• International Journal of Naval Architecture and Ocean Engineering
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• v.13 no.1
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• pp.746-757
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• 2021

To investigate the mechanism of friction-induced vibration and noise of ship water lubricated stern bearings, a two-degree-of-freedom (2-DOF) nonlinear self-excited vibration model is established. The novelty of this work lies in the detailed analysis of influence of different parameters on the stability and nonlinear vibration characteristics of the system, which provides a theoretical basis for the various friction vibration and noise phenomenon and has a very important directive meaning for low noise design of water lubricated stern bearings. The results reveal that the change of any parameter, such as rotating speed of shaft, contact pressure, friction coefficient, system damping and stiffness, has an important influence on the stability and nonlinear response of the system. The vibration amplitudes of the system increase as (a) rotating speed of shaft, contact pressure, and the ratio of static friction coefficient to dynamic friction coefficient increase and (b) the transmission damping between motor and shaft decreases. The frequency spectrum of the system is modulated by the first mode natural frequency, which is continuous multi-harmonics of the first mode natural frequency. The response of the system presents a quasi-periodic motion.

• Journal of The Korean Association For Science Education
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• v.1 no.1
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• pp.29-34
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• 1978

This study is searching for the Historical significance of Background in foundation of London Society and France Loyal Academy. These Academy foundation was contribu ted for establishing the Basis of Scientific theory, method and thought in late century.

• The Journal of the Korean dental association
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• v.49 no.1
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• pp.16-21
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• 2011

Now it is time to move from the scientific basis of CAMBRA into practical methods for dentists to the incorporate concepts into practice. The aim of this article is to provide a clinical guideline for assessment of caries risk and for application for growing children.

• Journal for History of Mathematics
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• v.15 no.2
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• pp.77-82
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• 2002

This paper is concerned with the mathematical concept displayed in Buddhism, which is reasonable enough to consider as a philosophy and encompasses the concept of infinity as scientific as that of mathematics. The purpose of this paper is to examine the changing process of the Buddhism concept of infinity on the basis of time sequence and to combine this with that of mathematics.

• Journal of the Korean Data and Information Science Society
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• v.28 no.3
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• pp.709-720
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• 2017

In healthcare and medical research, many important variables have a measurement error such as body mass index and laboratory data. It is also not easy to collect samples of large size because of high cost and long time required to collect the target patient satisfied with inclusion and exclusion criteria. Beside, the demand for solving a complex scientific problem has highly increased so that a semiparametric regression approach could be of substantial value solving this problem. To address the issues of measurement error, small domain and a scientific complexity, we conduct a multivariable Bayesian smoothing under structural measurement error covariate in this article. Specifically we enhance our previous model by incorporating other useful auxiliary covariates free of measurement error. For the regression spline, we use a radial basis functions with fixed knots for the measurement error covariate. We organize a fully Bayesian approach to fit the model and estimate parameters using Markov chain Monte Carlo. Simulation results represent that the method performs well. We illustrate the results using a national survey data for application.

• CELLMED
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• v.9 no.3
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• pp.4.1-4.8
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• 2019

Now researchers have focused attention on exploring the mechanism of acute responses of heat stress given in heat therapy that ultimately promotes the long term health benefits. Heat therapy is not a new idea rather it was practiced since thousands years back in the form of hot bath, sauna bath, steam room. Similarly in Ayurveda there is very comprehensive description of heat therapy in the form of Svedan karma (Sudation therapy). Svedan is a process to induce sweating artificially in a patient who had already undergone Snehan. Svedan is applied for purification of body, as well as in management of various disorders originated due to vitiation of Vata, Kapha Dosha, Meda Dhatu and musculoskeletal disorders. It produces various beneficial effects by augmenting the Agni like clears the channels, liquefies the deposited Dosha, regulates Vata Dosha, helps in removal and pacification of Dosha, augments metabolism (Agni Deepan), increases appetite, flexibility in body parts, softness and shining of skin, removes coldness, stiffness, drowsiness, improves joint motility. However, Svedana karma is vastly used by Ayurveda Physicians in treatment of various disorders but the mechanisms of beneficial effects produced by Svedan Karma are yet not completely explored on scientific basis. In this article, we will discuss and try to establish a possible mechanism of action of Svedana karma in relation to heat stress, mitochondrial adaptation, heat shock protein (HSP) and glucocorticoids as these are secreted under stressful conditions.

• International Journal of Computer Science & Network Security
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• v.22 no.5
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• pp.289-293
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• 2022

"Tolerance" is considered as an important professional quality of a modern specialist, which is manifested in an active moral position and readiness for constructive interaction with other participants in the pedagogical process; characterized by the manifestation of humanity, tolerance, friendliness, focus on resolving conflict situations in the professional sphere on a non-violent basis. The article considers scientific approaches to understanding the phenomenon of "tolerance". There are a number of factors that significantly affect the formation of tolerance in students. The way to the formation of tolerance is the rejection of social prejudices, negative social stereotypes, the development of an objective attitude to man regardless of his individual characteristics, the formation of skills of tolerant interpersonal interaction, the use of lectures, discussions, games and training in educational work. The purpose of this article is to highlight communicative tolerance as a necessary component of pedagogical practice of future professionals. It was emphasized that tolerance is the basis of religious tolerance and peace, prevention of all kinds of extremism, which are of particular importance for a multinational and multi-religious Ukraine.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.139-160
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• 2017

The bearing mechanism of tunnel-type anchorage (TTA) for suspension bridges is studied. Model tests are conducted using different shapes of plug bodies, which are circular column shape and circular truncated cone shape. The results show that the plug body of the latter shape possesses much larger bearing capacity, namely 4.48 times at elastic deformation stage and 4.54 times at failure stage compared to the former shape. Numerical simulation is then conducted to understand the mechanical and structural responses of plug body and surrounding rock mass. The mechanical parameters of the surrounding rock mass are firstly back-analyzed based on the monitoring data. The calculation laws of deformation and equivalent plastic strain show that the numerical simulation results are rational and provide subsequent mechanism analysis with an established basis. Afterwards, the bearing mechanism of TTA is studied. It is concluded that the plug body of circular truncated cone shape is able to take advantage of the material strength of the surrounding rock mass, which greatly enhances its bearing capacity. The ultimate bearing capacity of TTA, therefore, is concluded to be determined by the material strength of surrounding rock mass. Finally, recommendations for TTA design are proposed and discussed.

• Journal of Engineering Education Research
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• v.5 no.1
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• pp.77-84
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• 2002

The 18th century Joseon(朝鮮) science philosopher Hong Dae-Yong(洪大容, 1731-83) tried to create his own scientific system, while partially keeping the Eastern view of nature and accepting Western science and technology. Most of all, he confirmed that Western science and technology was based on mathematical principles and accurate observation and wrote a math book, [Juhaesuyong(籌解需用)]. Therefore, we have good reason to call him a mathematician. He produced so many achievements that he can be considered a natural scientist in the late Joseon era; he accepted the Eastern view of nature critically and sometimes refused it. He also suggested new and various scientific thoughts, including an infinite universe theory, on the basis of Western scientific thought. Hong Dae-Yong emphasized the importance of practice. He understood the principle of the Western Honcheonui(渾天儀) and manufactured an alarm clock with a craftsman's help. He was an excellent engineer and he set a personal observatory. Considering the level of scientific technology at that time, it is reasonable to regard Hong Dae-Yong as a 'scientific technologist in the 18th century Joseonera', well equipped as a mathematician, a natural scientist, and an engineer. In conclusion, it is with 'mathematical thinking, creative conception, and practical activities' that Hong Dae-Yong maintained throughout his life that we can set a guide to produce excellent Korean scientific technologists and engineers in the 21st century.

• Journal of The Korean Association For Science Education
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• v.40 no.1
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• pp.41-50
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• 2020

Looking at the understanding of scientific concepts from a linguistic perspective, it is very important for students to develop a deep and sophisticated understanding of words used in scientific concept as well as the ability to use them correctly. This study intends to provide the basis for productive knowledge education of scientific words by noting that the foundation of productive knowledge teaching on scientific words is not well established, and by exploring ways to teach the relationship among words that constitute scientific concept in a productive and effective manner. To this end, we extracted the relationship among the words that make up the scientific concept from the text of science textbook by using quantitative text analysis methods, second, qualitatively examined the meaning of the word relationship extracted as a result of each method, and third, we proposed a writing activity method to help improve the productive knowledge of scientific concept words. We analyzed the text of the "Force and motion" unit on first grade science textbook by using four methods of quantitative linguistic analysis: word cluster, co-occurrence, text network analysis, and word-embedding. As results, this study suggests four writing activities, completing sentence activity by using the result of word cluster analysis, filling the blanks activity by using the result of co-occurrence analysis, material-oriented writing activities by using the result of text network analysis, and finally we made a list of important words by using the result of word embedding.