• Nuclear Engineering and Technology
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• v.39 no.6
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• pp.717-724
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• 2007

A measurement-based time-domain noise simulation of radiation detector-preamplifier (front-end) noise in nuclear spectroscopy is described. The time-domain noise simulation was performed by generating "noise random numbers" using Monte Carlo's inverse method. The probability of unpredictable noise was derived from the empirical cumulative distribution function via the sampled noise, which was measured from a preamplifier output. Results of the simulated noise were investigated as functions of time, frequency, and statistical domains. Noise behavior was evaluated using the signal wave-shaping function, and was compared with the actual noise. Similarities between the response characteristics of the simulated and the actual preamplifier output noises were found. The simulated noise and the computed nuclear pulse signal were also combined to generate a simulated preamplifier output signal. Such simulated output signals could be used in nuclear spectroscopy to determine energy resolution degradation from front-end noise effect.

• Journal of Powder Materials
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• v.15 no.2
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• pp.87-94
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• 2008

In order to investigate a nitriding process of spent oxide fuel and the subsequent change in thermal properties after nitriding, simulated spent fuel powder was converted into a nitride pellet with simulated fission product elements through a carbothermic reduction process. Nitriding rate of simulated spent fuel was decreased with increasing of the amount of fission products. Contents of Ba and Sr in simulated spent fuel were decreased after the carbothermic reduction process. The thermal conductivity of the nitride pellet was decreased by an addition of fission product element but was higher than that of the oxide fuel containing fission product elements.

• Structural Engineering and Mechanics
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• v.18 no.3
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• pp.343-362
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• 2004

Rocking response of rigid bodies with rectangular footprint, freely standing on horizontal rigid plane is studied analytically. Bodies are subjected to simulated single component of horizontal earthquakes. The effect of baseline correction, applied to simulated excitations, on the rocking response is first examined. The sensitiveness of rocking motion to the details of earthquakes and geometric properties of rigid bodies is investigated. Due to the demonstrated sensitivity of rocking response to these factors, prediction of rocking stability must be made in the framework of probability theory. Therefore, using a large number of simulated earthquakes, the effects of duration and shape of intensity function of simulated earthquakes on overturning probability of rigid bodies are studied. In the case when a rigid body is placed on any floor of a building, the corresponding probability is compared to that of a body placed on the ground. For this purpose, several shear frames are employed. Finally, the viability of the energy balance equation, which was introduced by Housner in 1963 and widely used by nuclear power industry to estimate the rocking stability of bodies, is evaluated. It is found that the equation is robust. Examples are also given to show how this equation can be used.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.3
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• pp.237-243
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• 1992

To determine effects of simulated acid rain on the growth and yield of rice, soybean and sesame, and on the soil acidity, two cultivars of rice, soybean and sesame were exposed twice a week to one of four simulated rain acidities[pH 2. 6, 3. 6, 4. 6 and 5. 6(control)]. The plants were protected from ambient rain by a polyethylene film cover. No visible damage due to the simulated acid rain was observed at any stage of growth for either of the crops. In rice, heading date, plant height and yield components except ripening ratio were not significantly affected by the pH ofsimulated rain, but the ripening ratio and rough rice yield linearly decreased as the pH of simulated rain was decreased. In soybean, maturing date and yield components except 100 seed weight were not significantly influenced by the pH of simulated rain, but the 100 seed weight and yield linearly decreased as the pH of simulated rain was decreased. Seed yield and the other agronomic characteristics of sesame were not significantly affected by the pH of simulated rain. Soil pH after cropping rice, soybean and sesame decreased as pH of simulated rain was decreased.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.939-944
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• 2001

Genetic algorithm is modelled on natural evolution and simulated annealing is based on the simulation of thermal annealing. Both genetic algorithm and simulated annealing are stochastic method. So they can find global optimum values. For compare efficiency of SA and GA's, some function value was maximized. In the result, that was a little better than GA's.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.522-527
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• 2004

Resealed Simulated Annealing (RSA) has been devised for improving the disadvantage of Simulated Annealing (SA) which require tremendous amount of computation time. RSA and SA have been for optimization of satellite structures and for comparison of results from two algorithms. As a practical application, a satellite structure is optimized by the two algorithms. Weights of satellite upper platform and propulsion module are minimized. MSC/NASTRAN is used for the static and dynamic analysis. The optimization results of the RSA are compared with results of the classical SA. The numbers of optimization iterations could be effectively reduced by the RSA.

• Steel and Composite Structures
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• v.8 no.6
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• pp.475-490
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• 2008

A hybrid tabu-simulated annealing algorithm is proposed for the optimum design of steel frames. The special character of the hybrid algorithm is that it exploits both tabu search and simulated annealing algorithms simultaneously to obtain near optimum. The objective of optimum design problem is to minimize the weight of steel frames under the actual design constraints of AISC-LRFD specification. The performance and reliability of the hybrid algorithm were compared with other algorithms such as tabu search, simulated annealing and genetic algorithm using benchmark examples. The comparisons showed that the hybrid algorithm results in lighter structures for the presented examples.

• Journal of Korea Society of Digital Industry and Information Management
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• v.5 no.4
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• pp.69-76
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• 2009

High-speed services and bulk transmission were available by the development of the network and communication technologies. Moreover various next-generation converged services are undergoing a change by various services. This paper presents improved real-time simulated traffic generation and verification schemes based on the actual traffic pattern analysis. For this, we analyzed traffic patterns of actual application system and generated simulated traffics. We also suggested scheme that verify similarity of simulated traffic and actual traffic.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.4
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• pp.371-378
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• 1999

This paper presents an efficient algorithm for loss reduction of distribution system by automatic sectionalizing switch operation in large scale distribution systems of radial type. Simulated Annealing algorithm among optimization techniques can avoid escape from local minima by accepting improvements in cost, but the use of this algorithm is also responsible for an excessive computation time requirement. To overcome this major limitation of Simulated Annealing algorithm, we may use advanced Simulated Annealing algorithm. All constaints are divided into two constraint group by using perturbation mechanism and penalty factor, so all trail solutions are feasible. The polynomial-time cooling schedule is used which is based on the statistics calculation during the search. This approaches results in saving CPU time. Numerical examples demonstrate the validity and effectiveness of the proposed methodology.

• Korean Journal of Medicinal Crop Science
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• v.28 no.3
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• pp.183-194
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• 2020

Background: This study investigated the effect of soil properties and soil bacterial community on early growth characteristics of wild-simulated ginseng (Panax ginseng C. A. Meyer) in coniferous and mixed forest experimental fields. Methods and Results: The soil bacterial community was analyzed using a high throughput sequencing technique (Illumina MiSeq sequencing). The relationship between the soil bacterial community, soil properties, and growth characteristics of wild-simulated ginseng were analyzed using principal coordinate analysis (PCoA) and the Pearson's correlation analysis. Soil properties and soil bacterial community showed significant difference with forest physiognomy. Results of Pearson's correlation analysis and PCoA showed that the soil properties (soil pH, organic matter, total nitrogen, and cation exchange capacity) and soil bacterial community had significant correlation with tree species ratio and early growth characteristics of wild-simulated ginseng. Conclusions: This study clearly demonstrated the effect of soil properties and soil bacterial community on early growth characteristics of wild-simulated ginseng in coniferous and mixed forest. Moreover, these results will help in the selection of suitable cultivation sites for wild-simulated ginseng.