• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.378-381
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• 2008

The buckling behavior of cylindrical shape-memory alloy and aluminum tube is investigated at room temperature using a split Hopkinson pressure bar and an Instron hydraulic machine with a specially designed recording system. The shape-memory alloy at superelastic property regime buckles gradually in quasi-static loading, and fully recovers upon unloading. However, the buckling of aluminum tube is sudden and catastrophic, and shows permanent deformation. This gradual buckling of shape-memory alloy is associated with the forward and reverse transformation of stress-induced martensite and seems to have a profound effect on the unstable deformation of tube structures made from shape-memory alloy.

• Journal of Ocean Engineering and Technology
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• v.13 no.3 s.33
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• pp.12-20
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• 1999

In this paper, method for mapping a three-dimensional shape into the two-dimensional plane will be introduced. This method is referred to geometric modelling and means a transformation between the flat sheet and final surface. The initial blank shape represents the original configuration of the final shape formed into three dimensional surface. The initial constant constant area mapping hypothesis was used in this paper. This technique will be applied to the basic data for an interactive computer design capable of dealing with typical stamping process, including deep parts and complex shapes.

• Korean Institute of Interior Design Journal
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• v.25 no.1
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• pp.163-171
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• 2016

The objectives of this study is to analyze the characteristics of Chinese traditionality expression at restaurants in Beijing area. 12 restaurants were selected and visited for the investigation research. The results were as follows. First, traditional reproduction was found mainly manifested through the reproduction of traditional ornaments, in particular, the facade and interior element ornaments. Second, Traditional transformation was mainly manifested in replacement material while changing the shape slightly, or to stretch or shorten prototype shape and other negative deformation methods which did not largely out of the scope of traditional reproduction. Third, Traditional reinterpretation was expressed by abstract, symbol or metaphor on designs, usually people can not directly recognize the traditional archetype. When compare with traditional reproduction or traditional transformation, traditional reinterpretation was relatively fewer, however, in this study the traditional reinterpretation and traditional transformation have same numerical result. Reinterpretation as a positive performance method of traditional modernized, it was encouraging the phenomenon, especially in the ceiling design. Chinese traditional cloud patterns have been three-dimensional and diversification of use. And in the wall design, traditional elements have been extremely simplistic or adopted a wide variety of traditional elements, it may be preferred in diversity. In addition, furniture was tinge traditional elements in modern form, lighting was added symbolize color or picture on the traditional lighting which shape was simplified to emphasize space's traditional. But the facade, sign board, floor, and window element seems the range of variation was not wild, promote more use the positive traditional reinterpretation method.

• Journal of the Korean Home Economics Association
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• v.35 no.4
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• pp.159-172
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• 1997

The purpose of this study was to investigate the slacks pattern making on the movement -fitness of the hip region. The experimental items were divided into the 5 lower limb movements(M1-M5) and the 12 revision pattern constructions of slacks. This study was done by clothing pressure test sensory evaluation test and the difference shape-transformation of wearing-slacks. The summarized finding resulted from experiments and investigation are suggested as follows: First by the clothing pressure tested by lower limb movements the clothing pressure score of the rabbit leap movement(M3) was the highest of all lower limb movements and the order of it in the another movement was the sit on knee(M4) the sit on chair(M2) the noble sitting(M5) from the highest to the lowest. And in comparision of clothing pressure tested by revision pattern to cover the extend of crotch-length 20。 inclined back-line construction method (CA4) showed the lowest. And in comparision of clothing pressure tested by revision pattern to cover the extend of crotch-length 20。 inclined back-line construction method (CA4) showed the lowest. And also for a role to cover hip circumference extendign CC4(1/5 hip.1cm longrightarrow linked back -line) method showed the lowest. Second by the sensory evaluation test based on the movement and revision patterns it was found that the functional factor score of the rabbit leap movement was the lowest in all movement however the score of revision patterns were higher than basic pattern. Third by the test to show difference in the shape-transformation of wearing-slacks on chair(M2) also need to be analyzed. The ration of the shape-transformation of the knee region showed the least value in the increased patterns of inclined angle of back-line(CA) and the differential methods of back-line inclined pattern making. But that of the hem-line did not show remarkable difference.

• Journal of the Korean Home Economics Association
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• v.34 no.2
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• pp.43-55
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• 1996

The purpose of this study was to investigate the slacks pattern making on the movement-fitness of the knee region. The experimental items were divided into the lower limb movement (M1~M5) and slacks pattern designs (4 : basic pattern, in-pleats, side-pleats, seam-line increase). This study was done by clothing pressure test, sensory evaluation test and the difference shape-transformation of wearing-slacks. The summarized finding resulted from experiments and investigation are suggested as follows ; First, the clothing pressure test showed that the order of clothing pressure in the movement was the rabbit leap movement (M3), the sit on knees (M4), the nobleman sitting (M5), the sit on chair (M2) from the highest to the lowest. In the comparison of clothing pressure tested by blocks of lower-limb, center front knee region shows the highest of 300g/cm2. In it by constructional methods, the clothing pressure of in-pleats, side-pleats methods shows lower than basic pattern, hem-line increase methods. Also in comparison of the two methods, in-pleats method shows lower than side-pleats method. Second, by the sensory evaluation test based on the lower-limb movements and constructional methods of slacks, it was found that the functional factor score of the rabbit leap movement was also the waist, hip, knee region was the lowest in all blocks. And in the comparison of constructional methods, in-pleats method was the highest in all methods. Third, in consideration of the difference in the shape-transformation of wearing-slacks on the movement-fitness, pleats pattern design methods showed that the ratio of shape-transformation was lower than basic on seam-line increase methods. But the difference of the side-pleats and in-pleats methods was litle. According to these investigation, the slacks pattern making caused by movement-fitness on the knee region, in-pleats design method was the functional slacks pattern.

• Journal of the Korean Society for Heat Treatment
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• v.37 no.2
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• pp.79-85
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• 2024

The effects of annealing heat treatment and the addition of Cu element on the shape memory effect of the NiTi-based alloy were investigated by analyzing differential scanning calorimeter results and characterizing recovery rate through 3D scanning after Vickers hardness test. Through 3D scanning of impressions after Vickers hardness test, the strain recovery rates for specimens without annealing treatment and annealed specimens at 400, 450, and 500℃ were measured as 45.96%, 46.76%, 52.37%, and 43.57%, respectively. This is because as the annealing temperature increases, both B19' and NiTi₂ phases, which can impede martensitic transformation, are incorporated within the NiTi matrix. Particularly, additional phase transformation from R-phase to B19' observed in specimens annealed at 400 and 450℃ significantly contributes to the improvement in strain recovery rates. Additionally, the results regarding the Cu element content indicate that when the total content of Ni and Cu is below 49.6 at.%, the precipitation of fine B19' and NiTi₂ phases within the matrix can greatly influence the transformation enthalpy and temperature range, resulting in relatively lower strain recovery rates in NiTi alloys with a small amount of Cu element produced in this study.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2461-2468
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• 2000

In this paper, single fiber pull-out test is used to measure the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite with temperature. Fiber and matrix of $Ti_{50}-Ni_{50}$ shape memory alloy composite are respectively $Ti_{50}-Ni_{50}$ shape memory alloy and epoxy resin. To strengthen the interfacial bonding shear stress, various surface treatments are used. They are the hand-sanded surface treatment, the acid etched surface treatment and the silane coupled surface treatment etc.. The interfacial bonding shear strength of surface treated shape memory alloy fiber is greater than that of surface untreated shape memory alloy fiber by from 10% to 16%. It is assured that the hand-sanded surface treatment and the acid etched surface treatment are the best way to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory composite. The best treatment condition of surface is 10% HNO$_3$ solution in the etching method to strengthen the interfacial bonding shear strength of $Ti_{50}-Ni_{50}$ shape memory alloy composite.

• Journal of the Korean Society for Heat Treatment
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• v.22 no.2
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• pp.101-107
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• 2009

Effect of isochronic aging on transformation behavior of Ti-50.85at%Ni alloy were investigated by differential scanning calorimeter (DSC). The martensitic transformation temperature increases with increasing annealing temperature until reaching a maximum, and then decreases with further increasing annealing temperature. This can be rationalized by interaction between the distribution of $Ti_3Ni_4$ precipitates and Ni content in the matrix. The R-phase transformation temperature increases with increasing annealing temperature until reaching a maximum, and then decreases with a further increase of annealing temperature. This is attributed to the change of Ni content in the matrix caused by precipitation of $Ti_3Ni_4$. The occurrence of the multiple-stage martensitic and R-phase transformation is attributed to precipitation-induced inhomogeneity of the matrix, both in terms of composition and of internal stress fields.

• Transactions on Electrical and Electronic Materials
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• v.13 no.1
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• pp.19-22
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• 2012

Transformation behavior of rapidly solidified Ti-47.3Ni (at%) alloy ribbons and thermal stability of the R phase in the ribbons were investigated by means of differential scanning calorimetry (DSC), X-ray diffraction, and transmission electron microscopy. Rapidly solidified Ti-47.3Ni alloy ribbons showed the two-stage B2-R-B19' martensitic transformation behavior. The B2-R transformation in the ribbons was observed even after annealing at 1,223 K, which was attributed to the fact that a specific orientation relationship between $Ti_2Ni$ and matrix in the ribbons is maintained after annealing at 1,223 K. The DSC peak temperature of the B2-R transformation ($T_R^*$) decreased with raising annealing temperature, which was attributed to the increased volume fraction of $Ti_2Ni$, thus causing an increased Ni content in the matrix.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.4
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• pp.75-82
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• 2018

BIM(Building Information Modeling) based design process can initiatively conduct a task through all phases from early design step to construction and maintenance step. Also BIM efficiently manage the building's energy by reflecting 3D design and construction life cycle. This paper proposes an efficient process to build AHU's BIM-based library. This study involves analyzing an AHU model for development of design module, and making the template model using the same 12 parts including the shapes of ducts, doors and frames. In consideration of each shape's direction and the status of existence, which are detailed shapes of parts upon making the template model, all the shapes of the AHU model can be expressed. By applying parametric modeling to the template model, a quick and precise modification and transformation can be conducted, thus the efficiency is enhanced. A user selects an AHU model from a 2D model selection program, and extracts shape information. The final AHU shape is completed through the automation work of unnecessary shape deletion by bringing the extracted shape information to the template model. This enables the user to build efficient AHU's BIM-based library, since the quick and precise modification and transformation of the template model are possibile, and all AHU model shapes can be expressed.