• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.45 no.6
• /
• pp.369-373
• /
• 2019

This paper describes a patient with an insufficient vestibular depth for a removable partial denture who underwent vestibuloplasty with a free gingival graft using a titanium mesh in the anterior mandible. Free gingiva was harvested from the palatal mucosa, and a partial thickness flap was elevated at the recipient site. After minimal suturing for the graft, a titanium mesh was fixed over the graft. The mesh was removed four weeks after surgery. The patient obtained an adequate vestibular depth and keratinized gingiva eight weeks after surgery without any complications. In this case, an appropriate vestibular depth and keratinized gingiva were easily obtained by vestibuloplasty using a titanium mesh.

• Journal of the Semiconductor & Display Technology
• /
• v.18 no.4
• /
• pp.100-104
• /
• 2019

The 'ITO/Ag/ITO' multilayers as a highly conductive and transparent electrode, even with the optimum thickness conditions, the transmittances were much lower than those of a single ITO layer on some ranges of the visible wavelength. In order to improve the transmittance, Ag layer was formed with mesh structure. Where, the thickness of the Ag layer was about 10 nm and the space between the Ag lines was varied from 2.9 ㎛ to 19.6 ㎛ with the fixed Ag width of about 1.2 ㎛ in order to vary an open ratio of the Ag mesh structure. The transmittance and sheet resistance in the ITO/Mesh-Ag/ITO multilayer structure were analyzed depending on the open ratio. As a result, a trade off in the open ratio was necessary in order to obtain the transmittance as high as possible and the sheet resistance as possible low. By the open ratio of about 86%, in the ITO/Mesh-Ag/ITO multilayer structure, the transmittance was nearly same as the single ITO layer and the sheet resistance was about 62.3 Ω/.

• Nuclear Engineering and Technology
• /
• v.50 no.3
• /
• pp.327-339
• /
• 2018

This article presents a new global-local hybrid coarse-mesh finite difference (HCMFD) method for efficient parallel calculation of pin-by-pin heterogeneous core analysis. In the HCMFD method, the one-node coarse-mesh finite difference (CMFD) scheme is combined with a nodal expansion method (NEM)-based two-node CMFD method in a nonlinear way. In the global-local HCMFD algorithm, the global problem is a coarse-mesh eigenvalue problem, whereas the local problems are fixed source problems with boundary conditions of incoming partial current, and they can be solved in parallel. The global problem is formulated by one-node CMFD, in which two correction factors on an interface are introduced to preserve both the surface-average flux and the net current. Meanwhile, for accurate and efficient pin-wise core analysis, the local problem is solved by the conventional NEM-based two-node CMFD method. We investigated the numerical characteristics of the HCMFD method for a few benchmark problems and compared them with the conventional two-node NEM-based CMFD algorithm. In this study, the HCMFD algorithm was also parallelized with the OpenMP parallel interface, and its numerical performances were evaluated for several benchmarks.

• Nuclear Engineering and Technology
• /
• v.51 no.5
• /
• pp.1181-1194
• /
• 2019

A new moving-mesh Finite Volume Method (FVM) for the efficient solution of the two-dimensional neutron diffusion equation is introduced. Many other moving-mesh methods developed to solve the neutron diffusion problems use a relatively large number of sophisticated mathematical equations, and so suffer from a significant complexity of mathematical calculations. In this study, the proposed method is formulated based on simple mathematical algebraic equations that enable an efficient mesh movement and CV deformation for using in practical nuclear reactor applications. Accordingly, a computational framework relying on a new moving-mesh FVM is introduced to efficiently distribute the meshes and deform the CVs in regions with high gradient variations of reactor power. These regions of interest are very important in the neutronic assessment of the nuclear reactors and accordingly, a higher accuracy of the power densities is required to be obtained. The accuracy, execution time and finally visual comparison of the proposed method comprehensively investigated and discussed for three different benchmark problems. The results all indicated a higher accuracy of the proposed method in comparison with the conventional fixed-mesh FVM.

• Journal of Aerospace System Engineering
• /
• v.17 no.2
• /
• pp.9-15
• /
• 2023

The task of generating a reduced thermal model of a satellite must be performed at least once in a satellite project to shorten the time of orbital thermal analysis and perform thermal analysis coupled to a launch vehicle. Although there are various methods for generating a reduced thermal model, an intuitive and convenient iso-thermal mesh generation method is used the most widely in practice. However, there is still a lack of research on automation of the isothermal mesh generation method. In this paper, we proposed an automated generation method of satellite reduced thermo-mathematical model based on the isothermal mesh generation method considering temperature tolerance and fixed nodes. The proposed method was validated using three different temperature tolerance cases. The average temperature difference satisfied the guidelines of ECSS.

• Journal of IKEEE
• /
• v.13 no.1
• /
• pp.94-100
• /
• 2009

In recent years, the wireless mesh network (WMN) has been an emerging technology to provide Internet access to fixed and mobile wireless devices. The main goal of this paper is the design and simulation of a new MAC protocol based on the multi-path routing information for wireless mesh networks. The information about multiple paths discovered in the network layer is exploited by the MAC layer in order to forward a frame over the best hop out of multiple hop choices. The performance of our approach is compared with conventional 802.11 MAC through the simulation. The results show that our scheme exhibits a significantly better performance rather than conventional 802.11 MAC protocol in terms of packet overhead, end-to-end throughput and delay.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.28 no.1
• /
• pp.43-50
• /
• 2010

The 200mesh screen was tensioned and fixed on a frame. When applied tension to 5N and 10N per unit area, a side length of opening of the screen was 163.223${\mu}m$ and 168.224${\mu}m$, respective. But side length not tensioned was 158.879${\mu}m$. We knew that a side length of opening of the screen rarely changes with tension applied to the screen. The appearances that a side length of opening of the screen expand little are due to a decreasing diameter of thread by means of tension. In a thickness measurement of screen, While the high density mesh screen that had a lot of knots that crossed a line of latitude and longitude per unit area appeared a higher numerical value, the low density mesh screen that had a few knots appeared a low numerical value.

• Proceedings of the Korea Contents Association Conference
• /
• 2007.11a
• /
• pp.248-251
• /
• 2007

In this paper, we are propose a method to estimate the 2-D mesh from structured light image for reconstruction of 3-D face image. To acquire the structured light image, we are project structured light on the face using the projector. we are extract the projected cross points from the acquire image. The 2-D mesh image is extracted from the position and angle of cross points. In the extraction processing, the error was fixed to extract the correct 2-D mesh.

• Management Science and Financial Engineering
• /
• v.6 no.2
• /
• pp.29-45
• /
• 2000

We consider the design of a two-level telecommunication network having logical full-mesh/star topology, with the implementation of conduit systems taken together. The design problem is then viewed as consisting of three subproblems: locating hub facilities, placing a conduit network, and installing cables therein to configure the logical full-mesh/star network. Without partitioning into subproblems as done in the conventional approach, the whole problem is directly dealt with in a single integrated framework, inspired by some recent successes with the approach. We successfully formulate the problem as a variant of the classical multicommodity flow model for the fixed charge network design problem, aided by network augmentation, judicious commodity definition, and some flow restrictions. With our optimal model, we solve some randomly generated sample problems by using CPLEX MIP program. From the computational experiments, it seems that our model can be applied to the practical problem effectively.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.4
• /
• pp.445-450
• /
• 2002

A series of 29 sampling with a 330 ${\mu}$m and a 64 ${\mu}$m mesh size of nets was conducted at a fixed station in Ilkwang Bay, southeast cost of Korea, from Oct, 2, 1991 to Oct. 10, 1992, to investigate the effects of mesh size of nets on biomass estimation of copepod Acartia steueri. The catch of copepodite and nauplius stages of A. steueli taken by two nets with different mesh size was different, showing that all developmental stages of A. steueri were retained on the 64 ${\mu}$m mesh net, but only $\geq$stage 4 copepodite were caught by the 330 ${\mu}$m mesh net. Abundance and biomass in each developmental stage estimated with the 64 ${\mu}$m mesh net were significantly higher than those of the 330 ${\mu}$m mesh net, except for adult female and stage 5 copepodite in female. The body length as well as the body width is likely to affect the catch of the nets. The mean biomass of A. steueli estimated with the traditional 330 ${\mu}$m net was 2.8 times lower than the value obtained with the 64 ${\mu}$m mesh net. However, the seasonal patterns of the biomass were comparable. These results suggest that accurate sampling strategr of the entire copepods assemblage including nauplii and copepodites are essential when estimating the abundance and biomass of copepods for the better understanding of the role of copepods in marine ecosystem.