• Proceedings of the Computational Structural Engineering Institute Conference
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• 1995.10a
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• pp.153-160
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• 1995

Mixed finite element formulations for incompressible materials show pressure oscillations or pressure modes in four-node quadrilateral elements. The criterion for the stability in the pressure solution is the so-called Babufka-Brezzi stability condition, and the four-node elements based on mixed variational principles do not appear to satisfy this condition. In this study, a pressure continuity residual based on the pressure discontinuity at element edges is used to study the stabilization of pressure solutions in bilinear displacement-constant pressure four-node quadrilateral elements. It is shown that the pressure solutions, although stable, exhibit sensitivity to the stabilization parameters.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.547-552
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• 2007

In this note, we extends some of the results of Liu [Fuzzy Sets and systems 157 (2006) 869-878]. This extension consists of a simple proof involving weighted functions and their preference index. We also give an elementary simple proof of the maximum entropy weighting function problem with a given preference index value without using any advanced theory like variational principles or without using Lagrangian multiplier methods.

• Journal of Sasang Constitutional Medicine
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• v.22 no.4
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• pp.1-9
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• 2010

1. Objectives This paper investigates the origin, the progressive changes and the constructive principles of Palmulgunja-tang (八物君子湯). 2. Methods Palmulgunja-tang and other related prescriptions were analyzed in terms of their pathological indications, based on previous literature including "Donguisusebowon Chobongwon (東醫壽世保元 草本卷)", "Donguisusebowon Gabobon (東醫壽世保元 甲午本)", "Donguisusebowon Sinchukbon (東醫壽世保元 辛丑本)" and "Dongmuyugo (東武遺稿)". 3. Results and Conclusions 1) The Palmulgunja-tang most likely originates from Paljin-tang introduced in "Donguisusebowon Chobongwon (東醫壽世保元 草本卷)". Paljin-tang progressively transformed into Seungyangpalmul-tang ("Donguisusebowon Gabobon (東醫壽世保元 甲午本)") and ultimately into Palmulgunja-tang ("Donguisusebowon Sinchukbon (東醫壽世保元 辛丑本)"), a prescription appropriate for usage in the Ulgwang symptomatology (鬱狂證). Also, Seungyangikgi-tang in "Donguisusebowon Sinchukbon (東醫壽世保元 辛丑本)" can be presumed to have been affected by Seungyangpalmul-tang. 2) The variational prescriptions (變方) of Palmulgunja-tang shows increasing Seungyang (升陽) effect in order of Baekhaogunja-tang, Sipjeondaebo-tang, Palmulgunja-tang, and Doksampalmul-tang. 3) Palmulgunja-tang is composed of 8 herbs. Of these, Paeoniae Radix Alba (白芍藥), Glycyrrhizae Radix(甘草), Angelicae gigantis Radix (當歸), and Cnidii Rhizoma (川芎) fortify the Soeumin Spleen Element (脾元). Ginseng Radix (人蔘) and Astragali Radix (黃芪) support the ascension of Yang, whereas Atractlodis Rhizoma White (白朮) and Citrus unshiu (陳皮) encourage the descension of Yin.

• Journal of Magnetics
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• v.21 no.1
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• pp.6-11
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• 2016

The magnetic anisotropy energy (MAE) and the saturation magnetization $B_s$ of (110) $Fe_nCo_n$ heterostructures with n = 1, 2, and 3 are investigated in first-principles within the density functional theory by using the precise full-potential linearized augmented plane wave (FLAPW) method. We compare the results employing two different exchange correlation potentials, that is, the local density approximation (LDA) and the generalized gradient approximation (GGA), and include the spin-orbit coupling interaction of the valence states in the second variational way. The MAE is found to be enhanced significantly compared to those of bulk Fe and Co and the magnetic easy axis is in-plane in agreement with experiment. Also the MAE exhibits the in-plane angle dependence with a two-fold anisotropy showing that the $[1{\overline{I}}0]$ direction is the most favored spin direction. We found that as the periodicity increases, (i) the saturation magnetization $B_s$ decreases due to the reduced magnetic moment of Fe far from the interface, (ii) the strength of in-plane preference of spin direction increases yielding enhancement of MAE, and (iii) the volume anisotropy coefficient decreases because the volume increase outdo the MAE enhancement.

• Journal of Sasang Constitutional Medicine
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• v.23 no.2
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• pp.184-193
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• 2011

1. Objectives: This paper investigates the origin, the progressive changes and the constructive principles of Yangkyuksanhwa-tang (凉膈散火湯). 2. Methods: Yangkyuksanhwa-tang and other related prescriptions were analyzed in terms of their pathological indications, based on previous literature including "Donguisusebowon Chobongwon (東醫壽世保元 草本卷)", "Donguisusebowon Gabobon (東醫壽世保元 甲午本)", "Donguisusebowon Sinchukbon (東醫壽世保元 辛丑本)" and "Dongmuyugo (東武遺稿)". 3. Results and Conclusion: 1) The Yangkyuksanhwa-tang most likely originates from Sodokeum, Yangkyuksan, Baekho-tang and Indongdeung. 2) Sodoksanhwa-tang introduced in "Donguisusebowon Chobongwon (東醫壽世保元 草本卷)" progressively transformed into Chungyangsanghwa-tang ("Donguisusebowon Gabobon (東醫壽世保元 甲午本)") and ultimately into Yangkyuksanhwa-tang ("Donguisusebowon Sinchukbon (東醫壽世保元 辛丑本)"), a prescription appropriate for usage in the Sangso symptomatology (上消證). 3) Yangkyuksanhwa-tang is composed of 9 herbs. Of these, Schixonepetae herba(荊芥), Ledebouriellae Radix(防風), Forsythiae fructus(連翹), Menthae Herba(薄荷), Gardeniae fructus(梔子) scatter the Hwa-qi(火氣), and Rehmanniae Radix(生地黃), Gypsum fibrosum(石膏), Anemarrhenae(知母) put off the Stomach-heat(胃熱), whereas Lonicerae caulis(忍冬藤) support the prevention of carbunculosis(癰疽).

• Structural Engineering and Mechanics
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• v.6 no.6
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• pp.711-725
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• 1998

Mixed finite element formulations for incompressible materials show pressure oscillations or pressure modes in four-node quadrilateral elements. The criterion for the stability in the pressure solution is the so-called Babu$\check{s}$ka-Brezzi stability condition, and the four-node elements based on mixed variational principles do not appear to satisfy this condition. In this study, a pressure continuity residual based on the pressure discontinuity at element edges proposed by Hughes and Franca is used to study the stabilization of pressure solutions in bilinear displacement-constant pressure four-node quadrilateral elements. Also, a solid mechanics problem is presented by which the stability of mixed elements can be studied. It is shown that the pressure solutions, although stable, are shown to exhibit sensitivity to the stabilization parameters.

• Structural Engineering and Mechanics
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• v.26 no.1
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• pp.31-42
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• 2007

The unsymmetric finite element formulation has been proposed recently to improve predictions from distorted finite elements. Studies have also shown that this special formulation using parametric functions for the test functions and metric functions for the trial functions works surprisingly well because the former satisfy the continuity conditions while the latter ensure that the stress representation during finite element computation can retrieve in a best-fit manner, the actual variation of stress in the metric space. However, a question that remained was whether the unsymmetric formulation was variationally correct. Here we determine that it is not, using the simplest possible element to amplify the principles.

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.464-469
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• 2000

In order to analyze effectively the discontinuous parts such as holes or notches included in mechanical structures by the finite element method, a singular finite element for orthotropic materials. is proposed. This singular element is formulated by the Trefftz method and the hybrid variational principles, which the displacements and stresses are simultaneously assumed using the Trefftz functions. Through several numerical tests, it is shown that the proposed singular element is very efficient for the accurate stress analysis of the various types of discontinuous parts.

• Journal of The Korean Astronomical Society
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• v.34 no.4
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• pp.203-207
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• 2001

SPH is the shorthand for Smoothed Particle Hydrodynamics. This method is a Lagrangian method which means that it involves following the motion of elements of fluid. These elements have the characteristics of particles and the method is called a particle method. A useful review of SPH (Monaghan 1992) gives the basic technique and how it can be applied to numerous problems relevant to astrophysics. You can get some basic SPH programs from http) /www.maths.monash.edu.au/jjm/sphlect In the present lecture I will assume that the student has studied this review and therefore understands the basic principles. In today's lecture I plan to approach the equations from a different perspective by using a variational principle.

• Journal of Korean Association for Spatial Structures
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• v.7 no.1 s.23
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• pp.55-62
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• 2007

The Paper presents three methods for calculating the natural frequencies of cantilevered curved Beams. A summary is given of the development of two techniques: theoretic value and the result of the experiment. Theoretic value of curved beam vibration analysis are derived from complementary variational principles assuming as unknown stress-displacement result fields. In order to perform free vibration analysis of curved beam, Aluminum-made cantilevered curved beam is used in experiment. Experimental input and output signals are derived from the impact hammer and the one accelemeter are amplificated by an amplifier. The validity of the modal analysis method