• Structural Engineering and Mechanics
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• v.55 no.4
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• pp.885-900
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• 2015

This paper introduces Romberg-Richardson's method as one of the numerical integration tools for computation of stress intensity factor in a pre-cracked specimen subjected to a complex stress field across the crack faces. Also, the computation of stress intensity factor for various stress fields using existing three methods: average stress over interval method, piecewise linear stress method, piecewise quadratic method are modified by using Richardson extrapolation method. The direct integration method is used as reference for constant and linear stress distribution across the crack faces while Gauss-Chebyshev method is used as reference for nonlinear distribution of stress across the crack faces in order to obtain the stress intensity factor. It is found that modified methods (average stress over intervals-Richardson method, piecewise linear stress-Richardson method, piecewise quadratic-Richardson method) yield more accurate results after a few numbers of iterations than those obtained using these methods in their original form. Romberg-Richardson's method is proven to be more efficient and accurate than Gauss-Chebyshev method for complex stress field.

• Journal of Surface Science and Engineering
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• v.36 no.1
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• pp.59-68
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• 2003

Zinc phosphating for cold forming of steel was studied with emphasis on decreasing phosphating temperature. To lower phosphating temperature, some techniques, such as adding Cu ion into bath, using activator in the form of pre-dip, and aeration in bath, instead of using conventional accelerator, namely oxidizing agent, have been tried. It was revealed that phosphating, leading to coatings of improved uniformity and fine crystal size, can be carried out using above techniques at lower temperature (55$^{\circ}C$) compared to conventional phosphating temperature ($80∼90^{\circ}C$). Under present condition, it was seen that optimum concentrations of Cu ion in phosphating bath and activator in pre-dip are 0.015 % (w/w) and 2.0 g/1, respectively. The coating weight was within the range of $\15∼20 g/m^2$. When lubricant was applied into phosphating coatings, the amount of lubricating component (total soap) was found to be$ 6∼10 g/\m^2$ and the lubricated panel revealed excellent lubricating properties.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.2 no.2
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• pp.79-85
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• 2009

This research study and design, implement the digital multi-media description technique of Mashup Web which will be evolved into visible visual structure in form of cooperation studying. This technique is study user connect location information and service using pattern, then this information description technique of Mashup pre-operate inference data by tracking user service data.

• The Journal of KAIRB
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• v.1 no.2
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• pp.30-42
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• 2019

In pharmaceutical clinical trials as human material research, the collection, use, storage and provision of human materials must be in accordance with the criteria stipulated in 「Bioethics and Safety Act」, except in the case that some criteria about it is in the law related to clinical trials such as 「Pharmaceutical Affairs Act」 and 「Enforcement Rule on Safety of Drugs, etc.」 so these take precedence over. Under 「Bioethics and Safety Act」, the core aspect of the legal standard for obtaining informed consent is the use of statutory form . The use of statutory form ensure that both those who obtain informed consent and those who give it can know the contents contained this form as well as recognize its importance. Thus, the person who has the right to informed consent can sign the statutory form after correct understanding of the contents. In reality, however, some researchers and IRB members determine that only the main informed consent form is to be used because most of contents on statutory from are included in the main informed consent form. Some other researchers and IRB members judge that the use of statutory form is not needed if human materials may only be used for laboratory testing and the rest will not be stored and provided for future use. Most of these determination and judgement is based on the interpretation of the Korea National Institute for Bioethics Policy(hereafter, KoNIBP) on IRB Information Portal Site. But, it is questionable whether the KoNIBP's interpretation is legally valid and the KoNIBP is the legal entity having authority to interpret existing statute. In some cased not only using the main informed consent form including enough information about the collection, use, storage and provision of human materials but also collecting necessary minimum human materials, and discarding the rest, unusing the statutory form may not cause the problem to respect and protect the research participant's rights. Therefore, the provision stipulating the criteria about the use of statutory form as the legal standard of obtaining informed consent that applies all human material research without exception should review to revise. At least, straighten out the confusion surrounding whether or not the statutory form is to be used, before the revision of related provision, considering the logical opinions of some researchers and IRB Members, the Ministry of Health and Welfare as the legal entity having authority to interpret existing statute should represent its opinion about permission of the acceptable exceptions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.208-217
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• 2017

This study was conducted to identify the influence of awareness regarding marriage and childbirth on pre-parent's role of the nursing students. The subject were 202 nursing students in B city. Data were collected from May 11 to 15, 2015 and analyzed by t-test, ANOVA, Scheffe's test, Pearson correlation coefficients and stepwise multiple regression. Significant differences were found in pre-parent's role based on economic status, ideal number of children, and desired number of children. Pre-parent's role was negatively correlated with romantic views regarding marriage and passive views on marriage. In addition, there was a positive correlation between pre-parent's role and the attitudes towards childbirth support by the nation and corporations. Meaningful variables that influenced pre-parent's role were ideal number of children, economic status and passive views on marriage. Total explanation power was 26.9% and attitudes towards childbirth as well as toward support by the nation and corporations was the most influential factor. To enhance pre-parent's role of nursing students, it is necessary to provide childbirth support by the nation and corporations in the form of financial assistance and childcare facilities, as well as to develop educational programs describing the pre-parent's role.

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.1
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• pp.132-135
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• 2005

The purpose of this study was to propose the modified strip crown technique for esthetic restoration of primary anterior teeth using glass fibers. Celluloid crown form(3M, USA), Z100(P shade, 3M, USA). Aeliteflo(Bisco Inc., USA), and Clearfil SE Bond(Kuraray Medical Inc., Japan) were used for this technique. Mesh type of glass fiber(TESCERA Fiber Mesh, Bisco Inc, USA) was used for reinforcing material. After trimming the celluloid crown form, resin adhesive and flowable resin were applied on the pre-shaped glass fiber mesh. That mesh was placed on the lingual surface of inside of celluloid crown form and followed by light activation. Composite resin was filled into the celluloid crown form and put it on a prepared tooth and then light activated and finished the margin. The new modified strip crown technique can provide esthetics and increased durability for restoration of primary anterior teeth.

• Communications of Mathematical Education
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• v.24 no.2
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• pp.283-300
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• 2010

It has been recognized for a long time that high school students have difficulty in properly interpreting the form $0^0$. The treatment of $0^0$ was still a subject of a slight controversy among mathematicians until relatively recently. Since the mathematics curriculum in high school does not provide the definite treatment of $0^0$, some students might be inclined to ask what the value of the form is. In this research, we review materials dealing with $0^0$ and analyze historically and mathematically the form, whose true meaning is an indeterminate form. We identify the reality of the mathematics education in high school by conducting simple surveys targeting some high school teachers and the students who graduated from high schools recently. Then we discuss, for teachers and pre-service teachers, how to teach the form $0^0$ in high school mathematics.

• The Korea Journal of Herbology
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• v.29 no.4
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• pp.61-67
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• 2014

Objectives : To present a differential standard of Armeniacae Semen and Persicae Semen that are easily confused. Methods : It was planed a differential standard form through outer appearance of the original plant, outer appearance in the form of each medicines and the appearance of the interior form through a microscope for each samples. Using an standard compound amygdalin, each samples have been analyzed by HPLC and TLC. Results : It was possible to distinguish the orignal plant between Armeniacae Semen and Persicae Semen through its leaf shape and calyx type. In Outer appearance in the form of each medicines, there was no difference pre-existing method(measuring length and width). In vascular pattern of the surface, however, there was a clear difference that Armeniacae Semen was developed more reticulated branches than Persicae Semen. In appearance through a microscope, it has not been possible to find a clear difference in the per original plant. However, there was a clear difference between Armeniacae Semen(1 layer) and Persicae Semen(3 layer) in inner albubemen cell. In TLC analysis, there was no difference in the pattern between samples. But in HPLC analysis, Armeniacae Semen showed amygdalin content higher on average. Conclusions : It will be possible to find various differences in the outer appearance of the original plant, the outer appearance in the form of each medicines, the appearance of the interior form through a microscope and physical and chemical research component.

• English Language & Literature Teaching
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• v.18 no.1
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• pp.171-195
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• 2012

While noticing that there is insufficient interest in the assessment of EFL learners' vocabulary levels or sizes, the researchers developed two tests identical in form (Forms A and B) to assess the lexical knowledge of Korean university learners at the $1^{st}{\sim}10^{th}$ 1,000 word bands by adapting a pre-established vocabulary levels test (VLT). Of equal concern was to investigate if the VLT was equally a valid and reliable instrument to be used on measuring the lexical knowledge of EFL learners. The participants were 804 university freshmen enrolled in a General Education English Course from four different colleges. The learners were asked to respond to either Form A or B. While scores generally fell towards the lower frequency bands, multiple regression found the Korean College Scholastic Ability Test (CSAT) to be a significant variable for predicting the learners' vocabulary sizes. From a methodological perspective, however, noticeable differences between Forms A and B could be found with item response theory analysis. The findings of the study provide suggestions on how future VLT for testing EFL learners may have to be redesigned.

• 한국전산유체공학회:학술대회논문집
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• 2000.10a
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• pp.9-14
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• 2000

Computational methods can be classified roughly into two parts: one is the methods based on a potential flow theory, and the other is numerical solvers(CFD) based on Navier-Stockes equation. Methods based on a potential theory are more effective than CFD when the free surface effect is considered. Especially Rankine source method seems to become widespread for simulations of wave making problems. For computations of viscous flow problems, CFD techniques have rapidly been developed and have shown many successful results in the viscous flow calculation. Present paper introduces a computational system 'WAVIS' which includes a pre-processor, potential ant viscous flow solvers and a post-processor. To validate the system, the calculated results for modem commercial hull forms are compared with measurements. It is found that the results from the system are in good agreement with the experimental data, illustrating the accuracy of the numerical methods employed for WAVIS.