• Journal of the Korean Society for Precision Engineering
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• v.18 no.9
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• pp.61-70
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• 2001

This paper introduces a new digitization method with sensor fusion for shape measurement in reverse engineering. Digitization can be classified into contact and non-contact type according to the measurement devices. Important thing in digitization is speed and accuracy. The former is excellent in speed and the latter is good for accuracy. Sensor fusion in digitization intends to incorporate the merits of both types so that the system can be automatized. Firstly, non-contact sensor with vision system acquires coarse 3D point data rapidly. This process is needed to identify and loco]ice the object located at unknown position on the table. Secondly, accurate 3D point data can be automatically obtained using scanning probe based on the previously measured coarse 3D point data. In the research, a great number of measuring points of equi-distance were instructed along the line acquired by the vision system. Finally, the digitized 3D point data are approximated to the rational B-spline surface equation, and the free-formed surface information can be transferred to a commercial CAD/CAM system via IGES translation in order to machine the modeled geometric shape.

• Proceedings of the Korea Society of Design Studies Conference
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• 2001.10a
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• pp.10.1-10
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• 2001

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.227-228
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• 2022

In order to achieve the goal of cost management, which is one of the three major management goals of building production, this paper introduces an approximate cost estimating automation technology in the design stage as the importance of predicting construction costs increases. BIM is used for accurate estimating, and the quantity of structural members and finishing materials is calculated by creating a 3D model of the actual building. However, only 2D basic design drawings are provided when making an estimating. Therefore, for accurate quantity calculation, digitization of 2D drawings is required. Therefore, this research calculates the quantity of concrete structural members by calculating the area for the recognition area through 2D drawing recognition technology incorporating computer vision. It is judged that the development technology of this research can be used as an important decision-making tool when predicting the construction cost in the design stage. In addition, it is expected that 3D modeling automation and 3D structural analysis will be possible through the digitization of 2D drawings.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.6
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• pp.583-590
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• 2021

This paper is a study on the digitization of an analog 3D pen. The term digital implies features such as homeostasis, transformability, combinability, reproducibility, and convenience of storage. One device that produces a combination of these digital characteristics is a 3D printer, but its industrial use is limited due to low productivity and limitations with materials and physical characteristics. In particular, improvements are required to use 3D printers, such as better user accessibility owing to expertise and skills in modeling software and printers. Complementing this fact is the 3D pen, which is excellent in portability and ease of use, but has a limitation in that it cannot be digitized. Therefore, in order to secure a digitalization capability and ease of use, and to secure the safety of printing materials that pose controversial hazards during the printing process, research problems and alternatives have been derived by combining food, and digitization was demonstrated with a newly developed 3D pen. In order to digitize the 3D pen, a sensor in a structured device detects the motion of an analog 3D pen, and this motion is converted into 3D data (X-Y-Z coordinate values) through a spatial analysis algorithm. To prove this method, the similarity was confirmed by visualization using MeshLab version 1.3.4. It is expected that this food pen can be used in youth education and senior healthcare programs in the future.

• The Journal of Engineering Geology
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• v.29 no.4
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• pp.383-391
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• 2019

Bio-grouting based on microbial-induced calcite precipitation (MICP) is recently emerging as a novel and environmentally friendly technique for improvement of coarse-grained ground. To date, the mechanical behaviour of bio-grouted coarse-grained soil with different calcite contents and grain sizes still remains poorly understood. The primary objective of this study is to investigate the influence of calcite content on the mechanical properties of bio-grouted coarse-grained soil with different grain sizes. This is achieved through an integrated study of uniaxial loading experiments of bio-grouted coarse-grained soil, 3D digitization of the grains in conjunction with discrete element modelling (DEM). In the DEM model, aggregates were represented by clump logic based on the 3D morphology digitization of the typical coarse-grained aggregates while the CaCO₃ was represented by small-sized bonded particle model. The computed stress-strain relations and failure patterns of the bio-grouted coarse-grained soil were validated against the measured results. Both experimental and numerical investigation suggest that aggregate sizes and calcite content significantly influence the mechanical behaviour of bio-cemented aggregates. The strength of the bio-grouted coarse-grained soil increases linearly with calcite content, but decreases non-linearly with the increasing particle size for all calcite contents. The experimental-based DEM approach developed in this study also offers an optional avenue for the exploring of micro-mechanisms contributing to the mechanical response of bio-grouted coarse-grained soils.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.1
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• pp.123-136
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• 2023

To develop smart sportswear capable of measuring biometric data, we created a close-fitting pattern using two- and three-dimensional (2D and 3D, respectively) methods. After 3D virtual fitting, the tightness of each pattern was evaluated using image processing of contact points, mesh deviation, and cross-sectional shapes. In contact-point analysis, the 3D pattern showed high rates of contact with the body (84.6% and 93.1% for shirts and pants, respectively). Compared with the 2D pattern, the 3D pattern demonstrated closer contact at the lower chest, upper arm, and thigh regions, where electrocardiography and electromyography were primarily carried out. The overall average gap was also lower in the 3D pattern (5.27 and 4.66 mm in shirts and pants, respectively). In the underbust, waist, thigh circumference, and mid-thigh circumference, the cross-section distance between clothing and body was showed a statistically significant difference and evenly distributed in the 3D pattern, exhibiting more closeness. The tightness and fit of the 3D smart sportswear sensor pattern were successfully evaluated. We believe that this study is critical, as it facilitates the comparison of different patterns through visualization and digitization through 3D virtual fitting.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.153.6-153
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• 2001

3-Dimentional 3D digitization of the human is a technology that is still relatively new. There are present uses such as radiotherapy, identification systems and commercial uses and potential future applications. In this paper, we analyzed and experimented to determine the easiest and most efficient method, which would give us the most accurate results. We also constructed a database of realistic expressions and high quality human heads. We scanned people´s heads and facial expressions in 3D using a Minolta Vivid 700 scanner, then edited the models obtained on a Silicon Graphics workstation. Research was done into the present and potential uses of the 3D digitized models of the human head and we develop ideas for ...

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.4
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• pp.186-192
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• 2021

Recently, the demand for more precise and demand-oriented customized spatial information is increasing due to the 4th industrial revolution. In particular, the use of 3D spatial information and digital twins which based on spatial information, and research for solving social problems in cities by using such information are continuously conducted. Globally, non-face-to-face services are increasing due to COVID-19, and the national policy direction is also rapidly progressing digital transformation, digitization and virtualization of the Korean version of the New Deal, which means that 3D spatial information has become an important factor to support it. In this study, physical objects for cities defined by world organizations such as ISO, OGC, and ITU were selected and the target of the 3D object model was limited to buildings. Based on CityGML2.0, the data collected using a drone suitable for building a 3D model of a small area is selected to be updated through road name address and building ledger, which are administrative information related to this, and LoD2.5 data is constructed and urban space. It was intended to suggest an object update method for a 3D building among data.

• Fashion & Textile Research Journal
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• v.23 no.4
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• pp.504-514
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• 2021

This study attempted to extract and structure the job skills required for 3D designers, which have been recently introduced to the fashion industry. The study aimed to materialize and objectify the 3D designer's job, using a focus group interview for the survey. The 3D designer has the TD task of making 3D virtual samples using the pattern files developed in Pattern CAD. Graphic design and fabric digitization are also major tasks for the 3D designer. CLO is mainly used for 3D virtual sample production, and PixPlant, Substance, Photoshop, Cinema 4D, Daz studio, and 3ds MAX are used for image and avatar editing. As per the job skills required for 3D design work, basic knowledge about patterns and sewing, skill in 3D virtual clothing technology, ability to use various software, and English skills were considered important, in that order. In particular, the need for knowledge about patterns and sewing became more important than the skill in 3D virtual clothing technology itself. To train 3D designers, it was found that not only 3D virtual clothing software, but also education on patterns and clothing construction, CAD developer's curriculum certification system, and 3D designer qualification management were required. In addition, 3D designers are recognized as an essential job in fashion vendors, and the demand for domestic brands is increasing. The biggest limitation of the 3D virtual clothing system is the perfection of the digital fabric. Also, technical improvement is needed.

• Tunnel and Underground Space
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• v.12 no.4
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• pp.268-276
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• 2002

In this study, a 3D coordinate measurement system equipped with a laser displacement meter for digitizing rock joint surface was established and the digitized data were used to calculate several roughness parameters. The parameters used in this study were micro avenge inclination $angle(i_{ave})$, average slope of joint $asperity(SL_{ ave})$, root mean square of $i-angle(i_{rms})$, standard deviation of height(SDH), standard deviation of $i-angle(SD_i)$, roughness profile $index(R_P)$, and fractal dimension(D). The relationships between the roughness parameters based on the digitzation of the surface profile were analyzed. Since the measured value varied according to the degree of reflection and the variation of colors at the measuring point, rock joint surface was painted in white to minimize the influence of the surface conditions. The comparison of the measured values and roughness parameters before and after painting revealed the better consequence from measurement on the painted surfaces. Also, effect of measuring interval was studied. As measured interval was increased, roughness parameters were exponentially decreased. The incremental sequence of degree of decrease was $SDH\; i_{ave},\; i_{rms},\; SD_i,\;and\; R_ p-1$. As a result of comparison of parameters from pin-type measurement system and laser type measurement system, all value of parameters were higher when laser-type measurement system was used, except SDH.