• Korean Journal of Cleft Lip And Palate
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• v.15 no.2
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• pp.89-96
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• 2012

Le Fort 1 osteotomy or maxillary advancement with distraction osteogenesis (DO) is main treatment strategy for cleft palate patients with maxillary hypoplasia. Maxillary DO allows greater maxillary advancement within physiological limit than Le Fort 1 osteotomy. Moreover, it is better for velopharyngeal function. However, there is a greater tendency for an increase in nasal sound when maxilla is advanced excessively. Therefore, the advancement of anterior maxillary segment using DO has been utilized. It offers advantages such as an increase in the length of the palate, a prevention of the change in palatopharyngeal depth, and a preservation of the velopharyngeal function. Moreover, it will obliterate the necessity of bone graft, and it prevents the occurrence of oronasal or oroantral fistula. Finally, it stimulates the regeneration of the soft and hard tissue of alveolus, and subsequently makes possible to place implant.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.10
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• pp.1961-1970
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• 2002

A laser scanner is widely used fur a device fur acquiring point data in reverse engineering. It is more efficient to generate a surface automatically from the line-typed data than scattered data of points clouds. In the case of a compound model, it is hard to represent all the scanned data into one surface maintaining its original line characteristics. In this paper, a method is presented to generate a surface by the segmentation of measured point data. After forming triangular net, the segmentation is done by the user input such as the angle between triangles, the number of facets to be considered as small segment, and the angle for combining small segment. B-spline fitting is implemented to the point data in each segment. The surface generation through segmentation shows a reliable result when it is applied to the models with curvature deviation regions. An useful algorithm for surface reconstruction is developed and verified by applying an practical model and shows a good tools fur reverse engineering in design modification.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.329-330
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• 2003

In general, the thermoplastic elastomers have the elastic recovery property caused by phyical crosslinks after the stress is applied. Segmented block copolyetheresters also have been used as elastomers. Many$\^$l-2/ tried to improve the elastic recovery of those which are less elastic than polyurethane. We confirmed that the copolyetherester based on poly(2,6-butylene naphthalate)(PBN) ha.4 segment had the high melting temperature, whcih was useable at the broader temperature range and the one based on poly(1,3-trimethylene terephthalate)(PTT) the high crystallinity, which would be expected to get the high elastic recovery. (omitted)

• Asian Journal of Innovation and Policy
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• v.6 no.3
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• pp.332-353
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• 2017

This paper highlights how Thailand upgrades its positions in global value chains in high-tech, mid-tech and low-tech industries represented by electronics, automotive and frozen seafood, respectively. In the electronics industry, there are not many capable firms in the upstream segment like semiconductors. Nevertheless, transnational corporations in segment like hard disk drive began to invest in process R&D and collaborate more with local suppliers, universities and public research institutes in human resource and technological development. In the automotive industry, several Japanese car manufacturers such as Toyota, Honda, Nissan, and Isuzu set up R&D/Technical centres in Thailand since 2000s. This prompted Japanese and local part suppliers to also invest more in engineering, design and development activities. Some local universities offer as well engineering programmes specifically targeting the automotive industry. In the frozen seafood industry, several Thai firms have developed new ready-to-eat products, own brands and international distribution networks. They started to become transnational corporations investing in both developing and developed countries.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.261-262
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• 2003

Shape memory polyurethane (PU) with soft and hard segments has been extensively researched since its discovery by Mitsubishi in 1988 [1]. Hard segments can be formed via hydrogen bonding and crystallization, function as physical crosslinks below melting point (Tm). The reversible phase transformation of the soft segment is responsible for the shape memory effect. (omitted)

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.89-92
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• 2004

Precast Segmental method was developed in germany 1950's. This method has been adoptted in long span girder mainly owing to easy construction effect. But, so far, The limit exists that this method is constructed in a portion of span and hard conveyance and foundation. This study was performed to analysis behavior difference of two rectangular section girder, spliced girder that was jointed 5-sliced 0.8m segment and monolithic girder that was produced in one body 4m span.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.76-85
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• 2019

Recently, various investigation of vegetable oil which is extracted from natural resources is being progressed because of its low cost and environmental aspect. However, double bonds in vegetable oil should be substituted to other high reactive functional group due to its low reactivity for synthesizing bio-polymeric materials. ${\alpha}$-eleostearic acid, which is consist of conjugated triene, is the main component of tung oil, and the conjugated triene allows tung oil to have higher reactivity than other vegetable oil. In this study, tung oil is copolymerized with styrene and divinylbenzene to make thermoset resin without any substitution of functional group. Thermal and mechanical properties are measured to investigate the effects of the composition of each monomer on the synthesized thermoset resin. The result shows that the products have only one Tg, which means the synthesized thermoset resins are homogeneous in molecular level. Mechanical properties show that tung oil act as soft segment in the copolymer and make more elastic product. On the other hand, divinylbenzene acts as hard segment and makes more brittle product.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.11
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• pp.24-30
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• 2018

Various investigations of vegetable oil extracted from natural resources are underway because of their low cost and environmental value. On the other hand, the double bonds in vegetable oil should be substituted to other high reactive functional groups due to their low reactivity for synthesizing bio-polymeric materials. ${\alpha}$-eleostearic acid, which consists of a conjugated triene, is the main component of tung oil, and the conjugated triene allows tung oil to have higher reactivity than other vegetable oils. In this study, tung oil was copolymerized with styrene and divinylbenzene to make a thermoset resin without any substitution of functional groups. The thermal and mechanical properties were measured to examine the effects of the composition of each monomer on the synthesized thermoset resin. The results showed that the products have only one Tg, which means the synthesized thermoset resins are homogeneous at the molecular level. The mechanical properties show that tung oil acts as a soft segment in the copolymer and makes a more elastic product. On the other hand, divinylbenzene acts as a hard segment and makes a more brittle product.

• KIPS Transactions on Software and Data Engineering
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• v.4 no.5
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• pp.241-246
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• 2015

Although many different methods have been used to solve stereo correspondent problems, the deviation of accuracy is too big. Among those many methods, the one that uses segmentation information of input image has received high attention in academic field since it is very close to vision recognition. In this thesis, the existing method of acquiring a single value by using the segment information and initial disparity value was viewed in NP-hard problem to propose a new method. In order to verify the validity of the proposed method, well-known data were used for experiment and the resulted data was analyzed. Although there were some disadvantages in the time aspect, it showed somewhat useful results in the accuracy aspect.

• Elastomers and Composites
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• v.57 no.1
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• pp.13-19
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• 2022

Polycarbonate diol-based waterborne polyurethane (WPU) was prepared by prepolymer mixing process. The prepolymer mixture contained the polycarbonate diol, isophorone diisocyanate (IPDI), dimethylol propionic acid, triethylamine, and ethylenediamine (EDA). The NCO/OH ratio in the prepolymer was adjusted by controlling the molar ratio of IPDI, and its effects on the properties of WPU were studied. The structure of WPU was characterized by fourier transform infrared spectroscopy. The average particle size increased and viscosity decreased with increasing NCO/OH ratio and EDA content in WPU. The reduced phase separation between soft and hard segments increased glass transition temperature. The reduction in the thermal decomposition temperature could be attributed to the low bond energy of urethane and urea groups, which constituted the hard segment. Additionally, the polyurethane chain mobility was restricted, elongation decreased, and tensile strength increased. The hydrogen bond between the hard segments formed a dense structure that hindered water absorption.