89 research outputs found
A proof of Guo-Wang's conjecture on the uniqueness of positive harmonic functions in the unit ball
No full textGuo-Wang [Calc.Var.Partial Differential Equations,59(2020)] conjectured that
for and , the positive
solution to the equation must be constant. In this paper, we give a proof of this conjecture.Comment: 13 pages. All comments are welcom
Eigensensitivity of damped system with defective multiple eigenvalues
No full textThis paper considers the sensitivity of defective multiple eigenvalues of reducible matrix pencil, the average of eigenvalues is proved to be analytic, the derivatives of the average eigenvalues and the corresponding eigenvector matrices are obtained when the generalized eigenvalue is reducible. The sensitivity of defective multiple eigenvalues of a quadratic eigenvalue problem dependent on several parameters are also obtained by the result of generalized eigenvalue problem. The results are useful for investigating structural optimal design, model updating and structural damage detection
Eigensensitivity analysis for symmetric nonviscously damped systems with repeated eigenvalues
No full textAn efficient algorithm is derived for computation of eigenvalue and eigenvector derivatives of symmetric nonviscously damped systems with repeated eigenvalues. In the proposed method, the mode shape derivatives of the nonviscously damped systems are divided into a particular solution and a homogeneous solution. A simplified method is given to calculate the particular solution by solving a linear equation with non-singularity coefficients, the method is numerically stable and efficient compared to previous methods since the coefficient matrix is non-singularity and numerically stable. The homogeneous solution are computed by the second order derivative of eigenequation. One numerical example is used to illustrate the validity of the proposed method
Studies of the atomization mechanism in a graphite furnace—I. The contents of the gaseous impurities in the furnace and their variations
No full textAudit Service Characteristics and Formation of Audits Committees ¿Empirical Evidence of the China listed company
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Ethmia pingxiangensis Liu 1980
No full textEthmia pingxiangensis Liu, 1980 (Figs. 3, 6, 9) Ethmia pingxiangensis Liu, 1980: 276. Type locality: Guangxi, China. Ethmia amissus Kun, 2001: 210, syn. nov. Type locality: Saraburi, Thailand. Material examined. Holotype: Ƥ, China: Pingxiang City (22 ° 6 ' N, 106 ° 45 'E), Guangxi Zhuang Autonomous Region, 11.vi. 1976, genitalia slide No. 74063 (IZCAS). Additional material. 63, 1 Ƥ, Jingxi County, Bangliang, Guangxi Zhuang Autonomous Region, 31.vii − 5.viii. 2010, coll. Jianhua Huang; 13, Liusanjie Town, Yizhou City, Guangxi Zhuang Autonomous Region, 169 m, 19.viii. 2011, coll. Shulian Hao and Yinghui Sun; 13, Pingxin Town, Yizhou City, Guangxi Zhuang Autonomous Region, 150 m, 16.viii. 2011, coll. Shulian Hao and Yinghui Sun, genitalia slide Nos. WJJ 100403, WJJ 10074 Ƥ, WJJ 110123 (NKU). Male genitalia. (Fig. 6). Uncus 2 / 3 as long as tegumen, narrowed at base, widened gradually to middle; distal half stout, extending obliquely to both sides in V shape, blunt at apex. Gnathos with caudal part trilobed: middle lobe rectangular, apically dentate and concave triangularly at middle; lateral lobes stubbed and broad, shorter than middle lobe, with fine thorns on posterior margin, bluntly rounded apically; oral part membranous, ventrally connected with caudal part by a semi-rounded process, concave anteriorly at middle. Labis about 2 / 5 length of uncus, more or less hammer-shaped, apex blunt. Valva with costa weakly sclerotized, arched dorsally, slightly protruded dorsoapically; sacculus broad, ventral margin obliquely straight; cucullus irregularly shaped, about half length of sacculus, bluntly rounded at apex, with a thin spine at middle on dorsal margin bearing a row of long setae on inner margin, with a strong spine at end of ventral margin, with a cluster of long thick subventral spines on dorsal surface apically exceeding apex of valva. Transtilla narrow-banded. Aedeagus tubular, with a heavily sclerotized ring distally, vesica sclerotized; cornutus needle-like. Diagnosis. This species can easily be separated from its congeners by the forewing having a tadpole-shaped marking on distal 1 / 3 of cell. Distrbution. China (Guangxi); Burma, Thailand, India (Sikkim). Remarks. Liu (1980) described E. pingxiangensis based on one female specimen collected from Guangxi, with illustration of genitalia. After checking the holotype, we found that the adult and genitalia of E. amissus Kun, 2001, recorded from Thailand, Burma and India are identical to those of E. pingxiangensis. We herein synonymize E. amissus with E. pingxiangensis, and describe the male of this species for the first time.Published as part of Wang, Jing-Jing & Wang, Shu-Xia, 2012, One new species and two new synonyms in the genus Ethmia (Lepidoptera: Elachistidae: Ethmiinae), pp. 47-52 in Zootaxa 3260 on page 51, DOI: 10.5281/zenodo.28070
Study on the Seismic Response of a Portal Frame Structure Based on the Transfer Matrix Method of Multibody System
No full textPortal frame structures are widely used in industrial building design but unfortunately are often damaged during an earthquake. As a result, a study on the seismic response of this type of structure is important to both human safety and future building designs. Traditionally, finite element methods such as the ANSYS and MIDAS have been used as the primary methods of computing the response of such a structure during an earthquake; however, these methods yield low calculation efficiencies. In this paper, the mechanical model of a single-story portal frame structure with two spans is constructed based on the transfer matrix method of multibody system (MS-TMM); both the transfer matrix of the components in the model and the total transfer matrix equation of the structure are derived, and the corresponding MATLAB program is compiled to determine the natural period and seismic response of the structure. The results show that the results based on the MS-TMM are similar to those obtained by ANSYS, but the calculation time of the MS-TMM method is only 1/20 of that of the ANSYS method. Additionally, it is shown that the MS-TMM method greatly increases the calculation efficiency while maintaining accuracy
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