• Advances in nano research
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• v.1 no.4
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• pp.203-210
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• 2013

So far, all reviews and control approaches of spin relaxation have been done on lateral single electron quantum dots. In such structures, many efforts have been done, in order to eliminate spin-lattice relaxation, to obtain equal Rashba and linear Dresselhaus parameters. But, ratio of these parameters can be adjustable up to 0.7 in a material like GaAs under high-electric field magnitudes. In this article we have proposed a single electron QD structure, where confinements in all of three directions are considered to be almost identical. In this case the effect of cubic Dresselhaus interaction will have a significant amount, which undermines the linear effect of Dresselhaus while it was destructive in lateral QDs. Then it enhances the ratio of the Rashba and Dresselhaus parameters in the proposed structure as much as required and decreases the spin states up and down mixing and the deviation angle from the net spin-down As a result to the least possible value.

• Proceedings of the Korean Society for Quality Management Conference
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• 2004.04a
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• pp.413-418
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• 2004

The bounded adjustment is known to be more efficient than repeated adjustment when the cost is incurred for engineering process control. The procedure of the bounded adjustment is to adjust the process when the one-step predicted deviation exceeds the adjustment limit by the amount of the prediction. In this paper, two run rules are proposed and studied in order to improve the efficiency of the traditional bounded adjustment procedure. The efficiency is studied in terms of the standardized cost through Monte Carlo simulation when the procedure is operated with and without the run rules. The adjustment procedure operated with run rules turns out to be more robust for changes in the process and cost parameters. The Markov chain approach for calculating the properties of the run rules is also studied.

• Design & Manufacturing
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• v.17 no.1
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• pp.64-69
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• 2023

This paper explores the impact of gate shape changes on the size and density of foamed cells in microcellular foam injection molding. Five different gate shapes were examined while varying the amount of nitrogen gas(N2) injected for foaming. Analysis of the results showed that while average values did not change significantly, deviation values decreased by approximately 65% for cell size and 56% for density when 3.5wt% of nitrogen gas was injected in the film gate. Further analysis was conducted to verify this phenomenon, revealing that the contact area between the gate and product had the greatest impact. Our findings indicate that to ensure uniform generation of foamed cells in microcellular foaming product design, a gate with a wide contact area should be secured.

• Journal of Family Resource Management and Policy Review
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• v.6 no.1
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• pp.149-165
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• 2002

This study is to understand consumer's information search activity and satisfaction. When they buy the elderly related goods through internet market and to get some ideas for silver industry on internet shopping. The 382 subjects by online banner formatted Questionnaires were analyzed by frequency, percentage, standard deviation, Person's relation and regression analysis by SPSS PC program. The major findings are summarized as follows. (1) The most respondents were young and well-educated. In terms of psychological variables, the degree of the consumer's perception for internet usefulness and using capability were relatively high. (2) Information search amount of the group who have experienced purchasing elderly related goods through internet shopping and had low perception of internet risk is higher than other group. (3) The variables influenced mostly on consumer satisfaction were the age, the sex, the purchasing experience from Internet shopping, the Internet using capacity and the perception of internee usefulness as well as of the perception of internet risk.

• Journal of Korean Society for Quality Management
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• v.32 no.1
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• pp.144-154
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• 2004

The bounded adjustment is known to be more efficient than repeated adjustment when the cost is incurred for engineering process control. The procedure of the bounded adjustment is to adjust the process when the one-step predicted deviation exceeds the adjustment limit by the amount of the prediction. In this paper, two run rules are proposed and studied In order to improve the efficiency of the traditional bounded adjustment procedure. The efficiency is studied in terms of the standardized cost through Monte Carlo simulation when the procedure is operated with and without the run rules. The adjustment procedure operated with run rules turns out to be more robust for changes in the process and cost parameters.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.318-331
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• 2000

Electrical and tribological behaviours of a copper-graphite brush in a slipring-brush assembly were investigated to evaluate the characteristics of electric signal transmission between a slipring and a brush. Five brush materials containing different amounts of copper and graphite were studied. The result showed that a copper-graphite brush at a particular graphite content exhibited the most stable frictional and electrical behaviour suggesting an optimum amount of a solid lubricant in a metal-graphite brush system. Microscopic observation and the surface analysis showed good agreements with this phenomena. In addition, the deviation of the friction coefficient and electric signal distortion has a close relationship with a microscopic mechanical vibration and the change of a real contact area.

• Journal of the Korea Society for Simulation
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• v.13 no.3
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• pp.1-10
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• 2004

The cell loss probability required in the ATM network is in the range of 10$^{-9}$ ∼10$^{-12}$ . If Monte Carlo simulation is used to analyze the performance of the ATM node, an enormous amount of computer time is required. To obtain large speed-up factors, importance sampling may be used. Since the Markov-modulated processes have been used to model various high-speed network traffic sources, we consider discrete time single server queueing systems with Markov-modulated arrival processes which can be used to model an ATM node. We apply importance sampling based on the Large Deviation Theory for the performance evaluation of, MMBP/D/1/K, ∑MMBP/D/1/K, and two stage tandem queueing networks with Markov-modulated arrival processes and deterministic service times. The simulation results show that the buffer overflow probabilities obtained by the importance sampling are very close to those obtained by the Monte Carlo simulation and the computer time can be reduced drastically.

• Proceedings of the KSPS conference
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• 2007.05a
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• pp.138-142
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• 2007

It was the purpose of this study to obtain nasalance values for Chinese and Korean based on Vowels. The NasalView was used to measure the amount of nasal acoustic energy in the speech of 96 normal adults from China and Korea. Means and standard deviations for the nasalance and deviation scores are presented for each of three different vowels. The Chinese speakers were found to have significantly higher nasalance scores on vowel /a/ and /u/.

• Bulletin of the Korean Chemical Society
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• v.23 no.5
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• pp.693-698
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• 2002

A method has been described for the determination of Cu(Ⅱ), Pb(Ⅱ), Ni(Ⅱ), Cd(Ⅱ), Mn(Ⅱ) and Fe(Ⅲ) by flame atomic absorption spectrometry (FAAS) after preconcentration on Amberlite XAD-16 resin, using hexamethyleneammonium-hexamethylenedithiocarbamate (HMA-HMDTC) as a chelating agent, and NH3/NH4Cl buffer solution (pH 9). Influences of various analytical parameters such as pH, concentration of nitric acid, amount of analytes, diverse ions and sample volume were investigated. The relative standard deviation (RSD) and the detection limit (LOD) were found in the range of 0.8-2.9% and 0.006-0.277 ㎍/mL,respectively. Recoveries obtained by the column method were quantitative ( >95%) at optimum conditions.The method was applied to the determination of some metal ions in seawater and wastewater samples. A high preconcentration factor (about 150 for seawater and 75 for wastewater samples) and simplicity are the main advantages of this suggested method.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.249-252
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• 1997

Mini-mill process which is one of the new steel making process to be able to produce the hot rolled strip by thin slab caster, was completed in the kwangyang steel work. The new process was constructed liquid core deduction, tandem reduction unit, induction heater, coil box and finishing mill to be varied width. Therefore, in oder to make sure of target strip width, analysis of actual plant data was done to fine out amount of width deviation. Finally, the predication system of width in the mini-mill process was developed to included temperature caculation model.