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Developing accurate and efficient measurement systems for blade profiles has always been a vital issue in blade manufacturing. Nowadays, optical-based systems for measuring blade profiles have attracted significant interest due to their high efficiency and flexibility. However, as key steps in optical measurement of blades, system calibration and establishment of measurement datum are normally accomplished based on calibration objects, which may introduce uncertainty and affect the accuracy of the measurement. In this article, we propose a novel method for blade-profile measurement based on blade self-features. A measurement system based on a four-axis platform and laser scanning sensor (LSS) is developed. A calibration method based on the blade datum plane feature is introduced to eliminate the pose error of the system without using additional calibration objects. A feature-matching algorithm based on the covariance matrix of the blade local leading-edge feature is further proposed to establish the measurement datum. The proposed method requires smaller system-motion space and fewer LSS viewpoints, which would improve the efficiency and flexibility of the measurement system. Furthermore, less error accumulation can be achieved using our method, thus, resulting in higher measurement accuracy. The experimental results reveal the feasibility and good practical application prospect of this method.

Supplemental Material for Association between BPA exposure and thyroid dysfunction in adults: A systematic review and meta-analysis by Shumeng Yuan, Xingde Du, Haohao Liu, Xing Guo, Bingyu Zhang, Yongshui Wang, Bingqian Wang, Huizhen Zhang, and Hongxiang Guo in Toxicology and Industrial Health.

Nematic liquid crystals are promising materials for microwave communication owing to their continuous tunability as dielectrics and wide frequency range selection. However,conventional liquid crystals exhibit large dielectric loss and high freezing point, hindering their research and application in microwave communication. in this paper,14 novel liquid crystal polyphenylene compounds with lateral methyl substitute were synthesised. Their structures were characterized by IR, NMR,MS and the elemental analyses. Their mesogenic properties were analyzed by POM and DSC. The dielectric properties in microwave frequencies(10-35 GHz)of eight target compounds (6a,7b,8a~8e) with LC matrix were obtained by extrapolation and perturbation techniques. The results show that i. fluorinated polyphenylene compounds with lateral methyl generally exhibited low melting points (���75��C), ii. compounds with isothiocyanate group yielded high birefringence 0.385-0.441, iii. compounds based on quaterphenyl displayed a wide temperature range of nematic phase, and iv. the maximum dielectric loss of compounds 6e,8c,8e are less than 6.51��10-3,which are better than those of using fluorine replace the methyl group derivative. Therefore, the proposed approach can effectively reduce dielectric loss,reduce the melting temperature, improve the dielectric properties of liquid crystal materials for microwave communication.

The compute-storage framework is responsible for data storage and processing, and acts as the digital chassis of all upper-level businesses. The performance of the framework affects the business's processing throughput, latency, jitter, and etc., and also determines the theoretical performance upper bound that the business can achieve. In financial applications, the compute-storage framework must have high reliability and high throughput, but with low latency as well as low jitter characteristics. For some scenarios such as hot-spot account update, the performance of the compute-storage framework even surfaces to become a server performance bottleneck of the whole business system. In this paper, we study the hot-spot account issue faced by Alipay and present our exciting solution to this problem by developing a new compute-storage system, called Maxwell. Maxwell is a distributed compute-storage system with integrated hardware and software optimizations. Maxwell does not rely on any specific hardware (e.g. GPUs or FPGAs). Instead, it takes deep advantage of computer components' characteristics, such as disk, network, operating system and CPU, and aims to emit the ultimate performance of both hardware and software. In comparison with the existing hot-spot account updating solutions deployed online, Maxwell achieves three orders of magnitude performance improvement for end-to-end evaluation. Meanwhile, Maxwell also demonstrates remarkable performance gains in other related businesses of Ant Group.

Graphene is widely used in numerous scientific fields including physics, chemistry and materials science due to its exceptional electrical, thermal, optical and mechanical properties. However, the poor solubility/dispersibility strongly limits the practical applications of graphene. In this work, hydroxypropyl hydrazine (HPH) was synthesized to reduce graphene oxide (GO) under mild conditions. The as-produced graphene sheets with a 3D-porous structure show admirable dispersion stability in N,N-dimethylacetamide (DMAc) and the graphene sheets are more effective absorbents for Cu2+ removal than those reduced by hydrazine hydrate. A mechanism for removal of epoxides and carboxides from GO by HPH has been proposed. This one-step reducing and dispersing process of GO is more efficient, environmentally benign and safer for the bulk-scale production of 3D porous graphene.