• Journal of applied mathematics & informatics
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• v.31 no.3_4
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• pp.499-511
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• 2013

In this article, Adomian decomposition method (ADM), variation iteration method(VIM) and homotopy analysis method (HAM) for solving integro-differential equation with singular kernel have been investigated. Also,we study the existence and uniqueness of solutions and the convergence of present methods. The accuracy of the proposed method are illustrated with solving some numerical examples.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.75-80
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• 2000

Evaluation method of seismic performance has mainly used elastic spectrum analysis. This method has simplicity of analysis but deficiency of accuracy. And evaluation method of seismic performance using inelastic dynamic analysis reflects accurately inelasticity of material but hardly reflects site effects. This study suggested evaluation scheme of seismic performance for bridge structure using capacity spectrum method applied inelastic static analysis and standard design response spectrum of Korea Standard Specification for Highway Bridge. Two results, capacity spectrum method and inelastic dynamic analysis method, are very similar. As a result, this study appropriately supply both simplicity of analysis and accuracy of result.

• Korean Journal of Microbiology
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• v.23 no.1
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• pp.49-55
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• 1985

The survival of Escherichia coli in river water was comparatively studied by laboratory and in sity study methods. The survival by two methods was evaluated as a function of E. coli strain, indigeneous predator, level of water pollution, and water temperature in different season. The survival rate of E. coli examined by laboratory method was lower than that by in situ method. That was found to be due to the fact that higher number of predator was maintained in labortory study than in in situ study. The survival rates of E. coli in gradually polluted river waters could be differentiated by in situ study, but not by laboratory study. Therefore, an in situ method rather than labortory method was thought to be a choice of study method for the survival of E. coli in river waters.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.117-121
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• 2002

The purpose of this study was to Identification the Risk of construction method to protect and reduce the risk of construction period. For this study we are using the pre and during construction period Inspection list. The inspection list was used by construction company for check a flaw of Construction field. So we rearrange the individual item of inspection list to match the Risk factor. This inspection list usually has the difference of importance because this list is not made by Method which is not focused on Method. Therefore, To find the difference of these importance, We surveyed this matter by doing interview of specialist group. To find the application of field and the possibility of measurement of Risk status, We tested Risk occurring frequency and it's strength by checking the level of Risk. The results of this study were as follows; Each Method Check List made out through the rearrangement of Construction Inspection list which used in construction company. To solve and compensate the matter which happened by changing the each Method Check List to each General Inspection List, we added the each Method Check List by checking the importance of check list of each process. By doing this, The Check List for finding Risk level of Method was created by using the check list of each Method.

• Hwankyungkyoyuk
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• v.24 no.4
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• pp.1-10
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• 2011

The purpose of this study is to investigate effects of environmental education using method of rephrasing lyrics of songs on environmental sensitivity. In order to perform this study, 60 sixth-grade students in an elementary school in Seoul are selected and divided into two groups. Half of the students belong to the experimental group which undergoes environmental education using method of rephrasing lyrics of songs. The others are in the control group which gets traditional environmental education with textbook. A questionnaire was used to survey effects of environmental education using method of rephrasing lyrics of songs. The results of this study are as follows: First, it is found that the environmental education using method of rephrasing lyrics of songs is effective on building up the environmental sensitivity. Second, the environmental education using method of rephrasing lyrics of songs is effective on 4 domains of the environmental sensitivity - positive reception, expectation, disagreeableness and anger for environment and environmental problems. Moreover, the environmental education using method of rephrasing lyrics of songs makes the students in the experimental group have pro-environmental attitudes and behavior. This study revealed that using method of rephrasing lyrics of songs could be effective on the environmental education. Therefore, we have to provide a variety of chances using this method to enhance the environmental sensitivity.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.2
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• pp.105-111
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• 1997

Chlorine dioxide is being used to control THMs formation or taste & odor in water treatment plant. Recently, some operators or academic circles doubted the effectiveness of stabilized chlorine dioxide which is presumed as a liquid form of chlorine dioxide. In this study, we investigated components which consist of stabilized chlorine dioxide in terms of chlorine dioxide and chlorite. Two analytical methods used in this study are UV method and Iodometric method. Iodometric method is recommended by Korean EPA to check the purity of stabilized chlorine dioxide. The samples of stabilized chlorine dioxide from four water treatments were investigated and compared with that produced from chlorine dioxide generator on-site. This study demonstrated that the component of stabilized chlorine dioxide was overwhelmingly chlorite (${ClO_2}^-$) not chlorine dioxide ($ClO_2$) by UV method. It was also proved that Iodometric method (2nd method) recommended by Korean EPA could not differentiate between $ClO_2$ and ${ClO_2}^-$. Iodometric method (2nd method) recommended by Korean EPA should be revised accordingly to measure chlorine dioxide properly.

• Journal of the Korean Wood Science and Technology
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• v.33 no.5 s.133
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• pp.29-37
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• 2005

A previous study verified that the SIRT (simultaneous iterative reconstruction technique) method is more efficient than the back-projection method as a CT algorithm for wood. However, it was expected that the determination of the initial model function of the SIRT method would influence the quality of CT image. Therefore, in this study, we intended to develop a technique that could be used to determine an adequate initial model function. For this purpose, we proposed several techniques, and for each technique we examined the effects of the initial model function on the average errors and the CT image at each iteration. Through this study, it was shown that the average error was decreased and the image quality was improved using the proposed techniques. This tendency was most pronounced when the back-projection method was used to determine the initial model function. From the results of this study, we drew the following conclusions: 1) The initial model function of the SIRT method should be determined with careful attention, and 2) the back-projection method efficiently determines the initial model function of the SIRT method.

• Journal of the Korea Institute of Building Construction
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• v.2 no.4
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• pp.131-135
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• 2002

The purpose of this study was to Identification the Risk of construction method to protect and reduce the risk of construction period. For this study we are using the pre and during construction period Inspection list. The inspection list was used by construction company for check a flaw of Construction field. So we rearrange the individual item of inspection list to match the Risk factor. This inspection list usually has the difference of importance because this list is not made by Method which is not focused on Method. Therefore, To find the difference of these importance, We surveyed this matter by doing interview of specialist group. To find the application of field and the possibility of measurement of Risk status, We tested Risk occurring frequency and it's strength by checking the level of Risk. The results of this study were as follows; Each Method Check List made out through the rearrangement of Construction Inspection list which used in construction company. To solve and compensate the matter which happened by changing the each Method Check List to each General Inspection List, we added the each Method Check List by checking the importance of check list of each process. By doing this, The Check List for finding Risk level of Method was created by using the check list of each Method.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.357-364
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• 1999

The purpose of this study is to analysis the grain distribution and compaction characteristics of structural backfill with reclaimed soil. Five(5) reclaimed soil samples which passed #200 sieve have been used in the test. The study showed that the maximum dry density and the bearing value rate turned out to be becoming smaller when the more the quantity passed #200 sieve, the smaller the soil grain. The maximum dry density value calculated from the compaction md relative density test showed wet method > compaction method > dry method. The correlation coefficient between Rc and Dr based on the grain distribution and the compaction characteristics showed that the maximum dry density value by the wet method is little higher than the compaction method and dry method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.203-206
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• 2005

The purpose of this study is to develop the evaluation method of repair performance for the repair method of reinforced concrete structures deteriorated due to combined deterioration, its results are summarized as the follows. After investigating and analyzing the experimental data of this study and existing research, it is proposed the evaluation method on the repair performance for the repair method of reinforced concrete structures using evaluation method of reinforcing corrosion by combined deterioration accelerated test.