Dynamic analysis of cross shaft type universal joint with clearance

Jian-Wei Lu,Gong-Cheng Wang,Hao Chen,Alexander F. Vakakis,Lawrence A. Bergman 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.11

Cross shaft type universal joint is widely used in ground vehicles to transfer torque between two intersecting axes, and its transmission feature can make a great contribution to NVH performance of the vehicle. We looked at the assembling clearance at cross shaft neck, and presented a dynamic model of cross shaft type universal joint with clearance at cross shaft neck. Two-state model is applied to describe the contact force between the cross shaft and driving joint fork based on Hertz theorem, and lumped mass method is applied to build up the dynamic model of the universal joint. Based on this model, numerical analysis is carried out to discuss the transmission feature of the universal joint with clearance at cross shaft neck, and the influence of clearance on the dynamic behavior of the system is evaluated with numerical results based on time history, power spectrum, and phase portrait. The method and conclusions presented are helpful to improvement of the transmission feature of cross shaft type universal joint.

NUMERICAL STUDY ABOUT AIRCRAFT-SKIN INFRARED CHARACTERISTICS AND ITS SUPPRESSION EFFECTIVENESS

Jian-Wei Lu,Qiang Wang,Oh Joon Kwon 한국전산유체공학회 2010 한국전산유체공학회 학술대회논문집 Vol.2010 No.11

In supersonic cruise the temperature of aircraft skin arises higher than 300K due to aerodynamic heating. Then aircraft-skin infrared suppression of minimizing the radiation contrast of the aircraft skin from its background becomes a crucial survival technology. In the present study, a technique for the effectiveness evaluation of infrared suppression of aircraft skin is proposed. For this purpose, a synthetic model to simulate the overall numerical procedure has been developed. The thermal status on the aircraft skin was obtained by a computational fluid dynamics(CFD) method. Then, an infrared (IR) signature model for complex aircraft geometries was proposed with the reverse Monte Carlo(RMC) technique. The infrared contrast was adopted as the performance indicators for the evaluation of aircraft infrared suppression. The influence of aircraft skin radiation related factors, such as the aircraft-skin emissivity and the aircraft-skin temperature distribution, on the infrared contrast was also studied theoretically. The method has been applied to clarify the contribution of each aircraft components to the IR suppression of the overall infrared radiation. The results show that aircraft-skin temperature control and emissivity control are an effective approach to reduce the infranred radiation and to achieve lower detection. The results can be used as a practical guide line for designing future stealth aircrafts.

Influences of stochastic perturbation of parameters on dynamic behavior of gear system

Jian-Wei Lu,Fan-Ling Zeng,Jia-Yun Xin,En-Min Miao,Meng-Jun Liu 대한기계학회 2011 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.25 No.7

Gear systems are commonly used in vehicles, and the vibration of the gear system was paid more attention in recent years. In this paper,the dynamic behavior of gear system with stochastic perturbation of system parameters was analyzed. A stochastic nonlinear dynamic model of gear system, with consideration of the stochastic perturbation of system parameters, was established. The influences of stochastic perturbation of system parameters, such as excitation frequency, damping ratio, and backlash, on the dynamic behavior of the system were discussed. It was found that when the perturbation intensity is weak, the topological structure of the system solutions will not change, and there is no transition of the attractors. But if the perturbation intensity increases further, there will be transition between the attractors. In general, for single-DOF gear system, the multi-periodic attractor will jump to the quasi-period-1 attractor. But the quasiperiod-1 attractor will not jump to other attractors. If the perturbation intensity is considerable great, bi-directional transition will occur. Yet, the probability of transition from multi-periodic attractor to quasi-period-1 attractor is greater than the probability of transition from multi-periodic attractor to other attractors. Which provide theoretical basis for effective vibration control of gear system.

CircularRNA_104670 plays a critical role in intervertebral disc degeneration by functioning as a ceRNA

Jian Son,Hong-Li Wang,Ke-Han Song,Zhi-Wen Ding,Hai-Lian Wang,Xiao-Sheng Ma,Fei-Zhou Lu,Xin-Lei Xia,Ying-Wei Wang,Fei-Zou,Jian-Yuan Jiang 생화학분자생물학회 2018 Experimental and molecular medicine Vol.50 No.-

This study was carried out to explore the roles of circular RNAs (circRNAs) in nucleus pulposus (NP) tissues in intervertebral disc degeneration (IDD). Differentially expressed circRNAs in IDD and normal NP tissues were identified based on the results of microarray analysis. Bioinformatics techniques were employed to predict the direct interactions of selected circRNAs, microRNAs (miR), and mRNAs. CircRNA_104670 was selected as the target circRNA due to its large multiplier expression in IDD tissues. After luciferase reporter and EGFP/RFP reporter assays, we confirmed that circRNA_104670 directly bound to miR-17-3p, while MMP-2 was the direct target of miR-17-3p. The receiver-operating characteristic (ROC) curve showed that circRNA_104670 and miR-17-3p had good diagnostic significance for IDD (AUC circRNA_104670 = 0.96; AUC miRNA-17-3p = 0.91). A significant correlation was detected between the Pfirrmann grade and expression of circRNA_104670 (r = 0.63; p = 0.00) and miR-17-3p (r = −0.62; p = 0.00). Flow-cytometric analysis and the MTT assay showed that interfering with circRNA_104670 using small interfering RNA (siRNA) inhibited NP cell apoptosis (p < 0.01), and this inhibition was reduced by interfering with miR-17-3p. Interfering with circRNA_104670 suppressed MMP-2 expression and increased extracellular matrix (ECM) formation, which were also reduced by interfering with miR-17-3p. Finally, an MRI evaluation showed that circRNA_104670 inhibition mice had a lower IDD grade compared with control mice (p < 0.01), whereas circRNA_104670 and miRNA-17-3p inhibition mice had a higher IDD grade compared with circRNA_104670 inhibition mice (p < 0.05). CircRNA_104670 is highly expressed in the NP tissues of IDD and acts as a ceRNA during NP degradation.

Synthesis of a Novel N-halamine-based Cyclic Polysiloxane and Its Antibacterial Application on Cotton Fabrics

Jian Liu,Chaohong Dong,Zheng Zhang,Dongdong Wei,Zhou Lu 한국섬유공학회 2020 Fibers and polymers Vol.21 No.2

A novel N-halamine-based cyclic polysiloxane compound (KCNCTSi) was synthesized and used as an antibacterial agent on cotton fabric. The structures were characterized by Fourier transform infrared spectra (FTIR). The surface morphology of treated cotton fabrics was tested by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS). The treated cotton fabrics were tested by thermogravimetric analysis (TGA) and showed good thermal stability. The treated cotton fabrics after chlorination exhibited strong antibacterial efficiency against Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli. The E. coli antibacterial rate was about 98.35 % and the S. aureus antibacterial rate was about 99.51 %. The inhibition zones were 1 mm and 1.5 mm against E. coli and S. aureus when KCNCTSi concentration was 350 g/l. The mechanical properties and whiteness were also investigated. As a result of the performed modifications, cotton fabrics with high antibacterial property were obtained.

RTN4 3'-UTR Insertion/Deletion Polymorphism and Susceptibility to Non-Small Cell Lung Cancer in Chinese Han Population

Lu, De-Yi,Mao, Xu-Hua,Zhou, Ying-Hui,Yan, Xiao-Long,Wang, Wei-Ping,Zheng, Ya-Biao,Xiao, Juan-Juan,Zhang, Ping,Wang, Jian-Guo,Ashwani, Neetika,Ding, Wei-Liang,Jiang, Hua,Shang, Yan,Wang, Ming-Hua Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Nogo protein, encoded by gene reticulon-4 (RTN4), includes three major isoforms by different splicing, named Nogo-A Nogo-B and Nogo-C. Nogo proteins play an important role in the apoptosis of cells, especially in tumor cells. RTN4 single nucleotide polymorphisms (SNPs) can influence the efficiency of transcription and translation thus being related with an individual's predisposition to cancer. The CAA insertion/deletion polymorphism (rs34917480) within RTN4 3'-UTR has been reported to be associated with many cancer types. In order to investigate the relationship between this polymorphism and susceptibility to non-small cell lung cancer (NSCLC) in the Chinese population, we conducted the present case-control study including 411 NSCLC patients and 471 unrelated healthy controls. The genotype distributions were significantly different between cases and controls (p=0.014). We found that the del allele could significantly increase NSCLC risk (ins/ins vs ins/del: p=0.007, OR 1.46, 95%CI=1.11-1.93; dominant model: p=0.004, OR 1.47, 95%CI=1.13-1.92 and allele model: p=0.008, OR 1.35, 95%CI=1.08-1.67). This association was stronger in participants over 60 years old, males and smokers. We therefore conclude that the CAA insertion/deletion polymorphism (rs34917480) contributes to non-small cell lung cancer risk in Chinese population. Age, sex and environmental exposure are also related to carcinogenic effects of rs34917480.

Weight Loss Correlates with Macrophage Inhibitory Cytokine-1 Expression and Might Influence Outcome in Patients with Advanced Esophageal Squamous Cell Carcinoma

Lu, Zhi-Hao,Yang, Li,Yu, Jing-Wei,Lu, Ming,Li, Jian,Zhou, Jun,Wang, Xi-Cheng,Gong, Ji-Fang,Gao, Jing,Zhang, Xiao-Tian,Li, Jie,Li, Yan,Shen, Lin Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

Background: Weight loss during chemotherapy has not been exclusively investigated. Macrophage inhibitory cytokine-1 (MIC-1) might play a role in its etiology. Here, we investigated the prognostic value of weight loss before chemotherapy and its relationship with MIC-1 concentration and its occurrence during chemotherapy in patients with advanced esophageal squamous cell carcinoma (ESCC). Materials and Methods: We analyzed 157 inoperable locally advanced or metastatic ESCC patients receiving first-line chemotherapy. Serum MIC-1 concentrations were assessed before chemotherapy. Patients were assigned into two groups according to their weight loss before or during chemotherapy:>5% weight loss group and ${\leq}5%$ weight loss group. Results: Patients with weight loss>5% before chemotherapy had shorter progression-free survival period (5.8 months vs. 8.7 months; p=0.027) and overall survival (10.8 months vs. 20.0 months; p=0.010). Patients with weight loss >5% during chemotherapy tended to have shorter progression-free survival (6.0 months vs. 8.1 months; p=0.062) and overall survival (8.6 months vs. 18.0 months; p=0.022), and if weight loss was reversed during chemotherapy, survival rates improved. Furthermore, serum MIC-1 concentration was closely related to weight loss before chemotherapy (p=0.001) Conclusions: Weight loss both before and during chemotherapy predicted poor outcome in advanced ESCC patients, and MIC-1 might be involved in the development of weight loss in such patients.

Molecular characterization and comparative analysis of two waxy alleles in barley

Jian Ma,Qian-Tao Jiang,Laroche Andre,Zhen-Xiang Lu,Guo-Yue Chen,Ya-Xi Liu,You-Liang Zheng,Yu-Ming Wei 한국유전학회 2010 Genes & Genomics Vol.32 No.6

Two alleles of the barley waxy locus were characterized from non-waxy cultivar Bowman and waxy cultivar CDC Candle,respectively. Their nucleotide and protein sequences were compared with other known waxy genes. The comparison results indicated that there were 100 polymorphic sites, among which 69 were in the non-coding region and 31 were in the coding region. Out of 100 polymorphic sites, 45 were transversion,35 were transition and 20 were indels. A 397 bp deletion and a 193 bp insertion in the promoter region and a 15bp insertion in the coding region were found in CDC Candle,but not in Bowman. A deletion (11 bp) was detected in Bowman, which exhibited no effects on normal waxy expression. In summary, the 397 bp deletion was supposed to account for the reduction of GBSS I, resulting in the low amylose in CDC Candle; whereas other polymorphic sites might be not correlated with amylose synthesis.

Biomimetic Surface Modification of Polycarbonateurethane Film via Phosphorylcholine-Graft for Resisting Platelet Adhesion

Wei Gao,Jintang Guo,Yakai Feng,Jian Lu,Musammir Khan 한국고분자학회 2012 Macromolecular Research Vol.20 No.10

Phosphorylcholine groups were covalently introduced onto a polycarbonateurethane (PCU) surface in order to create a biomimetic structure on the polymer surfaces. After introducing primary amine groups onto the polymer surface by 1,6-hexanediamine, phosphorylcholine groups were covalently linked onto the surface by the reductive amination between the amino group and the aldehyde group of phosphorylcholine glyceraldehyde (PCGA). The results of water contact angle test, X-ray photoelectron spectroscopy (XPS), and X-ray fluorescence spectrometer (XRF) analysis of the modified films indicated that PCGA had already been covalently linked to the PCU surface. The topographies and surface roughnesses were both imaged and measured by atomic force microscopy (AFM). Scanning electron microscopy (SEM)observation of the PCU films after treatment with platelet-rich plasma demonstrated that platelets had rarely adhered to the surface of the PCGA-grafted PCU films but had mainly adhered to the surface of the blank PCU films. The platelet adhesion result indicated that the PC modified PCU films could resist platelet adhesion after grafting with PCGA, and that these PCGA-grafted PCU materials, potentially, might be applied as blood-contacting materials.

Channel and Gate Workfunction-Engineered CNTFETs for Low-Power and High-Speed Logic and Memory Applications

Wei Wang,Hongsong Xu,Zhicheng Huang,Lu Zhang,Huan Wang,Sitao Jiang,Min Xu,Jian Gao 대한전자공학회 2016 Journal of semiconductor technology and science Vol.16 No.1

Carbon Nanotube Field-Effect Transistors (CNTFETs) have been studied as candidates for post Si CMOS owing to the better electrostatic control and high mobility. To enhance the immunity against short - channel effects (SCEs), the novel channel and gate engineered architectures have been proposed to improve CNTFETs performance. This work presents a comprehensive study of the influence of channel and gate engineering on the CNTFET switching, high frequency and circuit level performance of carbon nanotube field-effect transistors (CNTFETs). At device level, the effects of channel and gate engineering on the switching and high frequency characteristics for CNTFET have been theoretically investigated by using a quantum kinetic model. This model is based on two-dimensional non-equilibrium Green’s functions (NEGF) solved self - consistently with Poisson’s equations. It is revealed that hetero -material - gate and lightly doped drain and source CNTFET (HMG - LDDS - CNTFET) structure can significantly reduce leakage current, enhance control ability of the gate on channel, improve the switching speed, and is more suitable for use in low power, high frequency circuits. At circuit level, using the HSPICE with look - up table(LUT) based Verilog - A models, the impact of the channel and gate engineering on basic digital circuits (inverter, static random access memory cell) have been investigated systematically. The performance parameters of circuits have been calculated and the optimum metal gate workfunction combinations of ФM1/ФM2 have been concluded in terms of power consumption, average delay, stability, energy consumption and power - delay product (PDP). In addition, we discuss and compare the CNTFET-based circuit designs of various logic gates, including ternary and binary logic. Simulation results indicate that LDDS - HMG - CNTFET circuits with ternary logic gate design have significantly better performance in comparison with other structures.