• East Asian mathematical journal
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• 제33권2호
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• pp.177-197
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• 2017

The purpose of this study is to investigate and analyze the understandings of elementary pre-service teachers about 'estimation' in the elementary mathematics. Together with this analysis, we identify elementary pre-service teacher's Mathematical Pedagogical Contents Knowledge(MPCK), especially focusing to Subject Matter Knowledge(SMK). In order to this goals, we investigate contents relating to 'estimation' from $1^{st}$ curriculum to 2009 revised curriculum and compare 'rounding up', 'rounding off', 'rounding' in the elementary mathematics textbooks. As results of investigations, 'estimation' has been teaching at the 'Measurement' domain from $3^{rd}$ curriculum, but contexts of measuring weaken from $7^{th}$ curriculum. 'Rounding up(off)' is defined three types in the textbooks from $1^{st}$ to 2009 revised curriculum. And we examine elementary pre-service teachers through the questions on these 'estimation' contents. On the analysis of pre-service teacher's understanding relating MPCK, four themes is summarized as followings; the understanding of '0' in the 'rounding up', the cognitive gap between 'rounding up' and 'rounding off', the difference of percentage of correct answers according to types of question in the 'rounding up', and the difference between the definition of 'rounding up' and the definition of 'rounding'.

• 한국초전도ㆍ저온공학회논문지
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• 제5권1호
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• pp.31-34
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• 2003

Bi-2223 superconducting wires with 55 filaments were fabricated by stacking, drawing process with different heat-treatment histories. Two kinds of powders were prepared. One was pre-annealed at 760-820 $^{\circ}C$ and low oxygen partial pressure, and the other was only calcined state. Before rolling process, round wires were pre-annealed at 760 -820 $^{\circ}C$ and in a low oxygen partial pressure. We confirmed that pre-annealing step was to transform Bi-2212 orthorhombic structure from Bi-2212 tetragonal structure and to reduce the formation of second phases at superconducting wire. However Bi-2223 phases were formed at higher pre-annealing temperature. Bi-2223 conductor was needed frequently annealing at low temperature because pre-annealing at precursor powder brought about decrease in workability. We could achieve highest Je of 6500 A/$\textrm{cm}^2$ at the tape using Bi-2212 orthorhombic phase by introduced slightly overheating at the 1st sintering process.

• 한국생활과학회지
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• 제21권1호
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• pp.113-128
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• 2012

The purpose of this study was to identify key components in developing educational programs designed to enhance pre-service teachers' professionalism. Key program characteristics identified and implemented through this study are as follows: First, programs should provide opportunities for trainees to reflect on goal identification and setting goals as professional teachers. Second, programs should emphasize the relationship between the pre-service teachers' personal qualities and professional development. Third, programs should include and integrated and holistic approach to integrating content and teaching methodology. Fourth, the program's educational content should unfold in a gradual and sequential manner. Fifth, the program should support a strong relationship between senior teachers and juniors pre-service teachers. Sixth, the program should take advantage of the physical and human resources in the pre-service teacher's community. Seventh, the program should employ circular and formative evaluation of contents and teaching methods as a way of facilitating development and improvement. This study develops and demonstrates an extensive model program that fits these criteria. Also included is discussion related to further studies.

• The Journal of Asian Finance, Economics and Business
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• 제7권1호
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• pp.279-290
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• 2020

Informal networks between individuals are widely seen as important in East Asian business systems. However, while the performance implications of guanxi in China have been extensively studied, much less is known on how informal networks may influence business outcomes in other East Asian countries. We examine informal networks in inter-organizational research collaborations in South Korea by studying the role of pre-existing social ties and relational orientation in new product development (NPD) collaborations and university-industry research (UIR) collaborations. We conduct an interview-based, in-depth case analysis of five NPD collaborations and five UIR collaborations. Pre-existing social ties and relational orientation are prevalent in both types of research collaborations. However, they have different consequences for collaboration outcomes. Pre-existing social ties strongly vary in their types and strength, and negatively affect collaboration outcomes unless they result in the selection of competent and motivated partners. Relational orientation manifests itself in a task-related and social exchange between collaboration partners, which contributes to outcomes such as knowledge acquisition and business performance. Korean collaboration managers should rely only on pre-existing social ties that are well-aligned with task-related requirements when initiating and conducting research collaborations. However, the creation of strong relationships between collaboration team members of partnering organizations should be encouraged.

• Steel and Composite Structures
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• 제13권1호
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• pp.71-89
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• 2012

The paper investigates beam lateral buckling stability according to linear and non-linear models. Closed form solutions for single-symmetric cross sections are first derived according to a non-linear model considering flexural-torsional coupling and pre-buckling deformation effects. The closed form solutions are compared to a beam finite element developed in large torsion. Effects of pre-buckling deflection and gradient moment on beam stability are not well known in the literature. The strength of singly symmetric I-beams under gradient moments is particularly investigated. Beams with T and I cross-sections are considered in the study. It is concluded that pre-buckling deflections effects are important for I-section with large flanges and analytical solutions are possible. For beams with T-sections, lateral buckling resistance depends not only on pre-buckling deflection but also on cross section shape, load distribution and buckling modes. Effects of pre-buckling deflections are important only when the largest flange is under compressive stresses and positive gradient moments. For negative gradient moments, all available solutions fail and overestimate the beam strength. Numerical solutions are more powerful. Other load cases are investigated as the stability of continuous beams. Under arbitrary loads, all available solutions fail, and recourse to finite element simulation is more efficient.

• 농업과학연구
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• 제37권1호
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• pp.131-141
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• 2010

This paper aims to review how pre-processing facility of agricultural products can be established and operated. First of all, industry and its enterprises of pre-processing agricultural products are analyzed from the national perspective. Especially, five well-known pre-processing business units operated by producers' organizations are introduced including Ansung Machoom Agricultural Cooperative. Changwon City in Gyeongnam Province was chosen for a case study. Demand for local agricultural products by school feeding and other institutional food service in Changwon area is estimated and it is compared with the supply of agricultural products produced in the region. Questionnaire survey was done for school nutritionists and the main results are summarized. In the final stage, basic ideas for pre-processing facility of agricultural products in Changwon area are proposed considering the previous analyses. These ideas include size of the facility, participants and scope of the business, and location. Virtual profitability analysis is also conducted for the facility. Some suggestions for the proposed facility to be more successful in the future are suggested at the conclusion.

• Journal of Ginseng Research
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• 제34권2호
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• pp.93-97
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• 2010

To enhance the functionalities of ginseng, an acid impregnation pre-treatment was applied during red ginseng processing. Acetic, ascorbic, citric, malic, lactic, and oxalic acid were used for the acid impregnation treatment, and total and crude saponin concentrations and ginsenoside patterns were evaluated. Total and crude saponin contents of red ginseng pre-treated by acetic, ascorbic, and citric acid were similar to those of red ginseng without pre-treatment, whereas lactic, malic, and oxalic acid pre-treatment caused a reduction of total and crude saponin in red ginseng. From the high performance liquid chromatography analysis of ginsenosides, increased $Rg_3$ density was shown in red ginseng pre-treated by acetic, ascorbic, and citric acid impregnation. In the case of lactic, malic, and oxalic acid pre-treatment, increased $Rg_1$ density was observed in red ginseng. Increased $Rg_1$ and $Rg_3$ contents due to acid impregnation during red ginseng processing may contribute to improving bioactive functionalities of red ginseng.

• 대한물리치료과학회지
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• 제11권1호
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• pp.5-13
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• 2004

The purpose of this study was to the Pre-Post maximal exercise for analyze the Physiological Variable(Lactate, LDH, Glucose) in the runners. The subjects were 12 volunteers 6 sprinters and 6 distance runners who agreed to intention of this study. Subjects performed until possible all-out trials. Blood samples were taken from a median cubital vein Pre-Post exercise and every rest 5min during the all-out trial. The results obtained were summarized as follow ; 1) Lactate of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, but showed significant in sprinters and distance respectively 2) LDH of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and that showed no significant in sprinters and distance respectively 3) Glucose of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and showed no significant in distance, but showed significant in sprinters therefor, since the runners has an intermittent characteristic which includes a frequent momentary change, it needs the fitness training that being consisted of various training, in the training method, it needs the training process which is from the whole fitness to specific fitness to improve general physical ability.

• 한국염색가공학회지
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• 제18권1호
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• pp.1-9
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• 2006

Treatment of PET fabrics with alkali, chitosan and Al-mordanting has been carried out and the role of the chitosan coating in the dyeing process was clarified. The pre-treatment was effectively evaluated differences in dyeing behavior between its treated and untreated PET fabrics using wood of Caesalpinia sappan. The pre-treated on PET fabrics has been examined by SEM and evidence for the presence of chitosan sought using a air permeability test. Similar colour fastness by computer color matching(CCM) obtained on both untreated and pre-treated PET fabrics. The pre-treated PET was found to be of a deeper hue to that of its dyed untreated PET and, despite of its better colour depth, the wash fastness of the pre-treated dyeing was comparable to that of its dyed untreated PR. The application of chitosan or mordanting reveled that pre-treatment imparted to the PET additional functional groups that were available for coordination with the Brazilin.

• 한국의상디자인학회지
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• 제17권2호
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• pp.45-61
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• 2015

In order to analysis on color difference of natural dyes, I have dyed Hanji, cotton, silk fabric and exposed them to carbon arc light. The results of experiment have been analysed by wavelength of maximum absorption, amounts of dye uptake, color difference, Hunter's value and Munsell's value. Gardenia Jasminoides is monogenetic dye, but it gained darker color by pre-mordanting method used Al mordant agent and greenish yellow color by Fe mordant agent. whereas Curcuma, an Amur cork, and bud of pagoda tree are shown as greenish yellow color, and A barberry root, Betel nut, and Rhubarb are shown as reddish yellow color. these gained khaki colored dyed fabric by Fe mordanting. In addition, Sappan wood showed great result in pre-mordanting. Especially, it gained dark red color by Al pre-mordanting. The pink color was shown by post-mordanting. and Logwood showed great dyeing result in Hanji and cotton better than silk. Specially pre-mordanting was effective. Hanji and cotton showed greenish blue color by Al pre-mordanting, and silk showed brown color.