• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 전력전자학술대회
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• pp.57-59
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• 2018

This paper presents a novel reference variable speed control scheme of a BLDC motor for the high-speed blender machine according to the current limit. Because of a pulsating load variation of a high-speed blender machine, the actual speed is pulsated by the current limit in the high-speed region. The proposed control scheme uses a variable reference speed to reduce the speed variation from the current limit in the constant power region. The pulsated load is occurred at the material crushing, then the pulsated load is reduced after grinding. The reference speed is smoothly reduced at the pulsated load variation, then the enough torque can make a constant speed during crushing. When the pulsating load is reduced, the reference speed is automatically increased to the original speed value. The proposed control scheme is verified by experimental result by practical blender machine.

• Transactions on Electrical and Electronic Materials
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• 제2권3호
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• pp.7-11
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• 2001

Utility boiler operators seeking to gain the greatest economic advantage from their units are faced with three challenges, namely the obligatory light-up fuel costs, the additional expense of supplementary fuel firing should they wish to use a cheaper fuel that may be beyond the original burner manufacturer’s stability and combustion performance assurances and the immediate environmental impact of both. The novel use of plasma arc technology can provide a solution to these challenges. This paper introduces the work being undertaken through a joint collaboration between the EU, Kazahkstan and Russia in order to develop a tried and tested engineering methodology and a mathematical based application and sensitivity analysis approach for the design and optimisation stage of these plasma devices that, as a consequence, their assist in their universal introduction.

• 경영과정보연구
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• 제11권
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• pp.23-43
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• 2002

It is concentrated their efforts on expanding establishment mind like creating regular subject about establishment business of students and establishment business supporting center in University. Students creation enterprise club for establishment business with this hot wind of change and it seems to be success with hot wind of venture creation and gather many students for it. But practical result of research says that there are many problems like absence of education program, insufficient of professional leader, missing exact purpose so members decreased and activity itself piled up. Also creation business supporting system for student didn't conveyed to students evenly and effectively as much as original purpose and feeling effect is short of expectation. Therefore it will be required to reorganize supporting system and operate existed club to raise their ability of basic quality and gift that needs to do company activity and create basic mind about principal of free enterprise through activity of establishment enterprise by students. And we have to interest in their activity for creation enterprise with exact consciousness of purpose and prepare systematic, material, human supporting system that needs to establish enterprise with our knowledge and ability.

• Structural Engineering and Mechanics
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• 제61권1호
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• pp.49-63
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• 2017

This paper presents an original hyperbolic (first present model) and parabolic (second present model) shear and normal deformation theory for the bending analysis to account for the effect of thickness stretching in functionally graded sandwich plates. Indeed, the number of unknown functions involved in these presents theories is only five, as opposed to six or even greater numbers in the case of other shear and normal deformation theories. The present theory accounts for both shear deformation and thickness stretching effects by a hyperbolic variation of ail displacements across the thickness and satisfies the stress-free boundary conditions on the upper and lower surfaces of the plate without requiring any shear correction factor. It is evident from the present analyses; the thickness stretching effect is more pronounced for thick plates and it needs to be taken into consideration in more physically realistic simulations. The numerical results are compared with 3D exact solution, quasi-3-dimensional solutions and with other higher-order shear deformation theories, and the superiority of the present theory can be noticed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.289-294
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• 2002

Sand Compaction Pile (SCP) method, which uses sand material, is frequently used in Korea. However, the use of sand for SCP faces environmental and economical problems with the shortage of its resources. Therefore, it is necessary to substitute other materials for compaction piles. One of the alternatives is using gravel in lieu of sand. Granular Pile, constituted with sand and crushed-stone, is one of the methods to improve soft clay and loose sandy ground. In this study, modeled pile load tests are performed in test cell. The observations are made on the consolidation and the variation of water table of three different grounds, original, sand pile installed, and granular pile installed ground. In addition, engineering characteristics such as bearing capacity, settlement and drainage are investigated. The test results show that Gravel Compaction Pile (GCP) is more efficient for increasing bearing capacity and reducing settlement than SCP and had similar pore water pressure dissipation to sand. Therefore, the results show that GCP can be a good substitution for SCP.

• 동굴
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• 제78호
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• pp.1-8
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• 2007

The combination of mechano-chemical activation (MCA)and Self-propagating High-temperature Synthesis (SHS) has widened the technical possibilities for both methods. For YBCO systems the investigation showed that a short-term MCA of initial powders before SHS leads to single-phase and ultra-fine products. A new technique for preparation ultra-fine high-temperature superconductors (HTS) of YBCO composition with a grain size d <1m is developed using combination of MCA and SHS. The specific feature of the technique is formation of the $YBa_2Cu_3O_7-$ crystalline lattice directly from an X-ray amorphous state arising as a result of mechanical activation of the original oxide mixture. The technique allows the stage of formation of any intermediate reaction products to be ruled out. X-ray and magnetic studies of ultra-fine high temperature superconductors are carried out. Dimension effects associated with the microstructure peculiarities are revealed. A considerable enhancement of inter-grain critical currents is found to take place in the ultra-fine samples.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권6호
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• pp.374-376
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• 2019

Last week, after our receiving online journal regarding Journal of the Korean Association of Oral and Maxillofacial Surgeons, we found a recently published original article by Alawode et al., entitled "A comparative study of immediate wound healing complications following cleft lip repair using either absorbable or non-absorbable skin sutures". Although this clinical article was well written and provided a great deal of information regarding the suture materials in the cleft lip repair, I would like to add a few additional comments based on the importance of skin suture during cheiloplasties in the primary cleft lip or secondary revision patients with representative figures.

• 한국시조학회지:시조학논총
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• 제19권1호
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• pp.37-62
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• 2003

이 논문은 시조문화 정보 시스템 개발의 가능성과 전망을 논한 것이다. 본문의 내용을 요약하여 제시하면 다음과 같다. 1. 언어 자료로서의 시조 문화 정보 시스템은 원전 자료를 포함한 자료의 입력ㆍ교정 작업이 우선 필요하다. 2. 구축된 원시 자료를 가공할 때에는 TEI (Text Encoding Initiative), 시소러스(Thesauras) 등의 작업이 고려되어야 한다. 3. 이는 Topic Map을 구축하는 기본 작업이 된다. 4. 예술 자료로서의 시조 문화 정보 시스템은 다른 자료들 - 이미지, 동영상 등 -과의 연결(link)이 매우 중요하다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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• pp.96-99
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• 2004

The combination of mechano-chemical activation and Self-propagating High-temperature Synthesis (SHS) has widened the possibilities for both methods. For YBCO systems the investigation showed that a short-term mechano-chemical activation of initial powders before SHS leads to single-phase and ultra-fine products. A new technique for preparation ultra-fine high-temperature superconductors of YBCO composition with a grain size d ＜1 ${\mu}{\textrm}{m}$ is developed. The specific feature of the technique is formation of the YBa$_2$Cu$_3$O$_{7-{\delta}}$ crystalline lattice directly from an X-ray amorphous state arising as a result of mechanical activation of the original oxide mixture. The technique allows the stage of formation of any intermediate reaction products to be ruled out. X-ray and magnetic studies of ultra-fine high temperature superconductors (HTS) are carried out. Dimension effects associated with the microstructure peculiarities are revealed. A considerable enhancement of inter-grain critical currents is found to take place in the ultra-fine samples.fine samples.

• Transactions on Electrical and Electronic Materials
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• 제17권4호
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• pp.231-234
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• 2016

The AC insulation breakdown voltage was investigated for seven types of winding coils made of polyamideimide (PAI), flexural PAI (nanosilica 5 wt%) and anti-corona PAI (nanosilica 15 wt%) wires with various winding coil diameters of φ5, φ15 and φ25 mm. The winding coil was made of enameled wire with an enamel thickness of 30~50 μm, and the rectangular copper wire had a thickness of 0.77~ to 0.83 mm and width of 1.17~ to 1.23 mm, respectively. The insulation breakdown voltages of the original PAI coils with diameters of φ5, φ15 and φ25 mm were 7.30, 6.58, and 5.95 kV, respectively, and those values decreased as the winding coil diameter increased, regardless of the wire types.