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Preparation of PEDOT-TiO2 Composite Thin Film by Using Simultaneous Vapor Phase Polymerization (동시-기상중합법을 이용한 Poly(3,4-ethylenedioxythiophene)(PEDOT)-TiO2 하이브리드 박막 제조)

  • Ko, Young Soo;Han, Yong-Hyeon;Yim, Jin-Heong
    • Polymer(Korea)
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    • v.38 no.4
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    • pp.525-529
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    • 2014
  • PEDOT-$TiO_2$ hybrid conductive thin film including semiconductive metal oxide was successfully prepared via simultaneous vapor phase polymerization (VPP). The mechanical properties such as pencil hardness and anti-scratch property as well as optoelectrical properties of PEDOT-$TiO_2$ hybrid thin film could be improved as compared with pristine PEDOT thin film. Physicochemically stable crosslinked $TiO_2$ layer derived from a sol-gel process by FTS was generated in the PEDOT thin film layer by simultaneous VPP, resulting in improving mechanical properties of the hybrid thin films without any deterioration of their original optoelectrical properties. PEDOT-$TiO_2$ hybrid thin film showed better electrical conductivity as compared with PEDOT film. It might be due to the fact that the surface morphology of hybrid thin film prepared by simultaneous VPP showed smoother than that of pristine PEDOT thin film.

A Study on the Development of Programming Education Model Applying English Subject in Elementary School (초등학교 영어교과를 적용한 프로그래밍 교육 모델 개발)

  • Heo, Miyun;Kim, Kapsu
    • Journal of The Korean Association of Information Education
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    • v.21 no.5
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    • pp.497-507
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    • 2017
  • Research on software education and linking and convergence of other subjects has been mainly focused on mathematics and science subjects. The dissatisfaction of various preferences and types of learning personality cause to learning gap. In addition, it is not desirable considering the solution of various fusion problems that can apply the computational thinking. In this way, it is possible to embrace the diverse tendencies and preferences of students through the linkage with the English subject, which is a linguistic approach that deviates from the existing mathematical and scientific approach. By combining similarities in the process of learning a new language of English education and software education. For this purpose, based on the analysis of teaching - learning model of elementary English subject and software education, we developed a class model by modifying existing English subject and software teaching - learning model to be suitable for linkage. Then, the learning elements applicable to software education were extracted from the contents of elementary school English curriculum, and a program applied to the developed classroom model was designed and the practical application method of learning was searched.

Analysis of Learners' Preferences in SW Education Contents Development (SW교육 콘텐츠 개발의 학습자 선호 분석)

  • Park, SunJu
    • Journal of The Korean Association of Information Education
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    • v.21 no.6
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    • pp.691-699
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    • 2017
  • Along with the increased significance of SW education in the 2015 revision curriculum, SW education using various educational methods and tools is being performed, and teaching and learning contents using SW education tools are continuously being developed. In this paper, we analyzed pre-service teachers' EPL contents preference types, preferred development subjects, and their relationship with pre-service teachers based on the analysis conducted after their EPL class session in which its results were assortatively analyzed by department, letter grade, and type. The result signified a clear difference in development subject and types among the departments, and it also showed a difference in development subject and its recipients among the types. However, there was no difference between development subject and type among the letter grade. This will provide a feedback on EPL classes and help develop EPL-related curricula as well as its application.

Effect of Execution Time-oriented the Elementary EPL Education on Computational Thinking Ability of Elementary School Students (수행시간 중심의 초등 EPL 교육이 초등학생 컴퓨팅 사고력에 미치는 효과)

  • Moon, Woojong;Boo, YongHo;Kim, Jonghoon
    • Journal of The Korean Association of Information Education
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    • v.24 no.3
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    • pp.233-241
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    • 2020
  • This study has developed and applied an elementary EPL education program centered on execution time as an educational method for improving Computational thinking of elementary school students, and then its effect has been verified. The education program was developed based on the results of preliminary demand analysis conducted on 48 elementary school students. In order to verify the effectiveness of the education program, 25 students were asked to participate in the class of elementary school students on a seven hours for six days. Using the "Korea Bebras Challenge 2018", educational effects were analyzed through the results of pre- and post-mortem examinations, and the analysis showed that elementary EPL education centered on performance time was effective in improving computational thinking of elementary school students

Effects of the Aquatic Exercise Program on Body Fat, Skeletal Muscle Mass, Physical Fitness and Depression in Elderly Women (수중운동 프로그램이 여성노인의 체지방, 골격근량, 체력 및 우울에 미치는 효과)

  • Song, Min-Sun;Kim, Soo-Keun;Yoo, Yong-Kwon;Kim, Hee-Jung;Kim, Nam-Cho
    • Journal of Korean Biological Nursing Science
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    • v.13 no.3
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    • pp.276-282
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    • 2011
  • Purpose: The aim of the present study was to investigate the effects of a aquatic exercise program on body mass index, body fat percentage and skeletal muscle mass, physical fitness using SFT (senior fitness test) and depression in elderly women. Methods: This study included 59 elderly women. Aquatics exercise program was performed three times per week for 12 weeks using rating of perceived exertion and body mass index, body fat percentage, skeletal muscle mass, physical fitness and depression were measured before and after exercise program. Statistical analysis was performed using t-test. Results: Body mass index (p=.002) and body fat percentage (p=.021) were significantly decreased after aquatic exercise program. Chair stand (p=.009), 2 minute step test (p<.001), back scratch (p<.001), and chair sit and reach (p<.001) were significantly increased after the aquatic exercise program. But, there was no significant differences in the depression. Conclusion: It is suggested the aquatic exercise program may play a significant role in improving body fat and physical fitness in the elderly women. However, as well as aquatic exercise program, sustained encouragement are required to improve physical and psychological traits.

COMPARISON OF THE FRICTIONAL RESISTANCE BETWEEN NON-ION PLATED AND TiN ION PLATED TO THE ORTHODONTIC APPLIANCE (TiN피막 처리된 교정 장치물의 마찰 저항력에 관한 비교연구)

  • Jang, Si-Ho;Kwon, Oh-Won;Kim, Kyo-Han
    • The korean journal of orthodontics
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    • v.23 no.4 s.43
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    • pp.671-691
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    • 1993
  • To estimate the possibility in the application of TiN ion-plating to the orthodontic appliance, this study investigated frictional force and frictional coefficient between non-ionplated and TiN ion-plated to the orthodontic appliance. The obtained results were as follows : 1. For each group, the frictional force between metal bracket and arch wire in the wet condition was exhibited lower than that in the dry condition. 2. In the dry condition, the frictional force was lowest with fourth group, and it increased in the order of the 3rd, 1st, and 2nd group. Same situation happened in the wet condition. 3. Experimental results using ceramic & plastic bracket showed that group B was lower than group A, and group D was similar to group C. 4. The surface texture after experiment showed that the scratch due to a friction with bracket was observed in an arch wire of dry contition. Also the surface of bracket was rougher than before. 5. We observed that a specimen surface processed with the TiN ion plating was smoother than that of without the TiN ion plating. 6. The surface texture of a metal bracket and an arch wire in the wet condition was observed smoother than that in the dry condition. 7. In the dry condition, the friction coefficient of each specimen was very similar to each other, but in the wet condition, the friction coefficient of specimen processed with the TiN ion plating showed lower values.

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A Study on the Improvement of Oxidation and Corrosion Resistance of Stainless Steel by Sol-Gel Ceramic Coating (II); Effect on Oxidation and Corrosion REsistance of $CeO_2$ Stabilized Zirconia Thin Film (졸-겔 세라믹 코팅에 의한 스테인레스강의 내산화 및 내식성 향상에 관한 연구 (II);$CeO_2$ 안정화 지르코니아 박막의 내산화 및 내식성 효과)

  • 이재호;우일기;김병호
    • Journal of the Korean Ceramic Society
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    • v.32 no.1
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    • pp.95-105
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    • 1995
  • Ceria(CeO2) stabilized zirconia(CeSZ) sol was synthesized with zirconium n-butoxide Zr(OC4H9)4 and cerium nitrate hexahydrate Ce(NO3)3.6H2O as precursors and ethylacetoacetate(EAcAc) as a chelating agent under atmosphere. CeSZ films were deposited on AISI 304 stainless steel using the prepared polymeric sol by dipcoating and the coating characteristics were investigated by XRD, ellipsometry, scratch test and SEM. The CeSZ film began to crystallize from amorphous to tetragonal phase at 40$0^{\circ}C$ and it was not converted into monoclinic phase up to 100$0^{\circ}C$ by the addition of 16mol% CeO2 as a stabilizer which could suppress phase transformation of zirconia. The CeSZ films were prepared by varying the EAcAc contents and the cncentration of CeSZ sol and measured the thickness and refractive index. From these results, it was found that the EAcAc contents and concentration of CeSZ coating sol evidently affect the densification of CeSZ film. The CeSZ film coated with 0.4M CeSZ sol and heat-treated at $600^{\circ}C$ for 10min had thickness of 50nm and 17% porosity. The CeSZ film on 304 stainless steel effectively acted as a protective layer against oxidation up to 80$0^{\circ}C$ and had superior corrosion resistance in 25% H2SO4 solution for 4.5 hrs.

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Effects of 36 Weeks of Resistance Training on Body Composition, Fitness and Blood Lipid Profiles in the Obese Elderly (36주간 저항성 운동이 비만노인의 신체구성, 체력 및 혈중 지질에 미치는 영향)

  • So, Wi-Young;Song, Mi-Soon;Cho, Bi-Long;Park, Yeon-Hwan;Lim, Jae-Young;Kim, Seon-Ho;Song, Wook
    • Journal of Korean Public Health Nursing
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    • v.24 no.1
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    • pp.39-48
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    • 2010
  • Purpose: To examine the effects of a 36-week resistance training program on body composition, fitness and blood lipid profiles in the obese elderly. Method: fourteen subjects were assigned into the resistance training group. The 12-16 exercise sessions were performed for 60min with 15-25 repetitions twice per week for 36 weeks. Data were analyzed by paired t-test with SPSS version 12.0 for Windows. Results: Significant changes were evident in weight (t=5.983, p<.001), body mass index (t=5.922, p<.001), % body fat (t=3.480, p=.004), and fat free mass (t=-2.592, p=.022). Concerning exercises, no significance was noted for back scratch (t=-1.814, p=.093), but were for 2-min step (t=-3.075, p=.009), arm curl (t=-2.223, p=.045), chair stand (t=-3.671, p=.003), chair sit and reach (t=-2.508, p=.026), and 8-ft up and go (t=5.545, p<.001). No significant changes were evident in total cholesterol (t=1.189, p=.279), and total glucose (t=0.689, p=.517), while the change in high-density lipoprotein was significant (t=3.535, p=.012). Conclusion: The 36-week resistance training program enhanced body composition and physical fitness, but not blood lipid profiles in obese elderly subjects.

Friction and Wear Characteristics of Plasma Coated Surface of Casting Aluminum Alloy (플라즈마 코팅한 주조용 알루미늄합금의 마찰 및 마멸특성)

  • Chae, Young-Hun;Ren, Jing-Ri;Park, Jun-Mock;Kim, Seock-Sam
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.5
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    • pp.791-799
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    • 1997
  • The wear characteristics and wear mechanisms of plasma sprayed Al/sub 2/ O/sub 3/-40%TiO/sub 2/ and Cr/sub 2/O/sub 3/ deposited on casting aluminum alloy(AC4C) were investigated. Specimens were processed for various coating thicknesses. Ball on disk type wear tester was used for wear test. The scratch test on plasma sprayed coating surface showed that critical load to break the coating layer was greater than 40 N. The critical load increase with the increase of coating thickness of specimens. The friction coefficient of Cr/sub 2/O/sub 3/ coating layer was less than that of Al/sub 2/O/sub 3/-40%TiO/sub 2/ coating layer. The wear resistance of Cr/sub 2/O/sub 3/ coating layer was greater than that of Al/sub 2/O/sub 3/-40%TiO/sub 2/ coating layer. Microscopic observation of worn surfaces was made by SEM. SEM observation showed that the main mechanism of wear for Al/sub 2/O/sub 3/-40%TiO/sub 2/ coating layer was abrasive wear under 50 N. For the case of Al/sub 2/O/sub 3/-40%TiO/sub 2/ coating layer, as the surface cracks perpendicular to sliding direction propagated, the wear debris was generated in wear track. However, the main mechanism of wear for Cr/sub 2/O/sub 3/ coating layer was brittle fracture under 150 N.

Antipruritic Effects of Ethanol Extracts from Perillae Japonicae Semen leaves and Chaenomelis Fructus (임자잎과 모과 에탄올 추출물의 피부 가려움증 억제 효과)

  • Kim, Hyeon-Soo;Jeon, In-Hwa;Mok, Ji-Ye;Kang, Hyun-Ju;Jang, Seon-Il
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.3
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    • pp.314-319
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    • 2012
  • Itching is one of the major diagnostic criteria of atopic dermatitis (AD) and one of its most troublesome symptoms that provokes the desire to scratch. Effective control of itching is believed to be one of the basic approaches in controlling AD. The purpose of this study was undertaken to investigate the antipruritic effect of ethanol extracts from Perillae Japonicae Semen leaves (PJSL) and Chaenomelis Fructus (CF) on the scratching behavior induced by pruritogen such as compound 48/80 or substance P in hairless mice. PJSL or CF treatment inhibited histamine release in HMC-1 stimulated compound 48/80 or substance P in a dose-dependant manner. In particularly, co-treatment PJSL ($50{\mu}g/mL$) plus CF ($100{\mu}g/mL$) significantly inhibited histamine release in HMC-1 stimulated compound 48/80 or substance P. PJSL, CF or PJSL plus CF was administered orally for 2 h and then compound 48/80 ($50{\mu}g/site$) or substance P ($100{\mu}g/site$) was injected into rostral back, and scratching of the injected site by the hind paw was counted for 1 h. PJSL or CF administration reduced the scratching behavior induced by compound 48/80 as well as substance P in a dose-dependent manner. Furthermore, co-administration of PJSL and CF markedly suppressed the scratching behavior induced by compound 48/80 as well as substance P. These suppressive effects were synergistically increased by their combination. From the preliminary observations, we considered that ethanol extracts from PJSL and CF could be an effective natural materials for itching treatment.