Single probe shear scanning method for on-machine measurement of an optical profile.

This study presents a new (to the best of our knowledge) error separation method with a single displacement probe, named as single probe shear scanning (SPSS) method, for the on-machine optical profile measurement to overcome the problems of the existing multiprobe method like the large deviation of probe spacing and the probes' performance difference. The confocal sensor with superior dynamic range, high lateral resolution, and large measurement angle to surface is applied in this study to fulfill the measurement of the optical aspheric surface. The single probe measurement system, in which the probe fixed on a flexure hinge is driven straight within a millimeter-level travel range, is established to realize the function of the multiprobe. For the established system, a new exact profile reconstruction algorithm is built to eliminate the influences of straightness errors of the scanning stage and the systemic errors of shear stage, and to reduce the effect of the sensor drift. The reconstruction algorithms by difference measurement with two shears are studied to build the bidirectional segment stitching reconstruction method, which reduces the error accumulation and improves the reconstruction accuracy under the condition of measuring errors. A profile reconstruction method with three shears measurement is proposed to make a further improvement on the reconstruction accuracy. The proposed reconstruction method with three shears measurement is successfully employed for the on-machine measurement of an aspheric surface profile, and the evaluation results agree well with those from the Taylor profiler.

Governance and competitiveness evaluation of China's financial asset management corporations.

With the development of non-performing assets market and the requirement of maintaining national financial security and stability, asset management corporations (AMC) have set up in recent years, facing the dilemma of governance reform and competitiveness improvement. This paper puts forward the Governance-Performance-Competitiveness theory of asset management corporations, and constructs the comprehensive competitiveness evaluation index system of based on internal and external governance mechanisms, and studies the factors and degrees of internal and external governance affecting competitiveness by combining principal component analysis method and grey correlation analysis method. The empirical results show that the asset scale and profitability of asset management corporations directly determine their competitiveness level to a large extent, and the correlation between external governance mechanism and competitiveness is stronger than that of internal governance mechanism. Clustering and grouping are conducted based on the size of competitiveness, and China's local asset management corporation system presents a diamond structure. China's local financial asset management corporations should strengthen the top-level design of internal governance, attach importance to external governance, expand and strengthen the asset scale, and carry out full-chains business while implementing a differentiated development model to achieve sustainable development when adhering to the principal business of non-performing assets.