• Geomechanics and Engineering
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• v.2 no.1
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• pp.1-18
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• 2010

The analysis of structure response and design of buried structures subjected to dynamic destructive loads have been receiving increasing interest due to recent severe damage caused by strong earthquakes and terrorist attacks. For a comprehensive design of buried structures subjected to blast loads to be conducted, the whole system behaviour including simulation of the explosion, propagation of shock waves through the soil medium, the interaction of the soil with the buried structure and the structure response needs to be simulated in a single model. Such a model will enable more realistic simulation of the fundamental physical behaviour. This paper presents a complete model simulating the whole system using the finite element package ABAQUS/Explicit. The Arbitrary Lagrange Euler Coupling formulation is used to model the explosive charge and the soil region near the explosion to eliminate the distortion of the mesh under high deformation, while the conventional finite element method is used to model the rest of the system. The elasto-plastic Drucker-Prager Cap model is used to model the soil behaviour. The explosion process is simulated using the Jones-Wilkens-Lee equation of state. The Concrete Damage Plasticity model is used to simulate the behaviour of concrete with the reinforcement considered as an elasto-plastic material. The contact interface between soil and structure is simulated using the general Mohr-Coulomb friction concept, which allows for sliding, separation and rebound between the buried structure surface and the surrounding soil. The behaviour of the whole system is evaluated using a numerical example which shows that the proposed model is capable of producing a realistic simulation of the physical system behaviour in a smooth numerical process.

• Structural Engineering and Mechanics
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• v.34 no.2
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• pp.143-157
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• 2010

This paper presents theoretical solutions for the three-dimensional (3D) stress field in an infinite isotropic elastic plate containing a through-the-thickness circular hole subjected to far-field in-plane loads by using Kane and Mindlin's assumption. The dangerous position, where the premature fracture or failure of the plate will take place, the expressions of the tangential stress at the surface of the hole and the out-of-plane stress constraint factor are found in a concise, explicit form. Based on the present theoretical solutions, a comprehensive analysis is performed on the deviated degree of the in-plane stresses from the related plane stress solutions, stress concentration and out-of-plane constraint, and the emphasis has been placed on the effects of the plate thickness, Poisson's ratio and the far-field in-plane loads on the stress field. The analytical solution shows that the effects of the plate thickness and Poisson's ratio on the deviation of the 3D in-plane stress components is obvious and could not be ignored, although their effects on distributions of the in-plane stress components are slight, and that the effect of the far-field in-plane loads is just on the contrary of that of the above two. When only the shear stress is loaded at far field, the stress concentration factor reach its peak value about 8.9% higher than that of the plane stress solutions, and the out-of-plane stress constraint factor can reach 1 at the surface of the hole and is the biggest among all cases considered.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.3
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• pp.189-197
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• 2021

Climate change effects are particularly apparent in many cool-season grasslands in South Korea. Moreover, the probability of climate extremes has intensified and is expected to increase further. In this study, we performed climate change vulnerability assessments in cool-season grasslands based on the analytic hierarchy process method to contribute toward effective decision-making to help reduce grassland damage caused by climate change and extreme weather conditions. In the analytic hierarchy process analysis, vulnerability was found to be influenced in the order of climate exposure (0.575), adaptive capacity (0.283), and sensitivity (0.141). The climate exposure rating value was low in Jeju-do Province and high in Daegu (0.36-0.39) and Incheon (0.33-0.5). The adaptive capacity index showed that grassland compatibility (0.616) is more important than other indicators. The adaptation index of Jeollanam-do Province was higher than that of other regions and relatively low in Gangwon-do Province. In terms of sensitivity, grassland area and unused grassland area were found to affect sensitivity the most with index values of 0.487 and 0.513, respectively. The grassland area rating value was low in Jeju-do and Gangwon-do Province, which had large grassland areas. In terms of vulnerability, that of Jeju-do Province was lower and of Gyeongsangbuk-do Province higher than of other regions. These results suggest that integrating the three aspects of vulnerability (climate exposure, sensitivity, and adaptive capacity) may offer comprehensive and spatially explicit adaptation plans to reduce the impacts of climate change on the cool-season grasslands of South Korea.

• Cross-Cultural Studies
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• v.37
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• pp.233-265
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• 2014

The objective of this article is to emphasize the importance of French grammar and apply effective ways in the course considering the results of investigations conducted by teachers and learners. In the first part, we observed different types of the theory of grammar teaching. The key point in choosing a theory of grammar is to adopt a learning objective defined by the level of learners. To do this, the teacher must find methods that enable learners to achieve a gradual grammatical knowledge. In the second part, we focused on the conscience of the learners et teachers in respect of the grammar's importance. Learners and teachers agreed on the importance of French grammar. However, it is essential to find effective methods that can not only attract the interest of learners but also give students the motivation towards learning French grammar. Regarding the correlation between the learning of linguistic communication and the teaching of grammar, it is very important to familiarize learners with the following facts: - The grammar is not an independent component of the other with regard to the teaching of French. - You can get a satisfactory result on learning grammar provided that it takes place in the course of linguistic communication. What we have proposed in this article is not an absolute solution to improve the course of French, with regard to learning grammar. However, we hope that this study could help to facilitate the teaching of French grammar.

• The Journal of Korean Association of Computer Education
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• v.22 no.4
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• pp.35-45
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• 2019

How future generations perceive coexistence with intelligent robots is an important element of how SW and artificial intelligence education should be designed and conducted. This study conducted a survey of 214 first graders in middle school and looked at differences in understanding and perception of coexistence through empathy and expected problem situations depending on the type of intelligent robot. As a result of the analysis, Firstly, if the form was not explicit, it was recognized as a top-down relationship, and Second, in the case of human form, it was ready to recognize intelligent robots and communicate with them. Third, Many people were feeling Emotion in the Robot shape AI. Fourth, there was a vague sense of uneasiness about simple mechanical robots. The study is meaningful as a case study to confirm awareness of intelligent robots and needs to consider and establish awareness of whether they can coexist and live together with robots by age group as well as middle school students.

• The Southeast Asian review
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• v.28 no.4
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• pp.223-252
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• 2018

The purpose of this paper is to substantially analyse the patterns of complements considering the aspects of not only syntax but also morphology since the concept of complement has been used as a term to analyse the components of a sentence. However, it cannot be denied that there seemed to be limitations due to the partial explanation or different explanations of the same sentence. Thus, this paper aims at dealing with the close relation between sentential components and suffixes to examine the sentence patterns; subject, predicate, object, complement, and adjunct focusing on the terms of complement which has been seen problematic due to incomplete explanations and different interpretations of the same sentence. Finally, this paper synthesises various opinions of many scholars and integrates them to get explicit and practical patterns of complement of a sentence based on not only syntax but also morphology through close relation between sentential components and morphological suffixes.

• Korean Journal of Clinical Pharmacy
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• v.31 no.1
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• pp.61-78
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• 2021

Background and Objective: The use of potentially inappropriate medications (PIMs) increases the risk of negative health outcomes, including drug-related admissions. Tools for structured medication review have been developed to ensure optimal medication use and safety. Here, we aimed to evaluate medication use review (MUR) tools for community-dwelling older patients. Methods: We performed a systematic review of the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement (PRISMA). We searched PubMed, Embase, and the Cochrane Library from 1991 to 2020, excluding tools that are specifically applied to hospitalized patients or nursing home residents. We identified the most common inappropriate medications, drug-disease interactions, drug-drug interactions and prescribing omissions presented among tools. Results: From among 9,788 identified reports screened, 60 met our inclusion criteria; finally, 27 were eligible for data analysis considering originality and up-to-dateness. Most tools presented explicit criteria (93%), and only one was specific to community-dwelling elderly. The most common PIM was tricyclic antidepressants. Use of diltiazem and verapamil in patients with heart failure and the combination of nonsteroidal anti-inflammatory analgesics and warfarin were the most frequent disease-specific PIM and drug-interaction, respectively. Conclusions: Although several medication review tools have been developed for older adults, specific guidelines for community-dwelling populations remain limited. Furthermore, the list of PIMs differed among available tools. In future, specific but integrating MUR tools need to be developed for clinical practice considering this population.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1666-1672
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• 2019

A closed loop wireless transmission method adaptive to mobile unit speed is proposed in this paper. A mobile communication node measures the mobile speed based on the transmitted pilot signals through Doppler frequency estimation, and it changes the transmission period of pilot signals as per estimated mobile speed adaptively. The pilot signals with the different transmission periods are transmitted using the different PN sequences with the previous ones without any explicit information about the new period. The corresponding receiver node can detect and extract the transmitted pilot signals through blind search of the transmitted PN sequences of the pilot signals, and it can demodulate and decode the transmitted information using the channel estimation results based on the detected pilot signals. The performance of the proposed method had been analyzed through the simulation under the fading channel environments and compared with the previous methods. The simulation results showed performance improvement of the proposed method over the existing ones.

• Nutrition Research and Practice
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• v.15 no.1
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• pp.26-37
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• 2021

BACKGROUND/OBJECTIVES: Hyperuricemic nephropathy is a common cause of acute kidney injury. Resveratrol can ameliorate kidney injury, but the explicit mechanism remains unclear. We investigated the effects of resveratrol on the inflammatory response and renal injury in hyperuricemic rats. MATERIALS/METHODS: A rat model of hyperuricemic nephropathy was established by the oral administration of a mixture of adenine and potassium oxinate. Biochemical analysis and hematoxylin and eosin staining were performed to assess the rat kidney function. Enzyme-linked immunosorbent assays were performed to evaluate the immune and oxidative responses. RESULTS: The expression levels of urine albumin and β2-microglobulin were significantly decreased after resveratrol treatment. In addition, the levels of serum creatinine and uric acid were significantly decreased in the resveratrol groups, compared with the control group. The levels of proinflammatory factors, such as interleukin-1β and tumor necrosis factor-α, in kidney tissue and serum were also increased in the hyperuricemic rats, and resveratrol treatment inhibited their expression. Moreover, the total antioxidant capacity in kidney tissue as well as the superoxide dismutase and xanthine oxidase levels in serum were all decreased by resveratrol treatment. CONCLUSIONS: Resveratrol may protect against hyperuricemic nephropathy through regulating the inflammatory response.

• Journal of The Korean Association of Information Education
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• v.24 no.6
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• pp.623-631
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• 2020

In the era of COVID-19 global pandemic, e-learning has become new standards and daily life in the name of 'new normal'. This study developed dialogue e-learning contents as opposed to monologue e-learning which is unidirectional and instructor centered and conducted qualitative user experience evaluation of dialogue e-learning contents. A total number of 20 adult students participated and were individually interviewed. Qualitative data analysis was performed. The findings include students' positive perceptions of dialogue e-learning contents such as empathy for various ideas and new format. With regard to personal preference, 55% of participants preferred dialogue e-learning contents because it enables them to focus and share real experiences. Meanwhile, in terms of learning effects, 60% participants selected monologue e-learning contents and mentioned adequate explanations of concepts and explicit information delivery. Based on the results, suggestions on the design and development of dialogue e-learning contents were presented.