An intelligent method to design die profile for rubber forming of complex curved flange part

Ling‑Yun Zhang,Shuai Zhou,Tian‑Zhang Zhao,Yi‑Pan Zeng 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.1

Rubber forming is an important forming process for the manufacture of aircraft sheet metal parts. The springback is one of the main defects in rubber forming. Classical springback compensation by displacement adjustment method using finite simulation is not satisfactory. In this research, the algorithms of compensating the arc and flange surface of complex curved flange with correction formula are proposed by experiment. The correction formula was developed based on the CATIA V5 R19 using Component Application Architecture. Compensate profile is presented including surface pick up, line pick up, division, compensation, extending, and trimming. The die profile of part with complex curved flanges in aircraft could be designed rapidly. It was found that the forming pressure has a little effect on the springback. This is within the tolerance limits of the part. The results reveal the method can achieve the industrial part precisely. The method is demonstrated on an aircraft wing rib part.

Next-generation sequencing for the genetic characterization of Maedi/Visna virus isolated from the northwest of China

Ling Zhao,Liang Zhang,Xiaona Shi,Xujie Duan,Huiping Li,Shuying Liu 대한수의학회 2021 Journal of Veterinary Science Vol.22 No.6

Background: Maedi/Visna virus (MVV) is a contagious viral pathogen that causes considerable economic losses to the sheep industry worldwide. Objectives: In China, MVV has been detected in several regions, but its molecular characteristics and genetic variations were not thoroughly investigated. Methods: Therefore, in this study, we conducted next-generation sequencing on an MVV strain obtained from northwest China to reveal its genetic evolution via phylogenetic analysis. Results: A MVV strain obtained from Inner Mongolia (NM) of China was identified. Sequence analysis indicated that its whole-genome length is 9193 bp. Homology comparison of nucleotides between the NM strain and reference strains showed that the sequence homology of gag and env were 77.1%–86.8% and 67.7%–75.5%, respectively. Phylogenetic analysis revealed that the NM strain was closely related to the reference strains isolated from America, which belong to the A2 type. Notably, there were 5 amino acid insertions in variable region 4 and a highly variable motif at the C-terminal of the surface glycoprotein (SU5). Conclusions: The present study is the first to show the whole-genome sequence of an MVV obtained from China. The detailed analyses provide essential information for understanding the genetic characteristics of MVV, and the results enrich the MVV library.

Networked Control for Delta Operator Systems Subject to Actuator Saturation

Ling Zhao,Zhiwei Li,Hongjiu Yang,Zhixin Liu 제어·로봇·시스템학회 2014 International Journal of Control, Automation, and Vol.12 No.6

In this paper, the problems of networked control for delta operator systems with actuator saturation are considered. Ellipsoids are used to estimate the domain of attraction for the networked control systems with actuator saturation. A condition for the networked control system is derived in terms of an auxiliary feedback matrix for determining if a given ellipsoid is contractive invariant. Discussions on the networked control systems performance optimization on expansion of the domain of attraction are presented. A numerical example on one-link PMW-controlled joint driven by pneumatic muscles is given to illustrate the effectiveness of the developed techniques.

Integral Sliding Mode Control of a Bilateral Teleoperation System based on Extended State Observers

Ling Zhao,Hao Zhang,Yana Yang,Hongjiu Yang 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.5

A novel control scheme has been proposed to solve the synchronization control problem for a nonlinearbilateral teleoperation system with time delays in this paper. An extended state observer is introduced to deal withthe lumped system uncertainties. Both fast convergence rate and high convergence precision are guaranteed viadesigning an integral sliding mode controller. Some general Lyapunov stability criteria are given for the nonlinearbilateral teleoperation system with time delays. Lastly, two Phantom Premium 1.5 HF robot manipulators are usedin the experiments to demonstrate the effectiveness of the developed techniques in this paper.

Adsorption performance of SO2 over ZnAl2O4 nanospheres

Ling Zhao,Sining Bi,Jiasi Pei,Xinyong Li,Ruihong Yu,Ji Zhao,Christopher J. Martyniuk 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.41 No.-

A type of uniform ZnAl2O4 nanospheres was selectively synthesized via a facile solvothermalmethod andtheir size was controlled to be 320–450 nm in diameter. It exhibits excellent SO2 adsorption capacity. Both physical structure and surface basicity were determined to play important roles in SO2 adsorptionprocess. In situ FTIR investigation revealed that adsorbed SO2 molecules formed surface bisulfite, sulfite,and bidentate binuclear sulfate. The CO2-TPD results revealed the SO2 adsorption capacity of thecatalysts correlated closely with their basicity sites. The mechanisms for SO2 adsorption andtransformation have been discussed in detail.

High Expression of Bcl-2 Protein Predicts Favorable Outcome in Non-small Cell Lung Cancer: Evidence from a Systematic Review and Meta-analysis

Zhao, Xian-Da,He, Yu-Yu,Gao, Jun,Zhao, Chen,Zhang, Ling-Lin,Tian, Jing-Yuan,Chen, Hong-Lei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.20

Background: The prognostic value of Bcl-2 protein expression in non-small cell lung cancer (NSCLC) is under debate. We therefore systematically reviewed the evidence for Bcl-2 protein effects on NSCLC survival to elucidate this issue. Materials and Methods: An electronic search in Pubmed and Embase complemented by manual searches in article references were conducted to identify eligible studies to evaluate the association between Bcl-2 protein expression and overall survival (OS) as well as disease free survival (DFS) of NSCLC patients. Combined hazard ratios (HRs) with corresponding 95% confidence intervals (95%CIs) were pooled using the random-effects model. Results: A total of 50 trials (including 52 cohorts) encompassing 7,765 patients were pooled in the meta-analysis regarding Bcl-2 expression and OS of NSCLC patients. High expression of Bcl-2 protein had a favorable impact (HR=0.76, 95%CI=0.67-0.86). In the group of Bcl-2 expression and DFS, 11 studies including 2,634 patients were included. The synthesized result indicated high expression of Bcl-2 protein might predict good DFS (HR=0.85, 95%CI=0.75-0.95). Conclusions: Our present meta-analysis demonstrated favorable prognostic values of Bcl-2 expression in patients with NSCLC. Further prospective trails are welcomed to validate the utility of assessing Bcl-2 in NSCLC patient management.

Recent advances in heighten sulfur resistance of SCR catalysts: A review

Ling Zhao,Yu Zhang,Mengdi Kang 대한환경공학회 2022 Environmental Engineering Research Vol.27 No.1

NOx removal by selective catalytic reduction (SCR) technology is a research hotspot in the field of environmental catalysis, and this method is dominated by catalysts. However, denitrification catalyst is easy to be polluted by the presence of SO₂, which seriously restricts its practical industrial application. This review focuses on the latest domestic and foreign research results and advancement in improving sulfur resistance of deNOx catalysts, reveals the sulfur poisoning mechanism and regeneration process, as well as introduces the positive role of quantum chemistry in the field of sulfur resistance. In view of the questions set forth in this review, the future development direction of deNOx catalysts is prospected, which provides valuable scientific guidance for the design and development of efficient and practical sulfur resistant deNOx catalysts.

Member capacity of columns with semi-rigid end conditions in Oktalok space frames

Zhao, Xiao-Ling,Lim, Peter,Joseph, Paul,Pi, Yong-Lin Techno-Press 2000 Structural Engineering and Mechanics, An Int'l Jou Vol.10 No.1

The Oktalok nodal connection system is an aesthetic and efficient system. It has been widely used throughout Australia. The paper will briefly introduce the concept and application of the Oktalok nodal system. The existing design method is based on the assumption that the joints are pin-ended, i.e., the rotational stiffness of the joints is zero. However the ultimate capacity of the frame may increase significantly depending on the rotational stiffness of the joints. Stiffness tests and finite element simulations were carried out to determine the rotational stiffness of the Oktalok joints. Column buckling tests and non-linear finite element analyses were performed to determine the member capacity of columns with semi-rigid end conditions. A simple formulae for the effective length factor of column buckling is derived based on the above experimental and theoretical investigations.

A Multi-center Survey of HPV Knowledge and Attitudes Toward HPV Vaccination among Women, Government Officials, and Medical Personnel in China

Zhao, Fang-Hui,Tiggelaar, Sarah M.,Hu, Shang-Ying,Zhao, Na,Hong, Ying,Niyazi, Mayinuer,Gao, Xiao-Hong,Ju, Li-Rong,Zhang, Li-Qin,Feng, Xiang-Xian,Duan, Xian-Zhi,Song, Xiu-Ling,Wang, Jing,Yang, Yun,Li, Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Objectives: To assess knowledge of HPV and attitudes towards HPV vaccination among the general female population, government officials, and healthcare providers in China to assist the development of an effective national HPV vaccination program. Methods: A cross-sectional epidemiologic survey was conducted across 21 urban and rural sites in China using a short questionnaire. 763 government officials, 760 healthcare providers, and 11,681 women aged 15-59 years were included in the final analysis. Data were analyzed using standard descriptive statistics and logistic regression. Results: Knowledge of HPV among the general female population was low; only 24% had heard of HPV. Less than 20% of healthcare providers recognized sexually na$\ddot{i}$ve women as the most appropriate population for HPV vaccination. There was high acceptance of the HPV vaccine for all categories of respondents. Only 6% of women were willing to pay more than US $300 for the vaccine. Conclusions: Aggressive education is necessary to increase knowledge of HPV and its vaccine. Further proof of vaccine safety and efficacy and government subsidies combined with increased awareness could facilitate development and implementation of HPV vaccination in China.

Polymer Blends Used to Prepare Nifedipine Loaded Hollow Microspheres for a Floating-type Oral Drug Delivery System: In Vitro Evaluation

Ling Zhao,Yu Yu,Wen-wu Zheng,Yu-meng Wei 대한약학회 2010 Archives of Pharmacal Research Vol.33 No.3

The aim of this study was to investigate whether hollow microspheres prepared from polymer blends of polyvinyl pyrrolidone (PVP) and ethyl cellulose (EC) could improve the vitro release behavior of the poorly water-soluble drug nifedipine. Hollow microspheres containing nifedipine were prepared by a solvent diffusion-evaporation method using various ratios of PVP and EC codissolved with drug in ethanol/ether (5:1, v/v). The hollow microspheres could float in release medium for more than 24 h, and floating capacities were not be influenced by mixing PVP. In vitro release profiles of hollow microspheres prepared using EC along showed an initial burst release to some extent, and the cumulative release percentage was less than 55% after 24 h. But, not only the slope but also the shape of the release curves was affected by using mixture of PVP and EC. What’s more important, when the ratio (PVP/EC) increased to 1.5:8.5, the cumulative release percentage could be increased to 95.8%. Furthermore, the release rate of microspheres showed a zero order approximate dynamic model and could be expressed by the following equation: Q=3.78t+8.52 (r=0.990). Consequently, hollow microspheres prepared using polymer blends of PVP and EC (1.5:8.5, w/w) could be suitable for floating-type controlled-release delivery systems for the oral administration of nifedipine.