• Journal of Digital Convergence
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• v.10 no.10
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• pp.447-456
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• 2012

In space design or form design step, recognized necessity of digital design practical use. Also, deduced systematized analysis method that can use various function of CAD system actively. These method can promote the practical use because third dimensional digital design escapes plan and design process in concept that get presentation result after is completed, establishes role of effective and systematic digital design at planning and design of space or form. This uses by a design tool that ease designer's judgment and space and form analysis in architectural planning and design process that third dimension digital design is not part by a simplicity design tool. Share and takes advantage of digital design process method that is deduced in this study, need continuance of connection study for more effective and systematic digital design methodology deduction. Need public ownership of teaching material development and teaching method that can deliver extended third dimension digital design process.

• Convergence Security Journal
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• v.22 no.5
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• pp.61-67
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• 2022

The purpose of this study is to analyze research trends in artificial intelligence. For a three-dimensional analysis, an attempt was made to objectively compare and present the difference between the research direction of artificial intelligence in social science and engineering. For the research method, topic modeling was used among the big data analysis methodologies, and 1000 English papers searched with the keyword artificial intelligence (AI) in the academic research information system were used for the analysis data. As a result of the analysis, in the field of social science, it was possible to identify groups formed around the keywords of 'human', 'impact', and 'future' for artificial intelligence, and in the field of engineering, 'artificial intelligence-based technology development', 'system', 'Groups such as 'Risk-Security' were formed.

• The Research Journal of the Costume Culture
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• v.29 no.3
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• pp.374-387
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• 2021

The purpose of this study is to develop up-cycling fashion design methods centered on discarded denim material for the study of original up-cycling design methods. Up-cycling fashion design work was developed using digital clothing technology. This is a recent hot topic among sustainable fashion design methods. Up-cycling fashion design expression methods (categorized as dismantlement, collages, dépaysement, grafting, weaving, and tearing) were centered on design methods. These methods create various three-dimensional modeling effects in planar forms, whereby five pieces can be applied to the fabric and digitally produced. The results are as follows: First, the use of discarded denim fabric for the development of up-cycling fashion design pieces enabled the recycling of existing resources, provided solutions to environmental pollution problems, and provided expansion opportunities for design processes for sustainable fashion products that expand the design value of denim products and their utility. Second, new eco-friendly fashion designs that attempt to achieve diversity in modern fashion trends could be presented through formative contemporary fashion produced by up-cycling work products. Third, up-cycling fashion design work is expected to provide opportunities for eco-friendly fashion design methods. This will expand the value of sustainable fashion design by recycling simple waste materials through the use of three-dimensional digital clothing technology and further through the presentation of expanded life cycles that extend product planning, production, and life cycles.

• International Journal of Stem Cells
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• v.17 no.1
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• pp.38-50
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• 2024

Induced pluripotent stem cell (iPSC) technology has revolutionized various fields, including stem cell research, disease modeling, and regenerative medicine. The evolution of iPSC-based models has transitioned from conventional two-dimensional systems to more physiologically relevant three-dimensional (3D) models such as spheroids and organoids. Nonetheless, there still remain challenges including limitations in creating complex 3D tissue geometry and structures, the emergence of necrotic core in existing 3D models, and limited scalability and reproducibility. 3D bioprinting has emerged as a revolutionary technology that can facilitate the development of complex 3D tissues and organs with high scalability and reproducibility. This innovative approach has the potential to effectively bridge the gap between conventional iPSC models and complex 3D tissues in vivo. This review focuses on current trends and advancements in the bioprinting of iPSCs. Specifically, it covers the fundamental concepts and techniques of bioprinting and bioink design, reviews recent progress in iPSC bioprinting research with a specific focus on bioprinting undifferentiated iPSCs, and concludes by discussing existing limitations and future prospects.

• Elastomers and Composites
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• v.58 no.1
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• pp.44-56
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• 2023

Additive manufacturing (AM) or three-dimensional (3D) printing of metals has been drawing significant attention due to its reliability, usefulness, and low cost with rapid prototyping. Among the various AM technologies, fused deposition modeling (FDM) or fused filament fabrication is receiving much interest because of its simple manufacturing processing, low material waste, and cost-effective equipment. FDM technology uses metal-filled polymer filaments for 3D printing, followed by debinding and sintering to fabricate complex metal parts. An efficient binder is essential for producing polymer filaments and the thermal post-processing of printed objects. This study involved an in-depth investigation of and a fabrication route for a novel multi-component binder system with steel alloy powder (45 vol.%) ranging from filament fabrication and 3D printing to debinding and sintering. The binder system consisted of polyvinyl pyrrolidone (PVP) as a binder and thermoplastic polyurethane (TPU) and polylactic acid (PLA) as a carrier. The PVP binder held the metal components tightly by maintaining their stoichiometry, and the TPU and PLA in the ratio of 9:1 provided flexibility, stiffness, and strength to the filament for 3D printing. The efficacy of the binder system was examined by fabricating 3D-printed cubic structures. The results revealed that the thermal debinding and sintering processes effectively removed the binder/carrier from the cubic structures, resulting in isotropic shrinkage of approximately 15.8% in all directions. The scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) patterns displayed the microstructure behavior, phase transition, and elemental composition of the 3D cubic structure.

• Steel and Composite Structures
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• v.20 no.3
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• pp.623-649
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• 2016

Most of the early studies on plates vibration are focused on two-dimensional theories, these theories reduce the dimensions of problems from three to two by introducing some assumptions in mathematical modeling leading to simpler expressions and derivation of solutions. However, these simplifications inherently bring errors and therefore may lead to unreliable results for relatively thick plates. The main objective of this research paper is to present 3-D elasticity solution for free vibration analysis of continuously graded carbon nanotube-reinforced (CGCNTR) rectangular plates resting on two-parameter elastic foundations. The volume fractions of oriented, straight single-walled carbon nanotubes (SWCNTs) are assumed to be graded in the thickness direction. In this study, an equivalent continuum model based on the Eshelby-Mori-Tanaka approach is employed to estimate the effective constitutive law of the elastic isotropic medium (matrix) with oriented, straight carbon nanotubes (CNTs). The proposed rectangular plates have two opposite edges simply supported, while all possible combinations of free, simply supported and clamped boundary conditions are applied to the other two edges. The formulations are based on the three-dimensional elasticity theory. A semi-analytical approach composed of differential quadrature method (DQM) and series solution is adopted to solve the equations of motion. The fast rate of convergence of the method is demonstrated and comparison studies are carried out to establish its very high accuracy and versatility. The 2-D differential quadrature method as an efficient and accurate numerical tool is used to discretize the governing equations and to implement the boundary conditions. The convergence of the method is demonstrated and to validate the results, comparisons are made between the present results and results reported by well-known references for special cases treated before, have confirmed accuracy and efficiency of the present approach. The novelty of the present work is to exploit Eshelby-Mori-Tanaka approach in order to reveal the impacts of the volume fractions of oriented CNTs, different CNTs distributions, various coefficients of foundation and different combinations of free, simply supported and clamped boundary conditions on the vibrational characteristics of CGCNTR rectangular plates. The new results can be used as benchmark solutions for future researches.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.3
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• pp.117-126
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• 2018

Due to intelligent transport systems, location-based applications, and augmented reality, demand for image maps and 3D (Three-Dimensional) maps is increasing. As a result, data acquisition using UAV (Unmanned Aerial Vehicles) has flourished in recent years. However, even though orthophoto map production and research using UAVs are flourishing, few studies on 3D modeling have been conducted. In this study, orthophoto and 3D modeling research was performed using various angle images acquired by a UAV. For orthophotos, accuracy was evaluated using a GPS (Global Positioning System) survey that employed VRS (Virtual Reference Station) acquired checkpoints. 3D modeling was evaluated by calculating the RMSE (Root Mean Square Error) of the difference between the outline height values of buildings obtained from the GPS survey to the corresponding 3D modeling height values. The orthophotos satisfied the acceptable accuracy of NGII (National Geographic Information Institute) for a 1/500 scale map from all angles. In the case of 3D modeling, models based on images taken at 45 degrees revealed better accuracy of building outlines than models based on images taken at 30, 60, or 75 degrees. To summarize, it was shown that for orthophotos, the accuracy for 1/500 maps was satisfied at all angles; for 3D modeling, images taken at 45 degrees produced the most accurate models.

• Journal of Cadastre & Land InformatiX
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• v.47 no.1
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• pp.179-190
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• 2017

A terrestrial LiDAR survey was conducted and unmanned aerial vehicle(UAV) images were taken for target cultural properties to present the utilization measures of terrestrial LiDAR and UAV in three-dimensional modeling of cultural properties for the identification of the status and restoration of cultural properties. Then the accuracy of the point clouds generated through this process was compared, an overlap analysis of the 3D model was conducted, and a convergence model was created. According to the results, the modeling with terrestrial LiDAR is more appropriate for precise survey because 3D modeling for the detection of displacement and deformation of cultural properties requires an accuracy of mm units. And UAV model has limitation as the impossibility of detailed expression of parts with sharp unevenness such as cracks of bricks. However, it is found that the UAV model has a wide range of modeling and has the advantage of modeling of real cultural properties. Finally, the convergence model created in this study using the advantages of the terrestrial LiDAR model and the UAV model could be efficiently utilized for the basic data development of cultural properties.

• Geophysics and Geophysical Exploration
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• v.7 no.2
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• pp.148-154
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• 2004

This article reviews the development of three-dimensional (3-D) magnetotelluric (MT) modeling. The 3-D modeling of electromagnetic fields is essential in understanding the physics of MT soundings, and in implementing an inversion method to reconstruct a 3-D resistivity image. Although various numerical schemes have been developed over the last two decades, practical methods have been quite limited. However, the recent rapid improvement in computer speed and memory, as well as the advance in iterative solution algorithms for a large system of equations, makes it possible to model the MT responses of complex 3-D structures, which have been very difficult to simulate before. The use of staggered grids in finite difference method has become popular, conserving a magnetic flux and an electric current and allowing for realistic discontinuous fields. The convergence of numerical solutions has been greatly accelerated by adopting Krylov subspace methods, proper preconditioning techniques, and static divergence corrections. The vector finite-element method using edge elements is also free from the discontinuity problem, and seems a natural choice for modeling complex structures including irregular topography because its flexibility allows one to capture full geometric complexity.

• Journal of information and communication convergence engineering
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• v.12 no.1
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• pp.46-52
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• 2014

This article presents key research needs in three-dimensional integrated circuit (3D IC) architectural floorplanning. Architectural floorplaning is done at a very early stage of 3D IC design process, where the goal is to quickly evaluate architectural designs described in register-transfer level (RTL) in terms of power, performance, and reliability. This evaluation is then fed back to architects for further improvement and/or modifications needed to meet the target constraints. We discuss the details of the following research needs in this article: block-level modeling, through-silicon-via (TSV) insertion and management, and chip/package co-evaluation. The goal of block-level modeling is to obtain physical, power, performance, and reliability information of architectural blocks. We then assemble the blocks into multiple tiers while connecting them using TSVs that are placed in between hard IPs and inside soft IPs. Once a full-stack 3D floorplanning is obtained, we evaluate it so that the feedback is provided back to architects.