• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.191-194
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• 2002

We analyzed radiation characteristics of dipole antenna in a lossy 9round with conducting object located above ground. Electric field integral equation is used to solve the problem. In this integral equation, GPOF(Generalized Pencil of Function) method is applied to derive the closed form of the electric field due to a current source. Surface current on a conductor is expanded with a well-known vector triangle basis function. The singular integration of a triangle patch is transformed to the non-singular integration by Duffy's method. This transformed non-singular integration is easily calculated by using one-dimensional Gaussian quadrature rule, instead of usual closed form evaluation.

• Korean Journal of Child Studies
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• v.26 no.4
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• pp.189-207
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• 2005

This study examined the effects of picture storybook making activities with computer plays on children's storytelling ability and creativity. Seventy 5-year-old children from two day-care classes participated in this eight-week program. The experimental class used the computer software of 'Stanley's Sticker Stories.' The comparison class used paper and pencil. Data analysis was implemented by ANCOVA and t-test. Significant differences were found between the experimental and comparison groups in story telling ability by story structure, imagination, vocabulary, sentence structure, and creativity showing that picture storybook making activities with the computer was more effective than traditional picture storybook making activities.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1247-1252
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• 2012

In this paper, a potentiometric sensor based on polyaniline conducting polymer for potentiometric determination of Cr (VI) ions is reported. Polyaniline was synthesized electrochemically (cyclic voltammetry method) onto a micro pencil graphite electrode (0.7 mm diameter) in the presence of HCl and diphenylcarbazide (termed as (PGE/PAni/DPC). Some initial experiments were performed in order to find out the optimized conditions for preparation of the introduced Cr (VI) sensor electrode. The plot of E vs. log [Cr (VI)], showed a linear response in the range from $1.0{\times}10^{-6}$ to $1.0{\times}10^{-1}$ M. High repeatability with the detection limit of $8.0{\times}10^{-7}$ M was obtained.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1983.05a
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• pp.18.2-18
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• 1983

Children constitute a large majority of patients with foreign bodies in the nose. Adults with foreign bodies in the nose are usually mentally disturbed, and may be the victims of penetrating injuries or of operation on the nose. Foreign bodies enter the nose through the anterior naris, posterior naris, penetrating wound, $.$$.$$.$$.$ etc. Authors experienced a case of the broken pencil, 3.5cm in length, which entered the nose through the cheek and stayed there for 4 days.

• Journal of Gifted/Talented Education
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• v.7 no.1
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• pp.77-116
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• 1997

The paper-and-pencil multiplce choise test has been widely used to identify gifted and talented student in Korea. Such test have several drawbacks; such~a s not being able to assess creative problem solving abilities and high level thinking abilities which are important characteristics of gifted students. The Korean Educational Development Institute (KEDI) developed a performance assessment which challenged traditional methods of identification. The 5-day summer camp was held to select gifted students for the Korean Minjok Leadership Academy. 211 students were evaluated in the aspects of creative problem solving abilities, high level thinking abilities, task commitments, and cooperativeness with various performance tasks, such as essay tests, conversations, oral examinations, computer simulations, puzzles, experiments, group discussions, debates, research reports, and games. As a result, it was found that there were several limitations of the performance assessment in terms of low reliability, requiring high costs and many professionals, and taking long times and large spaces. Expanding and continuing research should follow in order for a performance assessment to use widely as an identification methods because it assesses 'true' abilities of each individual student. follow in order for a performance assessment to use widely as an identification methods because it assesses 'true' abilities of each individual student.

• Journal of Elementary Mathematics Education in Korea
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• v.13 no.2
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• pp.231-245
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• 2009

Almost every children are naturally non competitive, so they have test anxiety. Because grading in paper-pencil tests is related to competition with their friends. Intense competition should not be a part of the classroom environment. This study intends to reflect current standardized tests(summative evaluations) in an elementary school mathematics(2008) and reconstructed it's problem. Teachers should provide students with rich situational problem-solving opportunities. Therefore we conclude "summative evaluation are consisted of some large problem type which contain some subproblems, or from easy(simple) problem with relation to difficult problem)".

• The Mathematical Education
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• v.53 no.1
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• pp.57-73
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• 2014

This study investigated the connections of mathematical thinking of students at the second, fourth, and sixth grades with regard to multiplication, fraction, and proportion, all of which have multiplicative structures. A paper-and-pencil test and subsequent interviews were conducted. The results showed that mathematical thinking including vertical thinking and relational thinking was commonly involved in multiplication, fraction, and proportion. On one hand, the insufficient understanding of preceding concepts had negative impact on learning subsequent concepts. On the other hand, learning the succeeding concepts helped students solve the problems related to the preceding concepts. By analyzing the connections between the preceding concepts and the succeeding concepts, this study provides instructional implications of teaching multiplication, fraction, and proportion.

• The Mathematical Education
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• v.53 no.2
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• pp.163-184
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• 2014

The purpose of this study was to develop the assessment tools using graphing calculators for the assessment of the mathematical process which was emphasized in 2009 reformed mathematics curriculum. In this paper, we presented three sample calculator-based test items for the assessment of students' mathematical process abilities and scoring rubrics for the paper and pencil assessment and assessment based on observation on each item. In order to improve mathematics teachers' understanding of the assessment tools using graphing calculators and to show the procedures of assessment using technological devices, we also drew up assessment guidelines. We hope the results of the study contribute to the promotion of assessment environment encouraging the use of graphing calculators in assessments.

• Journal of the Korean Applied Science and Technology
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• v.31 no.3
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• pp.472-477
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• 2014

A voltammetric investigation of Au assay was conducted at a low cost, using Nafion and DNA immobilized on a graphite Pencil working electrode (NDP) with a black lead counter and reference. The following optimal parameters were found: 0.4 V amplitude, 500 Hz frequency, -0.7 V initial potential, and 0.015 V increment potential. These optimal conditions were also applied to sand obtained from the river site. The aforementioned technique is simpler and less costly compared to the common voltammetry and spectrophotometric methods.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.209-219
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• 2018

Colloidally stable organic-inorganic (O-I) hybrid nanoparticles could be prepared using an alkoxysilanefunctionalized amphiphilic polymer (AFAP) precursor. O-I hybrid sols could maintain colloidal stability for six months even at 45% solid content and be coated onto glass as well as PET film to form transparent O-I hybrid films. The formation of O-I hybrid nanoparticles dispersed in cured coating films could be confirmed using scanning electron microscopy. The cured coating film showed 3H and 5H pencil hardness on PET and glass, respectively. Nanoindentation measurements also showed that their modulus and hardness was varied with the type of AFAP used in its preparation.