• Journal of the Korean Mathematical Society
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• 제59권6호
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• pp.1171-1184
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• 2022

We study the real-analytic continuation of local real-analytic solutions to the Cauchy problems of quasi-linear partial differential equations of first order for a scalar function. By making use of the first integrals of the characteristic vector field and the implicit function theorem we determine the maximal domain of the analytic extension of a local solution as a single-valued function. We present some examples including the scalar conservation laws that admit global first integrals so that our method is applicable.

• Animal Systematics, Evolution and Diversity
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• 제22권2호
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• pp.189-194
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• 2006

First zoeas of Alpheus albatrossae (Banner, 1953) are described and illustrated for the first time, based on laboratory-hatched zoeas from a female collected in Ulleung-do Island, eastern Korea. The first zoeas of A. albatrossae can be distinguished from those of seven known species of Alpheus (A. brevicristatus, A. digitalis, A. heeia, A. japonicus, A. lobidens, A. richardsoni, and A. sudara) from Korea by having 6-segmented scale of the antenna and the endopod of the first maxilliped with four terminal setae.

• Journal of Korean Institute of Fire Science & Engineering
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• 제1권2호
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• pp.28-41
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• 2000

Since a few years ago, great disasters have often took place in domestic and abroad, such as Sampoong Department store collapse, Sea-land disaster accident, Incheon Hof fire accidents. Whenever a lot of accidents occurred such as fire, gas explosion, traffic accident, mountain accident, various disease, people required 119 first aid service. As the result, even for the last year, average 2,608 person per day were temporary treated and carried to near hospital by 119 system. But first-aid team or first grade EMT(emergency medical technician) that should provide high quality service and save important lives, might have negatively treated or made their duty only for simple transfer, when they were imminent of emergency case in every kinds of accident spot. Because they worried about medical dispute for "task restriction for EMT" decided by medical laws or rules of first aid. So it was proposed that "task restriction for EMT" should be mitigated or released in the possible range on this occasion.

• Structural Engineering and Mechanics
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• 제28권5호
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• pp.515-524
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• 2008

In this paper the effect of prestressing force on the first flexural natural frequency of beams is studied. Finite element technique is used to model the beam-tendon system, and the prestressing force is applied in the form of initial tension in the tendon. It is shown that the effect of prestressing force on the first natural frequency depends on bonded and unbonded nature of the tendon, and also on the eccentricity of tendon. For the beams with bonded tendon, the prestressing force does not have any appreciable effect on the first flexural natural frequency. However, for the beams with unbonded tendon, the first natural frequency significantly changes with the prestressing force and eccentricity of the tendon. If the eccentricity of tendon is small, then the first natural frequency decreases with the prestressing force and if the eccentricity is large, then the first flexural natural frequency increases with the prestressing force. Results of the present study clearly indicate that the first natural frequency can not be used as an easy indicator for detecting the loss of prestressing force, as has been attempted in some of the past studies.

• Korean Journal of Child Studies
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• 제13권1호
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• pp.125-138
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• 1992

The purpose of the present study was to examine the development of embedding through relative clause formation in the first language acquisition of Korean. Results are reported from the study of the spantaneous natural speech of 36 young Korean children ranging from 16 months to 45 months in age acquiring Korean as their first language in Chinju, Korea. The results revealed a developmental order in the first language acquisition of Korean relative clause structures. Namely, a free or headless relative clause appears to be acquired first, before lexically headed restrictive relative construction. This order is consistent with one evidenced in English (and also Chinese) first language acquisition, 'free' relatives appear to provide a developmentally early stage in the acquisition of restrictive relative clauses. The Korean data provided additional evidence for an intermediary stage with an overt complementizer as well as an overt lexical head. Implications for the results are disscused with regard to a continuous theory of universal grammar in the first language acquisition.

• Journal of the Korean Society of Industry Convergence
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• 제27권2_1호
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• pp.287-295
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• 2024

Many first aiders suffer from the stress of working in uncertain disaster sites. The stress of responding to disasters leads to an increase in post-traumatic stress disorder (PTSD) and a decrease in psychological well-being. It also has many negative effects on the meaning in life for first aiders. Reduced meaning in life will result in many societal opportunity costs due to decreased health and work engagement. To address this issue, this study conducted a survey to analyze the level of meaning in life of first aiders. The results indicated that the overall level of meaning in life of first aiders is very low. This issue needs to be addressed sooner rather than later, given the increasing trend of emergency response. Based on the results of the study, measures were proposed to reduce PTSD and psychological stability by restoring the meaningfulness of first aiders' lives.

• Asian Pacific Journal of Cancer Prevention
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• 제13권2호
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• pp.559-562
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• 2012

Serum alpha-fetoprotein (AFP) is a significant marker for clinical diagnosis and prognosis evaluation in hepatocellular carcinoma (HCC) patients. However, some proportion of liver cancer patients are AFP-negative (AFP ${\leq}$20ng/ml). In order to study the differences between clinicopathological factors and prognosis of alpha-fetoprotein negative and positive patients, a total of 114 cases (41 AFP-negative and 73 AFP-positive) were selected for our research. By systematically statistical analysis, the results demonstrated that compared with AFP-negative patients, AFP-positive examples were more likely to feature cirrhosis nodules, non-complete neoplasm capsules, and a poor Edmondson-steiner grade. Furthermore, AFP-negative patients demonstrated a favorable long-term prognosis. By univariate analysis and multivariate analysis with Cox's proportional hazards model, multiple tumors were found to be independent risk factors for worse survival of AFP negative patients; however, less tumor-free margins, multiple tumors and Edmondson-steiner grades III/IV, proved to be independent risk factors leading to a poor prognosis of AFP positive cases. Finally, we can infer that high levels of AFP signify a highly malignant tumor and unfavorable prognosis.

• The Korean Journal of Emergency Medical Services
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• 제13권1호
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• pp.97-114
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• 2009

Purpose : This study was performed to identify the knowledge and educational wants for first-aid and its related factors of senior students in elementary schools. Methods : From July 11-25, 2008, this study surveyed 437 elementary school students using a structured questionnaire. Result : Of the study subjects, 47.6% of the subjects had experienced first-aid conditions 25.4% had injuries, 11.0% had indigestion, 10.5% had sprains, 6.2% had acute abdominal pains, 5.9% had brash, and 5.7% had fractures. The experience rates of first-aid conditions were significantly different according to gender, mothers' educational status, means of school attendance and amount of exercise. The experience rate of first-aid education was 71.4%. There was a significant difference with grade, and school reports. They had education about cardiopulmonary resuscitation (52.5%), injury treatment and desmology(48.7%) in a good order. The score of knowledge about first-aid was $13.95{\pm}4.1$ and it was converted on the basis of 100 points, the results were below 50points, and there was a significant difference in grades. Educational wants for first-aid was 64.3%, and as a result of multi-logistic regression analysis of characteristics relating to educational wants, there was a significant difference between gender, grade, mothers' educational status, and amount of exercise. Conclusion : The rate of first-aid experience of elementary school students was high, but as their recognition and knowledge on first-aid was low, the importance of first-aid education and educational wants should be reflected for practical and organized education.

• Molecules and Cells
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• 제38권2호
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• pp.130-137
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• 2015

MicroRNAs (miRNAs) are small, endogenous RNAs that play important gene-regulatory roles by binding to the imperfectly complementary sequences at the 3'-UTR of mRNAs and directing their gene expression. Here, we first discovered that miR-576-3p was down-regulated in human bladder cancer cell lines compared with the non-malignant cell line. To better characterize the role of miR-576-3p in bladder cancer cells, we over-expressed or down-regulated miR-576-3p in bladder cancer cells by transfecting with chemically synthesized mimic or inhibitor. The overexpression of miR-576-3p remarkably inhibited cell proliferation via G1-phase arrest, and decreased both mRNA and protein levels of cyclin D1 which played a key role in G1/S phase transition. The knock-down of miR-576-3p significantly promoted the proliferation of bladder cancer cells by accelerating the progression of cell cycle and increased the expression of cyclin D1. Moreover, the dual-luciferase reporter assays indicated that miR-576-3p could directly target cyclin D1 through binding its 3'-UTR. All the results demonstrated that miR-576-3p might be a novel suppressor of bladder cancer cell proliferation through targeting cyclin D1.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권2호
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• pp.139-143
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• 2004

It was investigated whether developmental characteristics of foundation queens of Bombus ignitus collected in the 4 localities in Korea would be affected by the first oviposition days of them. The first ovipostion day was classified as 1-4 days (immediate early), 5-6days (early), 7-10 days (delayed early), 11-20 days{medium), 21- 40 days (late), and above 41 days (very late). The queen that had the early first oviposition day, i.e., laid eggs so early after starting to be raised indoors, showed much higher rate of colony foundation and progeny-queen production and much shorter period of colony foundation and worker emergence. Besides, the numbers of worker and progeny-queen emerged from the queen that had the early first oviposition day were higher than those of the queen that had the late first oviposition. In results, the queen that had the early first oviposition day could make colony stronger and could make colony formation period shorter, therefore, the first oviposition day of foundation queen was proved to be a criterion for the selection of super colonies when B. ignitus is raised indoors.