• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.26 no.1
• /
• pp.108-113
• /
• 2017

In this paper, we proposed a three-dimensional(3D) scanning system based on laser vision technique for 3D model reconstruction. The proposed scanning system consists of line laser, camera, and turntable. We implemented the 3D scanning system using low quality elements. Although these are low quality elements, we reduced the 3D data reconstruction errors greatly using two methods. First, we developed a maximum brightness detection algorithm. This algorithm extracts the maximum brightness of the line laser to obtain the shape of the object. Second, we designed a new laser control device. This device helps to adjust the relative position of the turntable and line laser. These two methods greatly reduce the measuring noise. As a result, point cloud data can be obtained without complicated calculations.

• Nuclear Engineering and Technology
• /
• v.53 no.1
• /
• pp.30-43
• /
• 2021

In the 2D/1D method, a global adjoint CMFD based on the generalized equivalence theory is built to synthesize the 2D radial MOC adjoint and 1D axial NEM adjoint calculation and also to accelerate the iteration convergence of 3D whole-core adjoint transport calculation. Even more important, an advanced yet accurate two-level (TL) CMFD acceleration technique is proposed, in which an equivalent one-group adjoint CMFD is established to accelerate the multi-group adjoint CMFD and then to accelerate the 3D whole-core adjoint transport calculation efficiently. Based on these method, a new code is developed to perform 3D adjoint neutron flux calculation. Then a set of VERA and C5G7 benchmark problems are chosen to verify the capability of the 3D adjoint calculations and the effectiveness of TL CMFD acceleration. The numerical results demonstrate that acceptable accuracy of 2D/1D adjoint calculations and superior acceleration of TL CMFD are achievable.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.19 no.3
• /
• pp.633-640
• /
• 2024

This study develops AI-based 3D body shape modeling technology that can be utilized in the healthcare sector, proposing a system that enables monitoring of users' body shape changes and health status. Utilizing data from Size Korea, the study developed a model to generate 3D body shape images from 2D images, and compared various models to select the one with the best performance. Ultimately, by proposing a system process through the developed technology, including personalized health management, exercise recommendations, and dietary suggestions, the study aims to contribute to disease prevention and health promotion.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2011.07a
• /
• pp.329-330
• /
• 2011

3D 영상산업이 발전해 오면서 현재 3D 영상으로 가장 많이 사용되는 것이 바로 stereoscopic 영상이다. 이러한 영상은 인간의 뇌를 속임으로써 화면에 비쳐지는 영상이 마치 화면 밖에 위치하는 것 같은 착각을 일으키게 만들어 3D영상을 인식할 수 있게 해준다. 이때 사람이 양안시를 인식하는 문제에 관한 연구는 이미 안경학에서 많은 발전을 이루어 왔지만, 현재 논의의 중점인 3D 양안시력은 평소 사람이 사용하는 양안시가 아닌 3D Display에서 비춰지는 영상을 다양한 방법으로 양쪽 눈에 다른 영상을 인식하게 함으로써 입체를 인식하게 하는 것이며, 이러한 3D 양안시력을 측정하는 방법에 대해서는 기존의 양안시력과는 다른 측정 방법을 적용하여야 한다. 따라서 이 논문에서는 이러한 3D 입체 영상에 대한 입체시를 측정하는 방법에 대하여 제안한다.

• Journal of Information Processing Systems
• /
• v.7 no.1
• /
• pp.63-74
• /
• 2011

As a powerful and flexible processor, the Graphic Processing Unit (GPU) can offer a great faculty in solving many high-performance computing applications. Sweep3D, which simulates a single group time-independent discrete ordinates (Sn) neutron transport deterministically on 3D Cartesian geometry space, represents the key part of a real ASCI application. The wavefront process for parallel computation in Sweep3D limits the concurrent threads on the GPU. In this paper, we present multi-dimensional optimization methods for Sweep3D, which can be efficiently implemented on the finegrained parallel architecture of the GPU. Our results show that the overall performance of Sweep3D on the CPU-GPU hybrid platform can be improved up to 4.38 times as compared to the CPU-based implementation.

• Journal of Fashion Business
• /
• v.22 no.2
• /
• pp.1-13
• /
• 2018

3D printing technology, which is expected to play a leading role within the Fourth Industrial Revolution, is becoming distinguished not only in the space, automotive, medical and engineering industries, but also in the area of design. The fashion and textile structures created by 3D printing technology were classified into three types - basic structure, unified structure, and a new physical structure. When traditional weaving, knitting, and stitching was reinterpreted through 3D printing, there were apparent limitations in reproducing the characteristics of fabric structures due to differences in the materials and structures of traditional textiles. New physical structures are being developed to break away from merely reproducing traditional textile structures, and to bring out the characteristics of 3D printing technology. As examples of new physical structures, there are the kinematics structure which utilizes the hinge method, mesostructure cellular material, and the N12 disk structure. Such techniques potentially open a new paradigm of fashion and textile structures. Some innovative aspects of 3D printing technology may result in changes in the methods of collaboration, manufacturing, and distribution. Designers are receiving help from specialists of various backgrounds to merge 3D printing technology to create original works. Also, 3D printing not only makes personalized custom designs available, but shortens the distribution channels, foretelling a change within the fashion and textile industry.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.17 no.2
• /
• pp.83-88
• /
• 2018

Additive manufacturing (AM) technologies have attracted wide attention as key technologies for the next industrial revolution. Among AM technologies using various materials, powder bed fusion (PBF) processes and direct energy deposition (DED) are representative of the metal 3-D printing process. Both of these processes have a common feature that the laser is used as a heat source to fabricate the 3-D shape through melting of the metal powder and solidification. However, the material properties of the deposited metals differ when produced by different process conditions and methods. 17-4 precipitation-hardening stainless steel (17-4PH SS) is widely used in the field of aircraft, chemical, and nuclear industries because of its good mechanical properties and excellent corrosion resistance. In this study, we investigated the differences in microstructure and mechanical properties of deposited 17-4PH SS by PBF and DED processes, including the heat treatment effect.

• Nuclear Engineering and Technology
• /
• v.51 no.5
• /
• pp.1436-1443
• /
• 2019

A fast gamma-ray dose rate assessment method for complex geometries based on stylized model reconstruction and point-kernel method is proposed in this paper. The complex three-dimensional (3D) geometries are imported as a 3DS format file from 3dsMax software with material and radiometric attributes. Based on 3D stylized model reconstruction of solid mesh, the 3D-geometrical solids are automatically converted into stylized models. In point-kernel calculation, the stylized source models are divided into point kernels and the mean free paths (mfp) are calculated by the intersections between shield stylized models and tracing ray. Compared with MCNP, the proposed method can implement complex 3D geometries visually, and the dose rate calculation is accurate and fast.

• Journal of the Semiconductor & Display Technology
• /
• v.18 no.3
• /
• pp.66-71
• /
• 2019

In shape from focus (SFF) methods, the quality of image focus volume plays a vital role in the quality of 3D shape reconstruction. Traditionally, a linear 2D filter is applied to each slice of the image focus volume to rectify the noisy focus measurements. However, this approach is problematic because it also modifies the accurate focus measurements that should ideally remain intact. Therefore, in this paper, we propose to enhance the focus volume adaptively by applying 3-dimensional weighted least squares (3D-WLS) based regularization. We estimate regularization weights from the guidance volume extracted from the image sequences. To solve 3D-WLS optimization problem efficiently, we apply a technique to solve a series of 1D linear sub-problems. Experiments conducted on synthetic and real image sequences demonstrate that the proposed method effectively enhances the image focus volume, ultimately improving the quality of reconstructed shape.

• Ceramist
• /
• v.23 no.1
• /
• pp.4-15
• /
• 2020

The recent advances and popularity of 3D printing technology have centered around building polymerbased 'plastic' materials, due to their low cost, simple and efficient processing, and mechanical toughness. For this reason, printable polymers are actively recruited to create 'ceramic resins' that allow more facile fabrication of ceramic materials that are difficult to print directly. Herein, a brief history and the current state of ceramic 3D printing technology aided by polymer is summarized. In addition, a new ceramic 3D printing technology using polymer-derived ceramics (PDC) is also introduced.