• IE interfaces
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• v.16 no.spc
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• pp.87-92
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• 2003

Progressive mesh representation and generation have become one of the most important issues in network-based computer graphics. However, current researches are mostly focused on triangular mesh models. On the other hand, solid models are widely used in industry and are applied to advanced applications such as product design and virtual assembly. Moreover, as the demand to share and transmit these solid models over the network is emerging, the generation and the transmission of progressive solid models depending on specific engineering needs and purpose are essential. In this paper, we present a Cellular Topology-based approach to generating and transmitting progressive solid models from a feature-based solid model for internet-based design and collaboration. The proposed approach introduces a new scheme for storing and transmitting solid models over the network. The Cellular Topology (CT) approach makes it possible to effectively generate progressive solid models and to efficiently transmit the models over the network with compact model size.

• ETRI Journal
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• v.32 no.4
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• pp.530-539
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• 2010

As the conventional silicon metal-oxide-semiconductor field-effect transistor (MOSFET) approaches its scaling limits, quantum mechanical effects are expected to become more and more important. Accurate quantum transport simulators are required to explore the essential device physics as a design aid. However, because of the complexity of the analysis, it has been necessary to simulate the quantum mechanical model with high speed and accuracy. In this paper, the modeling of double gate MOSFET based on an adaptive neuro-fuzzy inference system (ANFIS) is presented. The ANFIS model reduces the computational time while keeping the accuracy of physics-based models, like non-equilibrium Green's function formalism. Finally, we import the ANFIS model into the circuit simulator software as a subcircuit. The results show that the compact model based on ANFIS is an efficient tool for the simulation of nanoscale circuits.

• Journal of Electrical Engineering and Technology
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• v.9 no.2
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• pp.649-654
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• 2014

In this paper, an analytical model for Surrounding Gate (SG) metal-oxide- semiconductor field effect transistors (MOSFETs) considering quantum effects is presented. To achieve this goal, we have used variational approach for solving the Poission and Schrodinger equations. This model is developed to provide an analytical expression for inversion charge distribution function for all regions of device operation. This expression is used to calculate the other important parameters like inversion charge density, threshold voltage, drain current and gate capacitance. The calculated expressions for the above parameters are simple and accurate. This paper also focuses on the gate tunneling issue associated with high dielectric constant. The validity of this model was checked for the devices with different dimensions and bias voltages. The calculated results are compared with the simulation results and they show good agreement.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.6
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• pp.531-537
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• 2016

The damage and fracture of machine or structure are caused by the crack happened from the defect existed at the inside of material. The properties of crack propagation and growth characteristic must be considered because there are many cases at which these cracks are densely existed. Therefore, this study investigates the fracture property due to the position of crack and hole inside the standard compact tension (C. T.) specimen. When the concentrated load is applied eccentrically at the standard C. T. specimen, the fracture mechanical behavior due to the existence or non-existence and the position of hole near crack is investigated. As the result of analysis study, model 3 (in case of the distance of 2mm on the horizontal direction between the end part and hole as the specimen model existed with one hole near the crack) has the maximum deformation, stress and deformation energy of the most values among three models. As the distance between the crack and hole inside the specimen becomes nearer, the maximum stress becomes higher in cases of three models. Apart from the number of holes, it is seen that the maximum stress becomes higher near the crack when the hole exists near the crack inside the specimen. If the hole inside the machine or the mechanical structure is punctured by using the result of this study, it is thought that the occurred breakage or breakdown can be prevented by reducing the fracture stress happened at the specimen.

• Journal of Internet Computing and Services
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• v.12 no.6
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• pp.73-82
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• 2011

The location-based service is emerging again to the public attention. The location recognition environment up-to-now has been studied with its focus only on a person, an object or a moving object. However, this study proposes a location recognition model that serves to recognize and track, in real time, multiple passengers in a moving vehicle. Identifying the locations of passengers can be classified into two classes: one is to use the high price terminal with GPS function, and the other is to use the economic price compact terminal without GPS function. Our model enables the simple compact terminal to provide effective location recognition under the on-boarding situation by transmitting messages through an interface device and sensor networks for a vehicle equipped with GPS. This technology reduces transmission traffic after detecting the condition of a vehicle (being parked or running), because it does not require transmission/receiving of information on the locations of passengers who are confined in a vehicle when the vehicle is running. Also it extends battery life by saving power consumption of the compact terminal. Hence, we carried out experiments to verify its serviceability by materializing the efficient tracking system for passengers with the detection algorithm of a stopping vehicle proposed in this study. Moreover, about 200 experiments using the system designed with this technology proved successful recognition on on-boarding and alighting of passengers with the maximum transmission distance of 12 km. In addition to this, the running recognition tests showed the test with the detection algorithm of a stopping vehicle has reduced transmission traffic by 41.6% compared to the algorithm without our model.

• Journal of Korean Society of Steel Construction
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• v.26 no.6
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• pp.581-594
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• 2014

In this paper, flexural resistance of hybrid girder under uniform bending moment was evaluated, which is composed of HSB800 and HSB600 steel for the flange and web, respectively. Doubly-symmetric and monosymmetric sections with noncompact or compact flange and slender, noncompact or compact web were considered. Nonlinear analyses with 3-dim. shell element model were performed to determine the 'flexural resistance of section' and the 'lateral torsional buckling strength' by taking initial imperfection and residual stress into account. The numerical results were compared with the AASHTO LRFD and Eurocode 3 specifications and also the applicability of AASHTO LRFD appendix A6 was examined for the sections with noncompact and compact web.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.1
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• pp.79-87
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• 2002

The purpose of this study was to investigate the color stability of composite resins used widely as esthetic restorative material. Surefil(Dentsply, U.S.A.), Esthet X(Dentsply, U.S.A.), Filtek P60(3M, U.S.A.) , Filtek Z250(3M, U.S.A.), Synergy Compact(Coltene, Switzerland), and Synergy Duo(Coltene, Switzerland) were chosen for this study. Thirty six specimens($7mm{\times}2mm$) of each composite resin were fabricated and polished after polymerization. Treatment conditions designed for this study were thermocycling, methylene blue staining, and filtered coffee staining. The color changes before and after treatment were measured by colorimeter(colorimeter, Model Tc-6Fx, Tokyo Denshoku Co.) and analyzed. The followings were drawn from this study: 1. The color changes of Filtek Z250, Surefil, Filtek P60 and Esthet X after thermocycling for 3 weeks were greater than those of the others. 2. The color changes of Surefil and Esthet X after methylene blue stainig and those of Surefil, Filtek Z250 and Filtek P60 after coffee staining were great. 3. The color changes or Synergy Duo and Synergy Compact after thermocycling and coffee staining were relatively lesser than those of other composite resins.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.3
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• pp.589-596
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• 2018

Transportation or structure has the important role at clothing, food, and housing at modern society. If even the small crack happens and propagates at transportation or structure, the parts are fractured and they can cause a disaster. CT specimen was used in order to investigate the damage trend due to the crack propagation at this study to prevent this situation. As the material of CT specimen, the unidirectional carbon fiber reinforced plastic of the composite material in the limelight nowadays. The laminate angle designated in order of [60/-60/60/-60] was applied to the specimen model with the unidirectional fiber. As the analysis condition, the forced displacement was applied to the hole of upper part after fixing the hole of lower part. At the result of this study, the equivalent stress and shear stress was shown to be higher in order of the structural steel, copper, titanium and aluminum. This study result is thought to be utilized usefully at verifying the damage of CT specimen made of inhomogeneous material.

• International Journal of Reliability and Applications
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• v.1 no.2
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• pp.123-131
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• 2000

This paper concerns with the consistent estimator for the fuzzy expectation of a random variable taking values in the space F($R^p$) of upper semicontinuous convex fuzzy subsets of $R^p$ with compact support. We introduce the concept of a fuzzy sample mean and show that the fuzzy sample mean is a strong consistent estimator for the fuzzy expectation. Some examples are given to illustrate the main result.

• Proceedings of the IEEK Conference
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• 2000.06b
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• pp.262-265
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• 2000

This paper describes design of a (32, 28) Reed Solomon decoder for optical compact disk provides double error detecting and correcting capability. The most complex circuit in the RS decoder is part for solving the error location numbers from error location polynomial, and the circuit has great influence on overall decoder complexity. We use RAM based architecture with Euclid algorithm, Chien search algorithm and Forney algorithm. We have developed VHDL model and Performed logic synthesis using the SYNOPSYS CAD tool. Then, the RS decoder has been implemented with FPGA. The total umber of gate is about 11,000 gates and it operates at 20MHz.