• Education of Primary School Mathematics
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• v.17 no.2
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• pp.127-157
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• 2014

The purpose of the study is to enhance the figure analysis ability for pre-service elementary teacher by using GSP. To do this, we limited to teaching competence divide into ability various problem-solving, extract key elements, predict the difficulty of student and investigated the initial of them, the reality of GSP construction. As results, pre-service elementary teachers made errors, proposed teaching focused on the character using in the problem solving, and found that in one particular difficulties to find the students. The reality of GSP construction activity was possible to explore through the partially constructed a number of various properties, but we found to have difficulty in the connection between concepts. and integrated view of the problem analysis. After visual identification and exploration through the GSP construction, problem-solving ability became a little more variety and changed their direction in order to focus the student's anticipated difficulties. From these results, we could extract some pedagogical implications helping pre-service teachers to reinforce teaching competence by GSP construction.

• The Mathematical Education
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• v.50 no.2
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• pp.233-246
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• 2011

The geometry field in the current high school curriculum deals mainly with analytic geometry and the reference to logic geometry leaves much to be desired. This study investigated the construction on a heptagon by using conic sections as one of measures for achieving harmony between analytic geometry and logic geometry in the high school curriculum with the Geometer's Sketchpad(GSP), which is a specialized software prevalent in mathematics education field and is intended to draw an educational suggestion on it.

• Journal for History of Mathematics
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• v.21 no.2
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• pp.71-80
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• 2008

From the ancient Korea, our ancestor had designed the unique pattern which is Dan-chung, in architectures such as palace and Buddhist temple. In Dan-chung pattern, there are many various kinds, that is geometric pattern, arabesque pattern, plant pattern, flower pattern, animal pattern, Buddhist pattern and living pattern. So, we can see the tessellations in the Dan-chung pattern, moreover we can find the beauty of tessellation in the Korean traditional architectures and crafts. In this paper, I'll show you Korean traditional tessellations via GSP 4.0. which means geomeric program Geometer's SkechPad.

• Journal of Educational Research in Mathematics
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• v.24 no.4
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• pp.515-536
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• 2014

In the present study, we analyze four seventh grade students' recognition of geometric properties and the following justification processes while their adopting different construction approaches in GSP(Geometer's Sketchpad). As the students recognized dependency and level-1 invariants by dragging activities, they determined their own construction approaches. Two students, who preferred robust construction, immediately recognized the path of a draggable point and provided step-1 justification. The other students attempted soft construction followed by their recognition of level-2 invariants and the path, and came to step-2 justification.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1272-1277
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• 2009

Since improved capacity for RC bridges has been required due to deterioration or increase in traffic, the deflection of cracked reinforced concrete slabs need to be reconsidered. Strengthening is known as the better way to improve capacity of bridges than reconstructing. In this paper, Fiber Reinforced Plastic (FRP) was introduced as one of the best strengthening methods for civil structures. The structures strengthened with FRPs can improve the strengthening capacity and serviceability. Therefore, CFRP sheet and Glass Fiber-Steel Composite Plate (GSP) in this research were used for strengthening slabs of RC bridges. Experimental data from the strengthening will be helpful to better understand the effect of the strengthening and effective flexural rigidity.

• Journal of Educational Research in Mathematics
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• v.11 no.1
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• pp.193-206
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• 2001

This study was designed to develop investigation- and exploration- activities on Euclidean geometry with an exploratory type software, Geometer's Sketchpad, and to gain insights into the geometric reasoning abilities of college students working with the software. A package of Euclidean geometric activities with GSP was developed and four college students worked on the several activities with GSP and their geometric reasoning process were analyzed. Results indicated that GSP helped students solve problems in the several ways: to make conjectures and discover theorems by providing precise construction and measurement; to discover their proofs by providing the visual images and its manipulation; and to make students easily apply "what-if"strategies and expand and deepen their activities. Students' geometric reasoning was highly depended on analytic methods and their abilities with synthetic methods were shown very limited.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.7
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• pp.473-479
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• 2012

Water reuse has been highlighted as a representative alternative to solve the lacking water resource. This study carried out a study on the pipe corrosion and water quality change which can occur through the supply of reclaimed water, using a simulated reclaimed water distribution pipeline. Galvanized steel pipe (GSP), cast iron pipe (CIP), stainless steel pipe (STSP) and PVC pipe (PVCP) were used for the pipe materials. Reclaimed water(RW) and tap water(TW) were respectively supplied into simulated reclaimed water distribution pipelines. As a result of performing a loop test to supply reclaimed water to simulated reclaimed water distribution pipelines, the weight reduction of pipe coupons showed the sequence of CIP > GSP > STSP ${\approx}$ PVCP. In addition, reclaimed water showed a high corrosion rate comparing to that of tap water. In case of CIP, the initial corrosion rate showed 3.511 mdd(milligrams per square decimeter per day) for reclaimed water and 2.064 mdd for tap water and the corrosion rate for 90 days showed 0.833 mdd for reclaimed water and 0.294 mdd for tap water. Also in case of GSP, the initial corrosion rate showed 2.703 mdd for reclaimed water and 2.499 mdd for tap water and the corrosion rate for 90 days showed 0.349 mdd for reclaimed water and 0.248 mdd for tap water, which was a tendency similar to that appeared in CIP with a tendency to reduce the corrosion rate. As a result of water quality changes of reclaimed water at pipe materials to carry out the loop test, there was higher conversion ratio of ammonia into nitrate in CIP and GSP with higher corrosion rate than that in STSP and PVCP where no corrosion has occurred. The highest denitrification rate of nitrate could be observed from CIP with the most particles generated from corrosion. In CIP, it could be confirmed that there was MIC (Microbiologically Induced Corrosion) as a result of EDS (Energy Dispersive X-ray spectrometer System) analysis results.

• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.43-51
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• 2008

This study examines shear capacity performance and structural characteristics of reinforced concrete beam using carbon fiber sheet(CFS), g)ass fiber sheet(GFS), glass fiber steel plate(GSP) and carbon fiber bar CB) which are reinforcing materials for reinforced concrete beam in order to produce similar condition to repair and reinforce actual structure and aims to provide data available In designing and constructing reinforced concrete structures under the structural damage. This study obtains the following conclusions. After considering the shear experiment results. it was indicated that the CB reinforced test object was the best in the shear capacity improvement and ductility capacity as it was contained in the concrete and was all operated, Also, GFS reinforced test object indicated the reduced flexural capacity but good shear capacity. GSP reinforced test object had bigger reinforcing strength than other reinforcing test objects. On the other hand, it showed the lowest reinforcement effect as compared section thickness of reinforced material because it showed the bigger relativity a section thickness of reinforced material. If the adherence to the concrete is improved, it will seem to show bigger reinforcement effect.

• Journal of Korea Multimedia Society
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• v.5 no.5
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• pp.590-598
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• 2002

For efficient sequential pattern mining, we need to reduce the cost to generate candidate patterns and searching space for the generated ones. Although Apriori-like methods like GSP[8] are simple, they have some problems such as generating of many candidate patterns and repetitive searching of a large database. PrefixSpan[2], which was proposed as an alternative of GSP, constructs the prefix projected databases which are stepwise partitioned in the mining process. It can reduce the searching space to estimate the support of candidate patterns, but the construction cost of projected databases is still high. To solve these problems, we proposed SuffixSpan(Suffix checked Sequential Pattern mining) as a new sequential pattern mining method. It generates a small size of candidate pattern sets using partition property and suffix property at a low cost and also uses 1-prefix projected databases as the searching space in order to reduce the cost of estimating the support of candidate patterns.

• Journal of Korean Society on Water Environment
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• v.18 no.3
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• pp.303-312
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• 2002

Polly-pigs technique was developed to remove internal rusts and scales from service pipes in the building by using Polly-pigs that were used as various applications in conventional plant pipelines. Results of cleaning experiments on 15mm GSP(Galvanic Steel Pipe) showed that hydraulic cross sectional area was more increased from 3.5% to 15.4% for straight part or elbow parts of several test pieces. Results of optical analysis also showed that rust and scale removed mostly by KDP series(only consisted of Polyurethane) were outside red colored scale ($Fe_2O_3{\cdot}H_2O$), and there was a limitation to the removal of black colored scale($Fe_2O{\cdot}nH_2O$) that was below red colored scale. But it was evaluated that KDPS series coated fine sand with KDP series could remove not only red colored scale but also black colored scale and more increase hydraulic cross sectional areas of 15mm GSP old service pipes from 13.0% to 17.9%. After KDPS series cleaning, hydraulic cross sectional areas of them were recovered from 95.9% to 99.5%. Turning force of Polly-pigs was largely improved by the effect of Helical guide vane(Cleaning v/v) and Rotating wing(Pigs), and the number of pig rotating also more increased sixteen times compared with conventional cleaning system without Helical guide vane and Rotating wing. After KDPC series cleaning of 100mm GSP old service pipes that hydraulic cross sectional areas were 90%, hydraulic cross sectional areas were almost recovered perfectly like new service pipes. Additionally pressure necessary to run Polly-pigs m 100mm GSP was lower and cleaning efficiency also was higher than 15mm GSP cleaning. Therefore it was thought that as the diameter of pipe was more increased, pressure necessary to clean service pipes was more decreased and cleaning efficiency was more increased in Polly-pigs cleaning.