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The Influences of Quality Team Interaction on the Changes of Entrepreneurial Giftedness SelfEvaluated by Gifted Korean Adolescents Participating in a ProjectBased Entrepreneurship Education Program
Yoo Hyun Sil, Min-Jeong Baek 한국교육학회 교육학연구 25 Pages
한국교육학회 교육학연구 2021, 59권 3호 5 111-135 (25 pages)
to draw creative ideas through group work. Afterwards,patent writing and application activities follow with expert mentoring provided. Specifically,those gifted education programs are run based on team project-based learning, and the main goal of the education program is the ability to find and solve real-world problems, especially to look at rapidly changing social problems and practice finding... The aim of this study was to examine the influences of facilitative team interaction on the educational outcomes (self-evaluated entrepreneurial giftedness) of a project-based learning (PBL) program designed for entrepreneurial-gifted Korean adolescents. One-hundred thirty-one (131) gifted adolescents participated in the two-day PBL gifted program provided by KAIST. Self-evaluations of entrepreneurial giftedness for the basic and the advance course were collected before and after provision of... -
Carbon rich fly ash and their nanostructures
Numan Salah, Sami S. Habib, Zishan H. Khan, Ahmed Alshahrie, Adnan Memic, Attieh A. Al-ghamdi 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 3 23-31 (9 pages)
substrate to produce CNTs [14]. Nath and Sahajwalla [15] have reported on the application of fy ash as a catalyst for the synthesis of CNT ribbons. Silvestre-Albero and Rodriguez-Reinoso [16] have re- ported on the use of carbon materials for the adsorption of CO2 due to the presence of a large pore volume, high surface area and a rich surface chemistry. However, no efforts have been made to... Carbon rich fly ash was recently reported to have compositions that are ideal for use as a precursor and catalyst for carbon nanotube growth. This fly ash powder is mostly composed of pure carbon, predominantly present as sp2. In this work, the effect of sonication time on the morphology and structural properties of carbon rich fly ash particles is reported. The obtained results show that ultrasound treatment is an effective tool for producing ultrafine particles/fragments with higher porosity,... -
Phenylethynyl-terminated polyimide, exfoliated graphite nanoplatelets, and the composites: an overview
Donghwan Cho, Lawrence T. Drzal 한국탄소학회 Carbon Letters 11 Pages
한국탄소학회 Carbon Letters 2016, Vol.19 1 1-11 (11 pages)
R. Application of dynamic mechanical analysis for the study of the interfacial region in carbon fber/epoxy com- posite materials. Polym Compos, 14, 414 (1993). http://dx.doi. org/10.1002/pc.750140508. [44] Elmore JS, Stinchcomb WW. Proceedings of the 7th Annual Meet- ing Adhesion Society, Jacksonville, FL, 150 (1994). [45] Cho D, Choi Y, Drzal LT. Characterization, properties, and pro- cessing of... In efforts to characterize and understand the properties and processing of phenylethynyl-terminated imide (LaRC PETI-5, simply referred to as PETI-5) oligomers and polymers as a high-temperature sizing material for carbon fiber-reinforced polymer matrix composites, PETI-5 imidization and thermal curing behaviors have been extensively investigated based on the phenylethynyl end-group reaction. These studies are reviewed here. In addition, the use of PETI-5 to enhance interfacial adhesion between... -
Effects of cross-linking methods for polyethylene-based carbon fibers: review
Kwan-Woo Kim, Hye-Min Lee, Jeong-Hun An, Byoung-Suhk Kim, Byung-Gak Min, Shin-Jae Kang, Kay-Hyeok An, Byung-Joo Kim 한국탄소학회 Carbon Letters 24 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.3 2 147-170 (24 pages)
of LLDPE-based CFs on their strength and modulus, and these properties could be improved consid- erably by using thin precursor fibers. Thin LLDPE fila- ments were obtained by application of elevated spinline temperatures in the melt-spinning process, which led to an improvement of the maximum attainable draw-down ratio. Careful carbonization of these filaments gave 17 m thick CFs with a... In recent decades, there has been an increasing interest in the use of carbon fiber reinforced plastic (CFRP) in aerospace, renewable energy and other industries, due to its low weight and relatively good mechanical properties compared with traditional metals. However, due to the high cost of petroleum-based precursors and their associated processing costs, CF remains a specialty product and as such has been limited to use in high-end aerospace, sporting goods, automotive, and specialist... -
Preparation and characterization of carbon fiber-reinforced thermosetting composites: a review
Fan-Long Jin, Soo-Jin Park 한국탄소학회 Carbon Letters 11 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.2 1 67-77 (11 pages)
given matrix, the interface between the fber and the matrix will be controlled by the surface characteristics of the CFs. Consequently, surface treatments of CFs are essential to their practical application in CFRP composites. The various surface treatment methods that may be applied to CFs include wet chemical methods, dry chemical methods, electrochemical methods, plasma methods, and sizing... Carbon fibers (CFs) have a unique combination of properties which allow them to be widely used as reinforcing materials in advanced polymer composites. The mechanical properties of CF-reinforced polymer composites are governed mainly by the quality of interfacial adhesion between the CFs and the polymer matrix. Surface treatments of CFs are generally carried out to introduce chemical functional groups on the fiber surfaces, which provide the ability to control the surface characteristics of CFs.... -
Influence of hot-pressing pressure on the densification of short-carbon-fiber-reinforced, randomly oriented carbon/carbon composite
Thakur Sudesh Kumar Raunija and Sharad Chandra Sharma 한국탄소학회 Carbon Letters 9 Pages
한국탄소학회 Carbon Letters 2015, Vol.16 No.1 4 25-33 (9 pages)
of producing carbon/ carbon composite. Indian Patent, Application No. 1713/CHE/2012 (2012). [22] Ehrburger P, Dentzer J, Dziedzinl P. Pyrolysis of impregnated carbon adsorbents after exposure to cyanide gases. J Anal Appl Pyrolysis, 24, 333 (1993). http://dx.doi.org/10.1016/0165-2370 (93)85011-M. [23] Vix-Guterl C, Shah S, Dentzer J, Ehrburger P, Manocha LM, Pa- tel M, Manocha S. Carbon/carbon... The prime objective of this research was to study the influence of hot-pressing pressure and matrix-to-reinforcement ratio on the densification of short-carbon-fiber-reinforced, randomly oriented carbon/carbon-composite. Secondary objectives included determination of the physical and mechanical properties of the resulting composite. The ‘hybrid carbon-fiberreinforced mesophase-pitch-derived carbon-matrix’ composite was fabricated by hot pressing. During hot pressing, pressure was varied from 5... -
Method and mechanism of dispersing agent free dispersion of short carbon fibers in silicon carbide powder
Thakur Sudesh Kumar Raunija, Mariamma Mathew, Sharad Chandra Sharma 한국탄소학회 Carbon Letters 7 Pages
한국탄소학회 Carbon Letters 2014, Vol.15 No.3 4 180-186 (7 pages)
Wesley C. A process of producing carbon/ carbon composite. Indian Patent, Application No. 1713/CHE/2012 (2012). [6] Krenkel W, Berndt F. C/C-SiC composites for space applications and advanced friction systems. Mater Sci Eng A, 412, 177 (2005). http://dx.doi.org/10.1016/j.msea.2005.08.204. [7] Botelho EC, Silva RA, Pardini LC, Rezende MC. A review on the development and properties of continuous... This study highlights a novel method and mechanism for the rapid and effective milling of carbon fibers (CFs) in silicon carbide (SiC) powder, and also the dispersion of CFs in SiC powder. The composite powders were prepared by chopping and exfoliation of CFs, and ball milling of CFs and SiC powder in isopropyl alcohol. A wide range of CFs loading, from 10 to 50 vol%, was studied. The milling of CFs and SiC powder was checked by measuring the average particle size of the composite powders. The... -
Effects of Polymerization and Spinning Conditions on Mechanical Properties of PAN Precursor Fibers
Qi-feng Qin, Yong-qiang Dai, Kai Yi, L iZhang, Ryu Seung Kon, Ri- 한국탄소학회 Carbon Letters 8 Pages
한국탄소학회 Carbon Letters 2010, Vol.11 No.3 2 176-183 (8 pages)
2001-05-09. [6] Davidson, J. A.; Jung, H. T.; Hudson, S. D. Polymer 2000, 41, 3357. [7] Gupta, B. S.; Mogahzy, Y. E. J. Applied Polymer Science 1989, 38, 899. [8] Zhang, W. X.. Hi-Tech Fiber & Application 2001, 26, 12. [9] Japan Toray Co., Ltd. JP58-214520,1983-12-13. [10] Jin, R. G. Korea Xuanwen Media Market Press, 1994. [11] Jin, R. G. Heilongjiang Science and Technology Press, 1985. [12]... -
항공우주에 관련한 광학계 분야의 특허 출원동향 분석
표승준, 류시웅, Pyo. Seung-Jun, Ryu. Si-Ung 한국정밀공학회 한국정밀공학회지 6 Pages
한국정밀공학회 한국정밀공학회지 2007, Vol.24 No.2 7-12 (6 pages)
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Report on a case treated with lingual multibracket appliance
Hee-Moon Kyung 대한치과교정학회 The Korean Journal of Orthodontics 11 Pages
대한치과교정학회 The Korean Journal of Orthodontics 1996, 제 26권 제 6호 6 705-715 (11 pages)
com pensation bend on the main archwire to prevent horizontal arid vertical bowing effects. The trans palatal bar and the face bow also can be used to reinforce the anchorage. However, the application of a J hook on the main archwire is not easy to use. A J hook usually can be used with a removable acrylic “Jig” on the maxillary anterior region. One of the most difficult things is the... The lingual multibracket appliance was developed to overcome the unesthetic nature of traditional fixed orthodontic labial appliances; however, treatment with this appliance was regarded as very difficult as well as a time-consuming. Recently, these problems have been reduced because of advances in lingual bracket systems, improved indirect bonding technique and the development of more flexible wires. There has been a marked increase in the number of adults desiring orthodontic treatment over...