• Journal of Digital Convergence
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• v.20 no.1
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• pp.33-39
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• 2022

This study aims to investigate the online class preference depending on students' gender and school level. To achieve this aim, the study conducted a survey on 4,803 elementary, middle, and high school students in 17 regions nationwide. The valid data of 4,524 were then analyzed using the Apriori algorithm to discern the associated patterns of the online class preference corresponding to their gender and school level. As a result, a total of 16 rules, including 7 from elementary school students, 4 from middle school students, and 5 from high school students were derived. To be specific, elementary school male students preferred software-based classes whereas elementary female students preferred maker-based classes. In the case of middle school, both male and female students preferred virtual experience-based classes. On the other hand, high school students had a higher preference for subject-specific lecture-based classes. The study findings can serve as empirical evidence for explaining the needs of online classes perceived by K-12 students. In addition, this study can be used as basic research to present and suggest areas of improvement for diversifying online classes. Future studies can further conduct in-depth analysis on the development of various online class activities and models, the design of online class platforms, and the female students' career motivation in the field of science and technology.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.25-25
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• 2021

전 세계에 유통되고 있는 Cypripedium속 식물 56종 중 한반도에는 4종이 분포하고 있다. 국내의 Cypripedium속 식물 중 멸종위기 1급 식물은 광릉요강꽃과 털복주머니란이 있으며, 복주머니란은 멸종 위기 2급 식물로 분류하였다. 본 연구는 이러한 복주머니란 식물의 육묘기술을 개발하기 위하여 연구를 수행하였다. 처리는 원예용 상토, 마사토 100%, 질석 2 : 펄라이트 1의 비율로 혼합한 인공토양, 산야초 상토, 소립인 난석 등 5처리를 하여 복주머니를 스티로폼 박스(가로 40, 세로 50, 높이 15cm)에 식재하여 4개월 경과 후 조사한 결과 산야초 상토에서 출아율이 67.0%로 가장 많았으며, 질석 2 + 펄라이트 1의 처리구가 53.0%, 소립인 난석 처리구가 48.0%순으로 높았다. 출아율이 가장 좋았던 산야초 상토의 경우 초장은 3.0cm, 엽수는 주당 1.9개, 엽폭은 1.0cm로 다른 처리구보다 생육이 양호하였다. 또한 털복주머니란 실생묘를 노지에서 1년 동안 순화한 묘를 자생지 외 지역의 적응성을 확인하기 위해 경기도 양평에 위치한 국립수목원 내 Cypripedium 전문 전시원에 660주를 봄에 식재하였다. 그해 9월에 생존율 을 조사한 결과 52.5% 이었고, 초장이 5.8cm, 뿌리수는 주 당 3.6개, 뿌리길이는 6.4cm 등 생육도 정상적으로 진행되는 것으로 조사되었다. 이와같은 연구를 바탕으로 멸종위기종인 복주머니란의 적정 환경 조성과 육묘기술 및 현지 적응성을 향상시킨다면 멀지 않은 시기에 복주머니란의 복원 사업은 성공적으로 마무리될 것으로 판단된다..

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.5
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• pp.257-269
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• 2021

This study aimed to secure basic data for the development and operation of well-aging education programs by analyzing the physical, mental, and socio-economic needs of well-aging education for successful aging. The research tool was developed as a questionnaire to investigate the perception of well aging and the needs of well-aging education in terms of physical, mental, and socio-economic aspects. In February 2021, 1949 adults over the age of 19 were surveyed through an online and mobile survey by Gallup Korea. Descriptive statistics analysis, variance analysis, Borich needs analysis, and IPA analysis were conducted to analyze the needs of well-aging education. The results revealed economic power, exercise, and chronic disease management to be high in terms of the overall priority of the education needs for well-aging, and infectious disease management, independence, and social responsibility were surveyed in the order of low education needs. In terms of economic power, education needs were highest among all age groups except for the middle-age group (35-49 years old), 82.4% of all respondents, and education needs for exercise and chronic disease management were highest in the middle-age group. Therefore, it is necessary to develop well-aging education programs for each life cycle. These results are expected to be used as empirical data in establishing a platform for developing and operating educational programs for well aging.

• Investigative Magnetic Resonance Imaging
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• v.8 no.2
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• pp.79-85
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• 2004

Purpose : To evaluate the usefulness and reproducibility of $^1H$ MRS in different 1.5 T MR machines with different coils to compare the SNR, scan time and the spectral patterns in different brain regions in normal volunteers. Materials and Methods : Localized $^1H$ MR spectroscopy ($^1H$ MRS) was performed in a total of 10 normal volunteers (age; 20-45 years) with spectral parameters adjusted by the autoprescan routine (PROBE package). In all volunteers, MRS was performed in a three times using conventional MRS (Signa Horizon) with 1 channel coil and upgraded MRS (Echospeed plus with EXCITE) with both 1 channel and 8 channel coil. Using these three different machines and coils, SNRs of the spectra in both phantom and volunteers and (pre)scan time of MRS were compared. Two regions of the human brain (basal ganglia and deep white matter) were examined and relative metabolite ratios (NAA/Cr, Cho/Cr, and mI/Cr ratios) were measured in all volunteers. For all spectra, a STEAM localization sequence with three-pulse CHESS $H_2O$ suppression was used, with the following acquisition parameters: TR=3.0/2.0 sec, TE=30 msec, TM=13.7 msec, SW=2500 Hz, SI=2048 pts, AVG : 64/128, and NEX=2/8 (Signa/Echospeed). Results : The SNR was about over $30\%$ higher in Echospeed machine and time for prescan and scan was almost same in different machines and coils. Reliable spectra were obtained on both MRS systems and there were no significant differences in spectral patterns and relative metabolite ratios in two brain regions (p>0.05). Conclusion : Both conventional and new MRI systems are highly reliable and reproducible for $^1H$ MR spectroscopic examinations in human brains and there are no significant differences in applications for $^1H$ MRS between two different MRI systems.

• Journal of the Korean Society of Marine Environment & Safety
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• v.24 no.5
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• pp.628-636
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• 2018

Because large buoys are mainly made of steel, they are heavy and vulnerable to corrosion by sea water. This makes buoy installation and maintenance difficult. Moreover, vessel collision accidents with buoys and damage to vessels due to the material of buoys (e.g., steel) are reported every year. Recently, light buoys adopting eco-friendly and lightweight materials have come into the spotlight in order to solve the previously-mentioned problems. In Korea, a new lightweight buoy with a 7-Nautical Mile lantern adopting expanded polypropylene (EPP) and aluminum to create a buoyant body and tower structure, respectively, was developed in 2017. When these light buoys are operated in the ocean, the visibility and angle of light from the lantern installed on the light buoys changes, which may cause them to function improperly. Therefore, research on the performance of light buoys is needed since the weight distribution and motion characteristics of these new buoys differ from conventional models. In this study, stability estimation and motion analyses for newly-developed buoys under various environmental conditions considering a mooring line were carried out using ANSYS AQWA. Numerical simulations for the estimation of wind and current loads were performed using commercial CFD software, Siemens STAR-CCM+, to increase the accuracy of motion analysis. By comparing the estimated maximum significant motions of the light buoys, it was found that waves and currents were more influential in the motion of the buoys. And, the estimated motions of the buoys became larger as the sea state became worser, which might be the reason that the peak frequencies of the wave spectra got closer to those of the buoys.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.303-313
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• 2020

Rice grain shape is one of the key components of grain yield and market value. An understanding of the genetic basis of the variation in grain shape could be used to improve grain shape. In this study, we developed a total of 265 F₂ individuals derived from a cross between japonica cultivars (Josaeng-jado and Langi) and used this population for quantitative trait locus (QLT) analysis. Correlation analysis was performed to identify relationships between grain traits (GL: grain length, GW: grain width, L/W: ratio of length to width, TGW: 1,000 grain weight). The grain shape was positively correlated with GL and TGW, and negatively correlated with GW. In QTL analysis associated with grain shape, one QTL for GL, qGL5, detected on chromosome 5, explained 20.3% of the phenotypic variation (PV), while two QTLs, qGW5 (PV=36.1) and qGW7 (PV=26.1), for GW were identified on chromosomes 5 and 7, respectively. Evaluation of the effects of each of the QTLs on the grain shape in the population showed a significant difference in the grain size in positive lines compared with the lines without the QTLs. According to the QTL combination of the allelic-types, the grain shape of the tested lines varied from semi-round type to long spindle-shaped type. The results of this study extend our knowledge about the genetic pool governing the diversity of grain shape in japonica cultivars and could be used to improve the grain shape of this species through marker-assisted selective breeding in Korea.

• Journal of Korean Society of Forest Science
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• v.105 no.2
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• pp.193-201
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• 2016

This study was carried out to analyze the nutritional composition, bioactive components, antioxidant activity, and cytotoxic assay of cancer cells on Rubus crataegifolius (RC) : R. crataegifolius from Jangseong (RC-J), R. crataegifolius from Hwaseong (RC-H), R. crataegifolius from Ulsan (RC-U), R. crataegifolius from Sunchang (RC-S), and R. crataegifolius from Pohang (RC-P). The peroximate composition had the largest amount of carbohydrate content among all kinds of RC. As far as the mineral contents of RC, Calcium comprised the highest amount ($996.6{\mu}g/g{\pm}0.8%$) and Natrium the lowest ($6.2{\mu}g/g{\pm}1.0%$). A total of 26 kinds of free amino acids and 18 kinds of component amino acids were analyzed in RC. The results of electron donating were high scavenging effects of 80% in water extract (RC-UW) and 82.6% in ethanol extract (RC-UE) in $500{\mu}g/ml$ concentration from RC-U. Also, the cytotoxic effects of cancer cells B16F10 (RC-UW and RC-PE), H1299 (RC-SW and RC-PE), and MCF-7 (RC-JW and RC-SE) appeared in RC. Therefore, we confirmed that new varieties may possibly be developed with functional materials.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.75-84
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• 2008

Colored potatoes are an excellent source of dietary polyphenols including anthocyanins. Generally, anthocyanins from fruits and vegetables exhibit anti-carcinogenesis and anti-cancer properties in vitro test. This experiment was conducted to know the effects of colored potato extracts contained anthocyanins on antimutagenic activity and anticancer activity to six human cancer cell lines containing LNCaP (androgen-dependent) prostate cancer cells. Extracts of three colored potatoes ('Hongyoung', 'Jayoung' and 'Jasim') and the white potato ('Superior') cultivars were used in this study. The extracts of three colored potatoes inhibited the mutagenicities induced by direct mutagen such as 4-nitro-quinoline-1-oxide (4-NQO) and another indirect mutagens of bezo(a)pyrene (BaP). Also, the extracts of 'Hoyoung' and 'Jayoung' showed higher antimutagenic activity than 'Jasim' and 'Superior' against to direct or indirect mutagen on both strains of TA98 and TA100. The activity of growth-inhibitory of extract of four potato cultivars were screened by SRB (sulphorhodamine B) method on diverse human cancer cells representing different types of cancers. Among the extract of four potato cultivars, the extract of 'Jasim' showed moderate inhibition on proliferation of LNCaP, ACHN and MOLT-4F cells and did not inhibit the proliferation of other cancer cells. On the other hand, extract of 'Superior' did not inhibit the proliferation of any tested cancer cell lines. However, the extracts of 'Hongyoung and Jayoung' inhibited the proliferation of cancer cells with $GI_{50}$ values ranging from 2.5 to $30\;{\mu}g/mL$. On the basis of the $GI_{50}$ values, it is clear that LNCaP cells were more sensitive to extracts of colored potato cultivars than other cancer cells. The extract of 'Jayoung' at $30\;{\mu}g/mL$ were more active and inhibited cell proliferation, and induced apoptosis in LNCaP cells. This result revealed that the extracts of colored potatoes are expected to be good candidate for development into source of antimutagenic and anticancer agent.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.2
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• pp.221-233
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• 2019

In Korea, small and medium sized domestic enterprises(SMEs) play an pivotal role in the national economy, accounting for 99.9% of all enterprises, 87.9% of total employment, and 48.3% of production. and SMEs was driving a real force of the development of national economy in many respects such as innovation, job creation, industrial diversity, balanced regional development. Despite their crucial role in the national development, most of SMEs suffer from a lack of R&D capabilities and equipments as well as funding capacity. Public R&D institutes can provide SMEs with valuable supplementary technological knowledge and help them build technological capacity. so, In order to effectively support SMEs, government and public R&D institutes must be a priority to know about the factors influencing the performance related to technology transfer and technological collaborations. In particular, SMEs are not only taking up a large portion of the national economy, but also their influence in politics and economy so strong that raising the competitiveness of small and medium-sized companies is a national policy goal that must be achieved in order to achieve sustained economic growth. For this reason, it is necessary to look specifically at the relationship between concepts such as the environment, strategy, and organizational culture surrounding the enterprise to enhance the competitiveness of SMEs. The paper analyzes 665 companies to find out which organizational culture affects their performance by classification and type of business of SMEs. This study demonstrated that when SMEs seek consistency in their external environment, strategies, and organizational structure to maintain their continued competitiveness. According to three-way analysis of variance (3-way ANOVA) indicates that classification of industries in SMEs has statistically significant main effects, but the type of business and organizational culture do not have significant effects. However, the company's organizational performance (operating profit) of SMES were found to differ significantly in comparison between groups according to classification standards of industries, and therefore adopted some parts. In addition, an analysis of the effect of interaction between the three independent variables of small and medium-sized enterprises has shown that there are statistically significant interaction effects among classification, types of business, and organizational cultures. The results shows that there is an organizational culture suitable for each industry classification and type of business of an entity, and is expected to be used as a basis for establishing promotion policies related to the incubation and commerciality of small and medium-sized venture companies in the future.

• Journal of the Korean Society for information Management
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• v.41 no.1
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• pp.465-486
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• 2024

The purpose of this study is to identify the current status of infrastructure and services for analyzing research data for research data managers at government-funded research institutions under the National Research Council for Science and Technology (NST) who will actually use the Korea Research Data Commons (KRDC), which is being developed by the Korea Institute of Science and Technology Information (KISTI) and to investigate the perceptions of research data managers related to the establishment of KRDC system. For the study, we conducted a survey targeting 24 government-funded research institutes, excluding KISTI, and interviewed research data managers from 9 of the 15 institutions surveyed who agreed to follow-up interviews. As a result of the survey, most institutions were providing related services, and their willingness to introduce an integrated analysis framework for the use of research data and provide a system for using externally released analysis software was also high. Meanwhile, when we investigated the external disclosure status of each institution's analysis services through follow-up interviews, only a minimal number of institutions were disclosing them to the outside world. The findings reveal that there is a demand to utilize analysis infrastructure and services when provided through the framework. However, it is difficult to disclose and share the analysis resources held by each organization. In order to establish the KRDC system, it is essential to share research sites' analysis infrastructure and services, and in addition, changes in the perception of research sites and institutional changes are necessary. Furthermore, there is a need to establish policies that consider the system's convenience, security, and compensation system raised in the follow-up interviews.