• Title/Summary/Keyword: STEM research

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A Study on the Current Status of the Adoption of Creative Commons Licenses in Korean Citation Index Journals (KCI 등재지의 CCL 적용 현황 연구)

  • Kyoung Hee Joung
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.34 no.2
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    • pp.233-249
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    • 2023
  • This study aimed to understand the application and types of Creative Commons Licenses (CCL) in Korean journals and to increase understanding of the state of open access in South Korea. The study collected and analyzed CCL-related information from the websites of 2,097 KCI journals and compared the findings with DOAJ journals and previous research. The results of the study are summarized as follows. Firstly, 18% (377 journals) of the KCI journals adopted CCL, and among them, approximately 90% (337 journals) were in the field of STEM. There were few academic journals applying CCL in humanities and social sciences fields. Secondly, the types of CCL adopted by KCI journals were NC licenses (90%), with CC BY-NC (85%) being the most common. This is a significant difference from DOAJ journals, where 52% of academic journals applied CC BY or CC BY-SA. However, fewer journals applied licenses of the ND licenses than DOAJ journals and Spanish journals. Thirdly, 44% (167) of the 377 academic journals that applied CCL were simultaneously for free in public databases and sold for a fee in commercial databases. 33% (125) were publicly available for free in public databases, and 9% (33) were sold in commercial databases.

Development of a Single Allocation Hub Network Design Model with Transportation Economies of Scale (수송 규모의 경제 효과를 고려한 단일 할당 허브 네트워크 설계 모형의 개발)

  • Kim, Dong Kyu;Park, Chang Ho;Lee, Jin Su
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.6D
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    • pp.917-926
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    • 2006
  • Transportation Economies of scale are the essential properties of hub networks. One critical property of the hub network design problem is to quantify cost savings which stem from economies of scale, the costs of operating hub facilities and opportunity costs associated with delays stemming from consolidation of traffic flows. Due to the NP-complete property of the hub location problem, however, most previous researchers have focused on the development of heuristic algorithms for approximate solutions. The purpose of this paper is to develop a hub network design model considering transportation economies of scale from the consolidation of traffic flows. The model is designed to consider the uniqueness of hub networks and to determine several cost components. The heuristic algorithms for the developed model are suggested and the results of the model are compared with recently published studies using real data. Results of the analysis show that the proposed model reflects transportation economies of scale due to consolidation of flows. This study can form not only the theoretical basis of an effective and rational hub network design but contribute to the assessment of existing and planned logistics systems.

The Comparative Study on Mental Representation between Foster-care and Typical Children (위탁 아동과 일반 아동의 정신적 표상 비교)

  • Min Jung Go;Kyung Sook Lee;Yun Mi Kim;In Ae Choi
    • Korean Journal of Culture and Social Issue
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    • v.19 no.3
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    • pp.507-528
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    • 2013
  • The study examined the mental representation of children in foster care through the MacArthur Story Stem Battery (MSSB) and reviewed difference between children in foster care and typical children in terms of mental representation. Subjects of the study included a total of 50 children: 25 children (11 boys and 14 girls), aged from 5 to 8, in foster care in Gyeonggi Province, and 25 typical children (11 boys and 14 girls), aged from 5 to 8, who lived in Seoul and Gyeonggi Province. The research findings are summarized as follows: First, in terms of mental representation, children in foster care showed less subjects of empathic relations and more subjects of disorganized aggression than typical children. Second, children in foster care showed lower coherence mental representation than typical children. Finally, children in foster care were more likely to fail in emotional regulation than typical children in mental representation.

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Comparative Analysis of Lighting Intensity, Leaf Temperature, Transpiration Rate, and Vapor Pressure Deficit between the Top and Branching Point of Stem during Growing Period of Paprika Plant (파프리카 생장에 따른 줄기의 정부와 하부 간 광량, 엽온, 증산속도 및 수증기압포차 비교 분석)

  • Seung Mi Woo;Ho Cheol Kim
    • The Journal of the Convergence on Culture Technology
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    • v.9 no.6
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    • pp.1097-1101
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    • 2023
  • As paprika plants grew in a glass greenhouse from November 2022 to March 2023, the amount of light at each plant height, leaf temperature, transpiration rate, and water vapor pressure were measured. Accumulated leaf temperature was higher at the top of the plant than at the bottom. Over time, the leaf temperature measured around 11-13 AM changed from 26.55→23.21→22.80→26.67℃ in the lower part (pL), and from 26.52→24.48→24.55→27.78℃ in the upper part (pAs). And VPD changed from 1.45→0.94→0.74→1.46kPa in pL and from 1.11→0.86→0.71→1.28kPa in pAs. Accordingly, the transpiration rate changed from 4.25→0.17→4.08→0.52mmol·m-2·s-1 in pL, 7.61→2.45→1.94→4.39→0.52mmol·m-2·s-1 in pAs, and from pAs to pL. It was significantly higher than The difference between the lower and upper parts (pL-pAs) was higher in pAs than pL in leaf temperature, light intensity, and transpiration rate, but the water vapor pressure difference was higher in pL. In this way, paprika shows differences in the environment and photosynthetic factors between the upper and lower parts during the cultivation period, so it is judged that this needs to be taken into consideration in future research.

Deletion Timing of Cic Alleles during Hematopoiesis Determines the Degree of Peripheral CD4+ T Cell Activation and Proliferation

  • Guk-Yeol Park;Gil-Woo Lee;Soeun Kim;Hyebeen Hong;Jong Seok Park;Jae-Ho Cho;Yoontae Lee
    • IMMUNE NETWORK
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    • v.20 no.5
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    • pp.43.1-43.11
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    • 2020
  • Capicua (CIC) is a transcriptional repressor that regulates several developmental processes. CIC deficiency results in lymphoproliferative autoimmunity accompanied by expansion of CD44hiCD62Llo effector/memory and follicular Th cell populations. Deletion of Cic alleles in hematopoietic stem cells (Vav1-Cre-mediated knockout of Cic) causes more severe autoimmunity than that caused by the knockout of Cic in CD4+CD8+ double positive thymocytes (Cd4-Cre-mediated knockout of Cic). In this study, we compared splenic CD4+ T cell activation and proliferation between whole immune cell-specific Cic-null (Cicf/f;Vav1-Cre) and T cell-specific Cic-null (Cicf/f;Cd4-Cre) mice. Hyperactivation and hyperproliferation of CD4+ T cells were more apparent in Cicf/f;Vav1-Cre mice than in Cicf/f;Cd4-Cre mice. Cicf/f;Vav1-Cre CD4+ T cells more rapidly proliferated and secreted larger amounts of IL-2 upon TCR stimulation than did Cicf/f;Cd4-Cre CD4+ T cells, while the TCR stimulation-induced activation of the TCR signaling cascade and calcium flux were comparable between them. Mixed wild-type and Cicf/f;Vav1-Cre bone marrow chimeras also exhibited more apparent hyperactivation and hyperproliferation of Cic-deficient CD4+ T cells than did mixed wild-type and Cicf/f;Cd4-Cre bone marrow chimeras. Taken together, our data demonstrate that CIC deficiency at the beginning of T cell development endows peripheral CD4+ T cells with enhanced T cell activation and proliferative capability.

Effect of Long Term Waterlogging on the Growth and Nutrient Contents of 'Campbell Early' and 'Kyoho' Grapevine Cultivars (장기 침수가 포도 '캠벨얼리'와 '거봉' 품종의 생육과 양분함량에 미치는 영향)

  • Kang, Seok-Beom;Lee, In-Bog;Jang, Han-Ik;Park, Jin-Myeon;Moon, Doo-Khil
    • Korean Journal of Environmental Agriculture
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    • v.27 no.2
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    • pp.178-184
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    • 2008
  • This work was carried out to investigate the effect of waterlogging on the growth and nutrient contents of 'Campbell Early' and 'Kyoho' grapevines under the vinyl house condition from June 14 to July 20, 2005. For the trial, seedlings of two-year-old grapevine were transplanted to 40 L pot with a sandy loam soil. Irrigation point of non-waterlogging(control) treatment was controlled at -40 kPa of soil water tension using tensiometer and waterlogging treatments were imposed for 35 days at the water levels of above 10 cm from the soil surface using tap water. The growth of aerial(shoot length, leaf number and stem diameter) and underground(root) parts of 'Campbell Early' and 'Kyoho' grapevines tended to be wholly reduced by waterlogging, while the growth of aerial parts were more severely impaired in 'Kyoho' than in 'Campbell Early' cultivar. The different responses for waterlogging between two grapevines seem to be related with the capacity for absorbing mineral nutrients, because nitrogen content of 'Campbell Early' cultivar leaves was significantly higher than that of 'Kyoho' cultivar although the contents of phosphorus and potassium in leaves of two grapevine cultivars were similarly declined. There was no significant different of fruit quality, such as contents of soluble solid, titratable acidity and weight of berry in 'Campbell Early' between waterlogging and control. In 'Kyoho' cultivar, however, berry weight and titratable acidity were decreased and soluble solid content was increased by waterlogging. It was assumed that waterlogging stress for grapevines promotes maturation and coloring processes of berries by stimulating maturation hormone such as ethylene. In conclusion, 'Campbell Early' cultivar seems to be more tolerable than 'Kyoho' cultivar when comparing the growth responses and nutrient contents between two grapevine cultivars under waterlogging.

Effect of Liquid Pig Manure and Synthetic Fertilizer on Rice Growth, Yield, and Quality (벼 생육, 수량과 품질에 대한 돈분액비와 화학비료 시용 효과)

  • Kwon, Young-Rip;Kim, Ju;Ahn, Byung-Koo;Lee, Sang-Bok
    • Korean Journal of Environmental Agriculture
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    • v.29 no.1
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    • pp.54-60
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    • 2010
  • We have researched the changes in nutrient content in each phase of fermentation in crops treated with liquefied pig fertilizer, and have determined the best method for applying livestock excrement to cultured crops. In the execution of this experiment, rice was cultivated to full maturity at a paddy field in Jeollabuk-Do Agriculture Research and Extension Services(Jeon-buk series) from 2007 to 2008. The rice plant nitrogen absorption quantity change, according to the growth stages of the cultivated rice, was 20.3% in the rice treated with the liquid pig manure and 22.2% the chemical fertilizer at highest congelation. The chemical fertilizer showed a higher absorption quantity than the liquid manure compost. The nitrogen density at highest congelation was 1.5% in the chemical fertilizer, and 1.8% in the pig manure liquid compost not a significant difference. The stem height at harvest time was 73.8 cm in the crops treated with the liquid pig manure compost. Those treated with the chemical fertilizer, yielded a height of 4.2 cm less than the crops treated with the liquid pig manure compost. The yield was 507 kg/10a in the liquid pig manure compost treated rice, compared with the chemical fertilizer, which showed a value of 1.2% lower. The protein content was 6.3% in the rice treated with the chemical fertilizer, but 6.4% in the rice treated with the liquid pig manure compost. This is not a significant difference. However, the lodging rice plant treated with the chemical fertilizer control showed a protein content of 6.8%, which was even higher than the normal rice. The head rice ratio in the brown rice and the polished rice ended up to be lower in the crop treated with the liquid pig manure than that treated with the chemical fertilizer, Quality, the palatability value, was similar in both groups. The above result indicate that, the effect of liquid pig manure compost corresponds to the effect of chemical fertilizer, when each are scattered uniformly.

Characteristics of Seedling Quality of Daphniphyllum macropodum 2-year-old Container Seedlings by Shading Level (굴거리나무 2년생 용기묘의 피음수준별 묘목품질 특성)

  • Song, Ki Seon;Choi, Kyu Seong;Sung, Hwan In;Jeon, Kwon Seok;An, Kyoung Jin;Kim, Jong Jin
    • Journal of Korean Society of Forest Science
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    • v.104 no.3
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    • pp.390-396
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    • 2015
  • This study was carried out in order to closely examine quality index by shading level of 2-year-old (1-1 seedling) container seedling of Daphniphyllum macropodum which is known as the species of having shade tolerance that is evergreen broad leaved tree in the warm temperate region. The shading treatment was regulated with the shading level of full sunlight, and 35%, 55%, 75%, 95% of full sunlight. As a result of surveying growth according to the shading level, both height and root collar diameter were surveyed to be the highest with 45.1 cm and 8.22 mm, respectively, under 75% of shading. The next was surveyed to be 43.2 cm & 8.05 mm and 42.5 cm & 7.98 mm, respectively, in order of 35% and 55% in shading. Leaf, shoot, root, and whole dry mass production were the highest under 75% of shading. The next was higher in leaf, stem, and whole dry mass production under 55% of shading. A root was higher under 35% of shading in the next. H/D ratio was the range of 5.29~5.35 under the 35~75% shading that showed the relatively high height and root collar diameter. T/R ratio was the lowest with 1.17 under 35% of shading. It was 0.41 under 95% of shading as for LWR, 0.24 under 75%-95% of shading as for SWR, and 0.46 under full sun and 35% shading as for RWR. QI was the highest with 3.74 under 75% of shading. As a result of surveying the whole experiment, it is concluded that the production of D. macropodum seedling is more effective under 75% shading

The Production of Adventitious Sprouts by Water-soak and Vegetative Propagation of Plus tree of Ash Species Through Cuttings of Their Sprouts (물푸레나무속(屬) 수형목(秀型木)의 수심(水沈)에 의(依)한 지조맹아(枝條萌芽) 발생력(發生力)과 이를 이용(利用)한 녹지삽목(綠枝揷木) 증식시험(增殖試驗))

  • Han, Sang Don;Hong, Sung Ho;Min, Young Taek;Kim, Young Mo;Kim, Hong Eun
    • Journal of Korean Society of Forest Science
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    • v.83 no.2
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    • pp.148-154
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    • 1994
  • As a vegetative propagation method for ash species, which is a dioecism and a long cycle of fructification, cut-stem was soaked in water to induce adventitious sprouts, and 2-year-old ash seedling was cut in a nursery to induce adventitious sprouts. We obtained the 1,019 adventitious sprouts from branches of 101 plus trees througout the country. The mean ortet-age is 48. There is not a correlation between ortet ages and production of adventitious sprouts. These sprouts were placed in a cutting bed for rooting. Root ability varied with environmental factors of cuttings. The best rooting(87%) resulted from cutting performed in a vinyl-plastic greenhouse. Rooting was better on perlite+peat moss(2 : 1) medium than other media tested. The rooting ability was generally higher in 2-year-old ortet than plus tree ortet. In the root development of cuttings the non-container cuttings was better than container cuttings.

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Effects of Elevated Atmospheric CO2 and Nitrogen Fertilization on Growth and Carbon Uptake of Yellow Poplar Seedlings (대기 이산화탄소 증가와 질소 시비가 백합나무 유묘의 생장과 탄소 흡수에 미치는 영향)

  • Chung, Mi-Sook;Han, Sim-Hee;Kim, Du-Hyun;Lee, Jae-Cheon;Kim, Pan-Gi
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.14 no.3
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    • pp.108-118
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    • 2012
  • To investigate the responses of yellow poplar (Liriodendron tulipifera L.) seedlings to the interactive effects of the elevated atmospheric $CO_2$ level and nitrogen addition, we measured biomass, photosynthetic pigments, photosynthesis, and the contents of nitrogen (N) and carbon (C) from the seedlings after 16 weeks of the treatments. Yellow poplar seedlings were grown under the ambient ($400{\mu}mol\;mol^{-1}$) and the elevated (560 and $720{\mu}mol\;mol^{-1}$) CO2 concentratoins with three different N addition levels (1.2, 2.4, and $3.6g\;kg^{-1}$) in the Open Top Chambers (OTC). The dry weight of the seedlings enhanced with the increased N levels under the elevated $CO_2$ concentrations and the increment of the dry weight differed among the different N levels. Photosynthetic pigment content of the yellow poplar leaves also increased with the increase of the $CO_2$ concentration levels. The effects of the N levels on the photosynthetic pigment content, however, were significantly different among the $CO_2$ levels. Photosynthetic rates were affected by the levels of $CO_2$ and N concentrations. Stomatal conductance and transpiration rates increased with increasing $CO_2$ concentration. The carboxylation efficiency of the seedlings without N addition increased under the higher $CO_2$ concentrations whereas that with N addition decreased under the elevated $CO_2$ concentrations. Nitrogen and carbon uptake in leaf, stem, and root increased with the elevated $CO_2$ concentration level and N addition. In conclusion, under the elevated $CO_2$ concentrations, physiological characteristics and carbon uptake of the yellow poplar seedling were improved and increased with N addition.