• Journal of the Korean Ceramic Society
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• v.53 no.3
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• pp.325-331
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• 2016

Anatase particles of titanium dioxide were prepared from $TiCl_4$ aqueous solution by using an electro-dialysis [ED] process. For the preparation of an aqueous solution of $TiCl_4$ precipitates, $TiCl_4$ liquid frozen in ice was transferred to a neck flask and then hydrolyzed using deionized [DI] $H_2O$. During the hydrolysis of the $TiCl_4$ solution at $0^{\circ}C$, a slurry solution of $TiOCl_2$ was obtained and the color changed from red to orange. The ED process was applied for the removal of chlorine content in the slurry solution. Two kinds of hydrolyzed slurry solution with lower [$Ti^{4+}$] and higher [$Ti^{4+}$] were sampled and the ED process was applied for the samples according to the removal time of [$Cl^-$]. With de-chlorination, the solution status changed from sol to gel and the color quickly changed to blue. Finally, white crystalline powders were formed and the phase was confirmed by XRD to be anatase crystallites. The morphology of the hydrous titania particles in the solution was observed by FE-SEM. The hydrous titania particles were nano-crystalline, and easily coagulated with drying.

• Journal of the Korea Society for Simulation
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• v.25 no.2
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• pp.51-61
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• 2016

With high interest in the patient satisfaction of emergency medical services, there is a lot of effort into improving the process of Emergency Department(ED) utilizing the technology of Internet of Things(IoT). In this study, the core technologies of smart ED are examined and a decision support algorithm for medicine tasks is proposed. The proposed algorithm minimizes the decision risks such as task selection accountability, patient complaints, care delays and longer stay time. It can reduce the nurses burnout and improve the patient care with kindness and consideration. Ultimately, patient satisfaction, job satisfaction and professional identity of nurses can be increased. The comparative study was carried out by simulation in terms of the average length of patient stay in a simplified hypothetical ED system. In all the cases, the proposed algorithm was shown to perform substantially better than the other rule.

• Journal of Advanced Navigation Technology
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• v.12 no.6
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• pp.666-672
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• 2008

This paper explains late comer and error recovery process for home network environment with session management. This system consists of an ED, ES, and ER. ED is an agent that detects an error by hooking techniques for multimedia distance education based on home network environment with session management. ES is an agent that is an error sharing system for multimedia distance education based on home network environment with session management. ER is a system that is suitable for recovering software error for multimedia distance education based on home network environment with session management. This paper explains a performance analysis of an error recovery system running on distributed multimedia environment using the rule-based DEVS modeling and simulation techniques. The proposed method is more efficient than the other method in comparison with error ration and processing time.

• Journal of the Semiconductor & Display Technology
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• v.17 no.2
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• pp.61-66
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• 2018

The objective of this research study is to investigate the optimal process parameters of electrical discharge machining (EDM) on SCM440 steel with copper as a tool electrode. The effect of various process parameters on machining performance is investigated in this study. Modern ED machinery is capable of machining geometrically complex or hard material components, that are precise and difficult-to-machine such as heat treated tool steels, composites, super alloys, ceramics, etc. This paper reports the results of an experimental investigation by Taguchi method carried out to study the effects of machining parameters on material surface roughness in electric discharge machining of SCM440 steel. To predict the optimal condition, the experiments are conducted by using Taguchi's L27 orthogonal array. The work material was ED machined with copper electrodes by varying the pulsed current, pulse on-time, voltage, servo speed and spark speed. Investigations indicate that the surface roughness is strongly depend on pulsed current.

• Journal of Electrical Engineering and Technology
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• v.8 no.1
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• pp.80-89
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• 2013

This paper presents an efficient approach for solving economic dispatch (ED) problems with nonconvex cost functions using a 'Mean-Variance Optimization (MVO)' algorithm with Kuhn-Tucker condition and swap process. The aim of the ED problem, one of the most important activities in power system operation and planning, is to determine the optimal combination of power outputs of all generating units so as to meet the required load demand at minimum operating cost while satisfying system equality and inequality constraints. This paper applies Kuhn-Tucker condition and swap process to a MVO algorithm to improve a global minimum searching capability. The proposed MVO is applied to three different nonconvex ED problems with valve-point effects, prohibited operating zones, transmission network losses, and multi-fuels with valve-point effects. Additionally, it is applied to the large-scale power system of Korea. The results are compared with those of the state-of-the-art methods as well.

• Journal of The Korean Society of Clinical Toxicology
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• v.18 no.1
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• pp.11-17
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• 2020

Purpose: This study examines errors in death certificates (DCs) issued to cases of poisoning. Methods: DCs issued in poisoning cases were retrospectively reviewed. Errors in the DC were classified as major and minor errors, and were evaluated in accordance with their impact on the process of selecting the cause of death (COD). Results: A total of 79 DCs were evaluated; 43 (54.4%) DCs were issued in the emergency department (ED), and 36 (45.6%) DCs were issued outside the ED. The average major and minor errors per DC were determined to be 0.4 and 3.3, respectively. Moreover, an average of 3.0 errors were discovered in DCs issued at the ED, and 4.4 errors in DCs issued outside the ED. The most common major errors were incorrect manner of death (11.4%, 9/79), followed by unacceptable COD (7.6%, 6/79), and the mode of dying as an underlying COD (5.1%, 4/79). The common minor errors most frequently encountered were incorrect time interval (86.1%, 68/79), followed by incorrect other significant conditions (73.4%, 58/79), and no record for date of onset (62.0%, 49/79). Conclusion: Our results indicate that the total numbers of major errors, minor errors and cases of misjudged cause of death were greater in DCs issued outside the ED than in DCs issued at the ED. The most frequently quoted major error of DCs related to poisoning was determined to be the incorrect manner of death.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.8A
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• pp.760-767
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• 2010

For complex channel blind equalization, this study presents the performance and characteristics of two complex blind information theoretic learning algorithms (ITL) which are based on minimization of Euclidian distance (ED) between probability density functions compared to constant modulus algorithm which is based on mean squared error (MSE) criterion. The complex-valued ED algorithm employing constant modulus error and the complex-valued ED algorithm using a self-generated symbol set are analyzed to have the fact that the cost function of the latter forces the output signal to have correct symbol values and compensate amplitude and phase distortion simultaneously without any phase compensation process. Simulation results through MSE convergence and constellation comparison for severely distorted complex channels show significantly enhanced performance of symbol-point concentration with no phase rotation.

• Korean Membrane Journal
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• v.1 no.1
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• pp.8-24
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• 1999

free volume in polymers is defined as the difference of the specific volume and the volume which is not available for the particular molecular motion which is responsible or the process that is considered . Relations between free volume and viscosity free volume and diffusion coefficient are pre-sented both in the case of simple low molecular weight liquids and in the case of polymers. Molecular models and free volume models are reminded starting from the equilibrium state equation of Simha and Somcynski. The non equilibrium situations of specific volume of glass polymers below Tg are shown introducing different relaxation volume equations which involve different material's parameters and con-cept of the fictitious temperature. The diffusivity equations of Vrentas and Duda are introduced both for the glassy and rubbery states. The possibility of introducing time relaxation functions is also suggested. The importance of finding experimental evidences of the free volume is stressed. highlights of the free volume measurement methods are given in particular as to dilatometry photocromy fluorescence electron spin resonance small angle X-ray scattering positron annihilation spectroscopy.

• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1099-1109
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• 2018

For practical consideration, economic dispatch (ED) problems in power system have non-smooth cost functions with equality and inequality constraints that makes the problems complex constrained nonlinear optimization problems. This paper proposes a new constraint handling method for equality and inequality constraints which is employed to solve ED problems, where the incremental rate is employed to enhance the modification process. In order to prove the applicability of the proposed method, the study cases are tested based on the classical particle swarm optimization (PSO) and differential evolution (DE) algorithm. The proposed method is evaluated for ED problems using six different test systems: 6-, 15-, 20-, 38-, 110- and 140-generators system. Simulation results show that it can always find the satisfactory solutions while satisfying the constraints.

• Textile Coloration and Finishing
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• v.33 no.3
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• pp.97-104
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• 2021

In this study, the dyeability of m-aramid fabric with various cationic dyes using two bath two step dyeing method were investigated. The exhaustion properties of Doracryl series recommend for aramid(Doracryl^® Red GL 100%(DR), Doracryl^® Blue GL 300%(DB), Doracryl^® Yellow XGRL 200%(DY)) and commercial cationic Synocryl series(Synocryl^® Red GRL ED(SR), Synocryl^® Blue GSL ED(SB), Synocryl^® Yellow 3RL ED(SY)) for acrylic were measured by using Dye-O-meter. In the presence of carrier, the exhaustions of Doracryl series were higher to those of Synocryl series and the opposite phenomenon was observed in the absence of carrier. And the severe migrations of cationic dyes to acetate, nylon and wool fabrics were observed without carrier.