期刊文献+
共找到35篇文章
< 1 2 >
每页显示 20 50 100
Reinforcement Learning-Based MAS Interception in Antagonistic Environments
1
作者 Siqing Sun Defu Cai +1 位作者 hai-tao zhang Ning Xing 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期270-272,共3页
Dear Editor, As a promising multi-agent systems(MASs) operation, autonomous interception has attracted more and more attentions in these years, where defenders prevent intruders from reaching destinations.So far, most... Dear Editor, As a promising multi-agent systems(MASs) operation, autonomous interception has attracted more and more attentions in these years, where defenders prevent intruders from reaching destinations.So far, most of the relevant methods are applied in ideal environments without agent damages. As a remedy, this letter proposes a more realistic interception method for MASs suffered by damages. 展开更多
关键词 AGENT MAS DESTINATION
下载PDF
Effect of Mn and Mo on microstructure and mechanical properties of Al-Si-Cu-Mg-0.6Fe alloy
2
作者 Hao He Jing Zou +5 位作者 hai-tao zhang Da-chuan Hu Zhi-jun Feng Yu-fei Li Ze-hua Li Hua-cheng Li 《China Foundry》 SCIE EI CAS CSCD 2023年第6期511-518,共8页
Effect of different Mn and Mo contents on microstructure and mechanical properties of Al-Si-Cu-Mg-0.6Fe alloy was studied.Results indicate that the increase of Mo and decrease of Mn lead to a decrease in the size of ... Effect of different Mn and Mo contents on microstructure and mechanical properties of Al-Si-Cu-Mg-0.6Fe alloy was studied.Results indicate that the increase of Mo and decrease of Mn lead to a decrease in the size of theα-Al_(15)(FeMnMo)_(3)Si_(2) phase formed during solidification.Theα-Al_(15)(FeMnMo)_(3)Si_(2) phase reaches a minimum value of about 16.3μm at 0.2wt.%Mo and 0.1wt.%Mn addition.After solution treatment,theα-Al(FeMnMo)Si dispersed phase is precipitated.When only Mn is added,theα-Al(FeMnMo)Si dispersed phase mainly distributes near the grain boundaries,while when only Mo is added,it primarily distributes in the central region of the matrix.When both Mn and Mo are added,the dispersed phase has a larger and denser dispersed region and is uniformly distributed near the Al matrix and grain boundaries.Moreover,the best overall mechanical properties of the alloy are obtained with the combined addition of 0.1wt.%Mn and 0.2wt.%Mo,due to the smaller size ofα-Al_(15)(FeMnMo)_(3)Si_(2) phase and the larger area fraction and higher density of theα-Al(FeMnMo)Si dispersed phase.The yield strength,ultimate tensile strength,and elongation are respectively improved 67.7 MPa,48.5 MPa and 5.3%,respectively,compared to that of the alloy with only 0.3wt.%Mn. 展开更多
关键词 Al-Si-Cu-Mg-0.6Fe alloy Mn and Mo microstructure mechanical properties solution treatment
下载PDF
包覆率对直接水冷铸造法制备包覆铸锭界面组织和性能的影响(英文) 被引量:4
3
作者 张海涛 韩星 +3 位作者 王东涛 邵博 秦克 崔建忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第5期998-1006,共9页
采用数值模拟和实验相结合的方法研究了不同包覆率的AA4045/AA3003铝合金包覆铸锭的制备,并对界面处的温度场和组织性能进行了详细分析。结果表明,采用直接水冷铸造法可得到不同包覆率的铸锭,Si和Mn在界面处发生了互扩散并形成扩散层。... 采用数值模拟和实验相结合的方法研究了不同包覆率的AA4045/AA3003铝合金包覆铸锭的制备,并对界面处的温度场和组织性能进行了详细分析。结果表明,采用直接水冷铸造法可得到不同包覆率的铸锭,Si和Mn在界面处发生了互扩散并形成扩散层。随着包覆率的增加,两种合金接触时界面区域由半固态-固态转变为液态-固态,界面处硬度由HV 47增加到HV 55,扩散层厚度由10增加到25μm。界面处硬度高于AA3003合金一侧,低于4045合金一侧,这是由元素扩散引起固溶强化造成。均匀化退火后,在包覆铸锭被反向挤压成复合管材的过程中,界面处保持层状结构不变,包覆率在变形过程中的遗传性得到证实。 展开更多
关键词 包覆铸锭 包覆率 温度场 界面组织 扩散层 结合强度
下载PDF
离心叶轮分流叶片位置与扩压器相互影响的模拟研究 被引量:9
4
作者 张海涛 邵文洋 +2 位作者 王巍 王晓放 辛建池 《风机技术》 2017年第5期13-19,共7页
叶轮分流叶片周向位置改变,将对叶轮与扩压器内部流场产生干扰。对带分流叶片离心压缩机叶轮及扩压器流场进行数值模拟,结果表明:当叶轮匹配叶片扩压器,分流叶片向主叶片吸力面偏置较居中时,叶轮进出口压比降低3.66%,平均出口气流角增加... 叶轮分流叶片周向位置改变,将对叶轮与扩压器内部流场产生干扰。对带分流叶片离心压缩机叶轮及扩压器流场进行数值模拟,结果表明:当叶轮匹配叶片扩压器,分流叶片向主叶片吸力面偏置较居中时,叶轮进出口压比降低3.66%,平均出口气流角增加1.54°;分流叶片向主叶片压力面偏置相比于居中,叶轮进出口压比增加1.85%,平均出口气流角增加2.09°,分流叶片吸力面侧低能区减小,气流分离受到抑制,叶轮效率提高。因此分流叶片向主叶片压力面偏置有利于提高叶轮性能。但由于分流叶片偏置后叶轮平均出口气流角较居中时变大,对扩压器叶片形成正冲角,在叶片背弧处产生了分离涡,造成扩压器内流场混乱,使扩压器效率降低。因此,分流叶片偏置后与之相匹配的扩压器叶片的安装角也要相应改变,以抑制扩压器内的分离涡及二次流,提高整级效率。 展开更多
关键词 离心叶轮 分流叶片 周向位置 扩压器
下载PDF
Galangin induces apoptosis of hepatocellular carcinoma cells via the mitochondrial pathway 被引量:32
5
作者 hai-tao zhang Liu-Bo Lan +6 位作者 Da-Hua Fan Kai-Dan Zhu Xiao-Yi Chen Min Wen Hui-Ming Liu Guangdong Province China Hui Luo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第27期3377-3384,共8页
AIM:To investigate the mechanism by which galangin,a polyphenolic compound derived from medicinal herbs,induces apoptosis of hepatocellular carcinoma(HCC) cells.METHODS:The 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyl-t... AIM:To investigate the mechanism by which galangin,a polyphenolic compound derived from medicinal herbs,induces apoptosis of hepatocellular carcinoma(HCC) cells.METHODS:The 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay was used to measure cell viability.Apoptosis was evaluated by in situ uptake of propidium iodide and Hoechst 33258 and was then detected by fluorescence microscopy.Protein expressions were detected by Western blotting.To confirm the apoptotic pathway mediated by galangin,cells were transfected by bcl-2 gene to overexpress Bcl-2 or siRNA to down-regulate Bcl-2 expression.RESULTS:Galangin(46.25-370.0 μmol/L) exerted an anti-proliferative effect,induced apoptosis,and decreased mitochondrial membrane potential in a dose and time-dependent manner.Treatment with galangin induced apoptosis by translocating the pro-apoptotic protein Bax to the mitochondria,which released apoptosis-inducing factor and cytochrome c into the cytosol.Overexpression of Bcl-2 attenuated galangin-induced HepG2 cell apoptosis,while decreasing Bcl-2 expression enhanced galangin-induced cell apoptosis.CONCLUSION:Our data suggests that galangin mediates apoptosis through a mitochondrial pathway,and may be a potential chemotherapeutic drug for the treatment of HCC. 展开更多
关键词 Hepatocellular carcinoma GALANGIN MITOCHONDRIA BCL-2 APOPTOSIS
下载PDF
Prostate cancer: an emerging threat to the health of aging men in Asia 被引量:14
6
作者 Ling zhang Bao-Xue Yang +3 位作者 hai-tao zhang Jin-Guo Wang Hong-Liang Wang Xue-Jian Zhao 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第4期574-578,共5页
这研究的目的是由文学评论在在亚洲男人和北美的男人之间的前列腺癌症发生为差别决定并且检验可能的原因。关于癌症发生和死亡的数据为关于癌症(IARC ) 的研究从国际机构的数据库被获得。文学评论被学习在考察同伴的杂志例如出版的相关... 这研究的目的是由文学评论在在亚洲男人和北美的男人之间的前列腺癌症发生为差别决定并且检验可能的原因。关于癌症发生和死亡的数据为关于癌症(IARC ) 的研究从国际机构的数据库被获得。文学评论被学习在考察同伴的杂志例如出版的相关文章进行药,临床的肿瘤学的杂志,为临床医生的一本癌症杂志和 Andrology 的亚洲杂志的新英格兰杂志。为了评估早诊断和幸存,评价, mortality-to-incidence 率比率(先生 / 红外) 从 IARC 数据被计算。由比较在亚洲人和北美的人之间的前列腺癌症数据,我们发现在发生的差别评价,先生 / 红外能主要被归因于在很亚洲的国家与浆液屏蔽前列腺特定的抗原(PSA ) 的年度前列腺癌症的缺乏。屏蔽的 PSA 也处于前列腺癌症死亡率显著地作出贡献到差别,是可能的。前列腺癌症让最高的发生在亚洲美国人在五普通恶意之中评价。然而,前列腺癌症的先生 / 红外比率在癌症之中是最低的。这些数据似乎进一步支持屏蔽的 PSA 的实用性,尽管低风险癌症的百分比比在另外的癌症在前列腺癌症是更大的。前列腺癌症的低发生率不在亚洲反映这疾病的实际统计。从在许多亚洲国家的有限机构的数据似乎偏导真发生和死亡率。改进这种状况,为前列腺癌症屏蔽,以及构造一个全国性的癌症登记系统的合并 PSA,将有用。 展开更多
关键词 前列腺癌 亚洲国家 男性 老年 威胁 健康 研究机构 临床医生
下载PDF
Ethanol induced mitochondria injury and permeability transition pore opening: Role of mitochondria in alcoholic liver disease 被引量:27
7
作者 Ming Yan Ping Zhu +2 位作者 Hui-Min Liu hai-tao zhang Li Liu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第16期2352-2356,共5页
AIM: To observe changes of mitochondria and investigate the effect of ethanol on mitochondrial perme- ability transition pore (PTP), mitochondrial membrane potential (MMP, ΔΨm) and intracellular calcium concentratio... AIM: To observe changes of mitochondria and investigate the effect of ethanol on mitochondrial perme- ability transition pore (PTP), mitochondrial membrane potential (MMP, ΔΨm) and intracellular calcium concentration in hepatocytes by establishing an animal model of alcoholic liver disease (ALD). METHODS: Fourty adult male Wistar rats were randomly divided into two groups, the model group (20) was administered alcohol intragastrically plus an Oliver oil diet to establish an ALD model, and the control group (20) was given an equal amount of normal saline. The ultramicrostructural changes of mitochondria were observed under electron microscopy. Mitochondria of liver was extracted, and patency of PTP, mitochondrial membrane potential (ΔΨm), mitochondrial mass and intracellular calcium concentration of isolated hepacytes were detected by flow cytometry using rhodamine123 (Rh123), Nonyl-Acridine Orange and calcium fluorescent probe Fluo-3/AM, respectively. RESULTS: Membrane and cristae were broken or disappeared in mitochondria in different shapes under electron microscopy. Some mitochondria showed U shape or megamitochondrion. In the model group, liver mitochondria PTP was broken, and mitochondria swelled, the absorbance at 450 nm, A540 decreased (0.0136 ± 0.0025 vs 0.0321 ± 0.0013, model vs control, P < 0.01); mitochondria transmembrane potential (239.4638 ± 12.7263 vs 377.5850 ± 16.8119, P < 0.01) was lowered; mitochondrial mass (17.4350 ± 1.9880 vs 31.6738 ± 3.4930, P < 0.01); and [Ca2+]i was increased in liver cells (7.0020 ± 0.5008 vs 10.2050 ± 0.4701, P < 0.01).CONCLUSION: Chronic alcohol intake might lead to broken mitochondria PTP, decreased mitochondria membrane potential and injury, and elevated intracellular Ca2+ production. Ethanol-induced chondriosome injury may be an important mechanism of alcoholic diseases. 展开更多
关键词 酒精诱发线粒体损伤 酒精性肝病 线粒体渗透转换孔 跨膜电位
下载PDF
Elevated IL-37 levels in the plasma of patients with severe coronary arterycalcification 被引量:11
8
作者 Meng CHAI hai-tao zhang +9 位作者 Yu-Jie ZHOU Qing-Wei JI Qing YANG Yu-Yang LIU Ying-Xin ZHAO Dong-Mei SHI Wei LIU Li-Xia YANG Lin-Lin ZHANC Jing LIANG 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2017年第5期285-291,共7页
Background Coronary artery calcification (CAC) is a predictor of cardiovascular events and plaque burden and is closely associatedwith chronic inflammation. Intedeukin (IL)-37 is a newly discovered member of the I... Background Coronary artery calcification (CAC) is a predictor of cardiovascular events and plaque burden and is closely associatedwith chronic inflammation. Intedeukin (IL)-37 is a newly discovered member of the IL-1 family and is considered an anti-inflammatorycytokine. Our recent study on mice indicated that IL-37 could attenuate atherosclerosis and vascular calcification, which suggests that IL-37could be associated with the development of atherosclerosis and related diseases. The aim of this study was to investigate if IL-37 plays arole in the progression of CAC in patients. Methods Two hundred participants with suspected cardiovascular disease were recruited. Thelevels of plasma IL-37, osteoprotegerin (OPG), hypersensitive C-reactive protein (hsCRP) together with other biochemical parameters weremeasured, and a coronary calcium assessment was carried out by multi-detector row CT. A score of 〈 10 AU (Agatston units) denotes anabsence of CAC, a score of 11-100 AU denotes mild CAC, 101-400 denotes moderate CAC, and 〉 400 AU denotes severe CAC. ResultsOur initial data showed that there were no apparent differences in plasma IL-37 levels among patients with or without mild or moderate CAC.However, IL-37 levels were significantly increased in patients with severe CAC (P 〈 0.001). Similar results were observed for plasma OPGand hsCRP levels. When IL-37 levels in patients with severe calcification were compared with that in all of the other non-severe CAC groups,it became apparent that there was a significant positive correlation between IL-37 level and severe CAC (r = 0.360, P 〈 0.001; OR = 1.033)using Spearrnan's correlation and binary logistic regression analysis. Conclusions This study demonstrates that the anti-inflammatory cy-tokine IL-37 is associated with high coronary calcium levels, suggesting that IL-37 expression may be caused by the activation ofinf/amma-tion and that IL-37 might become a predictor of severe CAC in the future, which requires further investigation. 展开更多
关键词 CORONARY artery CALCIFICATION HIGH-SENSITIVITY C-reactive protein Interleukin-37 OSTEOPROTEGERIN
下载PDF
Intravitreal bevacizumab and Ahmed glaucoma valve implantation in patients with neovascular glaucoma 被引量:12
9
作者 hai-tao zhang Yu-Xin Yang +3 位作者 Ying-Ying Xu Rui-Min Yang Bao-Jun Wang Jun-Xi Hu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第5期837-842,共6页
AIM:To explore the efficacy of preoperative intravitreal bevacizumab(IVB) injection combined with Ahmed glaucoma valve(AGV) implantation in the treatment of neovascular glaucoma(NVG).METHODS:This retrospective study i... AIM:To explore the efficacy of preoperative intravitreal bevacizumab(IVB) injection combined with Ahmed glaucoma valve(AGV) implantation in the treatment of neovascular glaucoma(NVG).METHODS:This retrospective study included 35 eyes from 35 patients who underwent preoperative IVB and AGV implantation for treatment of NVG. Findings such as intraocular pressure(IOP) number of anti-glaucoma medications, visual acuity(VA), surgical success rates,and complications were recorded.RESULTS:AfterAGVimplantation,IOPwas18.2±4.0mmHg,15.5±3.3 mm Hg and 9.8±2.6 mm Hg at 6, 12 and 36 mo,significantly decreased compared with pre-IOP(P <0.01).The number of anti-glaucoma medications was 0.9 ±0.5,0.8 ±0.9 and 0.8 ±0.6 at 6, 12 and 36 mo, significantly decreased compared to pre-treatment(P <0.01). At last visit, there were 19 eyes with stable VA, 4 with VA improvement, 12 with diminished VA and 3 with complete loss light perception. There were 7 cases that failed during 3-year fellow up period. Cumulative probabilities of valve survival by Kaplan-Meier analysis were 82.9%,74.1% and 71.0% at 12, 24 and 36 mo, respectively. Cox stepwise regression analysis found that the survival time was significant associated with the pre-visual acuity <2/400(P <0.05). Post-operative complications occurred in 8eyes, of which hyphema presented in 2 eyes, choroidal effusion in 2 eyes.CONCLUSION:The procedure of preoperative IVB andAGV implantation should be one of treatments for NVG because of its safety and effectiveness. 展开更多
关键词 AHMED GLAUCOMA valve BEVACIZUMAB INTRAVITREAL injection NEOVASCULAR GLAUCOMA
原文传递
Prostate-specific antigen screening for prostate cancer: benefits for patients with highly aggressive prostate cancer 被引量:2
10
作者 Hui-Jie Jia Yang Li +4 位作者 Jin-Guo Wang Ling zhang hai-tao zhang Xue-Jian Zhao Masaaki Kuwahara 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第2期218-220,I0006,共4页
关键词 前列腺癌 特异性抗原 筛查 患者 PSA 服务工作 研究机构 PCa
下载PDF
不同民族白内障患者眼球生物测量及人工晶状体计算的比较 被引量:3
11
作者 曾国燕 吕含韬 +4 位作者 张海涛 范桂琼 张海霞 崔金鹏 张弘 《国际眼科杂志》 CAS 北大核心 2020年第7期1241-1244,共4页
目的:比较红河哈尼族彝族自治州汉族、哈尼族、彝族眼球生物测量的差异,以及SRK-T,Haigis两种公式在不同眼轴中对人工晶状体(IOL)度数预测的准确性,进一步为少数民族地区广大基层医院及防盲治盲项目提供客观的临床依据。方法:选取就诊... 目的:比较红河哈尼族彝族自治州汉族、哈尼族、彝族眼球生物测量的差异,以及SRK-T,Haigis两种公式在不同眼轴中对人工晶状体(IOL)度数预测的准确性,进一步为少数民族地区广大基层医院及防盲治盲项目提供客观的临床依据。方法:选取就诊于我科的白内障患者186例200眼,按不同民族分为3组,以A超分别联合角膜曲率计及角膜地形图进行眼生物测量(眼轴长度、前房深度、角膜曲率)并比较差异;按不同眼轴分为3组后又随机各分为两组,分别以SRK-T,Haigis进行IOL度数预测,搜集术后验光结果,计算绝对预测误差,并进行统计分析。结果:各民族组间的平均眼轴长度、平均前房深度及平均角膜曲率(分别以角膜地形图及角膜曲率计测量)对比均无差异(P>0.05),两种方法测量的平均角膜曲率比较均无差异(P>0.05);三个眼轴组两种方法测量的平均角膜曲率比较无差异(P>0.05),同一眼轴组内比较均无差异(P>0.05);三个眼轴组两种IOL测量公式计算的绝对误差均无差异(P>0.05);短、中眼轴组SRK-T公式计算绝对误差较小,长眼轴组Haigis公式计算绝对误差较小。结论:我科汉族、哈尼族、彝族白内障患者眼球生物测量无差异,角膜地形图及角膜曲率计测量角膜曲率无差异;SRK-T公式及Haigis公式对IOL度数均具有较高预测性,SRK-T公式对中短眼轴患者预测误差较小,Haigis对长眼轴患者预测性更佳。 展开更多
关键词 少数民族地区 基层医院 眼球生物测量 人工晶状体计算公式
下载PDF
Urinary and sexual function changes in benign prostatic hyperplasia patients before and after transurethral columnar balloon dilatation of the prostate 被引量:2
12
作者 Dong-Peng zhang Zheng-Bo Pan hai-tao zhang 《World Journal of Clinical Cases》 SCIE 2022年第20期6794-6802,共9页
BACKGROUND Transurethral columnar balloon dilatation of the prostate(TUCBDP) is a new surgical treatment, but its efficacy remains controversial because of limited clinical application.AIM To investigate the clinical ... BACKGROUND Transurethral columnar balloon dilatation of the prostate(TUCBDP) is a new surgical treatment, but its efficacy remains controversial because of limited clinical application.AIM To investigate the clinical effect of TUCBDP for benign prostatic hyperplasia(BPH).METHODS Overall, 140 patients with BPH who underwent surgical treatment were included in the study. A random number table was used to divide the participants into study and control groups(n = 70 per group). The study group underwent TUCBDP. The prostate resection surgical time, intraoperative blood loss, bladder irrigation time, catheter indwelling time, length of hospital stay, International Prostate Symptom Score(IPSS), maximum urine flow rate(Qmax), residual urine volume(RUV), changes in the International Erectile Function Score(ⅡEF-5) score, serum prostate-specific antigen(PSA), quality of life(QOL) score, and surgical complications were compared in both groups.RESULTS The operation time, intraoperative blood loss volume, bladder flushing time, urinary catheter indwelling time, and length of hospital stay were significantly lower in the study group than in the control group(P < 0.05). There were no significant differences in the IPSS, Qmax, and RUV measurements between the study and control groups(P > 0.05). However, at 3 mo post-surgery, the IPSS and RUV measurements were both lower(P < 0.05) and Qmax values were higher(P < 0.05) compared to the pre-surgery results in both groups. The ⅡEF-5 scores before and 3 mo after surgery were not significantly different between the study and control groups(P > 0.05). At 1 mo after surgery, the ⅡEF-5 score was higher in the study group than in the control group(P < 0.05). The serum PSA levels and QOL scores before treatment and at 1 and 3 mo after treatment were not significantly different between the study and control groups(P > 0.05). However, lower serum PSA levels and QOL scores were observed after 1 and 3 mo of treatment compared to pre-treatment levels in the study group(P < 0.05). The surgical complication rate of the study group(4.29%) was lower than that of the control group(12.86%;P < 0.05).CONCLUSION TUCBDP for BPH and transurethral resection of the prostate can achieve better results, but the former method is associated with less surgical trauma. 展开更多
关键词 Benign prostatic hyperplasia Quality of life Lower urinary tract symptoms Sexual dysfunction Transurethral columnar balloon dilatation of the prostate Transurethral resection of the prostate
下载PDF
The evolution of microstructure and mechanical properties during high-speed direct-chill casting in different Al–Mg_2Si in situ composites 被引量:1
13
作者 Dong-tao Wang hai-tao zhang +3 位作者 Lei Li Hai-lin Wu Ke Qin Jian-zhong Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第9期1080-1089,共10页
The effect of high-speed direct-chill(DC) casting on the microstructure and mechanical properties of Al–Mg_2Si in situ composites and AA6061 alloy was investigated. The microstructural evolution of the Al–Mg_2Si com... The effect of high-speed direct-chill(DC) casting on the microstructure and mechanical properties of Al–Mg_2Si in situ composites and AA6061 alloy was investigated. The microstructural evolution of the Al–Mg_2Si composites and AA6061 alloy was examined by optical microscopy, field-emission scanning electron microscopy(FE-SEM) and transmission electron microscopy(TEM). The results revealed that an increase of the casting speed substantially refined the primary Mg_2Si particles(from 28 to 12 μm), the spacing of eutectic Mg_2Si(from 3 to 0.5 μm), and the grains of AA6061 alloy(from 102 to 22 μm). The morphology of the eutectic Mg_2Si transformed from lamellar to rod-like and fibrous with increasing casting speed. The tensile tests showed that the yield strength, tensile strength, and elongation improved at higher casting speeds because of refinement of the Mg_2Si phase and the grains in the Al–Mg_2Si composites and the AA6061 alloy. High-speed DC casting is demonstrated to be an effective method to improve the mechanical properties of Al–Mg_2Si composites and AA6061 alloy billets. 展开更多
关键词 Al–Mg2Si in SITU composite CASTING speed GRAIN size primary MG2SI mechanical property
下载PDF
Interfacial characteristics and properties of a low-clad-ratio AA4045/AA3003 cladding billet fabricated by semi-continuous casting 被引量:1
14
作者 Xing Han hai-tao zhang +3 位作者 Bo Shao Lei Li Ke Qin Jian-zhong Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第9期1097-1103,共7页
A low-clad-ratio AA4045/AA3003 cladding billet was fabricated using a semi-continuous casting process and was subsequently extruded indirectly into a cladding pipe. The temperature distribution near the interface was ... A low-clad-ratio AA4045/AA3003 cladding billet was fabricated using a semi-continuous casting process and was subsequently extruded indirectly into a cladding pipe. The temperature distribution near the interface was measured. The microstructures, elemental distribution, Vickers hardness around the bonding interface, and the interfacial shear strength were examined. The results showed that the interface temperature rebounded when AA4045 melt contacted the supporting layer. The two alloys bonded well, with few defects, via the diffusion of Si and Mn in the temperature range from 569℃ to 632℃. The mean shear strength of the bonding interface was 82.3 MPa, which was greater than that of AA3003(75.8 MPa), indicating that the two alloys bonded with each other metallurgically via elemental interdiffusion. Moreover, no relative slip occurred between the two alloys during the extrusion process. 展开更多
关键词 aluminum alloys metal cladding CASTING INTERDIFFUSION interfaces
下载PDF
Step-coordination Algorithm of Traffic Control Based on Multi-agent System 被引量:1
15
作者 hai-tao zhang Fang Yu Wen Li 《International Journal of Automation and computing》 EI 2009年第3期308-313,共6页
Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes tra... Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system (MAS) is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study. 展开更多
关键词 交通控制方法 多代理系统 控制算法 协调 多Agent系统 制剂技术 代理技术 交通管制
下载PDF
Data-Driven Discovery of Stochastic Differential Equations 被引量:1
16
作者 Yasen Wang Huazhen Fang +12 位作者 Junyang Jin Guijun Ma Xin He Xing Dai Zuogong Yue Cheng Cheng hai-tao zhang Donglin Pu Dongrui Wu Ye Yuan Jorge Gonçalves Jürgen Kurths Han Ding 《Engineering》 SCIE EI CAS 2022年第10期244-252,共9页
Stochastic differential equations(SDEs)are mathematical models that are widely used to describe complex processes or phenomena perturbed by random noise from different sources.The identification of SDEs governing a sy... Stochastic differential equations(SDEs)are mathematical models that are widely used to describe complex processes or phenomena perturbed by random noise from different sources.The identification of SDEs governing a system is often a challenge because of the inherent strong stochasticity of data and the complexity of the system’s dynamics.The practical utility of existing parametric approaches for identifying SDEs is usually limited by insufficient data resources.This study presents a novel framework for identifying SDEs by leveraging the sparse Bayesian learning(SBL)technique to search for a parsimonious,yet physically necessary representation from the space of candidate basis functions.More importantly,we use the analytical tractability of SBL to develop an efficient way to formulate the linear regression problem for the discovery of SDEs that requires considerably less time-series data.The effectiveness of the proposed framework is demonstrated using real data on stock and oil prices,bearing variation,and wind speed,as well as simulated data on well-known stochastic dynamical systems,including the generalized Wiener process and Langevin equation.This framework aims to assist specialists in extracting stochastic mathematical models from random phenomena in the natural sciences,economics,and engineering fields for analysis,prediction,and decision making. 展开更多
关键词 Data-driven method System identification Sparse Bayesian learning Stochastic differential equations Random phenomena
下载PDF
Porosity Calculation of Tight Sand Gas Reservoirs with GA-CM Hybrid Optimization Log Interpretation Method 被引量:1
17
作者 Ya-Nan Duan Bao-Zhi Pan +2 位作者 Xue Han hai-tao zhang Xiao-Ming Yang 《Journal of Geoscience and Environment Protection》 2014年第3期92-98,共7页
Tight sand gas reservoirs are our country’s fairly rich unconventional natural gas resources, and their exploration and development is of prime importance. Sulige Gas Field which located in the northern Ordos Basin i... Tight sand gas reservoirs are our country’s fairly rich unconventional natural gas resources, and their exploration and development is of prime importance. Sulige Gas Field which located in the northern Ordos Basin is tight sand gas reservoirs. It is typically featured by low porosity and low permeability, and the error of porosity calculation by traditional methods is larger. Multicomponent explanation model is built by analyzing the thin slice data, and the objective function is got according to the concept of optimization log interpretation method. This paper puts the Genetic Algorithm and the Complex Algorithm together to form the GA-CM Hybrid Algorithm for searching the optimal solution of the objective function, getting the porosity of tight sandstone gas reservoirs. The deviation got by this method is lesser compared with the core porosity, with a high reliability. 展开更多
关键词 POROSITY TIGHT SAND Gas Reservoirs LOW POROSITY and LOW Permeability GA-CM Optimization Multicomponent Explanation Model
下载PDF
Development of inclusions in 3104 alloy melt during heating and holding treatments
18
作者 Xiao-xiong Luo hai-tao zhang +4 位作者 Xing Han Shi-jie Guo Dan-dan Chen Jian-zhong Cui Hiromi Nagaumi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2016年第6期637-644,共8页
Developments in the contents of different typical inclusions in 3104 alloy melt were described during heating and holding processing. The settling process of inclusion particles was investigated by measuring the conte... Developments in the contents of different typical inclusions in 3104 alloy melt were described during heating and holding processing. The settling process of inclusion particles was investigated by measuring the contents of inclusions in the surface, center, and bottom layers of the molten metal. In the results, main inclusions observed and determined by Prefil and PoD FA methods are MgO, Al_2O_3, spinel(MgAl_2O_4), and TiB_2 particles or thin films. It is found that some small particles of Al_2O_3 and MgO are transformed into spinel particles, and the formation rate increases as the temperature and the holding period of melt increase. The content of inclusions increases from 3.37 mm^2×kg^(-1) to 7.54 mm^2×kg^(-1) and then decreases to 3.08 mm^2×kg^(-1) after holding for 90 min. This is attributed to a settling phenomenon and a significant increase in settling velocity after holding for 60 min. The content of inclusion particles decreases by means of settlement and flotation in liquid aluminum with an increase in holding time. The theoretical analysis and experiment results are in essential agreement with those from industrial production. 展开更多
关键词 合金熔体 夹杂物 加热 TIB2颗粒 MGAL2O4 Al2O3 金属表面 沉淀过程
下载PDF
Development and Validation of a Prognostic Risk Score System for COVID-19 Inpatients:A Multi-Center Retrospective Study in China
19
作者 Ye Yuan Chuan Sun +24 位作者 Xiuchuan Tang Cheng Cheng Laurent Mombaerts Maolin Wang Tao Hu Chenyu Sun Yuqi Guo Xiuting Li Hui Xu Tongxin Ren Yang Xiao Yaru Xiao Hongling Zhu Honghan Wu Kezhi Li Chuming Chen Yingxia Liu Zhichao Liang Zhiguo Cao hai-tao zhang Ioannis Ch.Paschaldis Quanying Liu Jorge Goncalves Qiang Zhong Li Yan 《Engineering》 SCIE EI 2022年第1期116-121,共6页
Coronavirus disease 2019(COVID-19)has become a worldwide pandemic.Hospitalized patients of COVID-19 suffer from a high mortality rate,motivating the development of convenient and practical methods that allow clinician... Coronavirus disease 2019(COVID-19)has become a worldwide pandemic.Hospitalized patients of COVID-19 suffer from a high mortality rate,motivating the development of convenient and practical methods that allow clinicians to promptly identify high-risk patients.Here,we have developed a risk score using clinical data from 1479 inpatients admitted to Tongji Hospital,Wuhan,China(development cohort)and externally validated with data from two other centers:141 inpatients from Jinyintan Hospital,Wuhan,China(validation cohort 1)and 432 inpatients from The Third People’s Hospital of Shenzhen,Shenzhen,China(validation cohort 2).The risk score is based on three biomarkers that are readily available in routine blood samples and can easily be translated into a probability of death.The risk score can predict the mortality of individual patients more than 12 d in advance with more than 90%accuracy across all cohorts.Moreover,the Kaplan-Meier score shows that patients can be clearly differentiated upon admission as low,intermediate,or high risk,with an area under the curve(AUC)score of 0.9551.In summary,a simple risk score has been validated to predict death in patients infected with severe acute respiratory syndrome coronavirus 2(SARS-CoV-2);it has also been validated in independent cohorts. 展开更多
关键词 COVID-19 Risk score Mortality risk prediction
下载PDF
Research on Determination of the Main Factors Influencing the Gas Well Post-Frac Productivity Prediction for Tight Sandstone Reservoirs Based on Factors Analysis
20
作者 Bi-Ci Jiang Bao-Zhi Pan +3 位作者 hai-tao zhang Xiao-Ming ang Gang Chen Wen-Bin Liu 《Journal of Geoscience and Environment Protection》 2014年第3期60-65,共6页
With the characteristics such as low porosity, low permeability and low gas saturation, tight sandstone reservoirs almost have no natural capacity and need to be fractured (or fracturing) for productivity. Therefore, ... With the characteristics such as low porosity, low permeability and low gas saturation, tight sandstone reservoirs almost have no natural capacity and need to be fractured (or fracturing) for productivity. Therefore, fracturing capacity prediction is very necessary. However there were so many factors, and the relations between the factor and the post-frac productivity are complex. In this study, first of all factors are concluded from the gas well stable productivity formula, then I used factor analysis to look for the main factors from the logging parameters and fracturing parameters in SULIGE area. This study could provide basal references for the gas post-frac productivity prediction in tight sandstone reservoirs. 展开更多
关键词 FACTOR Analysis TIGHT SANDSTONE SULIGE Region Post-Frac PRODUCTIVITY
下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部