• International Journal of Computer Science & Network Security
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• 제22권3호
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• pp.77-88
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• 2022

In response to the significant COVID-19 outbreak, countries have enforced the use of E-learning systems as an alternative to traditional learning; to contain the virus and minimize the infection rate while maintaining the continuity of the learning experience. However, the effective adoption of E-learning systems requires a well-understanding of critical factors, especially in times of crisis. In this regard, this study intends to assess the success of the E-learning system adoption by Higher Education Institutions (HEIs) during the crisis of COVID-19 by utilizing the Information Systems Success (ISS) model. This study's adopted model consists of nine interdependent dimensions, namely: Technical System Quality, Information Quality, Service Quality, Learner Quality, Perceived Satisfaction, Perceived Usefulness, System Use, Intention to Use, and System Success. An electronic survey was distributed among higher education students from different universities in Saudi Arabia to explore each model's dimension. Structural Equation Modeling (SEM) has been applied via SmartPLS software to test the causal relationships between dimensions. This study's main results revealed that students' Service Quality, Learner Quality, and the Intention to Use by students are essential drives for E-learning System Use during the Covid-19 pandemic. Meanwhile, the Intention to Use the system is significantly influenced by Perceived Satisfaction and Perceived Usefulness dimensions. Further, Perceived Satisfaction, Perceived Usefulness, and System Use are interdependent, and all three have a significant positive impact on E-learning System Success.

• 항공우주시스템공학회지
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• 제16권5호
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• pp.26-34
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• 2022

정지궤도위성의 추진시스템은 전이궤도에서 궤도상승, 정상 운영모드에서 남/북방향, 동/서방향 궤도위치유지 및 모멘텀 덤핑을 위해 일반적으로 사용된다. 최근 정지궤도위성에 완전 전기추진시스템을 적용할 경우 화학추진시스템 보다 탑재체의 탑재용량이 약 40% 증가 할 수 있어 정지궤도 위성에 전기추진시스템의 활용이 점차 증가 되고 있다. 그러나 이러한 장점에도 불구하고 전기추진시스템의 사용이 모든 정지궤도위성에 적용하기에는 여러 제약 조건이 있어 위성 임무에 따라 이에 적합한 추진시스템을 적용하여 왔다. 본 연구에서는 완전 전기추진시스템 적용한 국내 정지궤도위성 개발 시 고려되어야 할 정지궤도위성의 운영제약조건 분석, 전기추력기에 의한 오염영향, 방사선 노출에 따른 부품배치 고려 및 제어메카니즘 설계, 전기추력기용 고전압 제어유닛의 부동접지 설계방안들이 분석되었다.

• BMB Reports
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• 제56권3호
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• pp.153-159
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• 2023

Neuronal differentiation is highly coordinated through a cascade of gene expression, mediated via interactions between trans-acting transcription factors and cis-regulatory elements of their target genes. However, the mechanisms of transcriptional regulation that determine neuronal cell-fate are not fully understood. Here, we show that the nuclear transcription factor Y (NF-Y) subunit, NFYA-1, is necessary and sufficient to express the flp-3 neuropeptide gene in the IL1 neurons of C. elegans. flp-3 expression is decreased in dorsal and lateral, but not ventral IL1s of nfya-1 mutants. The expression of another terminally differentiated gene, eat-4 vesicular glutamate transporter, is abolished, whereas the unc-8 DEG/ENaC gene and pan-neuronal genes are expressed normally in IL1s of nfya-1 mutants. nfya-1 is expressed in and acts in IL1s to regulate flp-3 and eat-4 expression. Ectopic expression of NFYA-1 drives the expression of flp-3 gene in other cell-types. Promoter analysis of IL1-expressed genes results in the identification of several cis-regulatory motifs which are necessary for IL1 expression, including a putative CCAAT-box located in the flp-3 promoter that NFYA-1 directly interacts with. NFYA-1 and NFYA-2, together with NFYB-1 and NFYC-1, exhibit partly or fully redundant roles in the regulation of flp-3 or unc-8 expression, respectively. Taken together, our data indicate that the NF-Y complex regulates neuronal subtype-specification via regulating a set of terminal-differentiation genes.

• The Korean Journal of Physiology and Pharmacology
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• 제27권3호
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• pp.197-208
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• 2023

Dysregulation of certain long non-coding RNAs may facilitate tumor initiation and progression. However, numerous carcinogenesis-related long noncoding RNAs have not been characterized. The goal of this study was to elucidate the role of LINC00562 in gastric cancer (GC). The expression of LINC00562 was analyzed using real-time quantitative PCR and Western blotting. The proliferative capacity of GC cells was determined using Cell Counting Kit-8 and colony-formation assays. The migration of GC cells were evaluated using wound-healing assays. The apoptosis of GC cells was assessed by measuring the expression levels of apoptosis-related proteins (Bax and Bcl-2). Xenograft models in nude mice were constructed for in vivo functional analysis of LINC00562. The binding relationship between miR-4636 and LINC00562 or adaptor protein complex 1 sigma 3 (AP1S3), obtained from public databases, was confirmed using dual-luciferase and RNA-binding protein immunoprecipitation experiments. LINC00562 was expressed in GC cells at high levels. Knockdown of LINC00562 repressed GC cell growth and migration, promoted apoptosis in vitro, and inhibited tumor growth in nude mouse models. LINC00562 directly targeted miR-4636, and miR-4636 depletion restored the GC cell behavior inhibited by LINC00562 absence. AP1S3, an oncogene, binds to miR-4636. MiR-4636 downregulation increased AP1S3 level, restoring GC cell malignant behaviors inhibited by AP1S3 downregulation. Thus, LINC00562 exerts carcinogenic effects on GC development by targeting miR-4636-mediated AP1S3 signaling.

• Journal of Korea Trade
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• 제26권7호
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• pp.77-92
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• 2022

Purpose - This paper is an empirical investigation of the mediation effect of innovation activity in industry transformation considering the relationship between the semiconductor industry and high-quality economic development. The research questions are whether the semiconductor industry drives high-quality economic development and if so, what is the semiconductor industry's role in high-quality development? We found that the semiconductor industry has clearly improved the quality of economic development, and its comparative advantage has significantly increased per capita national incomes. Furthermore, innovation activity proved to be an intermediary factor for the semiconductor industry to promote high-quality economic development. The world economy should aim to reasonably develop the international semiconductor industry and cultivate innovation markets. Design/methodology - Our empirical model considers the relationship between the semiconductor industry, innovation activity, and high-quality economic development. We constructed an analysis framework based on data from 199 World Bank economies between 1995 and 2019, and we used a mediation effect method to calculate the total effect of the semiconductor industry on promoting high-quality economic development, the indirect effect of the semiconductor industry on promoting innovation activity, and the mediation effect of these innovation activities on the promotion of high-quality economic development. Findings - The results show that the semiconductor industry has significantly promoted high-quality economic development. This is true even after the robustness test of grouping and alternative variables was applied. An analysis of the mechanism shows that promoting patents, scientific research, efficient government, and urban management innovation are important mechanisms for the semiconductor industry to release high-quality development dividends. Originality/value - Although it has been shown that specific industries like semiconductors can affect high-quality economic development through industrial upgrading, few researchers have attempted to empirically test the impact of the semiconductor industry on high-quality economic development. In this paper, we use a mediation effect model, alternative variables and a grouping test to find the internal mechanisms of the comparative advantage of the semiconductor industry in high-quality economic development from the perspective of innovation activity.

• Journal of Information Science Theory and Practice
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• 제10권spc호
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• pp.56-65
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• 2022

Korea Institute of Science and Technology Information (KISTI) is a Worldwide LHC Computing Grid (WLCG) Tier-1 center mandated to preserve raw data produced from A Large Ion Collider Experiment (ALICE) experiment using the world's largest particle accelerator, the Large Hadron Collider (LHC) at European Organization for Nuclear Research (CERN). Physical medium used widely for long-term data preservation is tape, thanks to its reliability and least price per capacity compared to other media such as optical disk, hard disk, and solid-state disk. However, decreasing numbers of manufacturers for both tape drives and cartridges, and patent disputes among them escalated risk of market. As alternative to tape-based data preservation strategy, we proposed disk-only erasure-coded archival storage system, Custodial Disk Storage (CDS), powered by Exascale Open Storage (EOS), an open-source storage management software developed by CERN. CDS system consists of 18 high density Just-Bunch-Of-Disks (JBOD) enclosures attached to 9 servers through 12 Gbps Serial Attached SCSI (SAS) Host Bus Adapter (HBA) interfaces via multiple paths for redundancy and multiplexing. For data protection, we introduced Reed-Solomon (RS) (16, 4) Erasure Coding (EC) layout, where the number of data and parity blocks are 12 and 4 respectively, which gives the annual data loss probability equivalent to 5×10^-14. In this paper, we discuss CDS system design based on JBOD products, performance limitations, and data protection strategy accommodating EOS EC implementation. We present CDS operations for ALICE experiment and long-term power consumption measurement.

• Journal of Information Science Theory and Practice
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• 제10권spc호
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• pp.66-75
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• 2022

The manufacturing industry is the foundation that drives economic growth, and manufacturing innovation is essential for sustainable growth advantage and the transition into a digital economy. Therefore, major countries actively support the field of simulations, which incorporate information and communication technologies into manufacturing, and announce various policies at the national level along with increasing investment. Simulation technology virtualizes product development processes to replace physical production and experimentation of products, dramatically reducing time and costs. In South Korea, the Korea Institute of Science and Technology Information (KISTI) has supported manufacturing companies for about 14 years by providing relevant technologies. This study uses the input-output table for the Bank of Korea to analyze the economic ripple effect. First, we identified the domestic industrial sector dealing with the supercomputing-based simulation industry. Then we analyzed its ripple effects by dividing them into the production inducement effect, value-added inducement effect, employment inducement effect, and forward/backward linkage effect. Consequently, when the supercomputing simulation budget of KISTI (28.3 billion won, 2007-2020) was set as an input coefficient, the analysis showed 45.1 billion won as the production inducement effect, 24.7 billion won as the value-added inducement effect, and 282 individuals per 1 billion won as the employment inducement effect. This study is significant in that it derived the effects of the inputs by analyzing the economic ripple effects of the projects of KISTI, which have been supporting South Korean manufacturing companies for the past 14 years with supercomputing-based simulations.

• ALGAE
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• 제37권4호
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• pp.331-347
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• 2022

Atopic dermatitis (AD) is one of major skin inflammatory diseases characterized by excessive Th2-mediated immune responses. Recent evidence provides that interlukin-13 (IL-13) plays the role of a key Th2 cytokine that drives the inflammation underlining AD. Due to adverse effects of commercially available synthetic drugs, the need for treatments based on natural products is gaining much attention. Sargassum horneri is an edible brown algae known for beneficial bioactivities including anti-inflammation. We investigated if polyphenol-rich S. horneri extracts (SHE) could suppress AD-like skin lesions in NC/Nga mice and if that involved inhibition of the infiltration of Th2-mediated cytokine IL-13. We observed markedly increased infiltration of IL-13 positive cells in AD-like skin lesions of mice but SHE treatments decreased it. Also, the dermal expression of IL-13 was sufficient to cause inflammatory responses in mice skin resembling human AD. SHE suppressed the dermal infiltration of inflammatory cells where IL-13 plays a crucial role in skin tissues and in the recruitment of inflammatory cells. Furthermore, it was confirmed that SHE reduced T cell, dendritic cell, and macrophage populations in spleen. Moreover, SHE decreased the collagen deposition in skin and ear dermis resulting in reduced fibrosis that occurs in AD due to excessive collagen. Taken together, our results reveal that SHE suppressed the infiltration of inflammatory cells into skin dermis by decreasing the infiltration of IL-13 positive cells. Therefore, SHE could be taken as a useful therapeutic agent to alleviate AD.

• Korean Chemical Engineering Research
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• 제61권4호
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• pp.505-516
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• 2023

플라스틱은 가공과 처리가 간단하여 매년 생산량이 증가하고 있으며 이에 따라 플라스틱 폐기물의 양 또한 매년 증가하고 있다. 플라스틱 폐기물 문제를 해결하기 위하여 촉매를 활용한 업사이클링 공정은 유망한 해결책으로 제시되고 있다. 다양한 금속(Ru, Pt 등) 및 지지체(TiO₂, CeO₂ 등)가 폴리 올레핀계 플라스틱의 화학적 재활용에 적용되었다. 입자 크기를 조절하고, 지지체의 특성 및 이종 금속을 도입하여 액체 연료의 선택도를 향상시키고 메탄 생성 양을 줄이려는 시도가 있었다. 한편으로는 값비싼 귀금속의 양을 줄임으로써 최적의 촉매를 찾기 위한 연구를 진행하였다. 본 논문에서는 이러한 hydrogenolysis 반응 및 hydrocracking 반응에서 경제성을 높이기 위하여 어떠한 시도들이 있었는지 살펴보고자 한다. 이러한 관점에서 촉매 업사이클링 공정을 통해 플라스틱 폐기물 문제를 해결할 가능성을 제시하고자 한다.

• Clinical and Experimental Vaccine Research
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• 제12권3호
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• pp.209-215
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• 2023

Purpose: The delay in acceptance or refusal to get vaccinated despite the availability of services is called vaccine hesitancy. The Global Polio Eradication Initiative in Pakistan faced consistent barriers preventing the eradication of the disease in the country. Similarly with the advent of the coronavirus disease 2019 (COVID-19) pandemic mass vaccination drives were initiated to a vaccine hesitant population. The aim of this study is to explore the prevalence and reasons for COVID-19 vaccine hesitancy in the Pakistani population. Materials and Methods: Cross-sectional study conducted during July to September 2021 using a snowball sampling technique targeting the adult population of Pakistan. The modified version of the vaccine hesitancy questionnaire related to the Strategic Advisory Group of Experts on Immunization Vaccine Hesitancy matrix was distributed online. Results: Out of 973 participants, 52.4% were immediately willing to take the vaccine and constituted the acceptance group whereas the remaining 47.6% who were still not sure formed the hesitant group. Support from leaders was found to be statistically significant for the difference between the hesitant and acceptance groups (p-value=0.027). Hesitant people were concerned about the effectiveness of the vaccine (60.9%) and potential side effects (57.9%) as it was not sufficiently tested prior to launch (44.7%). Age and education were significant factors affecting the acceptance of vaccination. The most trusted source of information regarding vaccination was health care workers (43.8%). Conclusion: A moderately high prevalence of vaccine hesitancy was reported in Pakistan. To overcome it, policymakers need to address the reasons for it. Leaders, celebrities, and healthcare workers can play an instrumental role in dispelling conspiracy theories regarding vaccines and making the vaccination drive a success.