• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.453-456
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• 1999

The Si-SiO$_2$interface trap and nitride bulk trap distribution of SONOSFET(polysilicon-oxide-nitride-oxide-semiconductor)NVSM(nonvolatile semiconductor memory) cell were investigated by single charge pumping method. The used device was fabricated by 0.35 7m standard logic fabrication including the ONO cell process. This ONO dielectric thickness is tunnel oxide 24 $\AA$, nitride 74 $\AA$, blocking oxide 25 $\AA$, respectively. Keeping the pulse base level in accumulation and pulsing the surface into inversion with increasing amplitudes, the charge pumping current flow from the single junction. Using the obtained I$_{cp}$-V$_{h}$ curve, the local V$_{t}$ distribution, doping concentration, lateral interface trap distribution and lateral memory trap distribution were extracted. The maximum N$_{it}$($\chi$) of 1.62$\times$10$^{19}$ /cm$^2$were determined.mined.d.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.759-762
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• 2000

Present transistors which have vertical structure show increased parasitic capacitance characteristics in accordance with the increase of non-active base area and collector area, consequently have disadvantage for high speed switching performance. In this paper, a horizontal structure transistor which has minimized parasitic capacitance in virtue of SDB(Silicon Direct Bonding) wafer and oxide sidewall isolation utilizing silicon trench technology is presented. Its structural characteristics were designed by ATHENA(SUPREM4), the process simulator from SILVACO International, and its performance was proven by ATLAS, the device simulator from SILVACO International. The performance of the proposed horizontal structure transistor was certified through the VCE-lC characteristics curve, $h_{FE}$ -IC characteristics, and GP-plot.

• Transactions on Electrical and Electronic Materials
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• v.7 no.4
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• pp.173-179
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• 2006

Due to the limitations of the channel length, the lateral spread for two-dimensional impurity distributions is critical for the analysis of devices including the integrated complementary metal oxide semiconductor (CMOS) circuits and high frequency semiconductor devices. The developed codes were then compared with the two-dimensional implanted profiles measured by transmission electron microscope (TEM) as well as simulated by a commercial TSUPREM4 for verification purposes. The measured two-dimensional TEM data obtained by chemical etching-method was consistent with the results of the developed analytical model, and it seemed to be more accurate than the results attained by a commercial TSUPREM4. The developed codes can be applied on a wider energy range $(1KeV{\sim}30MeV)$ than a commercial TSUPREM4 of which the maximum energy range cannot exceed 1MeV for the limited doping elements. Moreover, it is not only limited to diffusion process but also can be applied to implantation due to the sloped and nano scale structure of the mask.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.6
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• pp.401-415
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• 1989

A simple but accurate analytical model for the lateral channel electric field in gate-offset structured Lightly Doped Drain MOSFET has been developed. Our model assumes Gaussian doping profile, rather than simple uniform doping, for the lightly doped region and our model can be applied to LDD structures where the junction depth of LDD is not identical to the heavily doped drain. The validity of our model has been proved by comparing our analytical results with two dimensional device simulations. Due to its simplicity, our model gives a better understanding of the mechanisms involved in reducing the electric field in the LDD MOSFET. The model shows clearly the dependencies of the lateral channel electric field on the drain and gate bias conditions and process, design parameters. Advantages of our analytical model over costly 2-D device simulations is to identify the effects of various parameters, such as oxide thickness, junction depth, gate/drain bias, the length and doping concentration of the lightly doped region, on the peak electric field that causes hot-electron pohenomena, individually. Our model can also find the optimum doping concentration of LDD which minimizes the peak electric field and hot-electron effects.

• Advances in aircraft and spacecraft science
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• v.6 no.5
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• pp.371-389
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• 2019

The implementation of a robust $H_{\infty}$ Control, which is numerically efficient for uncertain nonlinear dynamics, on longitudinal and lateral autopilots is realised for a quarter scale Piper J3-Cub model accepted as an unmanned aerial vehicle (UAV) under the condition of sensor noise and disturbance effects. The stability and control coefficients of the UAV are evaluated through XFLR5 software, which utilises a vortex lattice method at a predefined flight condition. After that, the longitudinal trim point is computed, and the linearization process is performed at this trim point. The "${\mu}$-Synthesis"-based robust $H_{\infty}$ control algorithm for roll, pitch and yaw displacement autopilots are developed for both longitudinal and lateral linearised nonlinear dynamics. Controller performances, closed-loop frequency responses, nominal and perturbed system responses are obtained under the conditions of disturbance and sensor noise. The simulation results indicate that the proposed control scheme achieves robust performance and guarantees stability under exogenous disturbance and measurement noise effects and model uncertainty.

• Coupled systems mechanics
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• v.11 no.1
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• pp.1-14
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• 2022

The key parameter that affects the consolidation process of soil is the coefficient of permeability. The common assumption in the consolidation analysis is that the coefficient of permeability is porosity-dependent. However, various authors suggest that the strain-dependency of the coefficient of permeability should also be taken into account. In this paper, we present results of experimental and numerical analyses, with an aim to determine the strain-dependency of the coefficient of permeability. We present in detail both the experimental procedure and the finite element formulation of the two-dimensional axisymmetric numerical model of the oedometer test (standard and modified). We perform a set of experimental standard and modified oedometer tests. We use these experimental results to validate our numerical model and to define the model input parameter. Finally, by combining the experimental and numerical results, we propose the expression for the strain-dependent coefficient of permeability.

• Clinical Pain
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• v.18 no.2
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• pp.115-120
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• 2019

Acute calcific tendinitis (ACT) is a benign painful inflammatory disorder characterized by resorptive process of calcific deposits following the formation of calcium hydroxyapatite crystals in the tendons. It can occur at various sites, especially in the shoulder or hip joint. ACT involving the lateral epicondyle of the humerus and the cervical spine is very rare. Few reports have demonstrated successive ACT at different sites. We report three cases of successive ACT in women, occurring at the subscapularis followed by the lateral epicondyle, flexor carpi ulnaris followed by the supraspinatus, and longus colli followed by the iliopsoas, respectively.

• Journal of Welding and Joining
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• v.28 no.5
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• pp.69-74
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• 2010

Irradiation behavior of the reactor pressure vessel SA508 class 3 steel weld metals was examined by Charpy V Notch impact specimens. The specimens were exposed to a fluence of $2.8{\times}1019$ neutrons(n)/$cm^2$(E>1 MeV) at $288^{\circ}C$. The irradiation damage of weld metal was evaluated by comparison between unirradiated and irradiated specimens in terms of absorbed energy and lateral expansion. The specimens for neutron irradiation were welded by submerged arc welding process at a heat input of 3.2 kJ/mm which showed good toughness in terms of weld microstructure, absorbed energy and lateral expansion. The post-irradiation Charpy V notch 41J and 68J transition temperature elevation were $65^{\circ}C$ and $70^{\circ}C$, respectively. This elevation was accompanied by a 20% reduction in Charpy V notch upper shelf energy level. The lateral expansion at 0.9mm irradiated Charpy specimens showed temperature elevation of $65^{\circ}C$ and was greatly decreased due to radiation damage.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09b
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• pp.171-180
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• 2010

In this study, applicability of software used to analyze the lateral deformations and its shape of braced cuts, executed to excavate the ground for constructing the underground structures, was assessed by performing field measurements and numerical analyses and their behaviors were also compared with results of previous studies. Three typical sections, located at the construction site where the subway was on the process of construction at Suwon city in Gyeonggido, were chosen and the data of field measurement at those sections were collected. Numerical analyses with FEM technique of using the software PLAXIS and elasto-plastic approach of using the software MIDAS were performed. In general, the deformed shapes of braced cut, obtained from numerical approaches, were in relatively good agreements with results from field measurements. For sections of A-A and B-B, measured values were greater than analyzed ones whereas they were in relatively good agreements in the section C-C. As results of comparing the values from the measurements and the estimations, they were found to be close to each other so that numerical approaches were assessed to be appropriate to estimate the lateral deformation. The numerical technique with FEM was preferred to use because it estimated closer to the measurements than the elasto-plastic approach.

• Korean Journal of Cleft Lip And Palate
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• v.3 no.2
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• pp.41-50
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• 2000

The alar base on the cleft side in unilateral complete cleft lip, alveolus and palate is markedly displaced laterally, caudally and dorsally, By incising the pyriform margin from the cleft margin of the alveolar process, including mucosa of the anterior part of the inferior turbinate, to the upper end of the postnasal vestibular fold, the alar base is released from the maxilla, A physiological correction of nasal deformity can be accomplished by careful reconstruction of nasolabial muscle integrity, functional repair of the orbicular muscle, raising and rotating the displaced alar cartilage, and finally by lining the lateral nasal vestibule, The inferior maxillary head of the nasal muscle complex is identified as the deeper muscle just below the web of the nostril, The muscle is repositioned inframedially, so that it is sutured to the periosteum that overlies the facial aspect of the premaxilla in the region of the developing lateral incisor tooth, And then, the deep superior part of the orbicular muscle is sutured to the periosteum and the fibrous tissue at the base of the septum, just in front of the anterior nasal spine, The nasal floor is surgically created by insertions of the nasal muscle complex in deep plane and of the orbicular muscle in superficial one, The upper part of the lateral nasal vestibular defect is sutured by shifting the alar flap cephalically, The middle and lower parts of this defect are closed by use of cleft margin flaps of the philtral and lateral segments, respectively, Authors stress the importance of nasal floor reconstruction at primary surgery and report the technique and postoperative results.