• Nuclear Engineering and Technology
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• v.51 no.3
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• pp.792-799
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• 2019

The present study aims to investigate the fluorination of thorium oxide ($ThO_2$) by ammonium hydrogen difluoride ($NH_4HF_2$). Fluorination was performed at room temperature by mixing $ThO_2$ and $NH_4HF_2$ at different molar ratios, which was then left to react for 20 days. Next, the mixtures were analyzed using X-ray diffraction (XRD) at the intervals of 5, 10, 15, and 20 days, followed by the heating of the mixtures at $450-750^{\circ}C$ with argon gas flow. The characterization of $ThF_4$ was established using X-ray diffraction (XRD) and scanning electron microscopy-dispersion X-ray spectroscopy (SEM-EDX). In this study, ammonium thorium fluoride was synthesized through the fluorination of $ThO_2$ at room temperature. The optimum molar ratio in synthesizing ammonium thorium fluoride was 1.0:5.5 ($ThO_2:NH_4HF_2$) with 5 days reaction time. In addition, the heating of ammonium thorium fluoride at $450^{\circ}C$ was sufficient to produce $ThF_4$. Overall, this study proved that $NH_4HF_2$ is one of the fluorination agents that is capable of synthesizing $ThF_4$.

• Lettere Italiane
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• no.33
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• pp.1-27
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• 2011

Questo studio ha lo scopo di configurare la gerarchia tematica del sintagma genitivale in italiano all'interno della struttura sintattica. Il sintagma genitivale composto dalla forma "sostantivo+di+sostantivo", può avere i significati di descrizione, origine, apposizione, parte, luogo, e anche può rappresentare la struttura argomentale come argomento esterno(caso soggettivo) o argomento interno(caso oggettivo) e può assegnare il ruolo tematico di agente, tema, esperiente, beneficario in relazione al rapporto con la testa nominale oltre ad avere il significato possesivo. Per quanto riguarda la realizzazione e il significato dell'argomento nel sintagma genitivale diverse che cambiano secondo il tipo della testa nominale, ho classificato i nomi deverbali come nomi monoargomentali, nomi biargomentali, nomi triargomentali sulla base di Renzi et al(1991). Inoltre avendo confermato che il marcatore del caso genitivale di deve esserci nel caso in cui obbligatoriamente la struttura del sintagma nominale composto dai vari livelli, come NP, FP e DP, proposti da Longobardi(2001) per spiegare la differenza semantica del sintagma genitivale con la struttura sintattica, ho cercato di individuare l'ordine degli argomenti, osservando l'ambiguità e il cambiamento del significato del sintagma genitivale nel sintagma nominale. Cioé la differenza della possibilità interpretativa è una cosa strutturale, quindi possibilmente si può configurare la semantica del sintagma genitivale nella struttura sintattica.

• Journal of Navigation and Port Research
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• v.42 no.3
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• pp.217-226
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• 2018

International major container terminals are trying to expand automation facilities in order to dominate the competition and grow as central harbors. Recently, system design and development were put underway to fully integrate automation systems in container terminals. This is because it can focus on improving the efficiency of the yard operations in container terminals and facilitates integration with other container terminal operation processes. Automation in the container terminal business today is essential to better serve customers and improve profitability. Real-time position and status of container handling equipment (CHE) have been required for more efficient terminal operations and consequently higher productivity. This study examined the real-time location and status of the container terminal automation equipment using DGPS in container terminals, and reviewed the components and functions of the container terminal automation yard equipment systems that developed, applied, and operated the automation systems. In addition, this study compared the existing yard system and the automation yard system and presented application methods. Also, the results revealed that the productivity of the container terminal and the efficiency of the transportation equipment can be further increased when the optimal yard automation transportation equipment system is used to efficiently operate the transportation equipment, which is the core equipment of the container terminal.

• Research in Community and Public Health Nursing
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• v.11 no.2
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• pp.423-440
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• 2000

This research was conducted to identify the following: the home care needs of patients with dementia and the burden on the primary family care giver: to provide basic data required to develop nursing intervention for the care giver: and to suggest recommendations for medical institutions and social services that could reduce the burden on the families of people suffering from dementia. subjects of this research were 53 patients of the two Public Health Centers of Cheju Province who are suffering from dementia and their families. The instrument used in the research was Kuen. Jung Don (1994)' s assessment tool of burden in the primary family care giver who has parents with senile dementia and Yoo. Young Mi(1998)'s assessment tool of home care need. modified by the researcher in the questionnaire by a Likert rating scale. The period of data collection was from February 8. 2000 to March 10. 2000. Collected data was analyzed by SPSS, using mean, standard deviation. ANOVA, t-test and Pearson correlation coefficient. The result of this research was that there was not a significant correlation between the burden on the care giver and the level of dementia, its duration, the patient's ability to perform daily tasks, the period of care giving. and the use of social services, although the lower the patient's ability to perform daily tasks. and the worse the care giver's own health situation, the higher the burden on the primary family care giver. The following suggestions are made based on the results of this research. 1. More than half of the subjects don't use social facilities and services. More publicity and referral efforts are needed about medical institutions. nursing institutions and other facilities that specialize in services for dementia sufferers and their families. 2. Nursing services should include intensive education for the primary care giver in the most important aspects of home care. 3. Further research should be done, and should include data from all parts of Cheju Province.

• Journal of Life Science
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• v.31 no.11
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• pp.980-986
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• 2021

Natural products have always been an attractive source in terms of novel anti-metastatic compounds which can hinder MMP expression and activity. Corydalis heterocarpa is a salt marsh plant found in the seashores throughout Korea. Its yellow flowers and spikes have been an ingredient in folk medicine to treat spasm and contractions. The present study assessed the potential of different solvent-based fractions from the crude extract of Corydalis heterocarpa (CHE), a halophyte with reported bioactivities, to suppress the PMA-induced MMP expression in human fibrosarcoma HT-1080 cells. The solvent fractions which were named after the solvent used for fractionation (n-hexane, 85% aqueous (aq.) methanol (MeOH), n-butanol (BuOH), and H₂O were shown to inhibit the both elevated mRNA and protein expression levels of MMP-2 and MMP-9 and simultaneously relieved the suppression on the expression of the endogenous MMP inhibitors TIMP-1 and TIMP-2. Results indicated that the CHE fractions might intervene with the PMA-induced activation of the MAPK signaling which is the upstream activator of MMP overexpression. Among tested samples, 85% aq. MeOH and n-hexane fractions of CHE was determined to be the most active and future studies to isolate the bioactive substances responsible for the regulation of the MMP expression are, therefore, urged. In conclusion, C. heterocarpa was shown to be a potential source of anti-metastatic compounds and n-Hexane and MeOH fractions might yield lead molecules to develop novel MMP inhibitors.

• Health Policy and Management
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• v.33 no.3
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• pp.243-252
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• 2023

This paper aims to introduce Korea's total current health expenditure (CHE) and National Health Accounts of the year 2021 and their 2022 preliminary figures constructed on the basis of the System of Health Accounts 2011. As CHE includes expenditures for prevention, tracking, and treatment of coronavirus disease 2019 (COVID-19) and compensation for losses to medical institutions from 2020, the details are also introduced. Korea's total CHE in 2021 is 193.3 trillion won, which is 9.3% of gross domestic product (GDP). The preliminary figure in 2022, 209.0 trillion won, exceeded the 200 trillion won line for the first time, and its "ratio to GDP" of 9.7% is expected to exceed the average of Organisation for Economic Co-Operation and Development member countries for the first time. Korea's health expenditures, which were well controlled until the end of the 20th century, have increased at an alarming rate since the beginning of the 21st century, threatening the sustainability of national health insurance. The increase in health expenditure after 2020 is partly due to a temporary increase in response to COVID-19. However, when considering the structure of Korea's health insurance price hike, where the ratchet effect of increased medical expenses works particularly strongly, it is unlikely that the accelerating growth trend that has lasted for more than 20 years will stop easily. More aggressive policies to control medical expenses are required in the national health insurance which not only constitutes the main financing sources of the Korean health system but also has the most powerful policy means in effect for changes in the health care provision.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.178.2-178.2
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• 2007

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.137-140
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• 2000

We provide an useful method to design codebooks with better performance than conventional methods. In the proposed method, new codevectors obtained by learning iterations are not the centroid vectors which is the representatives of partitions, but the vectors manipulated by the distance between new codevectors and old codevectors in the early stages of learning iteration. Experimental results show that the codevectors in the obtained by the proposed method converge to a better locally optimal codebook.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.183-187
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• 2004

The most significant degradation problem of PLED has been described and new buffer layer material aimed for use as HTL in PLED to solve this issue has been studied. This approach has enabled the increase of the green device efficiency (${\sim}$2x) and lifetime (${\sim}$5-6x).

• IE interfaces
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• v.15 no.3
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• pp.286-296
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• 2002

Products which are sold with warranty, preventive maintenance actions by manufacturers and/or buyers have an impact on the total costs for both parties. In this paper, we develop the models to study the expected warranty cost for products with free repairable warranty with three types of discrete preventive maintenance. We deal with by utilizing the concept that preventive maintenance reduces the virtual age of the system. We assume that the maintenance planning horizon can be segmented into k discrete and equally sized periods. In such a scenario, numerical examples are presented.