• Journal of Fashion Business
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• v.7 no.1
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• pp.38-54
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• 2003

This study looked into the present status of e-mail marketing, which is conducted in local Internet fashion shopping malls and is being used as a one-to-one marketing method in the e-CRM concept so as to establish an effective e-mail marketing policy by grasping problems based on the current status and by presenting solutions to the problems. This study analyzed the e-mail letters received during a certain period of time by 30 professional Internet fashion shopping malls of with famous goods, brands and non-brands. Four individuals subscribed to shopping mall through the procedure for membership applying for e-mail services. The analysis showed that there were no shopping malls that were doing a differentiated e-mail marketing among Internet shopping malls. As for time factor, they were sending e-mail letters irregularly regardless of a certain cycle. And as for visual factor, they didnt have any standard for the content of the mail. As for content factor, the contents of their mail were not differentiated and all the same. The comparison of fashion malls showed that the brand shopping malls were the most active in e-mail marketing. On the basis of the problems, the direction for the effective e-mail marketing of Internet shopping malls are presented as follows: First, individualized contents fitting for customers should be developed, and differentiated mailing services should be provided thereby. Second, each shopping mall should make periodic tests of mailing to find out the optimal time and day to provide e-mail services to the customers at the designated time. Third, e-mail should be differentiated fitting for the website according to a certain on a certain standard for visual effects and the identity of shopping mall should be established. Firth, in the contents of e-mail, the image and message elements should be properly harmonized and creative policies should be made with interactive or recreational elements. Fifth, a homepage policy which can satisfy customers demand for information when the e-mail is clicked on..

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.197-203
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• 2001

An ubiquitous bacterium, Pseudomonar cepacia KH410 was isolated from fresh water plant root and identified. Adsorption of heavy metals of lead, cadmium and copper by this strain was investigated. Optimal conditions foradsorption was 1.0 dry g-biomass, at pH 4.0 and temperature of $40^{\circ}C$. Adsorption equilibrium reached max-imum after 120 min in 1000 mg/l metal solutions. The adsorption capacity (K) of lead was 5.6 times higher thancadmium and 4.0 times higher than that of copper. Adsorption of lead was applicable for Langmuir modelwhereas Freundlich model for cadmium and copper, respectively. Adsorption strength (1/n) of heavy metal ionswere in the order of lead>copper>cadmium. Uptake capacity of lead, cadmium and copper by dried cell was83.2,42.0,65.2 mg/g-biomass, respectively. Effective desorption was induced 0.1 M HCI for lead and 0.1 $HNO_3$ for cadmium and copper. Pretreatment to increase ion strength was the most effective with 0.1 M KOH.Uptake by immobilized cell was 77.8,58.5,71.2 mg/g-biomass for lead, cadmium and copper, respectively. Theimmobilized cell was more effective than ion exchange resin on removal of heavy metals in solution containinglight metals.

• Journal of KIISE:Software and Applications
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• v.28 no.9
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• pp.669-680
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• 2001

Genetic Algorithms are optimization algorithm that mimics biological evolution to solve optimization problems. Genetic algorithms provide an alternative to traditional optimization techniques by using directed random searches to locate optimal solutions in complex fitness landscapes. Hybrid genetic algorithm that is combined with local search called learning can sustain the balance between exploration and exploitation. The genetic traits that each individual in the population learns through evolution are transferred back to the next generation, and when this learning is combined with genetic algorithm we can expect the improvement of the search speed. This paper proposes a genetic algorithm based Cellular Learning with accelerated learning capability for function optimization. Proposed Cellular Learning strategy is based on periodic and convergent behaviors in cellular automata, and on the theory of transmitting to offspring the knowledge and experience that organisms acquire in their lifetime. We compared the search efficiency of Cellular Learning strategy with those of Lamarckian and Baldwin Effect in hybrid genetic algorithm. We showed that the local improvement by cellular learning could enhance the global performance higher by evaluating their performance through the experiment of various test bed functions and also showed that proposed learning strategy could find out the better global optima than conventional method.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.374-380
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• 2006

In this study, glucose, sucrose, and dextrin were found to be better carbon sources for the production of pullulan by Aureobasidium pullulans HP-2001. Maximal production of pullulan with 200 g/l sucrose as a carbon source was 54.2 g/l. The highest yield of pullulan from sucrose was 0.40, when the sugar concentration was 100 g/1. Optimal conditions for the continuous production of pullulan by A. pullulans HP-2001 in a 7-1 bioreactor were determined by studying the effects of composition of feed solution, dilution rate, and concentration of sucrose in the feed solution. Pullulan concentration and productivity with 100 g/l glucose and 2.5 g/l yeast extract were 38.1 g/l and 0.53 g/l h for 72 h, respectively, in a batch culture of A. pullulans HP-2001. When the substituted medium contained 100 g/l sucrose, 2.5 g/l yeast extract, and mineral salts, which is the same composition as the medium for the production of pullulan, the pullulan concentration and productivity were 74.9 g/l and 0.55 g/l h for 120 h, respectively. The production of pullulan at the steady state increased with a dilution rate up to 0.015/h, and its concentration was 78.4 g/l with a weight average molecular weight ($M_w$) of $4.0{\times}10^5$. Unlike a batch culture, however, the decline of the $M_w$ and the number average molecular weight ($M_n$) of pullulan was not found in the continuous culture of A. pullulans HP-2001. When the concentration of sucrose in the feed solution was 200 g/l, 113.5 g/l of pullulan was obtained at the steady state. The steady state was maintained longer in the continuous culture fed with the feed solution containing 200 g/l sucrose than when fed with the feed solutions containing either 100 or 150 g/l sucrose.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.1-14
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• 2017

For the removal of cesium (Cs) from high radioactive/high salt-laden liquid waste, this study synthesized a highly efficient composite adsorbent (potassium cobalt ferrocyanide (PCFC)-loaded chabazite (CHA)) and evaluated its applicability. The composite adsorbent used CHA, which could accommodate Cs as well as other molecules, as a supporting material and was synthesized by immobilizing the PCFC in the pores of CHA through stepwise impregnation/precipitation with $CoCl_2$ and $K_4Fe(CN)_6$ solutions. When CHA, with average particle size of more than $10{\mu}m$, is used in synthesizing the composite adsorbent, the PCFC particles were immobilized in a stable form. Also, the physical stability of the composite adsorbent was improved by optimizing the washing methodology to increase the purity of the composite adsorbent during the synthesis. The composite adsorbent obtained from the optimal synthesis showed a high adsorption rate of Cs in both fresh water (salt-free condition) and seawater (high-salt condition), and had a relatively high value of distribution coefficient (larger than $10^4mL{\cdot}g^{-1}$) regardless of the salt concentration. Therefore, the composite adsorbent synthesized in this study is an optimized material considering both the high selectivity of PCFC on Cs and the physical stability of CHA. It is proved that this composite adsorbent can remove rapidly Cs contained in high radioactive/high salt-laden liquid waste with high efficiency.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.434-439
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• 1993

To investigate the effects of neutral salts on the foaming properties of sodium caseinate, turbidity, surface tension, absolute viscosity, foaming ability and foam stability of the caseinate solutions(5%, w/v) with added NaF, $Na_2SO_4$, NaCl, $NaNO_3$, and NaSCN at concentrations of 0.1, 0.5, 1.0, 1.5 and 2.0 M were examined. NaCl and $NaNO_3$ improved the foaming ability compared to sodium caseinate without salt, and also $Na_2SO_4$ and NaF did the foaming ability at the concentrations of 0.1M and 0.5M, while NaSCN did not improve the foaming ability. For foaming ability optimal concentrations of the salts were 0.5, 1.5, and 1.0 M in $Na_2SO_4$, NaCl, and NaSCN, respectively. Additions of $Na_2SO_4$, NaF and $NaNO_3$ at 0.5 M concentrations improved the foam stability of sodium caseinate by 825%, 615%, and 53% compared to control, while those of NaSCN reduced foam stability.

• Journal of Biomedical Engineering Research
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• v.19 no.6
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• pp.595-602
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• 1998

Among the apex locators, the frequency dependent type is more accurate and convenient to use than others, But the accuracy of the apex locator is still influenced by the presence of various electrolytes used in root canal treatments. In this study, we have developed a frequency dependent electronic apex locator minimizing the influence of the electrolytes on the measurement of root canal lengths. It was also confirmed that two frequencies of 500Hz and 100kHz are optimal for the measuring impedance compare with commercial product used(400Hz and 8kHz)a and there were no differences in accuracy among the three different types of the waveforms; sinusoidal, triangular, and rectangular waves(p>0.05). Impedance ratio of the two different frequencies represents the position of the file in root canal, and the voltage difference of two signals represents the status of the fluid in the root canal. As a result of compensation using the voltage differences, the errors were decreased on the average from +0.54mm to +0.18mm in $H_2O_2$ solution (p<0.01), and from -0.33mm to -0.01mm in NaOCl solution(p<0.01). The accuracies based on ${\pm}$0.5mm, in $H_2O_2$ and NaOCl solutions were improved with the automatic compensation from 71.1% and 91.1% to 82.2% and 100% respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6599-6603
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• 2014

Strengthening the competitiveness of Korean Industrial Technology with cooperation from EU enterprises is very important. With regard to the technological cooperation Framework Program (FP) from the EU during the period, 2007 to 2013, the most active participants involved were Germany, England and France. Additional participants were Russia, China, India, and Brazil. Korean participation as a non-EU Member State in this program was low. The aim of this study was to determine effective activation strategies for FP participation by Korean enterprises and institutions. Chapter 2 reports the theoretical background. Chapter 3 presents the methodology of the study. Chapter 4 describes the $8^{th}$ FP of the EU in detail. Chapter 5 attempts to find a solution for the optimal participation of Korean firms and institutions in the 8th FP of the EU. Through this paper, a solution for $8^{th}$ FP can be found: many Korean enterprises are unaware of the FP. Therefore, it is of the utmost importance to provide information about the characteristics and processes regarding the EU $8^{th}$ FP.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.706-713
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• 2010

The research seeks to find the optimal conditions for sonodegradation of naphthalene and phenol as exemplary organic pollutants to be subjected to ultrasound in varying frequencies (28 kHz, 580 kHz, and 1,000 kHz) and in the presence of different kinds of additive (T$TiO_2$, $H_2O_2$, $FeSO_4$, Zeolite, and Cu). In cases of both naphthalene and phenol, 580 kHz of ultrasound has proven to be the most effective among others at sonodegradation. Based on the observation that OH radicals are also produced in maximum under exposure of 580 kHz of ultrasound, we concluded that this frequency of ultrasound creates hospitable condition for the combined process of degradation by pyrolysis and oxidization. $FeSO_4's$ degradation rate and k1 value have increased by approximately 1.8 times compared with the results of the solutions without any additives. This seems to be the result of ultrasound reaction which, accompanied by Fenton's reaction, increased the oxidative degradation and the production of OH radicals. However, application of ultrasound and Fenton's reaction is limited to the batch type conditions, as its use in continuous system can cause loss of iron or decay of the cistern, thereby creating additional pollutants. When the additive is replaced with $TiO_2$, on the contrary, the rate of sonodegradation has increased up to 20% compared to when there was no additive. We therefore conclude that $TiO_2$ could prove to be an effective additive for ultrasound degradation in continuous treatment system.

• Environmental Engineering Research
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• v.25 no.1
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• pp.88-95
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• 2020

An investigation of rare metals recovery from LiNi_xCo_yMn_zO₂ cathode material of the end-of-life lithium-ion batteries is presented. To determine the influence of reductant on the leach process, the cathode material (containing Li 7.6%, Co 20.4%, Mn 19.4%, and Ni 19.3%) was leached in H₂SO₄ solutions either with or without H₂O₂. The optimal process parameters with respect to acid concentration, addition dosage of H₂O₂, temperature, and the leaching time were found to be 2.0 M H₂SO₄, 4 vol.% H₂O₂, 70℃, and 150 min, respectively. The yield of metal values in the leach liquor was > 99%. The leach liquor was subsequently treated by precipitation techniques to recover nickel as Ni(C₄H₇N₂O₂)₂ and lithium as Li₂CO₃ with stoichiometric ratios of 2:1 and 1.2:1 of dimethylglyoxime:Ni and Na₂CO₃:Li, respectively. Cobalt was recovered by solvent extraction following a 3-stage process using Na-Cyanex 272 at pH_eq ~5.0 with an organic-to-aqueous phase ratio (O/A) of 2/3. The loaded organic phase was stripped with 2.0 M H₂SO₄ at an O/A ratio of 8/1 to yield a solution of 114 g/L CoSO₄; finally recovered CoSO₄.xH₂O by crystallization. The process economics were analyzed and found to be viable with a margin of $476 per ton of the cathode material.