• Korean Journal of Cleft Lip And Palate
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• v.10 no.1
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• pp.39-56
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• 2007

The bilateral cleft lip, a more severe form of clefting than unilateral cleft lip, involves separation of the lip along philtral lines, isolating the central segment (prolabium). Bilateral cleft lip may be either symmetrical or asymmetrical, in which case the cleft lip is split more on one side than on the other. The cleft affects the obvious facial form as an anatomic deformity and has functional consequences, affecting the child's ability to eat, speak, hear, and breathe. Although there would seem to be quite a variance in reported figures, ratios of cleft lip with or without cleft palate have gone as high as 1:500 and as low as 1:1000. It is known that less than 10% of cleft lips are bilateral. Although bilateral cleft lip is less common than unilateral cleft lip, the deformity is more severe, and the reconstructive technique is more complex. Surgery is the only treatment necessary for patients with bilateral cleft lip. Accompanying the evolution of surgical repair is the increasingly important role of orthodontic support with early presurgical alveolar and nasal molding. Repositioning the maxillary and alveolar segments into a more anatomic position allows the surgeon to repair the lip and associated nasal deformity under more optimal conditions. The purpose of this article is to review the related anatomy, presurgical management, and surgical management of bilateral cleft lip.

• Design & Manufacturing
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• v.11 no.3
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• pp.35-40
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• 2017

PCR(Polymerase chain reaction) is a technique to replicate and amplify a desired part of DNA. It is used in various aspects such as DNA fingerprint analysis and rare DNA amplification of an extinct animal. Especially in the medical diagnosis field, it provides various measurement methods at the molecular level such as genetic diagnosis, and is a basic tool for molecular diagnostics. The internal shape of the plastic vial tube for PCR analysis used in the DNA detection process, and the surface roughness and internal cleanliness can affect detection and discrimination results. The plastic vial tube demanded by the developer of the PCR analysis equipment should be changed to a structure that eliminates the residual washing solution in the washing process to ensure the internal cleanliness. Thus the internal structure and the internal surface design for improving the PCR amplification efficiency are key issues to develop the plastic vial tube for the DNA detection process.

• 대한공업교육학회지
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• v.31 no.2
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• pp.350-363
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• 2006

Recently, the micro end-milling processing is demanded the high-precise technique with good surface roughness and rapid time in milli-structure parts, micro machine parts and molding industry. The cutting conditions of micro end-milling has an effect on surface roughness of cutting surface. Therefore this study was carried out to cut stainless steel using high revolution air bearing spindle and micro end-mill and analyze the cutting condition to get the optimum surface roughness by design of experiment. From this study, surface roughness have an much effect according to priority on depth of cut, revolution of spindle and feed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.247-251
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• 2004

Chemical-Mechanical Polishing(CMP) especially is becoming one of the most important ULSI processes for the 0.25m generation and beyond. And there are many elements affecting CMP performance such as slurry, pad, process parameters and pad conditioning. Among these elements the CMP pad is considered one of the most important because of its change. But the surface of the pad has irregular pores, so there is non-uniformity of slurry flow and of contact area between wafer and the pad, and glazing occurs on the surface of the pad. So we make CMP pad with micro structure using micro molding method. This paper introduces the basic concept and fabrication technique of CMP pad with micro-structure and the characteristic of polishing. Experimental results demonstrate the removal rate, uniformity, and time vs. removal rate.

• Transactions of Materials Processing
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• v.12 no.7
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• pp.640-646
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• 2003

The nanoprobe based on lithography, mainly represented by SPM based technologies, has been recognized as potential application to fabricate the surface nanostructures because of its operational versatility and simplicity. The objective of the work is to suggest new mastless pattern fabrication technique using the combination of machining by nanoindenter and KOH wet etching. The scratch option of the nanoindenter is a very promising method for obtaining nanometer scale features on a large size specimen because it has a very wide working area and load range. Sample line patterns were machined on a silicon surface, which has a native oxide on it, by constant load scratch (CLS) of the Nanoindenter with a Berkovich diamond tip, and they were etched in KOH solutions to investigate chemical characteristics of the machined silicon surface. After the etching process, the convex structure was made because of masking effect of the affected layer generated by nano-scratch. On the basis of this fact, some line patterns with convex structures were fabricated. Achieved patterns can be used as a mold that will be used for mass production processes such as nanoimprint or PDMS molding process. All morphological data of scratch traces were scanned using atomic force microscope (AFM).

• Macromolecular Research
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• v.17 no.3
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• pp.192-196
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• 2009

Recently, the multi-screening of target materials has been made possible by the development of the surface plasmon resonance (SPR) imaging method. To adapt this method to biochemical analysis, the multi-patterning technology of protein microarrays is required. Among the different methods of fabricating protein microarrays, the microfluidic platform was selected due to its various advantages over other techniques. Microfluidic devices were designed and fabricated with polydimethylsiloxane (PDMS) by the replica molding method. These devices were designed to operate using only capillary force, without the need for additional flow control equipment. With these devices, multiple protein-patterned sensor surfaces were made, to support the two-dimensional detection of various protein-protein interactions with SPR. The fabrication technique of protein microarrays can be applied not only to SPR imaging, but also to other biochemical analyses.

• Advances in aircraft and spacecraft science
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• v.6 no.2
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• pp.105-116
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• 2019

An alternative to the multilayered preforming is to use structures reinforced through-the-thickness in order to manufacture thicker and more complex pieces. Stitching technology is developed to bind dry reinforcements together or to strengthen composites in thickness performance by inserting structural yarns. Tufting process represents the simplest one-sided sewing technology and it is specifically designed for dry preform/liquid composite molding process route. Currently, the tufting technology is getting more and more interest due to its simplest and efficient process where it involves the insertion of binder threads via a single needle through the fabric. This technique of reinforcement through-the-thickness requires only one access to the preform which makes it suitable for three-dimensional structures and complex shaped textile composites. This paper aims to improve the understanding of the mechanical performance of tufted structures. An experimental study was developed, which included tensile and bending behaviours of tufted and un-tufted preforms, in order to evaluate the effect of tufting on the mechanical performance of dry preforms. The influence of the process parameters (tufting density, loop length, tufting yarns${\ldots}$) on the mechanical performance ofthe final structure is also highlighted.

• Composites Research
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• v.31 no.6
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• pp.311-316
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• 2018

In the present study, the effect of GO in damping capacity of CF/epoxy laminates was studied via free vibration analysis. The composite laminates were manufactured by using vacuum assisted resin transfer molding technique. The damping properties of the prepared hybrid composites were determined in terms of natural frequency and damping ratio in free vibration test. The foremost aspire of this investigation was to compare the vibration properties i.e. natural frequency and modal damping of the prepared composites with the numerical results. The numerical study was carried out via FEA using $ANSYS^{TM}$ workbench software. The parametric study of the numerical models was also studied considering the beam free length and the beam thickness. It was found that the incorporation of GO enhanced the damping capacity of the composite and the variation of natural frequencies in mode1varied by 2-5% compared to the experimental study.

• Journal of the Korea Safety Management & Science
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• v.20 no.4
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• pp.1-6
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• 2018

Recently, bicycle has means of effective healthy transportation, and riding the bicycles is considered as popular recreational and sporting activities. Also, the saddle, steering system, driving device and braking device are researched briskly because of consumer's need for driving performance and comfort. Especially, the importance of a cassette responsible for transmission function by transmitting power to the drive shaft through the chain is very focused. The writer conducted structural analysis for the sprocket of each level using the ANSYS widely used for the analysis. Speed shifting performance was enhanced by minimization / simplification of shifting point through a sort of tooth profile of the cassette. By partitioning a clear value type and other shifting point, it has been modified to enable smooth speed-shifting. In addition, as titanium precision forming process, this study studied the molding technique by blanking and dies forging for mass production of the cassette. so it could be expected that the entire drive train would utilize that in the future. The stamping process capability for thin materials for the mass production of the sprockets is applicable to producing automobile parts, so lightweight component production is likely to be possible through that, for the safety of driving.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.4
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• pp.100-106
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• 2022

Topology optimization is applied for the optimal design of various products to ensure weight reduction and productivity improvement. Reducing the weight of the mold while maintaining its rigidity can ensure shortening of the production cycle, stabilization of the mold temperature, and reduction of mold material costs. In this study, a topology optimization technique was applied to the optimal design of the injection mold, and a topology-optimized model of the mold was obtained. First, the injection mold for the square specimens was modeled. Subsequently, a structural analysis was performed by implementing a load condition generated during the injection molding process. Topology optimization was performed based on the structural analysis results, and the models of the initial and topology-optimized designs were manufactured at 1/4 magnification using a 3D printer. Consequently, compared with the existing model, the weight of the topology-optimized model decreased by 9.8%, and the manufacturing time decreased by 7.61%.