• Journal of Institute of Control, Robotics and Systems
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• v.12 no.5
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• pp.473-479
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• 2006

A global path planning algorithm using modified self-organizing feature map(SOFM) which is a method among a number of neural network is presented. The SOFM uses a randomized small valued initial weight vectors, selects the neuron whose weight vector best matches input as the winning neuron, and trains the weight vectors such that neurons within the activity bubble are move toward the input vector. On the other hand, the modified method in this research uses a predetermined initial weight vectors of the 2-dimensional mesh, gives the systematic input vector whose position best matches obstacles, and trains the weight vectors such that neurons within the activity bubble are move toward the opposite direction of input vector. According to simulation results one can conclude that the modified neural network is useful tool for the global path planning problem of a mobile robot.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.176-183
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• 2008

This paper highlights the importance of carrying out global slope stability analysis as part of design calculations for geosynethetic walls in tiered configuration. Four design case histories were selected to examine the appropriateness of their design by performing additional slope stability analyses using the shear strength reduction method with in the frame work of finite element analysis. The results indicated that all of the walls examined, which were designed to meet the current design guide lines, did not satisfy the global slope stability requirement, and that longer reinforcements are required in the upper tiers to achieve the minimum factor of safety. Practical implications of the findings are discussed.

• Journal of the Korean Physical Society
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• v.73 no.11
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• pp.1637-1643
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• 2018

To reduce the laser pulse shape distortion accompanying the amplification process and achieve an intended output pulse shape in the Nd:YAG amplifier chain, we propose a frequency-modulated pulse-amplification method. Assuming carrier-frequency-modulated seed pulses, we numerically simulate the pulse amplification in an Nd:YAG amplifier chain where severe distortion occurs. For the calculation, we develop a modified Frantz-Nodvik equation, which enables two inputs with different carrier frequencies. The simulation results indicate that the temporal contrast of the seed pulse needed to obtain a flat output pulse shape is reduced by 16 - 25 dB when frequency modulation is applied.

• Journal of Distribution Science
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• v.11 no.11
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• pp.49-55
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• 2013

Purpose - This study examined the effects of susceptibility to global consumer culture (SGCC) on the brand attitude of consumers of the global SPA brand in South Korea. Research Design, Data, and Methodology -Questionnaires were used, and the sample that was extracted by the convenience sampling method comprised 703 males and females, aged 20-36. The data were analyzed with SPSS 16.0 and Amos 5.0 for frequency analysis, exploratory factor analysis, confirmatory factor analysis, reliability analysis, correlation analysis, and structural equation modeling analysis. Results - First, conformity to consumption trends was found to have a significant effect on all four variables of SPA brand attitude (brand favorability, uniqueness, ethicality, and economic utility). Second, quality perception was found to have a significant effect on brand favorability, uniqueness, ethicality, and economic utility. Third, social prestige was found to have a positive effect on uniqueness. Conclusions - The results show that consumers' susceptibility to global culture is a significant factor in their attitude to the global SPA brand. Therefore, it would be more effective if the global SPA brand develops recognition among consumers that its products play a role in sharing new trends and global lifestyles.

• Proceedings of the KSRS Conference
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• 1998.09a
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• pp.3-8
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• 1998

Using GIS and socio-economical data the relationship between human activities and global environmental change Is Analysed from the view point of food productivity and CO2 emission. Under the assumption that the population problem, the food problem and global warming due to energy consumption can be stabilized through managing land use, impacts of human activities such as consumption of food, energy and timber on global environment changes, and global population capacity are Analysed using developed system dynamics model in the research. In the model the world is divided into two groups: OECD countries and the others. Used global land use data set Is land cover map derived from satellite data, and potential distribution of arable land is estimated by the method of Clamor and Solomon which takes into consideration spatial distribution of climate data such as precipitation and evapotranspiration. In addition, impacts of CO2 emission from human activities on food production through global warming are included in the model as a feedback. The results of the analysis for BaU scenario and Toronto Conference scenario are similar to the results of existing models. From the result of this study, the human habitability in 2020 is 8 billion people, and CO2 emission in 2020 based on BaU Scenario and on Toronto Scenario is 1.7 and 1.2 times more than the 1986's respectively. Improving spatial resolution of the model by using global data to distribute the environmental variables and sauce-economical indices is left for further studies.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.12 s.354
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• pp.68-74
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• 2006

The MANET(Mobile Ad Hoc Network) is an independent network that is oranized by only Mobile Hosts. MANET guarantees the mobility of the node and does not need a backbone network or a base station. Recently, there is a strong demand to connect MANET to the Internet. For the interconnection between MANET and Internet, Mobile hosts of MANET must have global IP address. The well known scheme of the address configuration for MANET is SAA(Stateless Address Autoconfiguration). SAA configurated IP address by node itself. The advantage of SAA is not requiring any server for address configuration. However the SAA has problems of unstable and inefficient interconnection on the AD Hoc Network. To solve this problem we propose a method that assigns an IPv6 Global address to the node through the Internet Gateway. The format of assigned IPv6 address is also defined. The simulation result demonstrates that the proposed method can support the host for fast getting of global IPv6 Address and Mobile IPv6 efficiently.

• Journal of Korea Technology Innovation Society
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• v.2 no.2
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• pp.266-274
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• 1999

The world market is being restructured into one global market. The globalization makes the competition m IT industry more vigorous. It is, therefore, the vital procedures that the selection of the promising items among IT equipment and the intensive investment on the selected items to gain the competitiveness in the area of IT global market. With these in mind, in this paper, we introduce a very systematic and objective method which appraises the promise of IT equipment. The method is based on the factor Analysis which is very popular and powerful statistical technique.

• Journal of the Korean Mathematical Society
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• v.47 no.4
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• pp.767-788
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• 2010

In this paper, we propose two limited memory BFGS algorithms with a nonmonotone line search technique for unconstrained optimization problems. The global convergence of the given methods will be established under suitable conditions. Numerical results show that the presented algorithms are more competitive than the normal BFGS method.

• Journal of the Korean Mathematical Society
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• v.47 no.1
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• pp.63-70
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• 2010

In this paper, we develop a nonmonotone spectral memory gradient method for unconstrained optimization, where the spectral stepsize and a class of memory gradient direction are combined efficiently. The global convergence is obtained by using a nonmonotone line search strategy and the numerical tests are also given to show the efficiency of the proposed algorithm.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.7
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• pp.889-897
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• 1999

In this paper, we propose a new method of path planning for autonomous mobile robot in mapped circumstance. To search the optimal path, we adopt the genetic algorithm which is based on the natural mechanics of selection, crossover and mutation. We propose a method for generating the path population, selection and evaluation in genetic algorithm. Simulations show the efficiency for the global path planning, if we adopt the proposed GA method