• Transactions of Materials Processing
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• v.16 no.3 s.93
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• pp.210-214
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• 2007

Manufacturing bulk nanostructured materials with least grain growth from initial powders is challenging because of the bottle neck of bottom-up methods using the conventional powder metallurgy via compaction and sintering. In the study, densification behavior of nano Cu powders during pressureless sintering was investigated using an in-situ optical dilatometer technique. The initial heating and steady temperature stages during the sintering of nano Cu powder compacts were observed. At the initial heating stage, the powder compact has many porosities and full densification needs high temperature and/or high pressure sintering. In the experimental analysis, changes in geometry and density were measured and discussed for optimal consolidation and densification by the in-situ optical dilatometer.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.616-619
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• 2005

OLED display are extremely sensitive to water and oxygen. Developing a thin film encapsulation for this technology has for a long time been elusive. Vitex has developed a multilayer barrier consisting of alternating inorganic and organic layers which can meet the requirements for a successful protection for such displays. In this paper we will discuss the basic process, the model, the results on top and bottom emission OLED displays as well as the application of Barix layers on plastic to create flexible OLED displays. We will show that for displays all the requirement for the telecommunication industry can be met and that the we can scale up to a mass manufacturing process.

• Journal of the Korean institute of surface engineering
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• v.55 no.6
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• pp.328-341
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• 2022

Area selective atomic layer deposition (AS-ALD) is a bottom-up nanopattern fabrication method that can grow the ALD films only on the desired substrate areas without using photolithography and etching processes. Particularly, AS-ALD has attracted great attention in the semiconductor manufacturing process due to its advantage in reducing edge placement error by fabricating self-aligned patterns. In this paper, the basic principles and characteristics of AS-ALD are described. In addition, various approaches for achieving AS-ALD with excellent selectivity were comprehensively reviewed. Finally, the technology development to overcome the selectivity limit of AS-ALD was introduced along with future prospects.

• The Journal of Society for e-Business Studies
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• v.11 no.3
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• pp.53-71
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• 2006

In order to cope with the rapidly changing product development environment, individual manufacturing enterprises are forced to collaborate with each other through establishing a virtual organization. In collaboration, designated organizations work together for mutual gain based on product data interoperability. However, product data interoperability is not fully facilitated due to semantic inconsistency among product data models of individual enterprises. In order to overcome the semantic inconsistency problem, this paper proposes a reference ontology, Reference Domain Ontology(RDO), and a methodology for product data interoperability with semantic consistency using RDO. RDO describes semantics of product data model and metamodel for all application domains in a virtual organization. Using RDO, application domains in a virtual organization can easily understand the product data models of others. RDO is agile and temporal such that it is created with the formation of a virtual organization, copes with changes of the organization, and disappears with the vanishment of the organization. RDO is built by a hybrid approach of top-down using a upper ontology and bottom-up based on the merging of ontologies of application domains in a virtual organization. With this methodology, every domain in a virtual organization can achieve product data model interoperability without model transformation.

• Journal of Fashion Business
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• v.4 no.1
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• pp.45-58
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• 2000

The purpose of this study is to provide for the basic data useful to the development of a quality bassiere featuring a good wearing feeling, to investigate the characteristics of breast shapes by age and suggest a brassiere sizing system for woman. For this purpose, the subjects of anthropometry were 220 women aged between 20 and 59. The anthropometric measurements were analyzed by various statistical methods mean, standard deviation, F-test, Duncan-test, Factor analysis, frequency. The results of this study can be summarized as follows; 1. According to the increase of age, the items of height were decreased and items of width, depth, circumference and length were increased, being obeser and breast point were drooped. So volume and bottom area of breast of 40 50's women were larger than 20 30's women and breast point width of 40 50's women was being wider by increase of the interior of breast. 2. From analyzing the effect of brassiere wearing, it was found that brassiere reformed the breast shape with the breast volume transferred from exterior part to interior part and the bottom area of breast diminished, so brassiere can have the breast location of adult woman up and the breast point width being centered 3. It was found that there was no direct linear relationships between under bust girth and cup size from analysis of breast measurements. Therefore those 2 factors(under bust girth and cup size) was brought into basic item of brassiere sizing system. From the dual distribution table whose intervals had been decided by KS K-0070(1999), it was picked out 12 sizes which had more than 4% of appearance for suggesting brassiere size chart. The sizing system covers 76.36% of all subjects and supply reference measurements relevant to brassiere manufacturing.

• Journal of Fashion Business
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• v.11 no.6
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• pp.101-114
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• 2007

This research aimed to identify the differences, in terms of the pattern, of using wool and jersey for designing jackets and to provide a theorized solution. The object of this study is development of women's tailored jacket pattern by the traits of fabrics with fabrics those are generally used to develop the power of manufacturing technique about fit of jacket. Basic bodies prototype, graphics of sleeves prototype and graphics of jacket pattern those a clothing company at present(on&on, a brand of Beaucre Merchandising Co.,Ltd) is using were used as basics of tailored jacket pattern. Three kinds of fabric(wool, polyester, jersey) were chosen, we made jackets in the same manufacturing process of the clothing company, modified and made up for the weak points and then we compared and analyzed differences of pattern by the traits of fabrics, the results are as follows: 1) We drafted basic tailored style jacket pattern, made a jacket with wool fabric, made wearing experiment, modified and made up for the weak points by the trend, then developed JacketⅠ for study; 2) With JacketⅠ for study as the basic, we made a jacket with polyester fabric, made wearing experiment, modified and made up for the weak points, then developed Jacket II for study; 3) With JacketⅠ for study as the basic, we made a jacket with jersey fabric, made wearing experiment, modified and made up for the weak points, then developed Jacket III for study; 4) We presented final degree of polymerization of pattern with Jacket I II III for study; 5) We compared and analyzed the differences of pattern with the degree of polymerization of pattern with Jacket I(Wool) for study and Jacket II(Polyester), there was no change of size overall except extra amount which happens because of the trait of the fabric in 20 items of body format pattern, there were differences of size in 3 items(height of a sleeve, width of a sleeve, length of a sleeve) among 5 items of sleeves pattern; 6) We compared and analyzed the differences of pattern with the degree of polymerization of pattern with Jacket I(Wool) for study and Jacket III(Jersey) for study, there were differences of size by the kinds of fabric in 11 items(neck point to shoulder point length, Bishoulder point length, back interscye length, front interscye length, armhole circumference, depth of armhole, chest circumference, bust circumference, waist circumference, hip circumference, waist dart) among 20 items of body format pattern, there were differences of size by the kinds of fabric in 5 items(height of a sleeve, circumference of a sleeve, width of a sleeve, length of a sleeve, width of bottom of a sleeve) among 5 items of sleeves pattern.

• Journal of Powder Materials
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• v.15 no.1
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• pp.31-36
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• 2008

In this study, the bottom-up powder metallurgy and the top-down severe plastic deformation (SPD) techniques for manufacturing bulk nanomaterials were combined in order to achieve both full density and grain refinement without grain growth of rapidly solidified Al-20 wt% Si alloy powders during consolidation processing. Continuous equal channel multi-angular processing (C-ECMAP) was proposed to improve low productivity of conventional ECAP, one of the most promising method in SPD. As a powder consolidation method, C-ECMAP was employed. A wide range of experimental studies were carried out for characterizing mechanical properties and microstructures of the ECMAP processed materials. It was found that effective properties of high strength and full density maintaining nanoscale microstructure are achieved. The proposed SPD processing of powder materials can be a good method to achieve fully density and nanostructured materials.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1604-1618
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• 1995

In the process of mechanical assembly design, assembly modeling systems have been used mainly for the design verification before manufacturing by enabling to check the interference and/ or the dynamic and kinematic performance. However, the conventional assembly modeling systems have a shortcoming that they can not be used in the initial design stage but can be used only after the design is fully completed. In other words conventional assembly modeling systems provide bottom-up modeling which means that the detailed modeling of components must precede the definition of relationships between them. To resolve this problem, an assembly modeling system is proposed to provide a top-down modeling environment in which components and assembly can be modeled simultaneously. To this end, an assembly data structure suitable for top-down assembly modeling has been established. Feature positioning Module(FPM) using geometric constraints has been also developed. The Sekective Solving Method proposed for FPM is based on the priority between the constraint equations and enables the designer's intent expressed by geometric constraints to be maintained throughout the whole modeling process. Finally, the feature based modeling technique using two-level features has been developed. Two-level features include an abstract model and a detailed model in a merged form in non-manifold data frame.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.5
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• pp.654-661
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• 2004

In deep drawing of sheet metal, there are many cases in which the uniform and thin wall thickness of the drawn products is more important than the bottom thickness. In this case, we can not easily get the deep drawn products with the uniform and precise wall thickness by only drawing process. Therefore in general the manufacturing processes which both the drawing and the ironing process are proceeded sequentially are used. But this method has the disadvantages of a cost-up, decrease of productivity and degradation of quality, because the ironing process is added after the drawing process. In this study, in order to improve those problems and to enhance the effect of deep drawing, the combined process of redrawing and ironing fur multistep drawing of cylindrical cups is used. In this experiment, we considered the characteristics of the combined process such as the relation between the drawing and ironing rates, the drawing limits and the forces needed for operations. The suggested force prediction shows that it can successfully represent experimental results.

• Steel and Composite Structures
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• v.44 no.2
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• pp.255-270
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• 2022

This manuscript illustrates the dynamic response of nanoscale carbon nanotubes (CNTs) embedded in an elastic media under moving load using doublet mechanics theory, which not considered before. CNTs are modelled by Timoshenko beam theory (TBT) and a bottom to up modelling nano-mechanics is simulated by doublet mechanics theory to capture the size effect of CNTs. To explore the influence of the CNTs configurations on the dynamic behaviour, both armchair and zigzag configurations are considered. The governing equations of motion and the associated boundary conditions are obtained using the Hamiltonian principle. The Navier solution methodology is applied to obtain the solutions for both orientations. Free vibration and forced response under moving loads are considered. The accuracy of the developed procedure is verified by comparing the obtained results with available previous algorithms and good agreement is observed. Parametric studies are conducted to demonstrate effects of doublet length scale, CNTs configurations, moving load velocities as well as the elastic media parameters on the dynamic behaviours of CNTs. The developed procedure is supportive in the design and manufacturing of MEMS/NEMS made from CNTs.