• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.457-457
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• 2011

단일벽 탄소나노튜브(SWNTs)는 직경 및 키랄(chiral)특성에 따라 반도체성 튜브와 금속성 튜브로 구분되며, 작은 직경의 SWNTs는 큰 직경의 튜브에 비하여 일반적으로 기계적 특성이 뛰어나다고 알려져 있다. 따라서, 합성하는 단계에서 SWNTs의 직경 및 chiral 특성의 제어가 가능 하게 된다면 전자소자로의 응용을 한층 앞당길 수 있을 것으로 예상하고 있다. 이와 더불어 SWNTs의 수평배향성장은 SWNTs의 집적(integration)을 용이하게 할 수 있기 때문에 향후 나노전자소자 개발을 목표로 최근 많은 연구결과들이 보고되고 있다. 하지만 현재는 SWNTs가 고밀도로 합성되기 때문에, 우수한 개별 (individual) SWNT의 전기적 특성보다는 집단적(ensemble) 특성을 얻고 있다. 따라서, 합성기판 위에서 개별적인 SWNT를 낮은 밀도로 수평배향 성장하는 일은 향후 나노튜브기반의 고성능 전자소자 개발에 중요한 과제이다. 나아가, 수평배향 성장 된 개별 SWNT의 직경 및 키랄 특성까지 함께 제어할 수 있다면 곧바로 응용에 적용할 수 있는 획기적인 기술이 될 것이다. 본 연구에서는, SWNTs의 수평배향도 및 직경을 제어하여 성장시키는 것을 목표로 하였다. 합성기판은 퀄츠를 이용하였고, 합성촉매로는 나노입자의 밀도를 비교적 쉽게 제어할 수 있고, 균일한 크기를 갖는 페리틴 단백질을 이용하였다. 단분산(monodispersion) 된 촉매 나노입자를 얻기 위해서 스핀코팅 조건과 페리틴 용액농도를 조절하여 퀄츠기판 위에 분산시킨 후, 아르곤 분위기 하에 열처리를 통하여 촉매 나노입자의 크기 감소를 유도하였다. 그 결과 열처리 시간이 증가함에 따라 촉매 나노입자의 크기가 감소하는 것을 알 수 있었고, SWNTs의 직경 또한 감소하는 것을 확인하였다. 또한 퀄츠기판 위에 직경제어 합성 된 수평배향 SWNTs를 다른 기판으로 전사하는 기술을 확립함으로써, 향후 SWNTs기반의 소자 제작기술의 바탕을 마련하였다.

• Journal of Korean Home Economics Education Association
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• v.15 no.4
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• pp.55-66
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• 2003

This paper is a comprehensive study on how the family´s psychological environment affects juveniles in this ever-changing modern society by conducting a survey on teenagers living in Jinju, southern part of Korea. The survey was conducted on 402 students in Junior high schools in the Jinju city. The results are as follows. 1. On the students satisfaction with his/her families psychological environment, the respondents gave 3.5 points of the perfect 5. With regard to social. demographical and individual factors that affect their family lives, most of the teenagers pointed to economic power and self-esteem. 2. When asked how well they adapt to their school lives. the teenagers save 3.31 points out of 5. On social, demographical and individual factors that affect their school lives, the respondents mentioned gender economic power, a monthly allowance, mothers job and self-esteem. 3. The family´s psychological environment of adolescent was shown to be the most important factor on their school life.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.569-577
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• 1996

This experiment was conducted to investigate the effects of water potential by PEG treatment on germination and quantitative changes of seed storage reserves of soybean [Glycine max (L.) Merr.], peanut(Arachjs hypogaea L.) and corn(Zea may L.). Water potential of PEG(M.W. 10, 000) solution as germination media was 0.0, -0.2, and -0.5MPa. The highest moisture uptake rate was found in soybean seedlings among three crops. Moisture content of seedlings of three crops was decreased at -0.5MPa treatment and seedling length was delayed with water potential decrement. As water potential decreased, decreasing rate of protein content of the seedlings compared to seeds was declined in soybean and peanut. Decreasing rate of starch content of the seedlings was decreased in corn at -0.5MPa treatment. Increasing rate of sugar content of the seedlings was markedly decreased at -0.5MPa treatment in all crops. The results of this experiment showed that availability of moisture and synthesis of sugar for seed germination were influenced below -0.5MPa water potential in three crops.

• Korean journal of applied entomology
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• v.26 no.3 s.72
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• pp.117-122
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• 1987

Insect visitors of peach and plum blossoms and their activities were observed from Apr. 1 to Apr. 30, 1987 in the orchard of Gyeongsang National University, Jinju, Gyeongnam. A total of 22 species of 22 genera from 18 families and 4 orders, and 20 species of 20 genera from 14 families and 4 orders were collected on peach and plum blossoms, respectively. The most number of insects visited flowers around 11 a.m. or around 2 p.m., depending on weather. Most of the species and numbers were collected at the time of 80%-blooming in peach tree but no distinct trend was observed in plum tree.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.2
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• pp.260-267
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• 2016

The Internet has brought lots of changes to us sharing information mutually. However, as all social symptom have double-sided character, it has serious social problem. Vicious users have been taking advantage of anonymity on the Internet, stating comments aggressively for defamation, personal attacks, privacy violation and more. Malicious comments on the Internet are creating the biggest problem regarding unlawful acts and insults which occur on the Internet. In order to solve the issues, several studies have been done to efficiently manage the comments. However, there are limitations to recognize modified malicious vocabulary in previous research. So, in this paper, we propose a malicious comments detection technique by improving limitation of previous studies. The experimental result has shown accuracy of 87.8% providing higher accuracy as compared to previous studies done.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.227-234
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• 2006

The comparison of Corylopsis coreana populations between natural groups and deforestation groups is carried in five regions such as Seungju, Woldeung, Hwangjeon in Suncheon, Myeongseok in Jinju and Mt. Baegun in Pocheon. The number of sprouting per both $100m^2$ and each individual stump were appeared more in deforestation than in natural groups. In contrast, the height and the diameter of individuals by the number of sprouting are higher and larger in the natural groups. The relationship between the floristic composition and vegetation in the two groups of C. coreana populations was not appeared. Corylopsis coreana are propagated sprouting as well as seedling in deforestation groups located an opening area. Because of the powerful environmental adaptability through growth of the sprouting and the seedling in deforestation groups, the population of C. coreana are not extinction of species oneself, and on the contrary are showed expansion of C. coreana population after temporary disturbance.

• Journal of Digital Convergence
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• v.18 no.4
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• pp.341-346
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• 2020

Polymethyl methacrylate (PMMA), a self-curing resin mainly used in removable orthodontic appliances, is an acrylic resin mainly used in the field of modern dentistry. As an advantage, it has been used for a long time as a material for orthodontic devices in dentistry due to its color and volume, tissue affinity, and stability. The production of PMMA can be divided into self-polymerization method and thermal polymerization method according to activation method. Self-curing resins have long been used as orthodontic devices. The resin injection method is largely divided into a sprinkle-on method and a mixing method. In this study, we intend to test the mechanical properties according to the resin injection method of the orthodontic device, such as strength, modulus of elasticity, and surface roughness. There was no significant difference in strength as a result of three-point bending strength test on rectangular specimens (1.4 × 3.0 × 19.0 mm) of orthodontic PMMA. There was also no significant difference in hardness. There was no significant difference in surface roughness. It was confirmed that the orthodontic PMMA had no significant difference in mechanical properties according to the resin injection method of the orthodontic device.

• Aerospace Engineering and Technology
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• v.12 no.1
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• pp.32-39
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• 2013

All spacecraft components shall be checked for compatibility with vacuum using CVCM and TML in advance. CVCM and TML of the PZT-5 piezoelectric vibrator has to be less than 0.1% and 1.0% respectively. Also, it has less than $500ng/cm^2/hr$ of TQCM for vacuum bake-out test using high temperature and high vacuum. Thus, the piezoelectric vibrator may be employed in the vacuum environments. Finally, it can be confirmed that the characteristics change of the piezoelectric vibrator is less than 1% under vacuum environments. Also, the temperature dependency of the characteristics in the PZT-5 piezoelectric vibrator with the lateral mode was investigated in the range of $-100^{\circ}C$ to $90^{\circ}C$ using the thermal vacuum chamber to utilize the vibrator to the aerospace industries. As the results, at room temperature, the resonant and anti-resonant frequencies had the minimum value, whereas, the dielectric constant increased linearly from about 2500 to 7500 in the given temperature range. The mechanical loss decreased linearly from 0.08 to 0.03.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1623-1629
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• 2016

White breads containing Korean blue mussel (Mytilus edulis) powder were prepared and characterized. WB (white bread without blue mussel) and four different MBs (white breads containing blue mussel; number in front of MB means added % of blue mussel powder per wheat flour) were prepared by the straight dough method. With addition of blue mussel to bread, lightness decreased, whereas redness and yellowness increased. Addition of blue mussel did not significantly affect specific volumes of breads. DPPH and ABTS radical scavenging activities significantly increased with increasing blue mussel content. Addition of blue mussel to breads also increased alcohol dehydrogenase and acetaldehyde dehydrogenase activities. In the sensory test, 1MB acquired relatively high points for taste, flavor, texture, and preference. The results indicate that blue mussel can be applied to white bread to improve physiological functions without reduction of physicochemical characteristics.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.2
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• pp.282-289
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• 2008

To improve the efficiency of PDP TV, it should minimize the power losses transpired during AC-to-DC power conversion and PDP driving process. Generally the input power supply for PDP driving employes a two-stage power factor corrected converter, and it needs additional DC-to-DC converters to supply driving power for reset circuit ed sustain driver, which has high power consumption. However, such a circuit configuration has a difficulty for the PDP market requires low cost. To alleviate this problem, a new circuit composition is presented. It integrates input power supply with reset and sustain driver in a single power stack The input power supply of the proposed circuit has a single-stage structure to minimize power conversion loss, and it directly supplies power to the sustain driver so as to reduce the system size and cost.