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New ommatids of Ommatinae(Coleoptera:Archostemata:Ommatidae)from the Yixian Formation of western Liaoning,China

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Progress in Natural Science:Materials International 2007年第7期17卷 803-811页

作者： Shih chung Kun Beijing 100037 Capital Normal University China Key Laboratory of Insect Evolution & Environment Change College of Life Science

Four new fossil species of the family Ommatidae from the Yixian Formation of western Liaoning,China are described. Two of them belong to tribe Brochocoleini:Brochocoleus sulcatus *** Brochocoleus angustus *** other two refer to tribe Ommatini:Cionocoleus planiusculus *** Cionocoleus cervicalis *** diagnosis of Brochocoleus and Cionocoleus, respectively,are revised.A preliminary analysis of geographical distribution suggests a possible migration pathway of the genus Bro- *** relationship between the genus Cionocoleus and the extant family Crowsoniellidae is briefly discussed.

关键词： Ommatidae Brochocoleus Cionocoleus new species Yixian Formation

Forms and Aesthetics of Bridges

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Engineering 2018年第2期4卷 103-112页

作者： Man-chung Tang Chinese Academy of Engineering Beijing 100088 China US National Academy of Engineering Washington DC 20001 USA T.Y. Lin International Group San Francisco CA 94104 USA

The objective of a bridge design is to produce a safe bridge that is elegant and satisfies all functionality requirements, at a cost that is acceptable to the owner. A successful bridge design must be natural, simple, original, and harmonious with its surroundings. Aesthetics is not an additional consideration in the design of a bridge, but is rather an integral part of bridge design. Both the structural configuration and the aesthetics of a bridge must be considered together during the conceptual design stage. To achieve such a task, the bridge design engineer must have a good understanding of structural theory and bridge aesthetics.

关键词： Form Aesthetics Bridge Concept Design Environment

ADDITIVE PERTURBATIONS OF LOCAL C-SEMIGROUPS

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Acta Mathematica Scientia 2015年第6期35卷 1566-1576页

作者： chung-Cheng KUO Department of Mathematics Fu Jen University

In this paper, we apply the contraction mapping theorem to establish some bounded and unbounded additive perturbation theorems concerning local C-semigroups. Some growth conditions of perturbations of local C-semigrou... 详细信息

关键词： local C-semigroup generator abstract Cauchy problem perturbation

A perturbation-incremental scheme for studying Hopf bifurcation in delayed differential systems

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Science China(Technological Sciences) 2009年第3期52卷 698-708页

作者： chung Kwok Wai Department of Mathematics City University of Hong Kong Kowloon

A new method, called perturbation-incremental scheme (PIS), is presented to investigate the periodic solution derived from Hopf bifurcation due to time delay in a system of first-order delayed differential equations. The method is summarized as three steps, namely linear analysis at critical value, perturba- tion and increment for continuation. The PIS can bypass and avoid the tedious calculation of the center manifold reduction (CMR) and normal form. Meanwhile, the PIS not only inherits the advantages of the method of multiple scales (MMS) but also overcomes the disadvantages of the incremental harmonic balance (IHB) method. Three delayed systems are used as illustrative examples to demonstrate the validity of the present method. The periodic solution derived from the delay-induced Hopf bifurcation is obtained in a closed form by the PIS procedure. The validity of the results is shown by their consis- tency with the numerical simulation. Furthermore, an approximate solution can be calculated in any required accuracy.

关键词： delayed differential equation perturbation-incremental scheme Hopf bifurcation synchronization center manifold

Distributional Methods for a Class of Functional Equations and Their Stabilities

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Acta Mathematica Sinica,English Series 2007年第11期23卷 2017-2026页

作者： Jae Young chung Department of Mathematics Kunsan National UniversityKunsan 573-701South Korea

We consider a class of n-dimensional Pompeiu equations and that of Pexider equations and their Hyers Ulam stability problems in the spaces of Schwartz distributions. First, reducing the given distribution version of functional equations to differential equations we find their solutions. Secondly, using approximate identities we prove the Hyers Ulam stability of the equations.

关键词： Pompeiu equations Pexider equations distributions Hyers Ulam stability

A weak form of beyond endoscopic decomposition for the stable trace formula of odd orthogonal groups

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Science China Mathematics 2018年第6期61卷 993-1012页

作者： chung Pang Mok Department of Mathematics Purdue University

We show that the cuspidal component of the stable trace formula of a split special odd orthogonal group over a number field, satisfies a weak form of beyond endoscopic decomposition. We also study the r-stable trace formula, when r is the standard or the second fundamental representation of the dual group, and show that they satisfy a similar kind of beyond endoscopic decomposition. The results are consequences of Arthur's works(2013) on endoscopic classification of automorphic representations, together with known results concerning a class of Langlands L-functions for special odd orthogonal groups.

关键词： cuspidal component stable trace formula beyond endoscopic decomposition r-stable trace formula

Stability of a Generalized Quadratic Functional Equation in Schwartz Distributions

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Acta Mathematica Sinica,English Series 2009年第9期25卷 1459-1468页

作者： Jae-Young chung Department of Mathematics Kunsan National University Kunsan 573-701 Republic of Korea

We consider the Hyers-Ulam stability problem of the generalized quadratic functional equationuoA＋voB-2woP1 - 2ko P2 =0, which is a distributional version of the classical generalized quadratic functional equation f（... 详细信息

关键词： Hyers-Ulam stability generalized quadratic functional equation distribution heat kernel

Morphological variability and genetic diversity in five species of Skeletonema(Bacillariophyta)

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Progress in Natural Science:Materials International 2008年第11期18卷 1345-1355页

作者： Ho Kin-chung School of Science & Technology The Open University of Hong Kong

Twelve strains of Skeletonema from Chinese coastal waters and another strain from the West Sea of Korea were examined using light microscopy(LM),scanning and transmission electron microscopy(SEM,TEM),and small subunit(SSU)rDNA sequence *** identified four species of Skeletonema:*** Sarno et Zingone,***(***)Bethge,*** Sarno et Kooistra,***- icum Cleve,as well as a Skeletonema-like *** are the first records of ***,*** and *** in *** Skeletonema-like species,MMDL5067,was isolated from the estuary of the Changjiang *** morphologic and phylogenetic char- acteristics of this species are not correspond to those of any previously published Skeletonema *** intercalary fultoportula pro- cesses(IFPPs)has long open tubes,and the intercalary rimoportula process(IRP)is short and located inside the rim of the IFPPs. Phylogenetic analysis revealed that MMDL5630 clustered with *** in the NJ and MP trees,but its IRPs differed from those of previously described specimens of *** IRP is partially open,with an elongated opening at the base of the tube,and is longer than the *** specimens of *** and *** also have longer tubular IRPs than the *** to pre- viously described specimens of *** and ***,these two specimens we identified have shorter *** results reflect the ambiguity and diversity of Skeletonema *** are also significant for the future identification and management of red tides caused by Skeletonema in the seas around China.

关键词： Morphological variability Genetic diversity Skeletonema SSU rDNA

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原因知觉量表在香港中学生人群中的检验

中国运动医学杂志 2014年第7期33卷 713-720页

作者：钟伯光刘靖东张春青香港浸会大学体育系

本研究的目的是在香港中学生人群中检验中文版本《原因知觉量表》(perceived locus of causality scale)在体育课中应用的相关心理测量学属性。两组香港中学生(样本1为346人,样本2为332人)被邀请完成原因知觉量表。来自两个样本的验证... 详细信息

本研究的目的是在香港中学生人群中检验中文版本《原因知觉量表》(perceived locus of causality scale)在体育课中应用的相关心理测量学属性。两组香港中学生(样本1为346人,样本2为332人)被邀请完成原因知觉量表。来自两个样本的验证性因素分析结果支持原因知觉量表的五因素结构。条目7(外部调节)和条目3(内摄调节)均表现出跨因素以及与其他条目显著相关的现象。因此,删除条目7和条目3显著改善模型拟合情况。区分效度分析发现,认同调节和内部动机相关过高,可能存在无法区分情况。研究者进一步对五因素模型和四因素模型(将认同调节因素和内部动机因素合为一个因素)进行比较发现,四因素模型并不优于五因素模型。虽然两维度存在高相关,但五因素模型予以保留。15条目五因素原因知觉量表各分量表内部一致性信度,除内摄调节因素外均大于0.70。同时,恒等性分析结果表明,15条目五因素模型具有跨性别和跨组别的测量恒等性。潜变量平均数差异检验结果表明,来自两个样本的中学生在五个因素上得分均无显著差异;但女生在无动机、外部调节和内摄调节三个因素上的得分显著低于男生。本研究结果为原因知觉量表的信、效度提供了初步支持,该量表可以在香港中学生体育课情境中使用。但需要注意的是,认同调节和内部动机两个分量表的区别不明显,未来研究可进一步对这两个分量表进行调整及修订。

关键词：动机自我决定理论体育课信度效度