몬테카를로 방법에 의한 수소분자의 기저상태 에너지의 수치 해석적인 계산

양해정,양회룡,정진,김미정,최승평,장차익 조선대학교 기초과학연구소 2000 自然科學硏究 Vol.23 No.1

Numerical methods that are known as Monte as Monte Carlo methods can be loosely described as statistical simulation methods, where statistical simulation is defined in quite general terms to be any method that utilizes sequences of random numbers to perform the simulation. Monte Carlo methods are now used routinely in many problems, the simulation of the esoteric subnuclear processes in high energy physics experiments, cellular automata, self-organized critical phenomena, the Ising spin glass, the simulation of a Bingo game, etc. The physical processes are simulated directly, and there are no needs to even write down the differential equations that describe the behaviors of the systems. The only requirement is that the physical systems be described by probability density functions. We consider with the Monte Carlo variational method and the Monte Carlo path integral method(MCPI). These methods are used to calculate the energy of the ground states of H2 molecule by the formal similarity between the Schroedinger equation and the multi-dimensional diffusion equation.

He 원자의 가장 낮은 들뜬 상태 에너지의 수치 계산

차혁렬,양해정,김미정,정진,양회룡,최승평,장차익 조선대학교 기초과학연구소 1999 自然科學硏究 Vol.22 No.1

The one-electron theory of atoms, molecules, and crystals have enjoyed a wide success in many branches of physics. This theory provides a physically appealing description of the electronic structure of many-electron systems. In addition, this theory gives a convenient basis for performing the detailed calculation on specific many-electron systems. In such calculations, it is usually necessary to introduce many simplified assumptions in order to make a progress. Since the principal computational difficulty supposed by the Hartree-Fock equations is the treatment of the exchange term, it would be very desirable to simplify the treatment of these terms by using Slater's average of the exchange potential. The first order correction of energy in the lowest excited states of He atom is calculated by using the unperturbed wave function obtained with the Hartree-Fock-Slater approximation and compared with the result obtained by the simple analytical method. The numerical results agrees with an experimental results for the lowest excited states of He atom with tolerance 3.22%, 2.16%, 2.94% and 3.41%. These results show that the numerical analysis can be applied to other multielectron atoms with the personal computer.

교차로 신호 주기의 실시간 제어를 위한 FUZZY 무게 중심법의 적용에 관한 연구

정진용,박효영 順天靑巖大學 1996 論文集-順天靑巖大學 Vol.20 No.1

Because of continuous change of traffic patterns and increase in traffic volume, effective signal traffic systems should require signal system. Which can flexibly manage road situations that have been changed every hours. In this paper, we study system that can control the intersection signal autonomously with the analysis of situations related to intervals of inter-section signal and traffic volume. We propose the method that fuzzy logic controller(FLC) which is applied to fuzzy logic control traffic signal. In order to prove higher performance of the FLC presented in this paper, We have compared the regular signal systems with fuzzy signal systems.

동시회전 정식화를 이용한 트러스 구조의 비선형 거동 해석

鄭會民,韓秉基 弘益大學校 科學技術硏究所 1999 科學技術硏究論文集 Vol.10 No.1

In the present study, it is considered both geometrical and material nonlinearity for the analysis of the structures, and compared with the singular point position of the elastic and elasto-plastic behavior. The formulation methods use Total Lagrangian formulation. Updated Lagrangian formulation, corotational formulation. The elasto-plastic analysis apply the incremental stress-strain method, radial return algorithm, and piecewise linear method with the experimental data. The method applied go find the singular points combines the arc-length continuation method and the extended system. In the geometrical nonlinear analysis, corotational formulation is tested with the benchmark problems which include the large strain. The elasto-plastic analysis to solve the approximate solution without iteration process introduce the strain function which compared with the effective strain and the experimental data. It is compared with the singular points location of the elastic behavior and that of the elasto-plastic behavior. In the present study, it find the basically information that the difference among the formulation methods, the effect of the elastic and elasto-plastic behavior, and the position of the singular points have a affect the buckling behavior of structures.

모델원자들에 의한 전자 산란 단면적 계산

정진,양회룡,최승평,장차익 조선대학교 기초과학연구소 1998 自然科學硏究 Vol.21 No.1

The scattering cross section in model atom is the physical quantity which is susceptible of a reasonably direct experimental measurement and which at the same time lends itself readily to calculation, and which establish contact between scattering theory and scattering experiment to assist each other. We have calculated the differential cross section and total cross sections of electrons by targets which are Cu, S, He, Ne, Ar on the ground state without the targets distortion with the Born approximation and the Eikonal approximation. the electron energies are in the range up to about 1.3 ev∼10 kev. The potential used to represent the interaction between atom and electron in our calculation is the same as that is used by Lens-Jensen in the evaluation of the cross-sections. We used the Gauss Legndre quadrature for our numerical integration in our differential equations.

CVD-BN에서 poly-Si-SiO₂를 통하여 Si으로의 저농도 붕소확산

金正會,金鐵柱 서울市立大學校 1985 論文集 Vol.19 No.2

Low concentration (??10.16cm??) for boron diffusion was obtained by the diffusion into Si through poly·Si-SiO₂from CBD-BN (Chemical Vapor-Deposited Boron Nitride). Boron concentration distribution was defined by the two boundary diffusion model and any change of oxide layer originating this diffusion are not seen.

Isozyme Polymorphism에 의한 무 品種 標識 鑑別 硏究

禹永澮,朴大榮,李政明 경희대학교 부설 식량자원개발연구소 1991 硏究論文集 Vol.12 No.-

Identification of radish (Raphanus sativus) has been principally based on the phenotypes including flowering habit. As new cultivars are constantly being develped, the need for advanced and more reliable means of cultivar identification has been growing, particularly for the purpose of varietal protection and ensuring breeder's rights. This study was conducted to gather infomation on distinguishing cultivars using isozyme polymorphism by polyacrylamide gel electrophoresis(PAGE). PAGE performance was markedly affected by various factors such as gel concentration, slab gel thickness, glass plate size, running time, frequency of electrode buffer use, duration of sample storage, and others. AcPH, EST(1ow pH buffer system) and PGM isozyme could be used for testing the purity of a given hybrid but were not suitable for the precise cultivar identification. Among the 11 isozymes investigated, esterase(EST, high pH buffer system) isozyme gave clear differences in banding pattern depending upon cultivars but not between individual plants within a same cultivar.

상추種子 活力의 生化學的 評價硏究 : Ⅰ. Ethylene生成 Ⅰ. Ethylene Evolution

禹永澮,朴大榮,李政明 경희대학교 부설 식량자원개발연구소 1992 硏究論文集 Vol.13 No.-

Studies were conducted to find out relationship between the vigor of lettuce and the production of ethylene from germinating seeds of i5 cultivars and lines at 3 different temperatures. The effect of red light illumination and the effect of ACC (1-aminocyclopropane-1-carboxylic acid) and red light on seed germination and ethylene production were also investigated. major results can be summarized a s follows. 1. The lettuce seeds with greater ability of producing ethylene germinated better at high temperatures (25 and 30℃). Highly significant, positive correlations were found between the ethylene evolution and the germination rate at both tested temperatures. 2. Red light treatment significantly increased ethylene evolution and the seed germination rate at 25℃. Treatment of ACC in addition to the red light illumination further increased the germination rate as compared to the red light treatment alone. 3. Red light treatment a t high temperatures was found to be effective in releasing the thermodormancy induced by high temperatures, but the effectiveness varied considerably depending upon the cultivars.

다발성 연조직 종괴를 동반한 급성 림프구성 백혈병의 증례 보고

장정용,허경회,이원진,허민석,이삼선,최순철 대한구강악안면방사선학회 2005 Imaging Science in Dentistry Vol.35 No.2

A 15-year-old patient, who had been diagnosed and treated as Burkitt cell type acute lymphoblastic leukemia (ALLL3) already, visited our department. He complained of gingival enlargement and loosening teeth 1 month ago. The clinical examination revealed anterior open bite, gingival enlargement, and nontender swelling particularly in molar regions of both jaws. Deep periodontal pockets and severe mobility was shown on most of the teeth. The panoramic radiographs showed severe bone destruction and extrusion of the molars. The contrast enhanced CT showed multiple enhanced mass and bone marrow obliteration in both jaws. Chemotherapy was done and the swelling was subsided at 1 month later. In conclusion, radiologic findings of leukemia with soft tissue mass, known as chloroma or granulocytic sarcoma, mimic those of lymphoma, so blood test may be needed for the final diagnosis.

우리나라 야생조류의 체내 납(Pb)과 카드뮴(Cd) 축척

김정수,신주렬,이화수,구태회 경희대학교 2006 環境硏究 論文集 Vol.15 No.-

This study presents concentrations of lead and cadmium in liver and kidney in Korean wild birds during 2000-2002. Lead concentrations in livers were Kharadriiformes < Anserifoimes < Kiconiiformes < Falconiformes < Passeriformes < Columbiformes. Their lead concentrations in livers and kidneys was within background level and exposed level. Cadmium concentrations in kidneys were Kharadriiformes < Ciconiiformes < Anseriformes < Falconiformes < Passeriformes < Columbifoimes. Kidney cadmium concentrations in Korean wild birds were within the range of background level, but one Cattle Egret Bibulous ibis and 7 Ancient Murrelet Synthliboramphus antiques was toxic level.