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Estimation of Road Friction Coefficient in Different Road Conditions Based on Vehicle Braking Dynamics

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Chinese Journal of Mechanical Engineering 2017年第4期30卷 982-990页

作者： You-Qun Zhao hai-qing li Fen lin Jian Wang Xue-Wu Ji College of Energy&Power Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Automotive Engineering Shandong Jiaotong UniversityJinan 250023China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China

The accurate estimation of road friction coeffi- cient in the active safety control system has become increasingly prominent. Most previous studies on road friction estimation have only used vehicle longitudinal or lateral dynamics and often ignored the load transfer, which tends to cause inaccurate of the actual road friction coef- ficient. A novel method considering load transfer of front and rear axles is proposed to estimate road friction coef- ficient based on braking dynamic model of two-wheeled vehicle. Sliding mode control technique is used to build the ideal braking torque controller, which control target is to control the actual wheel slip ratio of front and rear wheels tracking the ideal wheel slip ratio. In order to eliminate the chattering problem of the sliding mode controller, integral switching surface is used to design the sliding mode sur- face. A second order linear extended state observer is designed to observe road friction coefficient based on wheel speed and braking torque of front and rear wheels. The proposed road friction coefficient estimation schemes are evaluated by simulation in ADAMS/Car. The results show that the estimated values can well agree with the actual values in different road conditions. The observer can estimate road friction coefficient exactly in real-time andresist external disturbance. The proposed research provides a novel method to estimate road friction coefficient with strong robustness and more accurate.

关键词： Road friction coefficient Real timeestimation External disturbance Different roadconditions

Eosinophilic gastroenteritis associated with eosinophilic cystitis:Computed tomography and magnetic resonance imaging findings

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World Journal of Gastroenterology 2015年第10期21卷 3139-3145页

作者： Shu-Gao Han Ying Chen Zi-Hua Qian li Yang Ri-Sheng Yu Xiu-liang Zhu qing-hai li Qian Chen Department of Radiology Second Affiliated Hospital Zhejiang University School of Medicine Department of Pathology Second Affiliated Hospital Zhejiang University School of Medicine

Eosinophilic gastroenteritis(EG) is a rare,distinct clinical entity,and EG associated with eosinophilic cystitis(EC) is extremely rare and has not been well ***,we report two cases of EG and coexistent EC along with findings from computed tomography(CT) and magnetic resonance imaging(MRI).An 18-year-old male with a history of hematuria,urgency and occasional urodynia for two weeks and a 34-year-old male with a history of abdominal distention for one week were admitted to our *** contrast-enhanced CT in both patients revealed wall thickening in different parts of the gastrointestinal tract with inhomogeneous reinforcement,coexistent with local or diffuse bladder wall thickening with progressive enhancement,and also showed that the bladder mucosal lining was *** MRI showed that the local or diffuse thickened bladder wall was iso-intense on T1-weighted images,hypointense on T2-weighted images,and slightly restricted on diffusion weighted imaging(DWI) in one *** therapy,the thickened wall of the gastrointestinal tract and urinary bladder had improved markedly in the two *** the best of our knowledge,this is the first report on the radiological imaging of EG and coexistent EC by both CT and MRI and the first with DWI findings.

关键词： Eosinophilic gastroenteritis Eosinophilic cystitis

Inhibition of connective tissue growth factor overexpression decreases growth of hepatocellular carcinoma cells in vitro and in vivo

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Chinese Medical Journal 2011年第22期124卷 3794-3799页

作者： JIA Xiao-qin CHENG hai-qing li Hong ZHU Yan li Yu-hua FENG Zhen-qing ZHANG Jian-ping Department of Pathology School of Medicine Yangzhou University Yangzhou Jiangsu 225500 China

Background We have previously found that connective tissue growth factor （CTGF） is highly expressed in a rat model of liver cancer. Here, we examined expression of CTGF in human hepatocellular carcinoma （HCC） cells and its effect on celt growth. Methods Real-time PCR was used to observe expression of CTGF in human HCC cell lines HepG2, SMMC-7721, MHCC-97H and LO2. siRNA for the CTGFgene was designed, synthesized and cloned into a PIk0.1-GFP-SP6 vector to construct a lentivirus-mediated shRNA/CTGF. CTGF mRNA and protein expression in HepG2 cells treated by CTGF-specific shRNA was evaluated by real-time PCR and Western blotting. 3-（4,5-dimethylthiazol-2-yl）- 2,5-diphenyltetrazolium bromide （MTT） assay was utilized to evaluate the growth effect, and a colony formation assay was used for observing clonogenic growth. In vivo, tumor cell proliferation was evaluated in a nude mouse model of xenotransplantation. Statistical significance was determined by t test for comparison between two groups, or analysis of variance （ANOVA） for multiple groups. Results Immunohistochemical staining of CTGF was seen in 35 of 40 HCC samples （87.5%）. CTGF was overexpressed 5-fold in 20 HCC tissues, compared with surrounding non-tumor liver tissue. CTGF mRNA level was 5-8-fold higher in HepG2, SMMC-7721 and MHCC-97H than in LO2 cells. This indicated that the inhibition rate of cell growth was 43% after knockdown of CTGF expression （P 〈0.05）. Soft agar colony formation assay showed that siRNA mediated knockdown of CTGF inhibited colony formation in soft agar of HepG2 cells （P 〈0.05）. The volume of tumors from CTGF-shRNA-expressing cells only accounted for 35% of the tumors from the scrambled control-infected HepG2 cells （P 〈0.05）. Conclusions CTGF was overexpressed in human HCC cells and downregulation of CTGF inhibited HCC growth in vitro and in vivo. Knockdown of CTGFmay be a potential therapeutic strategy for treatment of HCC.

关键词： hepatocellular carcinoma connective tissue growth factor siRNA cell proliferation

A novel approach of proteomics to study the mechanism of action of grape seed proanthocyanidin extracts on diabetic retinopathy in rats

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Chinese Medical Journal 2008年第24期121卷 2544-2552页

作者： li Man MA Ya-bing GAO hai-qing li Bao-ying CHENG Mei XU ling li Xiao-li li Xian-hua Department of Geriatrics Qilu Hospital of Shandong University Jinan Shandong 250012 China

Background Diabetic retinopathy （DR） is a leading cause of visual impairment and blindness among the people of occupational age. To prevent the progress of retina injury, effective therapies directed toward the key molecular target are required. Grape seed proanthocyanidin extracts （GSPE） have been reported to be effective in treating diabetic complications, while little is discussed about the functional protein changes. Methods We used streptozotocin （STZ） to induce diabetes in rats. GSPE （250 mg/kg body weight per day） were administrated to diabetic rats for 24 weeks. Serum glucose, glycated hemoglobin and advanced glycation end products （AGEs） were determined. Consequently, 2-D difference gel electrophoresis and mass spectrometry were used to investigate retina protein profiles among control, STZ-induced diabetic rats, and GSPE treated diabetic rats. Results GSPE significantly reduced the AGEs of diabetic rats （P 〈0.05）. Moreover, GSPE significantly suppressed the vascular lesions of central regions, decreased capillary enlargements and neovascularization, similar to those of the control rats under light microscope. Eighteen proteins were found either up-regulated or down-regulated in the retina of STZ-induced diabetic rats. And seven proteins in the retina of diabetic rats were found to be back-regulated to normal levels after GSPE therapy. These back-regulated proteins are involved in many important biological processes such as heat shock, ubiquitin-proteasome system, cell proliferation, cell growth and glucose metabolism. Conclusions These findings might promote a better understanding for the mechanism of DR, and provide novel targets for evaluating the effects of GSPE therapy.

关键词： grape seed proanthocyanidin extracts diabetic retinopathy advanced glycation end products proteomics

Anti-EGFR therapy in metastatic colorectal cancer:mechanisms and potential regimens of drug resistance

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Gastroenterology Report 2020年第3期8卷 179-191,I0001页

作者： qing-hai li Ying-Zhao Wang Jian Tu Chu-Wei liu Yu-Jie Yuan Run lin Wei-ling He Shi-Rong Cai Yu-Long He Jin-Ning Ye Department of Gastrointestinal Surgery the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Department of Musculoskeletal Oncology the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Department of Radiology the First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China

Cetuximab and panitumumab,as the highly effective antibodies targeting epidermal growth factor receptor(EGFR),have clinical activity in the patients with metastatic colorectal cancer(mCRC).These agents have good curative efficacy,but drug resistance also exists at the same *** effects of KRAS,NRAS,and BRAF mutations and HER2 amplification on the treatment of refractory mCRC have been elucidated and the corresponding countermeasures have been put ***,the changes in EGFR and its ligands,the mutations or amplifications of PIK3CA,PTEN,TP53,MET,HER3,IRS2,FGFR1,and MAP2K1,the overexpression of insulin growth factor-1,the low expression of Bcl-2-interacting mediator of cell death,mismatch repair-deficient,and epigenetic instability may also lead to drug resistance in *** the emergence of drug resistance has genetic or epigenetic heterogeneity,most of these molecular changes relating to it are focused on the key signaling pathways,such as the RAS/RAF/mitogen-activated protein kinase or phosphatidylinositol 3-kinase/Akt/mammalian target of the rapamycin ***,numerous efforts to target these signaling pathways and develop the novel therapeutic regimens have been carried ***,we have reviewed the underlying mechanisms of the resistance to anti-EGFR therapy and the possible implications in clinical practice.

关键词： metastatic colorectal cancer EGFR drug resistance cetuximab panitumumab

Evaluation on the treatment of VX2 transplantable tongue carcinoma in rabbit by intra-arterial perfusion of transgenic CTL

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中国口腔颌面外科杂志 2008年第B5期6卷 114-115页

作者： Tian Jun liao Gui-qing liu hai-chao li qing li Chuan- zhen Du Ri-ehang Wang Jin-xu li Guo-yong Department of Oral and MaxiUofacial Surgery Guanghua Schoolof Stomatology Sun Yat-sen University Guangzhou 510055China

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing Shi Guofan Zhang Yuxuan Zhu Binbin li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

绝热剪切效应对背水靶板的抗侵彻特性影响的研究（英文）

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船舶力学 2017年第3期21卷 352-360页

作者：朱海清李营张谢东张行武汉理工大学交通学院武汉430063

绝热剪切效应是材料破坏的重要机理之一。文章开展了动态冲击作用下的材料绝热剪切试验,计算了绝热条件下材料的塑性温度升高。建立了背水靶板的FEM全流固耦合模型,采用考虑了温度效应的Johnson-cook模型开展了爆炸破片侵彻舰船液舱舱... 详细信息

绝热剪切效应是材料破坏的重要机理之一。文章开展了动态冲击作用下的材料绝热剪切试验,计算了绝热条件下材料的塑性温度升高。建立了背水靶板的FEM全流固耦合模型,采用考虑了温度效应的Johnson-cook模型开展了爆炸破片侵彻舰船液舱舱壁过程的计算。结果表明:(1)材料在高应变率下的绝热温升不可忽略;(2)弹体侵彻背水靶板过程可分为4个典型阶段,分别为墩粗凿坑阶段、碰撞形成速度共同体阶段、绝热剪切阶段和扰动液体阶段;(3)考虑温度效应的剩余速度明显小于不考虑温度效应的剩余速度;速度较低时,是否考虑温度效应预测的剩余速度值差异较小,随着初始速度的增大,差异逐渐增大。

关键词：绝热剪切背水靶板抗侵彻特性

Banach空间上的Hlder度量次正则性的充分条件及参数估值

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云南大学学报（自然科学版） 2018年第6期40卷 1071-1081页

作者：何青海王立将云南大学数学系云南昆明650091

在一般Banach空间中,借助于Ekeland变分原理和多值映射的协导数,证明了Hlder度量次正则性的几个新的充分条件,并对相关重要参数给出估值.最后应用它们研究了不等式系统的Hlder误差界.

关键词： Holder度量次正则法锥 Ekeland变分原理协导数