• Journal of the Semiconductor & Display Technology
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• v.22 no.4
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• pp.26-31
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• 2023

We investigated the impact of NF₃ / H₂O remote plasma dry cleaning conditions on the SiO₂ etching rate at different preparation states during the fabrication of ultra-large-scale integration (ULSI) devices. This included consideration of factors like Si crystal orientation prior to oxidation and three-dimensional structures. The dry cleaning process were carried out varying the parameters of pressure, NF₃ flow rate, and H₂O flow rate. We found that the pressure had an effective role in controlling anisotropic etching when a thin SiO₂ layer was situated between Si₃N₄ and Si layers in a multilayer trench structure. Based on these observations, we would like to provide further guidelines for implementing the dry cleaning process in the fabrication of semiconductor devices having 3D structures.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.167-170
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• 2005

The two-dimensional (2D) and three-dimensional (3D) diamond-like carbon (DLC) stamps for ultraviolet nanoimprint lithography (UV-NIL) were fabricated using two kinds of methods, which were a DLC coating process followed by the focused ion beam (FIB) lithography and the two-photon polymerization (TPP) patterning followed by nano-scale thick DLC coating. We fabricated 70 nm deep lines with a width of 100 nm and 70 nm deep lines with a width of 150 nm on 100 nm thick DLC layers coated on quartz substrates using the FIB lithography. 200 nm wide lines, 3D rings with a diameter of $1.35\;{\mu}m$ and a height of $1.97\;{\mu}m$, and a 3D cone with a bottom diameter of $2.88\;{\mu}m$ and a height of $1.97\;{\mu}m$ were successfully fabricated using the TPP patterning and DLC coating process. The wafers were successfully printed on an UV-NIL using the DLC stamp. We could see the excellent correlation between the dimensions of features of stamp and the corresponding imprinted features.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.4
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• pp.259-263
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• 1998

High molecular weight glutenin (HMW-Glu) subunit compositions of 73 Korean wheat cultivars and experimental lines were evaluated by using one dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This method is suitable for obtaining a good resolution of 1Dx2 and 1Ax2$^*$ without adverse effects on separation of other HMW-Glu subunits. Korean wheats examined in this study could be divided into 15 different groups on the basis of HMW-Glu subunit compositions. From the wheat lines tested, it was identified that there were three alleles at the Glu-Al, five at the Glu-Bl and three at the Glu-D1 loci. The null allele of the Glu-Al was occurred in high frequency (79.4%), while low frequencies for 1Ax1 (12.3%) and 1Ax2$^*$(8.2%) were found. High frequency (75.3%) of the subunit pairs of 1Bx7+1By8 at the Glu-Bl loci compared with other subunits was found. The frequencies of subunits 1Dx2. 2+1Dy12 and 1Dx2+1Dy12 from the Glu-D1 loci were 54. 8% and 37.0%, respectively. However, a few Korean wheat lines (8.2%) carried 1Dx5 + 1Dy10 subunit pair which are responsible for good breadmaking quality. The information of HMW-Glu subunit compositions provide a useful tool to characterize wheat lines, and can be directly used in selection of breeding lines of different end-use properties.

• The Journal of the Korea Contents Association
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• v.20 no.7
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• pp.525-533
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• 2020

In recent years, the VR-interactive action contents industry, which utilizes five senses of human bodies, has continued to grow through areas such as games, tourism, movies, performances and exhibitions, but it has reached to breaking point by unrealistic visual elements. Therefore, the purpose of this study is to analyze the effect of each evaluation factor based on visual immersion of interactive type of VR action contents to overcome the limitations. For this study, firstly, prior research is reviewed. Secondly, the evaluation factors of visual immersion of interactive type of VR action contents and hypothesis are to be derived. Research finding is that there is no difference to recognize proximity, three-dimensionality, visibility and immersion by gender. Also, in order to influence visual immersion, it is important that 3D modeling of characters and objects must be sophisticated to be fit in with their surroundings and lighting. This makes user to be confused where they are actually in.

• Journal of Korean Foot and Ankle Society
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• v.9 no.1
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• pp.94-98
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• 2005

Purpose: To compare the radiographic evaluations between two radiographic views (AP and lateral views) and four radiographic views (AP, lateral and both oblique views) in ankle fractures. Materials and Methods: From January 2000 to June 2002, 60 cases of ankle fractures were treated with open reduction and internal fixation and its followed up periods were at least 2 years. All cases were classified into three groups according to the method of preoperative radiographic evaluation. Two radiographic views (AP and lateral views) were taken in group A and four radiographic views (AP, lateral and both oblique views) were taken in group B. 12 Cases were evaluated with three dimensional computed tomography (3D CT). Four radiographic views and 3D CT were taken in group C. All cases were classified according to the Danis-Weber and Lauge-Hansen classification. Displacement of fracture fragment of medial, lateral, posterior malleolus and size of fracture fragment of posterior malleous were measured using picture archiving communication system (PACS). Results: Although kappa value between two or four radiographic views were good or excellent in Danis-Weber classification and Lauge-Hansen classification of ankle fractures, the displacements of medial and lateral malleoli were statistically different. Four radiographic views evalulated the degree of displacement of medial and lateral fragments more accurately compared to two radiographic views. Conclusion: Four radiographic views will be more useful than two radiographic views to decide the method of treatment and operation considering the displacement of fracture fragment.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1489-1495
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• 2012

In this study, we perform the structural analysis of a floating offshore wind turbine tower by considering the dynamic response of the floating platform. A multibody system consisting of three blades, a hub, a nacelle, the platform, and the tower is used to model the floating wind turbine. The blades and the tower are modeled as flexible bodies using three-dimensional beam elements. The aerodynamic force on the blades is calculated by the Blade Element Momentum (BEM) theory with hub rotation. The hydrostatic, hydrodynamic, and mooring forces are considered for the platform. The structural dynamic responses of the tower are simulated by numerically solving the equations of motion. From the simulation results, the time history of the internal forces at the nodes, such as the bending moment and stress, are obtained. In conclusion, the internal forces are compared with those obtained from static analysis to assess the effects of wave loads on the structural stability of the tower.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.4
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• pp.392-401
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• 2019

This study describes how the illustration book of Korean coastal and offshore fishing boats was published. The illustration book provides information on fisheries which need boats for their fishing operation. The book contains 25 fishing boats belonging to 15 offshore fisheries and six boats belonging to five coastal fisheries totalling 31 boats belonging to 20 kinds of fisheries. Until now, no books were available in Korea on fishing boats which provided illustrated descriptions of their use in fishing. We carried out field and literature surveys of fishing boats for three years (2016-2018) and the results were compiled into three-dimensional modeling images with schematic drawings of fishing boats, along with text explanations. The particulars and technical drawings of lines, general arrangement (GA), fishing gears and methods are collected and summarized. All fishing boats are modeled with 3D color graphics. The particulars and names of the main items of the fishing equipment are presented besides structural parts. In addition the fishing gear, fishing season and grounds, number of crews and target species for each boat are correctly described. The illustration book of Korean coastal and offshore fishing boats will contribute to understanding the current status of fishing techniques in Korea and will assist in developing new types of fishing boats.

• Journal of Digital Contents Society
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• v.18 no.4
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• pp.723-731
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• 2017

The restoration of archaeological data was carried out using photographs and drawings left as past records. It can be divided into ruins and artifacts. The restoration of the ruins was performed by modeling the individual parts and parts left by the photographs, aligning them and synthesizing them, and reconstructing them three-dimensionally as one object. Restoration of artifacts was performed on both photographs and drawings. After the modeling work is prioritized through the photographs, there is a method of restoring the original image by modifying the texture image of the damaged part of the modeled artifact, or restoring the original image by modeling and synthesizing the deleted part in the artifact. The restoration of the artifacts through the drawings was carried out by three - dimensional modeling and reconstruction through real mapping of images. The reconstructed archaeological data can be used in various directions. In particular, it is possible to verify and compare the results of the numerical analysis and interpretation of the past 2D data, and to provide a more accurate analysis plan in the future.

• Wind and Structures
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• v.34 no.6
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• pp.483-497
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• 2022

Three-dimensional (3D) computational fluid dynamics (CFD) analysis of flow around a hipped-roof building representative of UK inland conditions are conducted. Unsteady simulations are performed using three variations of the k-ϵ RANS turbulence model namely, the Standard, Realizable, and RNG models, and their predictive capability is measured against current European building standards. External pressure coefficients and wind loading are found through the BS 6399-2:1997 standard (obsolete) and the current European standards (BS EN 1991-1-4:2005 and A1:20101). The current European standard provides a more conservative wind loading estimate compared to its predecessor and the k-ϵ RNG model falls within 15% of the value predicted by the current standard. Surface shear stream-traces and Q-criterion were used to analyze the flow physics for each model. The RNG model predicts immediate flow separation leading to the creation of vortical structures on the hipped-roof along with a larger separation region. It is observed that the Realizable model predicts the side vortex to be a result of both the horseshoe vortex and the flow deflected off it. These model-specific aerodynamic features present the most disparity between building standards at leeward roof locations. Finally, pedestrian comfort and safety criteria are studied where the k-ϵ Standard model predicts the most ideal pedestrian conditions and the Realizable model yields the most conservative levels.

• Advances in concrete construction
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• v.14 no.3
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• pp.169-183
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• 2022

In this article, vibrational behavior and wave propagation characteristics in (FG) functionally graded plates resting on Kerr foundation with three parameters is studied using a 2D dimensional (HSDT) higher shear deformation theory. The new 2D higher shear deformation theory has only four variables in field's displacement, which means has few numbers of unknowns compared with others theories. The shape function used in this theory satisfies the nullity conditions of the shear stresses on the two surfaces of the FG plate without using shear correction factors. The FG plates are considered to rest on the Kerr layer, which is interconnected with a Pasternak-Kerr shear layer. The FG plate is materially inhomogeneous. The material properties are supposed to vary smoothly according to the thickness of the plate by a Voigt's power mixing law of the volume fraction. The equations of motion due to the dynamics of the plate resting on a three-parameter foundation are derived using the principle of minimization of energies; which are then solved analytically by the Navier technique to find the vibratory characteristics of a simply supported plate, and the wave propagation results are derived by using the dispersion relations. Perceivable numerical results are fulfilled to evaluate the vibratory and the wave propagation characteristics in functionally graded plates and some parameters such wave number, thickness ratio, power index and foundation parameters are discussed in detail.