• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.10 no.1
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• pp.47-54
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• 2004

Normally, the single wall(SW) corrugated board has more advantages than double wall (DW) corrugated board in terms of the cost of the materials and logistics. For instance, the SW corrugated board has 3 layer papers whereas the DW corrugated board has 5 layer papers. The thickness of the SW is about 5mm, but that of the DW is 8mm. Accordingly, the SW corrugated board is quite more used in the developed countries than the DW corrugated board. But in Korea, the DW corrugated board is quite more used. The reason why more DW corrugated board are used than the SW corrugated in Korea is that in order that the SW corrugated board has the same box compression strength as DW corrugated board, the cost of the SW corrugated board is higher than that of the DW corrugated board because the virgin kraft liners are all imported from overseas. In this study, the physical properties such as flat crush strength and column crush strength of typical SW corrugated board and single wall dual-layer medium corrugated board and their costs were analyzed. The analysis resulted in that single wall dual-layer medium corrugated board has the same thickness as the SW corrugated board but the more flat crush strength and column crush strength and the less cost than the SW corrugated board.

• Environmental Engineering Research
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• v.24 no.3
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• pp.449-455
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• 2019

To investigate the effect of seaweed (SW) addition on anaerobic co-digestion of food waste (FW) and sewage sludge (SS), batch experiments were conducted at various substrate concentrations (2.5, 5.0, 7.5, and 10.0 g volatile solids (VS)/L) and mixing ratios ((FW or SS):SW = 100:0, 75:25, 50:50, 25:75, and 0:100 on a VS basis). The effect of SW addition on FW digestion was negligible at low substrate concentration, while it was substantial at high substrate concentrations by balancing the rate of acidogenesis and methanogenesis. At 10 g VS/L, $CH_4$ production yield was increased from 103 to $350mL\;CH_4/g$ VS by SW addition (FW:SW = 75:25). On the other hand, SW addition to SS enhanced the digestion performance at all substrate concentrations, by providing easily biodegradable organics, which promoted the hydrolysis of SS. $k_{hyd}$ (hydrolysis constant) value was increased from 0.19 to $0.28d^{-1}$ by SW addition. The calculation showed that the synergistic $CH_4$ production increment by co-digesting with SW accounted for up to 24% and 20% of total amount of $CH_4$ production in digesting FW and SS, respectively.

• Journal of The Korean Association of Information Education
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• v.25 no.2
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• pp.377-385
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• 2021

This study attempted to develop and apply a physical computing SW education program applying design thinking. The produced SW education program was applied to 22 students in the 5th and 6th grades of J and B elementary schools located in Jeju-si. Computational thinking ability and creativity pre-test was conducted, and Physical computing software training applied design thinking was conducted over a total of 5 sessions for 20 hours, followed by a post-test on creativity and computational thinking ability. As a result of the verification, it was found that physical computing SW education program applying design thinking was effective in improving the creativity and computing thinking ability of elementary school students.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.171-177
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• 2012

A total of 94 tomato accessions were evaluated for the resistance to $Tomato$ $spotted$ $wilt$ $virus$ (TSWV) using a Sw5-2 SCAR marker and bioassay. PCR products of the marker were approximately 574 bp, 500 bp, and 462 bp, among which the longest was linked to TSWV resistance allele of Sw5-b. This allele was only found in three accessions (09-438, 10-318, and 10-321) in which some individuals showed apparent recovery or stem necrosis symptom to a tomato isolate of TSWV-pb1. Thirty-five individuals (one per each accession) which were non-infected by ELISA were selected for further observation. Among these, 26 individuals that did not show any symptom at 5 months after inoculation were confirmed for viral infection by RT-PCR. TSWV-specific PCR amplicon was weakly detected in all 26 individuals including 'Eureta', a commercial F1 possessing the resistance allele of Sw5-b. The resistant genes in the selected individuals may play an important role for reducing the viral concentration in tissues of inoculated tomato plants and seems to be quantitatively controlled by several factors including Sw5-b gene.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.302-307
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• 2014

Many rhizobacteria can promote plant growth through various direct or indirect mechanisms, and their production of phytohormones such as indole-3-acetic acid (IAA) may have pronounced effects on growth and development of plants. Rhizobacterial strain isolated from rhizosphere of foxtail (Setaria viridis), Acinetobacter sp. SW5 produced 118.1 mg/L of IAA and 4.5 mg/L of gibberellin ($GA_3$) in brain heart broth medium at 2 and 1 day of incubation, respectively. In a pot test the lengths of stem and root and fresh weight of the germinated tomato seedlings treated with Acinetobacter sp. SW5 significantly increased by 26.3, 33.3, and 105.3%, respectively compared to those of the uninoculated control in 12 weeks of cultivation. When the root exudate secreted from tomato seedlings was analyzed by HPLC, 3.75 ng mg tomato $root^{-1}$ of tryptophan which is an IAA precursor was detected. Acinetobacter sp. SW5 could produce $4.06{\mu}M$ of IAA from root exudate from 8 tomato seedlings. Together with the capability of growth of Acinetobacter sp. SW5 in the tomato root exudates, this IAA secreted by bacteria might contribute to enhance the growth of tomato plants.

• Journal of the Korean Society for Railway
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• v.15 no.5
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• pp.442-446
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• 2012

This paper is a practical study on the development of SEMP template using SE & SW infrastructures. SEMP, which is a management system for systems engineers, has been developed for the LRT(Light Rail Transit) industry and has been tailored to suit domestic conditions. SE & SW infrastructures were developed to assist in creating an effective and efficient SEMP for the industry of this study. This paper proposes a method to reduce costs, manpower, and time for the LRT industry using SEMP based on SE & SW infrastructures.

• Journal of Digital Convergence
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• v.18 no.5
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• pp.55-63
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• 2020

Recently, there is a strong interest in SW basic education for non-major students in universities, but SW non-majors are having a hard time learning. This paper proposes a class operation method that utilizes customized contents reflecting the interests of non-majors, rather than using existing learning contents for SW majors. The proposed method is to improve the education effects by increasing the learning motivation of SW non-majors. The paper shows a case study of A university, which has operated non-major SW basic education for more than five years. The case study analyzed the change of class satisfaction of students of pre- and post- learning group that reformed major-friendly contents about the same curriculum. As a result, the students of social sciences are interested in learning contents using public data that can examine the social and cultural phenomena of the country, and humanities students are interested in text contents such as novels, history books, and SNS articles. In addition to the understanding of the lectures, the class satisfaction was also greatly improved, and it showed that the major-friendly contents is useful for SW basic education of non-majors.

• Journal of Korean Elementary Science Education
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• v.39 no.2
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• pp.296-305
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• 2020

The purpose of this study was to analyse the effects of the SW-STEAM program by utilizing software supporting the creation of VR for elementary science class. Two classes of 5th grade were selected, and were engaged in different teaching and learning methods during 12 class hours. The experimental group which is consisted of 20 students participated in the SW-STEAM program by utilizing software supporting the creation of VR, the comparative group which comprised 19 students was thaught by using a traditional instruction. Teaching unit was 'the solar system and stars' in 5th grade science text book. The results of this study were as follows. The SW-STEAM program by utilizing software the creation of VR had a positive effect on elementary school students' creative problem solving ability, scientific interest, science achievement. Therefore, the SW-STEAM program by utilizing software supporting the creation of VR could be meaningful works to encourage students' creative problem solving ability, scientific interest, science achievement, and this study will help elementary teachers teach 'the solar system and stars' in 5th grade science text book more interesting.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.2-5
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• 2015

본 연구에서는 프로그램을 전혀 해보지 않았고, 게임에는 관심 있는 초등학교 저학년을 대상으로 EPL 도구로서 스크래치를 이용한 SW교육의 교수 학습 모형을 개발하였다. 5단계 10차시로 분류하여 각 단계별 학습목표를 설정하고 교수 학습 목표를 결정하였다. 학습목표에 맞게 각 단계별 수업이 이루어지면 목표에 도달할 수 있도록 반복수업, 흥미 있는 수업, 이해도가 증가할 수 있도록 단계별 수업으로 구성하였다. 또한 SW교육 교수 학습 모형에서 각 차시별 목표를 설정하고 단계별 교수 학습 전략을 제공하여 목표에 도달할 수 있도록 유도하였다. 본 연구를 통해 초등학교 저학년에게 SW교육이 가능한지, 어느 정도 수준의 교육으로 이루어져야 하는 지, EPL 도구로서의 스크래치의 활용성은 어느 정도인지 등을 알아보고 SW교육에 수업자료로 활용하고자 한다.

• Journal of Digital Convergence
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• v.11 no.5
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• pp.1-11
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• 2013

To make the DRM technology protect adequately the copy right of digital contents, DRM software should have high quality and no defects when DRM is added to digital contents. It can be a basis for the effective protection of the copyright of digital contents to develop a quality evaluation model of DRM SW. First of all, the security of DRM SW is the most critical quality characteristic that DRM software must have. In this paper, we conducted research on how to measure the quality of security of DRM SW.