Principal axes of M-DOF structures Part I:Static loading

This paper is the first in a two-part series that discusses the principal axes of M-DOF structures subjected to static and dynamic loads. The primary purpose of this series is to understand the magnitude of the dynamic response of structures to enable better design of structures and control modification devices/systems. Under idealized design conditions, the structural responses are obtained by using single direction input ground motions in the direction of the intended control devices/systems, and by assuming that the responses of the structure is decoupleable in three mutually perpendicular directions. This standard practice has been applied to both new and retrofitted structures using various seismic protective systems. Very limited information is available on the effects of neglecting the impact of directional couplings (cross effects - of which torsion is a component) of the dynamic response of structures. In order to quantify such effects, it is necessary to examine the principal axes of structures under both static and dynamic loading. This first paper deals with quantitative definitions of principal axes and “cross effects” of three-dimensional structures under static load by using linear algebra. It shows theoretically that, for three-dimensional structures, such principal axes rarely exist. Under static loading conditions, the cross effect is typically small and negligible from the viewpoint of engineering applications. However, it provides the theoretical base for subsequent quantification of the response couplings under dynamic loads, which is reported in part II of this series.

Principal axes of M-DOF structures PartⅡ:Dynamic loading

This paper is the second in a two-part series that discusses the principal axes of M-DOF structures subjected to static and dynamic loads.The primary purpose of this series is to understand the magnitude of the dynamie response of structures to enable better design of structures and response modification devices/systems.Under idealized design condi- tions,the structural responses are obtained by using single directinn input ground motions in the direction of the intended response modification devices/systems,and by assuming that the responses of the structure is deconpleable in three mutual- ly perpendicular directions.This standard practice has been applied to both new and retrofitted structures using various seis- mic protective systems.Very limited information is available on the effects of neglecting the impact of directional couplings (cross effects of which torsion is a component)of the dynamic response of structures.In order to quantify such effects,it is necessary to examine the principal axes of structures under both static and dynamic loading.In this twn-part series,the first paper is concerned with static loading,which provides definitions and fundamental formulations,with the conclusion that cross effects of a statically loaded M-DOF structure resulting from the lack of principal axes are of insignificant magnitude. However,under dynamic or earthquake loading,a relatively small amount of energy transferred across perpendicular direc- tions is accumulated,which may result in significant enlargement of the structural response.This paper deals with a formu- lation to define the principal axes of M-DOF structures under dynamic loading and develops quantitative measures to identify cross effects resuhing from the non-existence of principal axes.

A local and global statistics pattern analysis method and its application to process fault identification

Traditional principal component analysis （PCA） is a second-order method and lacks the ability to provide higherorder representations for data variables. Recently, a statistics pattern analysis （SPA） framework has been incorporated into PCA model to make full use of various statistics of data variables effectively. However, these methods omit the local information, which is also important for process monitoring and fault diagnosis. In this paper, a local and global statistics pattern analysis （LGSPA） method, which integrates SPA framework and locality pre- serving projections within the PCK is proposed to utilize various statistics and preserve both local and global in- formation in the observed data. For the purpose of fault detection, two monitoring indices are constructed based on the LGSPA model. In order to identify fault variables, an improved reconstruction based contribution （IRBC） plot based on LGSPA model is proposed to locate fault variables. The RBC of various statistics of original process variables to the monitoring indices is calculated with the proposed RBC method. Based on the calculated RBC of process variables＇ statistics, a new contribution of process variables is built to locate fault variables. The simula- tion results on a simple six-variable system and a continuous stirred tank reactor system demonstrate that the proposed fault diagnosis method can effectively detect fault and distinguish the fault variables from normal variables.

Arrangement for Capital Structure in the Framework of Corporate Governance

Using the method of principal component analysis, the paper conducts a systematic study on the issue of how corporate governance influences capital structure. The study manifests the results that the proportion of circulation shares, the ability that other big shareholders contend with the first biggest shareholder, the proportion of corporation-owned shares, and the frequency of directorate meetings all have a positive relationship with the liability level. Meanwhile, the concentration degree of owners＇ equity, the proportion of state-owned shares, the phenomenon that one person serves as both chairman of directorate and general manager, and the intensity of competition in product market are all negatively related to the level of debt. Finally, the scale of directorate, the proportion of independent directors as well as the percentage of management-owned shares have no significant relationship with the capital structure. The statistic analysis also shows that the proportion of independent directors of some Chinese listed companies does not meet the regulation of the CSRC. In addition, the paper tests the impacts of corporate operating characteristics on capital structure.

Comparison between SSR and SNP systems of genetic diversity analysis in Brassica napus L.

Simple sequence repeat(SSR) capillary electrophoresis and single nucleotide polymorphism(SNP) array are widely used tools for investigating genetic diversity. However, efficiency between SSR and SNP on rapeseed genetic diversity has not been systematically assessed yet. In this study, both SSR and SNP were used on 446 worldwide B. napus germplasm lines. Data shows that 65 pairs of primers(70 SSRs) and 250 SNPs were necessary to identify the similar accessions. Furthermore, no significant differences were found between 2 systems on basic statistics, population structures, principal components and kinship parameters. In general, either SSR or SNP is efficient for genetic diversity estimation. However, our data revealed the fact that SNP array system shows slightly more accuracy than SSR system on ecotype groups division.