• Proceedings of the Korea Society of Mathematical Education Conference
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• 2006.05a
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• pp.1-16
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• 2006

The purpose of this study is to investigate how fifth and sixth graders recognize average and to find out suggestions for teaching/learning methods of average by examining which difference there is depending on the way of the word problem presentation. To solve these study questions, With the way of the word problem presentation set up as experimental treatment experiment was conducted to analyze these. In conclusion, since students who did not learn the regular course of average values had various informal concepts already, it is needed to consider handling more various concepts of average in order to enable students to expand flexible thoughts. And informal concepts of average students showed were the same or similar to types of formalized concepts and had logicality and propriety in their own way. Compared with fifth graders, sixth graders showed a wide difference in informal concepts of average depending on the way of the word problem presentation.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.311-315
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• 2000

Recombinant interleukin-2 (IL-2) has been demonstated as an antineoplastic agent in mice and human, and the route of administration is important to IL-2-induced therapeutic responses. Therefore, the current experiment was undertaken to clarify the effect of IL-2 administration route on antitumor response against subcutaneous Meth-A tumor in mice. At the beginning of each experiment, normal BALB/c mice were injected subcutaneously with $5{\times}10^6$ Meth-A tumor cells. Beginning on day 7, experimental groups were treated with a 5-day course of IL-2 (intraperitoneal or subcutaneous injection of 30, 000 IU every 12 hours for 5 days). The result of this experiment revealed that Meth-A tumor grew progressively in control mice. Intraperitoneal IL-2 treatment decreased significantly tumor growth and prolonged survival, compared with control mice. Subcutaneous IL-2 treatment decreased significantly tumor growth until day 11 and tumor cells, grew progressively thereafter, but mice in this group survived longer than control mice.

• Clinical and Experimental Pediatrics
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• v.55 no.8
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• pp.259-264
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• 2012

Wheezing is one of the most frequent complaints that lead to the use of medical resources in younger children. Generally, wheezing is caused by bronchiolitis and resolves spontaneously without recurrence, but sometimes, wheezing can progress into asthma. Early data on the natural history of childhood wheezing was mostly obtained from retrospective reviews of medical records or from questionnaires, which made it difficult to exclude biases. Now that many cohort studies are available, reviewing the results of birth cohort studies makes it possible to understand the natural course of early childhood wheezing and the risk factors for asthma. In this study, we have reviewed the various phenotypes of early childhood wheezing and their natural courses to help select the most appropriate management modalities for the different types of early childhood wheezing.

• Korean Journal of Child Studies
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• v.35 no.1
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• pp.77-93
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• 2014

The purpose of this research is to develop and evaluate an emotional intervention program for maladaptive preschoolers. The emotional intervention program focused on nurturing the ability to express emotions in healthy ways and how to empathize with others while the preschoolers perceives negative emotions. The participants in this study were nineteen preschoolers, residing in S city. Nineteen subjects were assigned to an experimental group practicing an emotional intervention program. The preschoolers participated in 8-session programs once a week over the course of eight weeks. Descriptive statistics, paired t-test and hierarchical cluster analysis were performed. The results of this study were as follows. First, there were significant differences between posttests and pretests results. The results showed a decrease in maladaptive preschooler's problematic behaviors and aggressive strategies. The maladaptive preschoolers showed more representations of anxiety, avoidance/withdrawal, and deregulated/aggression. In addition the results also showed a decrease in preschooler's representations of anxiety, avoidance/withdrawal, and deregulated/aggression.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.135-138
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• 2005

Since a ductile coupled shear wall system is the primary seismic load resisting systems of many structures, a coupling beams of these system must exhibit excellent ductility and energy absorption capacity. In this paper, the seismic response of coupled shear wall system is discussed. It includes that the evaluation of the degree of coupling between the shear walls and the coupling beams. It is demonstrated through a review of experimental investigations of coupling beam behavior that often the coupling beam ductility demand exceeds the expected available ductility. As a result, it is possible that coupled shear wall system will not behave as desired in the course of a significant seismic event. Limits to the allowable degree of coupling are proposed as a remedy to this apparent deficiency.

• Journal of the Korean Data and Information Science Society
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• v.19 no.4
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• pp.1419-1427
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• 2008

This paper shows the kernel Poisson regression which can be applied in the claims reserving, where the row effect is assumed to be a nonlinear function of the row index. The paper concentrates on the chain-ladder technique, within the framework of the chain-ladder linear model. It is shown that the proposed method can provide better reserve estimates than the Poisson model. The cross validation function is introduced to choose optimal hyper-parameters in the procedure. Experimental results are then presented which indicate the performance of the proposed model.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.197-214
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• 2006

This study explores factors to facilitate web-based collaborative learning and the effect of learning, based on the PBL(Problem Based Learning) from the constructivist approach in e-learning. A research model, using the key variables such as situations, interactions, and systems, was developed. In order to test this proposed model, experimental design and post-survey was conducted to the learners who took on-line and off-line course with team project. In the research model, situation category was divided into instructor's support, unstructured problem, and self-directed learning. Interaction category was divided into three factors; 'interaction between learners', 'interaction between learner and instructor', and 'interaction between learner and technology'. System category was divided into.monitoring and incentives. As a result, it was found that collaborative learning can be improved by situations, interactions, and systems, and the effectiveness of learning can be improved by situations and interactions in PBL.

• Journal of Korean Elementary Science Education
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• v.23 no.1
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• pp.17-26
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• 2004

The purpose of this study is to verify the effect of science-play activity that isn't easily completed in a course of study, put in practice an development activity class on the scientific inquiry skills and the scientific attitude of elementary school students. For this purpose, the general activity was applied for the comparative group (40 students), the science-play activity was applied for the experimental group (34 students); they are composed of 5th and 6th graders elementary school students of 74, a class of an hour during a week. The results were analyzed by means of comparing between groups as well as within groups. The results of this research is as follows: Firstly, the science-play activity as an development activity was effective in the improvement of the scientific attitudes of elementary school students. Secondly, the science-play activity as an development activity was effective in the improvement of the scientific inquiry skills of elementary school students.

• Korean Journal of Veterinary Service
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• v.25 no.3
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• pp.309-314
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• 2002

Recombinant interleukin-2(IL-2) has demonstrated as an antineoplastic agent in mice and human, but the relatively low response rates observed in clinical trials. Therefore, the present study was undertaken in order to evaluate therapeutic activities of IL-2 for the establishment of therapeutic applications. At the onset of the experiment, normal C3H/HeN mice were injected with 5$\times$10$\^$6/ RD-995 tumor cells, murine ultraviolet radiation-induced fibrosarcoma, intraperitoneally. Beginning on day 6, experimental groups were treated with a 5-day course of IL-2(subcutaneous injection of 30,000 IU every 12 hours for 5 days). The result of this experiment revealed that body weight gradually decreased from 20th day in control mice. Subcutaneous IL-2 therapy prevented partially decrease body weight, and prolonged survival of mice compared with control group.

• Journal of the Korean Society for Precision Engineering
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• v.8 no.2
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• pp.47-56
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• 1991

The specifications needed for the mobile cranes are summarized as the following : 1) there may be not occured the oscillation of the cargo at unloading point. 2)the required time from departure point to destination point may be as short as possible. 3) there may be not a collapse of cargo caused by the oscillation in the course that the crago is mobilling. In this paper, the linear fractional transformation method is adopted as a method in order to improve the above mentioned problems. A design method of servo system is developed by modifying Davison's method for the case that the homogeneous differential equations of reference input and disturbance are different types. The real time control of a mobile crane system is implemented by 16bits microcomputer with A/D and D/A converters to illustrate the application of the adopted method. The experimental results for the three types of the design methods; linear fractional transformation method, servo system design method and optimal control method are shown for the comparison.