• Computational Structural Engineering
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• v.10 no.1
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• pp.159-171
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• 1997

This study investigates the stress distribution in a transversely isotropic medium containing a spheroidal cavity where the medium is under uniaxial tension in z-direction in one case and pure shear in the plane of isotropy in another case. The technical approach used in this study combines exact analytical and numerical methods. The exact analytical method is based upon three potential functions taken in terms of the Legendre associated functions of the first and second kind. The numerical method is based upon the finite difference approach. Numerical results concerning the two loading conditions with five anisotropic materials are presented.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.214-218
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• 2002

So far, many kinds of researches on the ceramic chip components and MCM-C RF module especially on the 3-dimensional ceramic module using embedded passives have been performed. LTCC system has many kinds of advantages, like low lass, low cost of process, stability of process etc.. But it's so hard to adjust the characteristics of passives in ceramic module after fabrication. So the exact prediction of behavior of components in high frequency region upper than 2 GHz must be made. In this procedure, the exact measurement is need. In this study, many kinds of measurement Jigs are compared and optimized, and measurement methods of each parameter are designed.

• Journal of the Korean Society of Safety
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• v.13 no.3
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• pp.163-170
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• 1998

The differential quadrature method (D.Q.M.) is applied to computation of eigenvalues of small-amplitude free vibration for horizontally curved beams including a warping contribution. Fundamental frequencies are calculated for a single-span, curved, wide-flange beam with both ends simply supported or clamped, or simply supported-clamped end conditions. The results are compared with existing exact solutions and numerical solutions by other methods for cases in which they are available. The differential quadrature method gives good accuracy even when only a limited number of grid points is used.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.11
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• pp.55-61
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• 1999

The torsional and axial vibrations of shaft system have been calculated independently because of both the limitation of computing time and the complexity of crankshaft model. In actual system, however, the torsional and axial vibrations are coupled. Therefore, in recent, many works in the coupled vibration analysis have been done to find out the more exact dynamic behavior of shaft system. The crankshaft model is very important in the vibration analysis of shaft system because most of excitation forces act on the crankshaft. It is, however, difficult to establish an exact model of crankshaft since its shape is very complex. In this work, an efficient method is proposed to construct the stiffness matrix of crankshaft using a finite element model of half crankthrow. The proposed and existing methods are compared by applying to both a simple thick beam with circular cross section and an actual crankshaft.

• Journal of Convergence Korean Medicine
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• v.1 no.1
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• pp.5-15
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• 2021

Objectives: To review the concept of Moebius syndrome. Methods: Literature search was done to study definition, epidemiology, pathophysiology, clinical feature, and treatment of Moebius syndrome. Pubmed, RISS, Google scholarship and uptodate scholastic were used in the research. Search words were 'Moebius syndrome', 'treatment of Moebius syndrome'. Only English and Korean studies were assessed. Results: Moebius syndrome is rare disease characterized by nonprogressive congenital uni- or bi-lateral facial (VII cranial nerve) and abducens (VI cranial nerve) palsy. This facial palsy is found across the world, and its incidence is approximately 1 per 250,000. Moebius is diagnosed by clinical features. Facial palsy, eye abduction problem, limb deformities, global cerebral nerve impairment can be shown. Rehabilitation, smile surgery, and acupuncture can be used to treat this. Conclusion: Moebius syndrome's epidemiology, pathogenesis, treatment is still not fully revealed. It is known to be a congenital disease which didn't have exact treatment except surgery. But, it needs further study about exact treatment, diagnosis, and pathogenesis.

• Journal of Oral Medicine and Pain
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• v.49 no.1
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• pp.5-11
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• 2024

Halitosis is defined as a nasty odor emanating through the mouth and is primarily related to the enhanced concentration of volatile sulfur compounds (VSCs). VSC measurements have been commonly used for experimental comparison and clinical diagnosis. As quantitative methods for comparative analyses of oral malodor, gas chromatography devices have been most commonly used to quickly and easily determine the concentration of several gas components of VSCs, which are agents primarily responsible for halitosis. The concentrations of VSCs fluctuate dynamically depending on contributing factors, including various oral/systemic conditions, intake of medicine and food/drink, oral hygiene, and even routine daily activities. Therefore, the exact analysis of VSCs requires the appropriate standardization of not only exact measurement techniques but also participant conditioning with scientific considerations. Thus, this paper describes the experimental standardizations commonly recommended in previous literature and their scientific background.

• Structural Engineering and Mechanics
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• v.5 no.5
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• pp.635-644
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• 1997

The paper reviews the implementation and evaluation of exact methods for the computation of transcendental structural eigenvalues, i.e., critical buckling loads and natural frequencies of undamped vibration, on multiple instruction, multiple data parallel computers with distributed memory. Coarse, medium and fine grain parallel methods are described with illustrative examples. The methods are compared and combined into hybrid methods whose performance can be predicted from that of the component methods individually. An indication is given of how performance indicators can be presented in a generic form rather than being specific to one particular parallel computer. Current extensions to permit parallel optimum design of structures are outlined.

• Structural Engineering and Mechanics
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• v.22 no.1
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• pp.107-130
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• 2006

The paper deals with the numerical solution of the dynamic problem of masonry structures. Masonry is modelled as a non-linear elastic material with zero tensile strength and infinite compressive strength. Due to the non-linearity of the adopted constitutive equation, the equations of the motion must be integrated directly. In particular, we apply the Newmark or the Hilber-Hughes-Taylor methods implemented in code NOSA to perform the time integration of the system of ordinary differential equations obtained from discretising the structure into finite elements. Moreover, with the aim of evaluating the effectiveness of these two methods, some dynamic problems, whose explicit solutions are known, have been solved numerically. Comparisons between the exact solutions and the corresponding approximate solutions obtained via the Newmark and Hilber-Hughes-Taylor methods show that in the cases under consideration both numerical methods yield satisfactory results.

• The Korean Journal of Applied Statistics
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• v.22 no.4
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• pp.781-792
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• 2009

At an early stage of genomic investigations, a small sample of microarrays is used in gene expression experiments to identify small subsets of candidate genes for a further accurate investigation. Unlike the statistical analysis methods for a large sample of microarrays, an appropriate statistical method for identifying small subsets is a randomization test that provides exact P values. These exact P values from a randomization test for a small sample of microarrays are discrete. The possible existence of differentially expressed genes in the sample of a full set of genes can be tested for the null hypothesis of a uniform distribution. Subsets of smaller P values are of prime interest for a further accurate investigation and identifying these outlier cells from a multinomial distribution of P values is possible by M test of Fuchs et al. (1980). Above all, the genome-wide gene expressions in microarrays are correlated, but the majority of statistical analysis methods in the microarray analysis are based on an independence assumption of genes and ignore the possibly correlated expression levels. We investigated with simulation studies the effect that correlated gene expression levels could have on the randomization test results and M test results, and found that the effects are often not ignorable.