• Design & Manufacturing
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• v.13 no.3
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• pp.6-10
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• 2019

In this study, a study was carried out that could effectively produce a heat dissipation effect on plastic materials. Using carbon nanotube (CNT), aluminum powder and plastic, the material properties were tested in 2 cases of compounding ratio. The test sample mold was designed and constructed prior to the experiment. The experiments include tensile strength, elongation rate, flexural strength, flexural elasticity rate, eye-jaw impact strength, gravity and thermal conductivity. Results from 60% and 70% mixture of aluminium to plastic were tested, and a 10% less combined result was a relatively good property. For research purposes, the heat dissipation effect and light weighting obtained a good measure when the combined amount of Al was 60%.

• Radioisotope journal
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• v.21 no.4
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• pp.55-65
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• 2006

A passive type radon monitor adopting two silicon PIN detector as radiation detector has been developed, manufactured and test-evaluated. A radiation signal processing circuit has been electronically tested and then the radiation detection characteristics of this instrument has been performance-tested by using reference radon concentration and a reference photon radiation field. As a result, in a electronic performance test, radiation signals from each detector were well observed in each signal processing circuit. The radiation detection sensitivity of this instrument after several test-irradiations to a Cs-137 gamma radiation source and a standard radon concentration appeared to be 1.37 cph/$\mu$Svh-1 and 1.66 pCi/L respectively. The developed radon monitor in this paper could be used conveniently in monitoring of radon concentration in buildings which population utilize in Korea.

• The Journal of the Korea Contents Association
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• v.19 no.6
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• pp.524-540
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• 2019

We researched about the relationship among the Purpose of Assessment Certificate System, the preparation result, certificate, and, the performance of the assessment certificate on the purpose of the empirical analysis. For the testing of a research model, we tested 170 samples that our colleges tested by The Assessment Certificate System. As a result of the analysis; there are positive and causal effect relationships among the three variables. This study result will expansion and help to maintain performance growth in the college. In the future, the research about the improvement of management performance are needed.

• Structural Engineering and Mechanics
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• v.70 no.1
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• pp.67-80
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• 2019

Strengthening with near surface mounted carbon fibre reinforced polymers (NSM-CFRP) is a strengthening technique that have been used for several decades to increase the load carrying capacity of reinforced concrete members. In Iraq, many concrete buildings and bridges were subjected to a wide range of damage as a result of the last war and many other events. Accordingly, there is a progressive increase in the strengthening of concrete structures, bridges in particular, by using CFRP strengthening techniques. Near-surface mounted carbon fibre polymer has been recently proved as a powerful strengthening technique in which the CFRP strips are sufficiently protected against external environmental conditions especially the high-temperature rates in Iraq. However, this technique has not been examined yet under repeated loading conditions such as traffic loads on bridge girders. The main objective of this research was to investigate the effectiveness of NSM-CFRP strips in reinforced concrete beams under repeated loads. Different parameters such as the number of strips, groove size, and two types of bonding materials (epoxy resin and cement-based adhesive) were considered. Fifteen NSM-CFRP strengthened beams were tested under concentrated monotonic and repeated loadings. Three beams were non-strengthened as reference specimens while the remaining were strengthened with NSM-CFRP strips and divided into three groups. Each group comprises two beams tested under monotonic loads and used as control for those tested under repeated loads in the same group. The experimental results are discussed in terms of load-deflection behavior up to failure, ductility factor, cumulative energy absorption, number of cycles to failure, and the mode of failure. The test results proved that strengthening with NSM-CFRP strips increased both the flexural strength and stiffness of the tested beams. An increase in load carrying capacity was obtained in a range of (1.47 to 4.49) times that for the non-strengthened specimens. Also, the increase in total area of CFRPs showed a slight increase in flexural capacity of (1.02) times the value of the control strengthened one tested under repeated loading. Increasing the total area of CFRP strips resulted in a reduction in ductility factor reached to (0.71) while the cumulative energy absorption increased by (1.22) times the values of the strengthened reference specimens tested under repeated loading. Moreover, the replacement of epoxy resin with cement-based adhesive as a bonding material exhibited higher ductility than specimen with epoxy resin tested under monotonic and repeated loading.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.54-57
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• 2003

In this paper, we propose an algorithm extracting character regions from scenery images. This algorithm works under a severe constraint: each pixel of a result image must be derived from only information of their neighbor pixels. This constraint is very important for a low cost device like a mobile camera. The proposed algorithm is represented by the local and parallel image processing. It has been tested for 100 scenery images. A result shows that the proposed algorithm can extract character regions at a rate of more than 90％. The result was obtained without learning any template images. the algorithm is very useful.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.280-283
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• 1995

In centrifugal barrel finishing, it is easy to establish the optimum working conditions for different workpieces. As they are adjusted in trial and error practically, production efficiency and quality are some- times low In the present paper, firstly, installation of the barrel finishing machine, finishing purpose and working conditions have been analyzed in order to eliminate the defects of the finished surface. Secondly, on the basis of this result, quantity of the water and selection of the media and the compound, etc. have been investigated. As a result, production efficiency and quality have been improved under the specified optimum working conditions. In addition, durability of the media and the compound has been tested experimentally. As a result, it was found that the expected life of the media is about 85 hrs and that of the compound is about 5 hrs. Besides high quality control has been achieved by newly proposed inspection at regular intervals.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.23 no.3
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• pp.81-87
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• 2015

Load master is authorized to be controlled all of loading stuffs for safety of flight such as passenger, baggage, cargo and e.t.c. There are many things are missed even though the weight and balance is the most important process. This study analyzes how the differences of C.G. by among ten load masters of each careers. This study is tested how load-master takes load-control by the respective result based on differences of each practical experiences, gender and a number of certification. In result, all of load masters set C.G. on the stability region. But the practical experience of load master is relative to set better C.G. for economical effectiveness of weight and balance control work.

• Journal of the korean Society of Automotive Engineers
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• v.12 no.1
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• pp.40-48
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• 1990

Bake hardenability of batch annealed steel sheets is investigated in connection with the amount of tensile deformation and the bake hardening condition. This study associates with the method for producing bake hardening materials by means of batch annealing process and for measuring bake hardenability which is not yet fully established. The experimental result demonstrates the relationship between strain distribution and bake hardening behavior in various bake hardening conditions, which provides an essential information for automobile design and related sheet metal forming in a press shop. The result also shows the bake hardenability of the tested material increases as the baking temperature is increased from 150.deg. C. The result assures the bake hardening materials can guarantee reasonably high strength as well as good uniformity in yield strength for the automobile body by sheet metal forming process.

• Journal of the Korean Applied Science and Technology
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• v.21 no.4
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• pp.320-326
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• 2004

We have extracted the natural pine-needles to use ethanol in solvent, and could obtain the refined oil component from pine-needles extract. We have tested the antimicrobial effect from microbe experiment and analyzed with ICP/OES, GC/MS. we could obtain the next conclusion from the result of this experiment. In the first result of this experiment we could know that in case of increasing concentration of pine-needles, the number of microbe decreased more and more. Also we could know that the refined oil component of pine-needles appeared the sterilization effect of S-aureus and E-coli after 96hrs and 120hrs. So we could know that the refined oil component of appeared effect to microbe. In the second result of this experiment we could know that inorganic materials of Ca, Mg, V, Mn etcs from pine-needles detected to ICP/OES analysis and the aromatic compounds from refined oil component of pine-needles was certificated to GC/MS analysis.

• International Commerce and Information Review
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• v.16 no.2
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• pp.69-88
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• 2014

This study examines the effect of external environments such as technological change and competitive intensity on standardization. It was empirically tested by a Korean sample to verify the validity of the research framework. The empirical result confirms that external environments increase the odds of marketing standardization and technology standardization. The result also indicates that technology change and global standardization are related. The data support that firms facing a high rate of technology change stress marketing and technology standardization. The result also confirms that competitive intensity directly influences marketing standardization.