajectory data is verified by analyzing the difference between the trajectory data and the actual trajectory. In the future, the trajectory stored in the remote controller will be standardized using the artificial intelligence technique, so that the operation of the modular robot will be easily implemented.