• Structural Engineering and Mechanics
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• 제45권5호
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• pp.631-641
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• 2013

In this paper, the problem of axisymmetric deformation of the circular membrane fixed at its perimeter under the action of uniformly-distributed loads was resolved by exactly using power series method, and the solution of the problem was presented. An investigation into the so-called Hencky transformation was carried out, based on the solution presented here. The results obtained here indicate that the well-known Hencky solution is, without doubt, correct, but in the published papers the statement about its derivation is incorrect, and the so-called Hencky transformation is invalid and hence may not be extended to use as a general mathematical method.

• Journal of Mechanical Science and Technology
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• 제16권4호
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• pp.549-556
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• 2002

An investigation on the fully developed heat transfer and friction factor characteristics has been made in rectangular ducts with one-side roughened by five different shapes. The effects of rib shape geometries as well as Reynolds numbers are examined. The rib height-to-duct hydraulic diameter, pitch-to-height ratio, and aspect ratio of channel width to height are fixed at e/De=0.0476, P/e=8, and W/H=2.33, respectively. To understand the characteristics of heat transfer enhancements, the friction factors are also measured. The data indicates that the triangular type rib has a substantially higher heat transfer performance than any other ones.

• 한국농촌건축학회논문집
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• 제9권1호
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• pp.35-42
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• 2007

This study is the research of occupation distribution about citizen members of autonomy organization in Cheongju area. Investigation of autonomy organization members acting as local readers makes it possible to understand direction for community promotion. Result of this study sums up two type occupational categories. First, in urban area independently managers is above participation ratio in public affairs appeared. On the other hand, ratio of private organization, employee, and experts are low. In rural area, it shows the participation ratio of functional representatives and farmers highly. Second, with investigation of detailed occupation, most independent contractors and such as architecture, real-estate, whole and retail sales, restaurant, nursery, and private educational institute. And small number of insurance, news paper, car sales, gas station mangers participate in autonomy organization. Private organization consist of educational organization, social welfare corporate and district head council, as well as some teachers and farmers.

• 소성∙가공
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• 제10권5호
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• pp.396-401
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• 2001

The concept of the mixtures can be used not only in the composites but also in the materials with precipitates and matrix. In this investigation, the finite element method of axisymmetric unit cell models and the rule of mixtures of the Voigt and the Reuss models are used to analyze the overall mechanical response of composites with homogeneously distributed particles. The calculations have been cameo out by taking the materials as i) hardening and ii) perfect plastic materials. The Plastic properties are predicted for various volume fractions of the soft and hard particles. The computational results are compared with the results of the rule of mixtures. It is found that the plastic flow curves agree well with the Voigt model when the volume fraction of the particles is high. On the other hand, the calculated flow curves exist between the Voigt model and the Reuss model when the volume fraction of the particles is low.

• Safety and Health at Work
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• 제5권3호
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• pp.158-160
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• 2014

Investigation and analysis of accidents are critical elements of safety management. The over-riding purpose of an organization in carrying out an accident investigation is to prevent similar accidents, as well as seek a general improvement in the management of health and safety. Hundreds of workers have suffered injuries while installing, maintaining, or servicing machinery and equipment due to sudden re-energization of power lines. This study presents and analyzes two electrical accidents (1 fatal injury and 1 serious injury) that occurred because the power supply was reconnected inadvertently or by mistake.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.964-968
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• 2008

Infrared thermography using high-speed infrared camera has been recognized as a powerful method for various potential applications, such as nondestructive inspection, failure analysis, stress analysis, and medical fields, due to non-contact, high-speed, and high spatial resolution at various temperature ranges. In this investigation, damage evolution due to generation of hot spots on railway brake disc was investigated using the infrared thermography method. A high-speed infrared camera was used to measure the surface temperature of brake disc as well as for in-situ monitoring of hot spot evolution. From the thermographic images, the observed hot spots and thermal damage of railway brake disc during braking operation were qualitatively analyzed. Moreover, in this investigation, the previous experimental and theoretical studies on hot spots phenomenon were reviewed, and the current experimental results were introduced and compared with theoretical prediction.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2009년도 춘계학술대회 논문집
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• pp.1024-1028
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• 2009

Government imposed a duty to perform feasibility investigation on huge development projects which cost are higher than 50 million dollars on May 1999. This is to prevent waste of money occur from lack of review on huge public projects and raise the efficiency of government budget. Although maintenance and managing analysis method for public infrastructures are developed and proposed by other institutions as Korea Infrastructure Safety & Technology Corporation but it is not well applied on the aspect of the railway fixed time and costumer costs. Therefore a good point of quantitative and qualitative reference which fits railway character is need and following guidelines from the phase of feasibility study are need to prevent governments budget waste.

• Clinical and Experimental Pediatrics
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• 제53권9호
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• pp.824-829
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• 2010

The safety and effectiveness of colonoscopy in the investigation of lower gastrointestinal tract pathology in children has been established for more than 2 decades in Korea. The skill and experience have since advanced to the point that both diagnostic and therapeutic colonoscopy are now routinely performed by most pediatric gastroenterologists. Pediatric colonoscopy differs significantly from its adult parallels in nearly every aspect including patient and parent management and preparation, selection criteria for sedation and general anesthetic, bowel preparation, expected diagnoses, instrument selection, imperative for terminal ileal intubation, and requirement for biopsies from macroscopically normal mucosa. Investigation of inflammatory bowel disease, whether for diagnosis or follow-up evaluation, and suspected colonic polyps are the most common indication for pediatric colonoscopy. The child who presents with signs and symptoms of lower gastrointestinal disorder should undergo colonoscopy with biopsy to make the diagnosis, as well as to help determine the appropriate therapy. This review introduces practical information on pediatric colonoscopy, the author's experiences, and the role of colonoscopic examination in the diagnosis and treatment of pediatric lower gastrointestinal disorders.

• 한국분말재료학회지
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• 제9권4호
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• pp.211-217
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• 2002

It is well known that the powder injection molding(PIM) process can overcome the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of conventional casting. Increasing demands from industry for not only the dimensional accuracy nut mechanical strength in PIMed parts have had much effort focused on the investigation of mechanical properties of mechanical strength in PIMed parts have had much effort focused on the investigation of mechanical properties of sintered parts formed with high-strength metallic powders. The 17_4 PH $10\mu{m}$ were injection-molded into flat tensile specimens. Sintering of the compacts was carried out at the various temperatures ranging from 900 to $1350^{\circ}C$. Sintering behavior of the compacts and tensile properties of sintered specimens were investigated.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2006년도 추계공동학술대회
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• pp.437-450
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• 2006

The Contour Crafting(CC) process, which has been developed at the University of Southern California, aims at automated construction of whole houses as well as sub-components. For this purpose, new trowel mechanism is basically needed in order to fabricate the true 3D shape. This paper presents our concepts and initial investigation of 3D free form fabrication using the pivoting side trowel. Specifically, the status of research and development of the processand experiments with ceramics materials, and its potential application areas are detailed.