• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.87-95
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• 1995

A rapid and selective co-extraction systems of copper and zinc-thiocyanate complex into various types of alkylamine for the simultaneous determination of two metal ions by atomic absorption spectrometry and ion chromatograph have been proposed. The quantitative extractions of Cu(II) and Zn(II) at 0.1 M-thiocyanate and 0.1 M-HCI were achieved with Aliquat 336-$CHCl_3$. The detection limits of Cu and Zn were 2 ppb and 0.9 ppb respectively.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.159-164
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• 2004

In electrical impedance tomography (EIT), various image reconstruction algorithms have been used in order to compute the internal resistivity distribution of the unknown object with its electric potential data at the boundary. Mathematically the EIT image reconstruction algorithm is a nonlinear ill-posed inverse problem. This paper presents a simultaneous perturbation method as an image reconstruction algorithm for the solution of the static EIT inverse problem. Computer simulations with the 32 channels synthetic data show that the spatial resolution of reconstructed images by the proposed scheme is improved as compared to that of the mNR algorithm at the expense of increased computational burden.

• Analytical Science and Technology
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• v.6 no.4
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• pp.359-362
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• 1993

To find compromise experimental conditions that will allow a group of elements to be run on flame atomic absorption spectrometer without changing the burner height or gas flow rates, measurements were carried out. The optimum absorbance for simultaneous analysis of ten elements was observed at high flow rate of air-$C_2H_2$ as fuel and at 2mm of burner height. At the condition, 73% of mean relative absorbance were achieved.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.266-271
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• 2001

In this study, the performance of the simultaneous heating & cooling water making system using R134a was investigated by simulation. The most important effect upon heating COP was intermediate pressure depending on input water temperature. With the input water temperature of $10^{\circ}C\;and\;20^{\circ}C$, optimum intermediate pressure were 923 and 1040kPa, respectively. At that optimum intermediate pressure, the maximum heating COP of the system operated between $0^{\circ}C$ evaporating temperature and $70^{\circ}C$ condensing temperature were 4.15 and 3.83. With installation of the subcoolers in high or low pressure section, the system COP was increased by reducing the refrigerant mass flow rate. Under the optimum pressure and $10^{\circ}C$ input water temperature, it was found that heating COP was maximized when the low-subcooler and high-subcooler capacity rate were taken by 14% and 13%, respectively.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.88-92
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• 2001

The simultaneous analytical method for 37 residual pesticides was developed by a gas chromatography with $^{63}$ Ni electron capture detector. Pesticides added in soybean sample were extracted with 70% acetone in water and methylene chloride in oder, and then cleaned up via open-column apparatus packed with florisil and alumina N. The Ultra-2 fused capillary column was used to separate the products. The resolution between the last isomeric peak of cypermethrin (56.398 min) and the first isomeric peak of flucythrinate (56.421 min) was not satisfactory and the last isomeric peak of fenvalerate(58.783 min) and the first isomeric peak of fluvalinate(58.835 min) was overlapped. Except for $\alpha$-BHC, dichlofluanid, captan, and captafol, most recoveries were showed over 70%.

• Journal of applied mathematics & informatics
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• v.34 no.5_6
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• pp.359-367
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• 2016

This paper deals with the Cauchy problem for heat equations with coupling moving reactions of mixed type. After obtaining the infinite Fujita blow-up exponent, we classify optimally the simultaneous and non-simultaneous blow-up for two components of the solutions. Moreover, blow-up rates and set are determined. By using the analogous procedures, one can fill in the gaps for the other two systems, which are studied in the paper 'Australian and New Zealand Industrial and Applied Mathematics Journal' 48(2006)37-56.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.956-961
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• 2004

This paper proposes a study on the spherical lens manufacturing by simultaneous 3 axis for NC lathe. We use friction drive system for moving system in experimental diamond turing machine. The diamond turning machine use manufacturing for high quality lens, mirror and many optics products. Especially, the high tech industry require a lot of lens. For example, optical engineering. medical science, space engineering and material engineering etc. The friction drive system is very simple and quiet, compared to ball screw system. We find a problem at the simultaneous 3 axis and suggest a solution. Also, when we manufactured a micro lens. find a problem and solution.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.2
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• pp.140-146
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• 1993

CoMo, NiMo/ZSM-5 catalysts were prepared at Si/Al ratios of 100, 200 and characterized by TGA, XRD and SEM. Simultaneous hydrocracking of n-heptane and hydrodesulfurization of DBT were studied over these catalysts at the ranges of temparatures between 400$^\circ$C and 500$^\circ$C, pressure of 30 $\times 10^5$ Pa and contact time of 0.02g cat. hr/ml feed in a fixed bed flow reactor. It was shown that the hydrocracking activity of n-heptane increased in the order of NM 100, CM 100, NM 200 and CM 200 catalysts. It was also shown that the Hydrodesulfurization activity of DBT increased in the order of CM 200, NM 200, CM 100 and NM 100 catalysts and these results were thought to be that the increase of acidity of catalysts might increase hydrocracking activity of these catalysts but deactive those simultaneously. In this study it was shown that CM 100 and NM 200 were active catalysts in simultaneous hydrodesulfurization of DBT and hydrocracking of n-heptane reactions.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.11
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• pp.974-979
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• 2009

We studied solution-processed single-layered phosphorescent organic light-emitting diodes (PHOLEDs), doped with ionic salt and treated with simultaneous electrical and thermal annealing. Because the simultaneous annealing causes the accumulation of salt ions at the electrode surfaces, the energy levels of the organic molecules are bent by the electric fields due to the adsorbed ions, i.e., the simultaneous annealing can induce the proper formation of an ionic p-i-n structure. As a result, an ionic p-i-n PHOLED with a peak luminescence of over ${\sim}35,000\;cd/m^2$ and efficiency of 27 cd/A was achieved through increased and balanced carrier-injections.

• Journal of Korean Neurosurgical Society
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• v.58 no.4
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• pp.397-400
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• 2015

The simultaneous occurrence of an intracranial and a spinal subdural hematoma (SDH) is rare. We describe a case of cranial SDH with a simultaneous spinal SDH. An 82-year-old woman visited the emergency room because of drowsiness and not being able to walk 6 weeks after falling down. A neurological examination showed a drowsy mentality. Brain computed tomography showed bilateral chronic SDH with an acute component. The patient underwent an emergency burr-hole trephination and hematoma removal. She exhibited good recovery after the operation. On the fourth postoperative day, she complained of low-back pain radiating to both lower limbs, and subjective weakness of the lower limbs. Spine magnetic resonance imaging revealed a thoracolumbosacral SDH. A follow-up spinal magnetic resonance imaging study that was performed 16 days later showed a significant decrease in the size of the spinal SDH. We discuss the pathogenesis of this simultaneous occurrence of spinal and cranial SDH.