• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제26권2호
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• pp.108-120
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• 2022

We considered qualitative behaviour of the generalization of Einstein's model of Brownian motion when the key parameter of the time interval of free jump degenerates. Fluids will be characterised by number of particles per unit volume (density of fluid) at point of observation. Degeneration of the phenomenon manifests in two scenarios: a) flow of the fluid, which is highly dispersing like a non-dense gas and b) flow of fluid far away from the source of flow, when the velocity of the flow is incomparably smaller than the gradient of the density. First, we will show that both types of flows can be modeled using the Einstein paradigm. We will investigate the question: What features will particle flow exhibit if the time interval of the free jump is inverse proportional to the density and its gradient ? We will show that in this scenario, the flow exhibits localization property, namely: if at some moment of time t₀ in the region, the gradient of the density or density itself is equal to zero, then for some T during time interval [t₀, t₀ + T] there is no flow in the region. This directly links to Barenblatt's finite speed of propagation property for the degenerate equation. The method of the proof is very different from Barenblatt's method and based on the application of Ladyzhenskaya - De Giorgi iterative scheme and Vespri - Tedeev technique. From PDE point of view it assumed that solution exists in appropriate Sobolev type of space.

• Parasites, Hosts and Diseases
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• 제60권3호
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• pp.155-161
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• 2022

All living organisms are destined to die. Cells, the core of those living creatures, move toward the irresistible direction of death. The question of how to die is critical and is very interesting. There are various types of death in life, including natural death, accidental death, questionable death, suicide, and homicide. The mechanisms and molecules involved in cell death also differ depending on the type of death. The dysenteric amoeba, E. histolytica, designated by the German zoologist Fritz Schaudinn in 1903, has the meaning of tissue lysis; i.e., tissue destroying, in its name. It was initially thought that the amoebae lyse tissue very quickly leading to cell death called necrosis. However, advances in measuring cell death have allowed us to more clearly investigate the various forms of cell death induced by amoeba. Increasing evidence has shown that E. histolytica can cause host cell death through induction of various intracellular signaling pathways. Understanding of the mechanisms and signaling molecules involved in host cell death induced by amoeba can provide new insights on the tissue pathology and parasitism in human amoebiasis. In this review, we emphasized on the signaling role of NADPH oxidases in reactive oxygen species (ROS)-dependent cell death by pathogenic E. histolytica.

• Restorative Dentistry and Endodontics
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• 제48권1호
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• pp.5.1-5.22
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• 2023

This systematic review and network meta-analysis aimed to answer the following focused research question: "Does the type of endodontic sealer affect the postoperative pain in patients who received endodontic treatment?" Different databases and grey literature were surveyed. Only one randomized controlled trial were included. The risk of bias in the studies was evaluated by using the Cochrane Collaboration's tool. A random-effects meta-analysis was conducted to compare the risk and intensity of postoperative pain. The quality of the body of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation approach. Out of 11,601 studies, 15 remained for qualitative analyses and 12 for meta-analysis. Seven studies were classified at high risk of bias, and 8 studies raised some concerns. No significant differences between the endodontic materials were observed in the direct comparisons, both in risk and in intensity of postoperative pain (pairwise comparisons with 2 studies: I² = 0%; p > 0.05 and 8 studies: I² = 23%; p > 0.05, respectively). The certainty of the evidence was graded as low or moderate. There was no difference in the risk and intensity of postoperative pain after filling with different endodontic sealers. Further systematic reviews should be conducted.

• 유통과학연구
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• 제20권3호
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• pp.33-43
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• 2022

Purpose: More and more marketers use social media platforms to create and spread information called Marketer Generated Content (MGC) to inform consumers of products. MGC often embeds product purchase links, thus directing consumers to online distribution channels for online purchases. This study examined the effect of social media MGC on consumers' willingness to buy online in the anchor of consumers' perspective to answer the question of "how social media generated content support corporate online distribution". Research design, data, and methodology: According to the means-end-chain theory, we introduce perceived value and continuous following intention as chain mediators to explain the mechanism of MGC influence on consumers' online purchase intention and consider product type to discuss boundary conditions. Two experiments were designed to test hypothesizes. Results and Conclusion: First, emotional MGC (vs. informational MGC) has lower (higher) perceived utility (hedonic) value. Second, perceived value has a significant mediate role in the effect of MGC on continuous following intention. Third, perceived value and continuous following intention significantly and sequentially mediated the effect of MGC on online purchase intention. Through the sequential mediations of perceived utility value and continuous following intention, Informational MGC of search products significantly increase online purchase intentions. Another parallel sequential mediation, including perceived hedonic, emotional MGC of experience products, partially enhanced online purchase intentions. Finally, this study gives implications for how corporates can use social media MGC to promote product sales online.

• 천문학회보
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• 제46권1호
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• pp.27.3-27.3
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• 2021

Supernova (SN) cosmology is based on the assumption that the width-luminosity relation (WLR) in the type Ia SN luminosity standardization would not vary with progenitor age. Unlike this expectation, recent age datings of stellar populations in host galaxies have shown significant correlations between progenitor age and Hubble residual (HR). It was not clear, however, how this correlation arises from the SN luminosity standardization process, and how this would impact the cosmological result. Here we show that this correlation originates from a strong progenitor age dependence of the WLR and color-luminosity relation (CLR), in the sense that SNe from younger progenitors are fainter each at given light-curve parameters x1 and c. This is reminiscent of Baade's discovery of two Cepheid period-luminosity relations, and, as such, causes a serious systematic bias with redshift in SN cosmology. We illustrate that the differences between the high-z and low-z SNe in the WLR and CLR, and in HR after the standardization, are fully comparable to those between the correspondingly young and old SNe at intermediate redshift, indicating that the observed dimming of SNe with redshift is most likely an artifact of over-correction in the luminosity standardization. When this systematic bias with redshift is properly taken into account, there is no evidence left for an accelerating universe, and the SN data now support a decelerating cosmic expansion. Since the SN cosmology has long been considered as the most direct evidence for an accelerating universe with dark energy, this finding poses a serious question to one of the cornerstones of the concordance model.

• 한국보건간호학회지
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• 제23권2호
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• pp.207-218
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• 2009

Purpose: In an attempt to develop a parental health improvement education program for day care children, survey questions were devised to measured the extent of parental health knowledge, health-guidance execution and needs. Method: Participants were 727 parents whose children attended daycare centers in J province informed consent was provided prior to participation. Result: Respondents were overwhelmingly (91.6%) mothers. Questions with high percentage of incorrect answers were "What should I do if my child swallows harmful drugs, bleach or detergents?" (98.1%) and "What should I do if insects or other bugs enter my child's ear?" (96.6%). In most cases, parental health-guidance execution exceeded 90% except in response to the survey question "Does your child have a dental check-up every 6 months" (51%). Taken together, parental education is necessary concerning growth and development (12.8%), nutrition (12.1%), healthy life styles (10.3%) and general health issues (10.0%). Conclusions: Parental health knowledge about preschooler's health varies with degree of income, education and type of employment. Consideration of these variables is important in a parental health education program.

• 수산경영론집
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• 제54권3호
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• pp.17-28
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• 2023

In this study, a conjoint analysis was conducted to derive a combination of fishing quota management system by fish species preferred by fishermen. In the analysis, detailed levels were set according to each attribute of the system. For analysis, this study conducted a design question survey for conjoint analysis on 303 fishermen engaged in fishing activities in the offshore and coastal sea. The Conjoint analysis was conducted on all fishermen, offshore fishermen and coastal fishermen. In addition, an analysis was conducted on TAC system participants and non-TAC system participants, and the targets were classified for comparison according to the characteristics of fishermen. Fishermen's preference for the system confirmed for six attribute ("catching fish even if there is no fishing quota", "how to allocate fishing quota", "fishing quota management agency", "upper limit of fishing quota," "Possibility of Trading in the Fishing Quota", and "Application of Other Regulations.") and the detailed level of each attribute. As a result of the analysis of the importance of attributes, fishermen thought that "fishing quota management agency (24.1%)" was very important, and "catching fish even if there is no fishing quota (23.9%)" and "how to allocate fishing quotas (22.9%)" were also given some importance.

• 전자통신동향분석
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• 제38권6호
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• pp.1-11
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• 2023

Large language models seem promising for handling reasoning problems, but their underlying solving mechanisms remain unclear. Large language models will establish a new paradigm in artificial intelligence and the society as a whole. However, a major challenge of large language models is the massive resources required for training and operation. To address this issue, researchers are actively exploring compact large language models that retain the capabilities of large language models while notably reducing the model size. These research efforts are mainly focused on improving pretraining, instruction tuning, and alignment. On the other hand, chain-of-thought prompting is a technique aimed at enhancing the reasoning ability of large language models. It provides an answer through a series of intermediate reasoning steps when given a problem. By guiding the model through a multistep problem-solving process, chain-of-thought prompting may improve the model reasoning skills. Mathematical reasoning, which is a fundamental aspect of human intelligence, has played a crucial role in advancing large language models toward human-level performance. As a result, mathematical reasoning is being widely explored in the context of large language models. This type of research extends to various domains such as geometry problem solving, tabular mathematical reasoning, visual question answering, and other areas.

• 복식문화연구
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• 제31권5호
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• pp.627-639
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• 2023

This study seeks to increase the satisfaction of elderly men when purchasing and wearing ready-to-wear clothes by designing a slacks pattern suitable for their body type, which is determined by analyzing their lower bodies using virtual avatars and 3D virtual simulation system. The study found the following. First, based on virtual visualization of the comparison slacks pattern, the waistline position was consistently the lowest scored question among the evaluation survey items. Interpretation of this dissatisfaction suggests that, because the front waistline falls below the abdomen, the lower body, and especially the abdominal shape, is unpleasantly emphasized. Second, by using a virtual simulation system, the study developed a new slacks pattern that considered the concerns of elderly men. The primary measurement changes were as follows: front waist girth W/4+1.5cm+0.5cm, back waist girth W/4+1.5cm-0.5cm, front hip girth H/4+2.5cm-0.5cm, back hip girth H/4+2.5cm+0.5cm. Third, the new slacks pattern's appearance was evaluated more highly than the comparison pattern, confirming the new pattern's appropriateness for elderly men. This study demonstrates how slacks and other clothing patterns designed in a 3D virtual garment simulator can be used to design more appealing clothing for elderly men, increasing the satisfaction of wearing ready-made clothes at older ages.

• 한국초등과학교육학회지:초등과학교육
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• 제40권2호
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• pp.162-174
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• 2021

본 연구는 초등 예비교사들이 스마트 테크놀로지 활용 과학 수업을 계획할 때 발생하는 질문의 유형과 작성한 수업과정안의 특징을 살펴보았다. 이를 위해 96명의 예비교사들이 작성한 수업과정안과 질문을 수집하였다. 그 결과는 다음과 같다. 첫째, 예비교사들은 시뮬레이션 앱, 정보제공 앱, clicker 평가 앱, 천문관측 앱을 활용하였으며, 수업의 도입 단계에서는 시뮬레이션 앱과 clicker 평가 앱을, 전개 단계에서는 시뮬레이션 앱을, 정리 단계에서는 clicker 평가 앱을 가장 많이 활용하였다. 둘째, 스마트 테크놀로지를 사용하는 주체는 학생인 경우가 교사에 비해 높게 나타났으며, 수업의 전개 단계에서 그 특징이 더 두드러졌다. 셋째, 수업과정안에서 활용한 스마트 테크놀로지의 콘텐츠 유형은 체험형이 가장 높게 나타났으며, 도구형, 자원형 순으로 나타났다. 이에 비해 상호작용지원형이나 학습기회확장형은 상대적으로 적게 나타났다. 넷째, 예비 교사들이 작성한 과정안에는 학생들이 직접 실험이나 체험하는 기회를 제공하는 대신 체험형 스마트 테크놀로지를 활용하여 가상 체험으로 대체하는 경우가 다수 나타났다. 다섯째, 예비 초등 교사들은 스마트 테크놀로지를 활용한 과학 수업을 계획하면서 다양한 질문을 제기하였으며, 총 7개 범주 25개의 질문 유형이 나타났다.