• Journal of Electrochemical Science and Technology
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• v.8 no.4
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• pp.282-293
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• 2017

A new modified carbon paste electrode (CPE) was constructed based on nickel oxide nanoparticles (NiONPs) and graphene nanosheets (Gr) for simultaneous determination of paracetamol (PCM) and mefenamic acid (MFA) in aqueous media and pharmaceutical dosage forms. NiONPs were synthesized via a simple and inexpensive technique and characterized using X-ray diffraction method. Scanning electron microscopy was used for the characterization of the morphology of modified carbon paste electrode (NiONPs/Gr/CPE). Voltammetric studies suggest that the NiONPs and Gr provide a synergistic augmentation that can increase current responses by improvement of electron transfers of these compounds on the NiONPs/Gr/CPE surface. Using cyclic voltammetry, the NiONPs/Gr/CPE showed good sensitivity and selectivity for the determination of PCM and MFA in individually or mixture standard samples in the linear range of $0.1-30{\mu}g\;mL^{-1}$. The resulted limit of detection and limit of quantification were 20 and $60ng\;mL^{-1}$ for PCM, 24 and $72ng\;mL^{-1}$ for MFA, respectively. The analytical performance of the NiONPs/Gr/CPE was evaluated for the determination of PCM and MFA in pharmaceutical dosage forms with satisfactory results.

• Journal of the Korean Electrochemical Society
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• v.4 no.1
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• pp.26-33
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• 2001

This article involves the application of the fractal geometry to interfacial electrochemistry. Especially, we gave our attention to impedance behaviour of the fractal electrode. First, this article briefly explained the constant phase element (CPE) in electrochemical impedance and the do Levie's transmission line model. Second, we introduced the Nyikos and Pajkossy's theoretical works to approach the CPE phenomena using the fractal geometry. Finally this article presented other various fractal models for analysing the ac response of the rough electrodes.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.622-629
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• 2003

Generally, a silicone rubber and a chloride polyethylene(CPE) have been used for the development of high-performance composite EM(ElectroMagnetic) wave absorber. In this study, the EM wave absorption abilities for natural lacquer which is newly suggested in this study as a binder for composite EM wave absorber were investigated to develop an improved EM wave absorber In addition, MnZn ferrite composite EM wave absorber mixed with the natural lacquer were prepared and their absorption ability was also investigated. MnZn ferrite composite EM wave absorber which employs the natural lacquer as a binder showed an improved EM wave absorption characteristics in comparison with the conventional binder such as a silicone rubber and a chloride polyethylene(CPE). The matching frequency and the absorption ability of EM wave absorber mixed with natural lacquer can be controled the change of the thickness of them.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.417-430
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• 2009

A BNR comprehensive performance evaluation (BNR CPE) system was established employing system-oriented evaluation methodology for biological nutrient removal (BNR) processes based on the CPE techniques developed by U.S. EPA for evaluation of conventional biological processes. The BNR CPE system applied to five domestic BNR plants adopting $A^2/O$ process confirmed that all target plants except the smallest one had not any serious defective performance and process stability was enhanced with increasing plant size. The system also clearly verified relatively poor performances in anoxic reactors without exception mainly due to influent carbon limit rather than functional defect. Consistent good performances were confirmed even during both winter season and wet weather generally known to be difficult to achieve satisfactory removals. Presentation of evaluation results by modified radar chart system simplified and clarified the evaluation and analysis procedures. The BNR CPE system could not only discover readily the causes of present and prospective poor performances but also facilitate the suggestion of their optimization options. Mutual effect and cause-and-effect among operation parameters and unit processes were also found easily using the evaluation system. The system justified that the adverse effect of defective operating parameters could be compensated by other favorable parameters, especially in anaerobic and anoxic reactors as well as during the winter season.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.245.1-245.1
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• 2013

Polydiphenylacetylene (PDPA) derivatives are a class of conjugated polymer that contain intramolecular excimer emission originating the intramolecular stack structure. In contrast with conventional conjugated polymer, the fluorescence property of PDPA significantly depends on the intramolecular stack structure. In this regard, herein, we investigated new fluorescence switching mechanism of conjugated polyelectrolyte (CPE) based on PDPA. The developed CPE showed relatively weak fluorescence emission in water, while the polymer exhibited a great fluorescence amplification behavior by electrostatic complex with proteins. In addition, the CPE is highly sensitive to binding with a little protein despite of turn-on type fluorescence response. We found that the fluorescence switching of the CPE closely relate to a perturbation of the intramolecular stack structure. The new fluorescence switching mechanism of the CPE is very useful for protein assays and discrimination and it also would be provide new sensing approaches as basic sensing mechanism.

• Journal of Electrochemical Science and Technology
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• v.13 no.4
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• pp.479-485
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• 2022

The power of energy storage devices is characterized by capacitance and the internal resistance. The capacitance is measured on an assumption that the charges are stored at the electrode interface and the electric double layer behaves like an ideal capacitor. However, in most cases, the electric double layer is not ideal so a constant phase element (CPE) is used instead of a capacitor to describe the practical observations. Nevertheless, another problem with the use of the CPE is that CPE does not give capacitance directly. Fortunately, a few methods were suggested to evaluate the effective capacitance in the literature. However, those methods may not be suitable for supercapacitors which are modeled as an equivalent circuit of a CPE and resistor connected in series because the time constant of the equivalent circuit is not clearly studied. In this report, in order to study the time constant of the CPE and find its equivalent capacitor, AC and DC methods are utilized in a complementary manner. As a result, the time constants in the AC and DC domains are compared with digital simulation and a proper equation is presented to calculate the effective capacitance of a supercapacitor, which is extended to an electrochemical system where faradaic and ohmic processes are accompanied by imperfect charge accumulation process.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.14 no.7
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• pp.756-761
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• 2003

The microwave absorption properties of silicone, chloride polyethylene(CPE), and natural lacquer which is newly suggested in this study as a binder for composite microwave absorber were investigated to develop a superior microwave absorber. MnZn ferrite composite microwave absorbers mixed with them were prepared and their absorption property was investigated. A MnZn ferrite microwave absorber mixed with natural lacquer showed an excellent microwave absorption property in expanded frequency band.

• Architectural research
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• v.17 no.2
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• pp.75-81
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• 2015

Insulation and condensation performance evaluation (I&CPE) is an important energy analysis. While considerable amount of data are already represented in a Building Information Model (BIM), the lack of interoperability between BIM modeling and I&CPE programs prevents the simulation process from being efficient and accurate. This study proposes a prototype of a BIM-based I&CPE simulation program, in order to enhance the interoperability between BIM modeling and I&CPE programs. This study discusses the information flow process, defines the required information and its level of detail, develops standardized libraries, and finally proposes a prototype that consists of a data extraction module, conversion module, and performance module. The assurance of interoperability between systems might greatly benefit architects and energy professionals.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.107-108
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• 2007

In this paper, the EM wave absorbers were designed and fabricated for collision-avoidance radars using Carbon of a dielectric material and Permalloy of a magnetic material with CPE, because radar system has some problems including false image and system-to-system interference. We fabricated some samples in different composition ratio of Carbon and Permalloy, and defined that optimum composition ratios of Carbon and Permalloy with CPE were Carbon:CPE=20:80 wt% and Permalloy:CPE=70:30 wt%. And absorption abilities at different thicknesses of the EM wave absorbers were simulated using the material properties. The EM wave absorbers were manufactured based on the simulated design. Simulated and measured results agree very well.

• The Journal of the Korea Contents Association
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• v.16 no.6
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• pp.537-549
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• 2016

Interest in spirituality in the workplace is rising as an alternative to overcome the possibility of burnout of social workers. This research has evaluated the results of spirituality education program to social workers in senior welfare centers. CPE(Clinical Pastoral Education) was provided to 25 social workers in 3 different senior welfare centers for 12 to 14 weeks. 4 Focus group interviews with 24 education participants after the end of education were conducted. For the participants of CPE, there were changes in individual levels(habituation of self-reflectivity, the integration of personal spirituality and social worker's spiritualty, expansion of self-awareness and pursuit of altruism), practice behavior(recognition of client's individualism, getting rid of the obsession of proposing a resolution, active listening), and organization levels(intimate fellowship, increase in horizontal relationship in the agencies). Pursuing changes within the organization towards integrating individual and organization spirituality along with social welfare organizations helping the development of social worker's individual spirituality for the simultaneous growth of social workers and the organizations is necessary.