• Advances in nano research
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• 제9권3호
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• pp.157-172
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• 2020

The aim of this present research is the effect of the higher-order terms of the governing equation on the forced longitudinal vibration of a nanorod model and making comparisons of the results with classical nonlocal elasticity theory. For this purpose, the free axial vibration along with forced one under the two various linear and harmonic axial concentrated forces in zigzag Single-Walled Carbon Nanotube (SWCNT) are analyzed dynamically. Three various theories containing the classical theory, which is called Eringen's nonlocal elasticity, along with Rayleigh and Bishop theories (higher-order theories) are established to justify the nonlocal behavior of constitutive relations. The governing equation and the related boundary conditions are derived from Hamilton's principle. The assumed modes method is adopted to solve the equation of motion. For the free axial vibration, the natural frequencies are calculated for the various values of the nonlocal parameter only based on Eringen's theory. The effects of the nonlocal parameter, thickness, length, and ratio of the excitation frequency to the natural frequency over time in dimensional and non-dimensional axial displacements are investigated for the first time.

• 한국실내디자인학회논문집
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• 제23권5호
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• pp.3-13
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• 2014

Typology in Contemporary Architecture wants to escape from the classical typology that has the problems about specific program of structuralism, typical repeatation of customary form. As visible and non-visible things are appeared in contemporary architecture through the analysis of the inner system involving development process of changing itself, typology of contemporary is utilized at a tool of form generation in the process of architect. And it notes that the structural properties of the building system. The form of contemporary architecture has the new connecting strucure not reduced to existing ones. It carries out generative access as a device in order to solve the complexity of society. From this perspective, we analyze the process of projects of contemporary architects that can be typological strategy not representation of post geometric form but a tool of form generation in architectural process. As a result, we can find four characteristics of typology as a tool of form generation; 'interference and mix of program', 'continous slabs', 'rearrangement through relationship setting', 'transformation of multi-layers'. These are expanding to the process that reflect history and context or infer from morphology. Therefore, typology as architectural process of form generation overcomes morphological typology of classical typology and suggests that the different architectural approach having potential possibility.

• Smart Structures and Systems
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• 제21권1호
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• pp.65-74
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• 2018

In this article, an analytic non-classical model for the free vibrations of nanobeams accounting for surface stress effects is developed. The classical continuum mechanics fails to capture the surface energy effects and hence is not directly applicable at nanoscale. A general beam model based on Gurtin-Murdoch continuum surface elasticity theory is developed for the analysis of thin and thick beams. Thus, surface energy has a significant effect on the response of nanoscale structures, and is associated with their size-dependent behavior. To check the validity of the present analytic solution, the numerical results are compared with those obtained in the scientific literature. The influences of beam thickness, surface density, surface residual stress and surface elastic constants on the natural frequencies of nanobeams are also investigated. It is indicated that the effect of surface stress on the vibrational response of a nanobeam is dependent on its aspect ratio and thickness.

• 대한수학회지
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• 제47권6호
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• pp.1269-1282
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• 2010

We in this note consider a new concept, so called $\pi$-McCoy, which unifies McCoy rings and IFP rings. The classes of McCoy rings and IFP rings do not contain full matrix rings and upper (lower) triangular matrix rings, but the class of $\pi$-McCoy rings contain upper (lower) triangular matrix rings and many kinds of full matrix rings. We first study the basic structure of $\pi$-McCoy rings, observing the relations among $\pi$-McCoy rings, Abelian rings, 2-primal rings, directly finite rings, and ($\pi-$)regular rings. It is proved that the n by n full matrix rings ($n\geq2$) over reduced rings are not $\pi$-McCoy, finding $\pi$-McCoy matrix rings over non-reduced rings. It is shown that the $\pi$-McCoyness is preserved by polynomial rings (when they are of bounded index of nilpotency) and classical quotient rings. Several kinds of extensions of $\pi$-McCoy rings are also examined.

• Journal of Mechanical Science and Technology
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• 제15권8호
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• pp.1090-1096
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• 2001

In this paper, new methods for efficiently solving linear acceleration equations of multibody dynamic simulation exploiting sparsity for real-time simulation are presented. The coefficient matrix of the equations tends to have a large number of zero entries according to the relative joint coordinate numbering. By adequate joint coordinate numbering, the matrix has minimum off-diagonal terms and a block pattern of non-zero entries and can be solved efficiently. The proposed methods, using sparse Cholesky method and recursive block mass matrix method, take advantages of both the special structure and the sparsity of the coefficient matrix to reduce computation time. The first method solves the η$\times$η sparse coefficient matrix for the accelerations, where η denotes the number of relative coordinates. In the second method, for vehicle dynamic simulation, simple manipulations bring the original problem of dimension η$\times$η to an equivalent problem of dimension 6$\times$6 to be solved for the accelerations of a vehicle chassis. For vehicle dynamic simulation, the proposed solution methods are proved to be more efficient than the classical approaches using reduced Lagrangian multiplier method. With the methods computation time for real-time vehicle dynamic simulation can be reduced up to 14 per cent compared to the classical approach.

• Journal of Yeungnam Medical Science
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• 제25권2호
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• pp.139-144
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• 2008

Crohn's disease is a chronic inflammatory bowel disease that mainly affects children and young adults. Its cause remains unknown. The incidence of pediatric Crohn's disease is increasing, so it is important for clinicians to be aware of the presentation of this disease in the pediatric population. The majority of patients complain of abdominal pain (72%), with only 25% presenting with the 'classical triad' of abdominal pain, weight loss, and diarrhea. Many children with Crohn's disease present in a 'non-classical' manner, with vague complaints such as lethargy or anorexia, which may be associated with only mild abdominal discomfort. Other symptoms include fever, nausea, vomiting, growth retardation, malnutrition, delayed puberty, psychiatric symptoms, arthropathy, and erythema nodosum. Severe constipation and abdominal distension are uncommon symptoms at diagnosis. We report a case of pediatric Crohn's disease, which was diagnosed after the patient presented with severe constipation and abdominal distension.

• 영어어문교육
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• 제8권2호
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• pp.131-150
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• 2003

The purpose of this paper is to provide two levels of conceptualization of a category such as an absolute category in semantic level and a relative category in pragmatic level on the basis of Aristotelian category theory and prototype category theory. I do not intend to criticize classical category theory and prototype category theory but to show that these two types of category are applied to the different world. Aristotelian categorization is an absolute category because it is based on the possible world called the meta-world and it has an absolute truth value. The members of an absolute category is presented as a set. There is a clear boundary between members and non-members because they are distinguished by the absolute criteria An absolute category is semantic conceptualization. This absolute category is changed into a relative category when it is applied in the real world. A relative category which corresponds to a prototype category is based on the real world called the object world and it has a relative truth value. Here individuals are categorized by the cognition and perception of human beings. A relative category is pragmatic conceptualization. In conclusion, while classical categories which are called absolute categories represent sentence meaning, prototype categories which are called relative categories represent utterance meaning.

• BMB Reports
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• 제44권6호
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• pp.369-374
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• 2011

MHC-I molecules play a critical role in immune surveillance against viruses by presenting peptides to cytotoxic T lymphocytes. Although the mechanisms by which MHC-I molecules assemble and acquire peptides in the ER are well characterized, how MHC-I molecules traffic to the cell surface remains poorly understood. To identify novel proteins that regulate the intracellular transport of MHC-I molecules, MHC-I-interacting proteins were isolated by affinity purification, and their identity was determined by mass spectrometry. Among the identified MHC-I-associated proteins was Tmp21, the human ortholog of yeast Emp24p, which mediates the ER-Golgi trafficking of a subset of proteins. Here, we show that Tmp21 binds to human classical and non-classical MHC-I molecules. The Tmp21-MHC-I complex lacks ${\beta}_2$-microglobulin, and the number of the complexes is increased when free MHC-I heavy chains are more abundant. Taken together, these results suggest that Tmp21 is a novel protein that preferentially binds to ${\beta}_2$-microglobulin-free MHC-I heavy chains.

• BMB Reports
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• 제50권5호
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• pp.269-274
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• 2017

The biological activities of macrophage migration inhibitory factor (MIF) might be mediated through a classical receptor-mediated or non-classical endocytic pathway. JAB1 (C-Jun activation domain-binding protein-1) promotes the degradation of the tumor suppressor, p53, and the cyclin-dependent kinase inhibitor, p27. When MIF and JAB1 are bound to each other in various intracellular sites, MIF inhibits the positive regulatory effects of JAB1 on the activity of AP-1. The intestinal parasite, Anisakis simplex, has an immunomodulatory effect. The molecular mechanism of action of As-MIF and human JAB1 are poorly understood. In this study, As-MIF and hJAB1 were expressed and purified with high solubility. The structure of As-MIF and hJAB1 interaction was modeled by homology modeling based on the structure of Ace-MIF. This study provides evidence indicating that the MIF domain of As-MIF interacts directly with the MPN domain of hJAB1, and four structure-based mutants of As-MIF and hJAB1 disrupt the As-MIF-hJAB1 interaction.

• Advances in nano research
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• 제3권4호
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• pp.177-191
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• 2015

In this article, various higher-order shear deformation theories (HSDTs) are developed for bending and buckling behaviors of nanowires including surface stress effects. The most important assumption used in different proposed beam theories is that the deflection consists of bending and shear components and thus the theories have the potential to be utilized for modeling of the surface stress influences on nanowires problems. Numerical results are illustrated to prove the difference between the response of the nanowires predicted by the classical and non-classical solutions which depends on the magnitudes of the surface elastic constants.