A High-Precision Form-Free Metrological Method of Aeroengine Blades

Zhao-Yao Shi,Xue-Zhe Li,Yu-Kun Li,Jia-Chun Lin 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.12

In order to solve the problems in existing methods for blade profile metrology, such as low accuracy and efficiency, poor flexibility, various constraints, a high-precision form-free method for blade profile metrology is proposed. In the paper, the operational principle, key technologies and evaluation methodology are analyzed in detail. A high-precision method for blade profile metrology based on the concept of “Synchronization of Planning and Measurement” is proposed to solve three key problems for blade metrology synchronously: theoretical data acquisition, path planning and sampling strategy analysis, and profile measurement. A form-free evaluation methodology for blade profile based on parametric modeling is also discussed. The results show that the metrology and evaluation for blade profile are executed automatically without theoretical model data, thus improving the efficiency and flexibility greatly. In addition, all the measurements are completed in the positions near the reference distance of the sensor, thus the depth of measurement approaches 0 mm and the measurement error is no more than 10 μm. The method proposed in the paper is a form-free method with a high precision and has a good application prospect in the field of free-form surface measurement.

A novel pathogenic deletion in ISPD causes Walker-Warburg syndrome in a Chinese family

Shi Yuting,Fu Yimei,Tao Zhouteng,Yong Wenjing,Peng Huirong,Jian Wenyang,Chen Gang,Guo Manhui,Zhao Yanhua,Yao Ruojin,Guo Dewei 한국유전학회 2023 Genes & Genomics Vol.45 No.3

Background Walker-Warburg syndrome (WWS) is a genetically heterogeneous disease that often presents with complex brain and eye malformations and congenital muscular dystrophy. Mutations of the ISPD gene have been identified as one of the most frequent causes of WWS. Objective The current study aimed to identify the cause of severe congenital hydrocephalus and brain dysplasia in our subject. Methods Genomic DNA was extracted from the fetus's umbilical cord blood and peripheral venous blood of the parents. The genetic analysis included whole-exome sequencing and qPCR. Additionally, in silico analysis and cellular experiments were performed. Results We identified a novel homozygous deletion of exons 7 to 9 in the ISPD gene of the fetus with WWS. In silico analysis revealed a defective domain structure in the C-terminus domain of the ISPD. Analysis of the electrostatic potential energy showed the formation of a new binding pocket formation on the surface of the mutant ISPD gene (ISPD-del ex7-9). Cellular study of the mutant ISPD revealed a significant change in its cellular localization, with the ISPD-del ex7-9 protein translocating from the cytoplasm to the nucleus compared to wild-type ISPD, which is mostly present in the cytoplasm. Conclusion The present study expands the mutational spectrum of WWS caused by ISPD mutations. Importantly, our work suggests that whole-exome sequencing could be considered as a diagnostic option for fetuses with congenital hydrocephalus and brain malformations when karyotype or chromosomal microarray analysis fails to provide a definitive diagnosis.

The relationship between eccentric structure and super-lift device of all-terrain crane based on the overall stability

Yao Fenglin,Meng Wenjun,Zhao Jie,Shi Guoshan,Bai Yanqiang,Li Hui,Cui Yaodong 대한기계학회 2020 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.34 No.6

When the large all-terrain crane operated under ultra-high hoisting height, the stability of boom system became the key factor of the lifting capacity. The installation of eccentric structure and super-lift device could help to improve the stability of boom system. In order to achieve the best effect of growth, it was important to study the relationship between eccentric structure and super-lift device. The eigenvalue buckling analysis and geometric nonlinear buckling analysis were carried out by ANSYS for the combined boom system of 500 t all-terrain crane with tower jib when lifting load, dead weight, offset load, wind load and lifting rope force were considered. And then the influence rule of the combined relationship between the strut length, opening angle, amplitude variation angle of the eccentric structure and the strut length, opening angle, amplitude variation angle of the super-lift device on the overall stability of combined boom system was analyzed to obtain the optimum parameter combination of eccentric structure and super-lift device, which provides reference for engineering practice.

Equivalent static wind loads analysis of tall television towers considering terrain factors of hilltops based on force measurement experiment

Shi-Tang Ke,Hao Wang,Yao-Jun Ge,Lin Zhao,Shuyang Cao 국제구조공학회 2017 Structural Engineering and Mechanics, An Int'l Jou Vol.63 No.4

Wind field in mountainous regions demonstrates unique distribution characteristic as compared with the wind field of the flat area, wind load and wind effect are the key considerations in structural design of television towers situated in mountainous regions. The television tower to be constructed is located at the top of Xiushan Mountain in Nanjing, China. In order to investigate the impact of terrain factors of hilltops on wind loads, firstly a wind tunnel test was performed for the mountainous area within 800m from the television tower. Then the tower basal forces such as bending moments and shear strength were obtained based on high frequency force balance (HFFB) test. Based on the experiments, the improved method for determining the load combinations was applied to extract the response distribution patterns of foundation internal force and peak acceleration of the tower top, then the equivalent static wind loads were computed under different wind angles, load conditions and equivalent goals. The impact of terrain factors, damping ratio and equivalent goals on the wind load distribution of a television tower was discussed. Finally the equivalent static wind loads of the television tower under the 5 most adverse wind angles and 5 most adverse load conditions were computed. The experimental method, computations and research findings provide important references for the anti-wind design of high-rise structure built on hilltops.

Design and Implementation of a Universal System Control Strategy Applicable to VSC-HVDC Systems

Zhao, Yue,Shi, Li-bao,Ni, Yi-xin,Xu, Zheng,Yao, Liang-zhong The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1

This paper proposes a universal system control strategy for voltage source converter (VSC) based high voltage direct current (HVDC) systems. The framework of the designed control strategy consists of five layer structures considering the topology and control characteristics of the VSC-HVDC system. The control commands sent from the topmost layer can be transmitted to the next layer based on the existing communication system. When the commands are sent to each substation, the following transmission of commands between the four lower layers are realized using the internal communication system while ignoring the communication delay. This hierarchical control strategy can be easily applied to any VSC-HVDC system with any topology. Furthermore, an integrated controller for each converter is designed and implemented considering all of the possible operating states. The modular-designed integrated controller makes it quite easy to extend its operating states if necessary, and it is available for any kind of VSC. A detailed model of a VSC-HVDC system containing a DC hub is built in the PSCAD/EMTDC environment. Simulation results based on three operating conditions (the start-up process, the voltage margin control method and the master-slave control method) demonstrate the flexibility and validity of the proposed control strategy.

8q24 rs4242382 Polymorphism is a Risk Factor for Prostate Cancer among Multi-Ethnic Populations: Evidence from Clinical Detection in China and a Meta-analysis

Zhao, Cheng-Xiao,Liu, Ming,Xu, Yong,Yang, Kuo,Wei, Dong,Shi, Xiao-Hong,Yang, Fan,Zhang, Yao-Guang,Wang, Xin,Liang, Si-Ying,Zhao, Fan,Zhang, Yu-Rong,Wang, Na-Na,Chen, Xin,Sun, Liang,Zhu, Xiao-Quan,Yuan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

Background: Evidence supporting an association between the 8q24 rs4242382-A polymorphism and prostate cancer (PCa) risk has been reported in North American and Europe populations, though data from Asian populations remain limited. We therefore investigated this association by clinical detection in China, and meta-analysis in Asian, Caucasian and African-American populations. Materials and Methods: Blood samples and clinical information were collected from ethnically Chinese men from Northern China with histologically-confirmed PCa (n=335) and from age-matched normal controls (n=347). The 8q24 (rs4242382) gene polymorphism was genotyped by polymerase chain reaction-high-resolution melting analysis. We initially analyzed the associations between the risk allele and PCa and clinical covariates. A meta-analysis was then performed using genotyping data from a total of 1,793 PCa cases and 1,864 controls from our study and previously published studies in American and European populations, to determine the association between PCa and risk genotype. Results: The incidence of the risk allele was higher in PCa cases than controls (0.222 vs 0.140, $P=7.3{\times}10^{-5}$), suggesting that the 8q24 rs4242382-A polymorphism was associated with PCa risk in Chinese men. The genotypes in subjects were in accordance with a dominant genetic model (ORadj=2.03, 95%CI: 1.42-2.91, $Padj=1.1{\times}10^{-4}$). Presence of the risk allele rs4242382-A at 8q24 was also associated with clinical covariates including age at diagnosis ${\geq}65$ years, prostate specific antigen >10 ng/ml, Gleason score <8, tumor stage and aggressive PCa, compared with the non-risk genotype ($P=4.6{\times}10^{-5}-3.0{\times}10^{-2}$). Meta-analysis confirmed the association between 8q24 rs4242382-A polymorphism and PCa risk (OR=1.62, 95%CI: 1.39-1.88, $P=1.0{\times}10^{-5}$) across Asian, Caucasian and African American populations. Conclusions: The replicated data suggest that the 8q24 rs4242382-A variation might be associated with increased PCa susceptibility in Asian, Caucasian and African American populations. These results imply that this polymorphism may be a useful risk biomarker for PCa in multi-ethnic populations.

Highly Ordered Mesoporous Crystalline MoSe₂ Material with Efficient Visible‐Light‐Driven Photocatalytic Activity and Enhanced Lithium Storage Performance

Shi, Yifeng,Hua, Chunxiu,Li, Bin,Fang, Xiangpeng,Yao, Chaohua,Zhang, Yichi,Hu, Yong‐,Sheng,Wang, Zhaoxiang,Chen, Liquan,Zhao, Dongyuan,Stucky, Galen D. WILEY‐VCH Verlag 2013 Advanced functional materials Vol.23 No.14

<P><B>Abstract</B></P><P>Highly ordered mesoporous crystalline MoSe<SUB>2</SUB> is synthesized using mesoporous silica SBA‐15 as a hard template via a nanocasting strategy. Selenium powder and phosphomolybdic acid (H<SUB>3</SUB>PMo<SUB>12</SUB>O<SUB>40</SUB>) are used as Se and Mo sources, respectively. The obtained products have a highly ordered hexagonal mesostructure and a rod‐like particle morphology, analogous to the mother template SBA‐15. The UV‐vis‐NIR spectrum of the material shows a strong light absorption throughout the entire visible wavelength region. The direct bandgap is estimated to be 1.37 eV. The high surface area MoSe<SUB>2</SUB> mesostructure shows remarkable photocatalytic activity for the degradation of rhodamine B, a model organic dye, in aqueous solution under visible light irradiation. In addition, the synthesized mesoporous MoSe<SUB>2</SUB> possess a reversible lithium storage capacity of 630 mAh g<SUP>−1</SUP> for at least 35 cycles without any notable decrease. The rate performance of mesoporous MoSe<SUB>2</SUB> is much better than that of analogously synthesized mesoporous MoS<SUB>2</SUB>, making it a promising anode for the lithium ion battery.</P>

Anti-neuroinflammatory Effects of 12-Dehydrogingerdione in LPS-Activated Microglia through Inhibiting Akt/IKK/NF-κB Pathway and Activating Nrf-2/HO-1 Pathway

Dong Zhao,Ming-Yao Gu,Jiu Liang Xu,Li Jun Zhang,Shi Yong Ryu,양현옥 한국응용약물학회 2019 Biomolecules & Therapeutics(구 응용약물학회지) Vol.27 No.1

Ginger, one of worldwide consumed dietary spice, is not only famous as food supplements, but also believed to exert a variety of remarkable pharmacological activity as herbal remedies. In this study, a ginger constituent, 12-dehydrogingerdione (DHGD) was proven that has comparable anti-inflammatory activity with positive control 6-shogaol in inhibiting LPS-induced interleukin (IL)-6, tumor necrosis factor (TNF)-α, prostaglandin (PG) E2, nitric oxide (NO), inducible NO synthase (iNOS) and cyclooxygenase (COX)-2, without interfering with COX-1 in cultured microglial cells. Subsequent mechanistic studies indicate that 12-DHGD may inhibit neuro-inflammation through suppressing the LPS-activated Akt/IKK/NF-κB pathway. Furthermore, 12-DHGD markedly promoted the activation of NF-E2-related factor (Nrf)-2 and heme oxygenase (HO)-1, and we demonstrated that the involvement of HO-1 on the production of pro-inflammatory mediators such as NO and TNF-α by using a HO-1 inhibitor, Zinc protoporphyrin (Znpp). These results indicate that 12-DHGD may protect against neuro-inflammation by inhibiting Akt/IKK/IκB/NF-κB pathway and promoting Nrf-2/HO-1 pathway.

Buckling theoretical analysis on all-terrain crane telescopic boom with n-stepped sections

Fenglin Yao,Wenjun Meng,Jie Zhao,Zhanjiao She,Guoshan Shi,Haibo Liu 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.8

Differential equations for telescopic boom with n-stepped sections are established on the basis of continuous beam column theory. The recursive formula for the stability of n-stepped telescopic boom is deduced by mathematical induction. The Levenberg-Marquardt numerical optimization algorithm combined with mechanical features is used to solve the transcendental equation in the recursive formula and determine the equations when n is unknown. The length coefficients obtained using the presented methods are compared with those of the China national standard GB3811-2008 and those calculated by ANSYS 17.0. Results show that the accuracy of the LevenbergMarquardt algorithm is better than those of other algorithms. Moreover, the obtained length coefficients display a certain degree of nonlinearity. Therefore, linear interpolation is feasible in small-scale practical applications. The use of linear interpolation method leads to large error in the critical force in n-stepped section of all-terrain cranes.

Design and Implementation of a Universal System Control Strategy Applicable to VSC-HVDC Systems

Yue Zhao,Libao Shi,Yixin Ni,Zheng Xu,Liang-Zhong Yao 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1

This paper proposes a universal system control strategy for voltage source converter (VSC) based high voltage direct current (HVDC) systems. The framework of the designed control strategy consists of five layer structures considering the topology and control characteristics of the VSC-HVDC system. The control commands sent from the topmost layer can be transmitted to the next layer based on the existing communication system. When the commands are sent to each substation, the following transmission of commands between the four lower layers are realized using the internal communication system while ignoring the communication delay. This hierarchical control strategy can be easily applied to any VSC-HVDC system with any topology. Furthermore, an integrated controller for each converter is designed and implemented considering all of the possible operating states. The modular-designed integrated controller makes it quite easy to extend its operating states if necessary, and it is available for any kind of VSC. A detailed model of a VSC-HVDC system containing a DC hub is built in the PSCAD/EMTDC environment. Simulation results based on three operating conditions (the start-up process, the voltage margin control method and the master-slave control method) demonstrate the flexibility and validity of the proposed control strategy.