• Journal of the Optical Society of Korea
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• v.20 no.5
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• pp.541-546
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• 2016

In this paper, by using the Rayleigh-Sommer field theory and the cross-spectral density function, the analytical expression for the intensity distribution of a double half-Gaussian hollow beam in a turbulent atmosphere is obtained. The influence of the initial spot size of this beam on its propagation properties in a turbulent atmosphere is simulated, and the intensity distributions for such beams with different spot sizes are obtained. The results show that the initial spot size has an important influence on the propagation properties in the near field, while this influence in the far field is very weak.

• Journal of information and communication convergence engineering
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• v.10 no.2
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• pp.200-204
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• 2012

This study has presented the analysis of breakdown voltage for a double-gate metal-oxide semiconductor field-effect transistor (MOSFET) based on the doping distribution of the Gaussian function. The double-gate MOSFET is a next generation transistor that shrinks the short channel effects of the nano-scaled CMOSFET. The degradation of breakdown voltage is a highly important short channel effect with threshold voltage roll-off and an increase in subthreshold swings. The analytical potential distribution derived from Poisson's equation and the Fulop's avalanche breakdown condition have been used to calculate the breakdown voltage of a double-gate MOSFET for the shape of the Gaussian doping distribution. This analytical potential model is in good agreement with the numerical model. Using this model, the breakdown voltage has been analyzed for channel length and doping concentration with parameters such as projected range and standard projected deviation of Gaussian function. As a result, since the breakdown voltage is greatly changed for the shape of the Gaussian function, the channel doping distribution of a double-gate MOSFET has to be carefully designed.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• v.5B no.3
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• pp.258-261
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• 2005

The Preisach model needs a distribution function or Everett function to simulate the hysteresis phenomena. To obtain these functions, many experimental data obtained from the first order transition curves are usually required. In this paper, a simple procedure to determine the Preisach density function using the Gaussian distribution function and genetic algorithm is proposed. The Preisach density function for the interaction field axis is known to have Gaussian distribution. To determine the density and distribution, genetic algorithm is adopted to decide the Gaussian parameters. With this method, just basic data like the initial magnetization curve or saturation curves are enough to get the agreeable density function. The results are compared with experimental data and we got good agreements comparing the simulation results with the experiment ones.

• Korean Journal of Optics and Photonics
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• v.16 no.2
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• pp.152-158
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• 2005

We investigated the operational characteristics of a Q-switched Nd:YAG laser, which has an unstable resonator with a GRM(Gaussian reflectivity mirror). With electrical input energy of 55 J, we obtained the fundamental energy of 470 mJ at 1064 nm and the frequency doubled energy of 280 mJ at 532 nm. The Top-Hat profile of the output beam was obtained at the near field, and beam divergence was 1.7 mard.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.3
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• pp.113-123
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• 2007

This paper presents a high-performance elliptic curve cryptographic processor over $GF(2^m)$. The proposed design adopts Lopez-Dahab Montgomery algorithm for elliptic curve point multiplication and uses Gaussian normal basis for $GF(2^m)$ field arithmetic operations. We select m=163 which is the smallest value among five recommended $GF(2^m)$ field sizes by NIST and it is Gaussian normal basis of type 4. The proposed elliptic curve cryptographic processor consists of host interface, data memory, instruction memory, and control. We implement the proposed design using Xilinx XCV2000E FPGA device. Based on the FPGA implementation results, we can see that our design is 2.6 times faster and requires significantly less hardware resources compared with the previously proposed best hardware implementation.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.331.2-336
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• 1998

In this paper, the validity for the application of the diffuse sound field theoty to the real sound field, especially on the bounding surfaces of the rooms, was reconsidered. The analytical result for directivity pattern on the bounding surfaces of the room was compared with the result of numerical simulations using ray tracing technique. Comparison results show that the distribution of the incident sound energy vs incident angles is approximated to Gaussian distribution, not to the uniform distribution.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.5
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• pp.539-544
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• 2000

A simple analytic model is proposed here to analyze the concentration deficit field caused by a large area of vegetated area. With non-dimensional deposition velocity chosen as small parameter, the regular perturbation method is exploited to derive the mass balance equation and the dynamic equations for the concentration deficit field, Analytic solutions to those equations are obtained in a closed form for several cases of interest, assuming that the concentration field is stationary and the plume can be nicely approximated as Gaussian for a point source. The results suggest that quite a negligible fraction (less than 1%) of the gaseous air pollutants emitted into the air is removed by the vegetated area of which width is 4 km in wind-wise direction, the typical dimension of the Restricted Development Zones around the metropolitan regions in South Korea.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.8 no.1
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• pp.18-27
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• 1996

Efforts are concentrated onto effective simulation of surface discharged heat water in two-dimensional depth-averaged finite element model using Gaussian puff algorithm incorporating near-field characteristics as patches computed from CORMIX3 with ambient flow variations. Concise analyses of horizontal and vertical temperature distributions are made for real coastal power plant discharges through four field observations and the results from this proposed method are in good agreements with observations in far-field as well as near-field. Thus, this method can simulate the heat dispersion effectively for the whole region since the complex jet momentum characteristics and ambient flows are easily represented in 10 meters of finite element discretization around a discharging point.

• ETRI Journal
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• v.7 no.4
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• pp.3-10
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• 1985

After the light from an incoherent LED was transmitted through the multimode fibers which were linked over 10 km, the nearfield power distribution reached the steady-state independent of launching conditions. It has been also found that the steady-state output power distribution showed the pattern of Gaussian function. In this steady-state Gaussian function pattern, the measured losses of fibers were very repeatable values. In case of using LD source, the speckle phenomena in near -field power distribution appeared until the distance of 10 km. And the output power distribution did not reach the steady-state shown in LED even over 20km on account of the coherence and the nonuniform lasing modes of LD. But the measured losses of fibers were nearly stable in this long distance.

• Kyungpook Mathematical Journal
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• v.57 no.4
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• pp.581-600
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• 2017

A classical result of A. Cohn states that, if we express a prime p in base 10 as $$p=a_n10^n+a_{n-1}10^{n-1}+{\cdots}+a_110+a_0$$, then the polynomial $f(x)=a_nx^n+a_{n-1}x^{n-1}+{\cdots}+a_1x+a_0$ is irreducible in ${\mathbb{Z}}[x]$. This problem was subsequently generalized to any base b by Brillhart, Filaseta, and Odlyzko. We establish this result of A. Cohn in $O_K[x]$, K an imaginary quadratic field such that its ring of integers, $O_K$, is a Euclidean domain. For a Gaussian integer ${\beta}$ with ${\mid}{\beta}{\mid}$ > $1+{\sqrt{2}}/2$, we give another representation for any Gaussian integer using a complete residue system modulo ${\beta}$, and then establish an irreducibility criterion in ${\mathbb{Z}}[i][x]$ by applying this result.