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Effect of low-speed waterjet pressure on the rock-breaking performance of unsubmerged cavitating abrasive waterjet
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作者 Chen-Xing Fan Deng Li +1 位作者 Yong Kang hai-tao zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2638-2649,共12页
Unsubmerged cavitating abrasive waterjet(UCAWJ)has been shown to artificially create a submerged environment that produces shear cavitation,which effectively enhances rock-breaking performance.The shear cavitation gen... Unsubmerged cavitating abrasive waterjet(UCAWJ)has been shown to artificially create a submerged environment that produces shear cavitation,which effectively enhances rock-breaking performance.The shear cavitation generation and collapse intensity depend on the pressure difference between the intermediate high-speed abrasive waterjet and the coaxial low-speed waterjet.However,the effect of the pressure of the coaxial low-speed waterjet is pending.For this purpose,the effect of low-speed waterjet pressure on rock-breaking performance at different standoff distances was experimentally investigated,and the effects of erosion time and ruby nozzle diameter on erosion performance were discussed.Finally,the micromorphology of the sandstone was observed at different locations.The results show that increased erosion time and ruby nozzle diameter can significantly improve the rock-breaking performance.At different standoff distances,the mass loss increases first and then decreases with the increase of low-speed waterjet pressure,the maximum mass loss is 10.4 g at a low-speed waterjet pressure of0.09 MPa.The surface morphology of cavitation erosion was measured using a 3D profiler,the increase in both erosion depth and surface roughness indicated a significant increase in the intensity of the shear cavitation collapse.At a low-speed waterjet pressure of 0.18 MPa,the cavitation erosion surface depth can reach 600μm with a roughness of 127μm. 展开更多
关键词 Rock-breaking Coaxial low-speed waterjet pressure Abrasive waterjet CAVITATION Unsubmerged environment
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The Immense Impact of Reverse Edges on Large Hierarchical Networks
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作者 Haosen Cao Bin-Bin Hu +7 位作者 Xiaoyu Mo Duxin Chen Jianxi Gao Ye Yuan Guanrong Chen Tamás Vicsek Xiaohong Guan hai-tao zhang 《Engineering》 SCIE EI CAS CSCD 2024年第5期240-249,共10页
Hierarchical networks are frequently encountered in animal groups,gene networks,and artificial engineering systems such as multiple robots,unmanned vehicle systems,smart grids,wind farm networks,and so forth.The struc... Hierarchical networks are frequently encountered in animal groups,gene networks,and artificial engineering systems such as multiple robots,unmanned vehicle systems,smart grids,wind farm networks,and so forth.The structure of a large directed hierarchical network is often strongly influenced by reverse edges from lower-to higher-level nodes,such as lagging birds’howl in a flock or the opinions of lowerlevel individuals feeding back to higher-level ones in a social group.This study reveals that,for most large-scale real hierarchical networks,the majority of the reverse edges do not affect the synchronization process of the entire network;the synchronization process is influenced only by a small part of these reverse edges along specific paths.More surprisingly,a single effective reverse edge can slow down the synchronization of a huge hierarchical network by over 60%.The effect of such edges depends not on the network size but only on the average in-degree of the involved subnetwork.The overwhelming majority of active reverse edges turn out to have some kind of“bunching”effect on the information flows of hierarchical networks,which slows down synchronization processes.This finding refines the current understanding of the role of reverse edges in many natural,social,and engineering hierarchical networks,which might be beneficial for precisely tuning the synchronization rhythms of these networks.Our study also proposes an effective way to attack a hierarchical network by adding a malicious reverse edge to it and provides some guidance for protecting a network by screening out the specific small proportion of vulnerable nodes. 展开更多
关键词 SYNCHRONIZABILITY Large hierarchical networks Reverse edges Information flows Complex networks
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使用深度学习在CTA扫描卷下实现主动脉夹层分类和直径测量的双功能系统
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作者 Zhihui Huang Rui Wang +6 位作者 Hui Yu Yifan Xu Cheng Cheng Guangwei Wang Haosen Cao Xiang Wei hai-tao zhang 《Engineering》 SCIE EI CAS CSCD 2024年第3期83-91,共9页
Acute aortic dissection is one of the most life-threatening cardiovascular diseases,with a high mortality rate.Its prevalence ranges from 0.2%to 0.8%in humans,resulting in a significant number of deaths due to being m... Acute aortic dissection is one of the most life-threatening cardiovascular diseases,with a high mortality rate.Its prevalence ranges from 0.2%to 0.8%in humans,resulting in a significant number of deaths due to being missed in manual examinations.More importantly,the aortic diameter—a critical indicator for surgical selection—significantly influences the outcomes of surgeries post-diagnosis.Therefore,it is an urgent yet challenging mission to develop an automatic aortic dissection diagnostic system that can recognize and classify the aortic dissection type and measure the aortic diameter.This paper offers a dual-functional deep learning system called aortic dissections diagnosis-aiding system(DDAsys)that enables both accurate classification of aortic dissection and precise diameter measurement of the aorta.To this end,we created a dataset containing 61190 computed tomography angiography(CTA)images from 279 patients from the Division of Cardiovascular Surgery at Tongji Hospital,Wuhan,China.The dataset provides a slice-level summary of difficult-to-identify features,which helps to improve the accuracy of both recognition and classification.Our system achieves a recognition F1 score of 0.984,an average classification F1 score of 0.935,and the respective measurement precisions for ascending and descending aortic diameters are 0.994 mm and 0.767 mm root mean square error(RMSE).The high consistency(88.6%)between the recommended surgical treatments and the actual corresponding surgeries verifies the capability of our system to aid clinicians in developing a more prompt,precise,and consistent treatment strategy. 展开更多
关键词 Aortic dissections Computed tomography angiography CLASSIFICATION Deep learning
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Reinforcement Learning-Based MAS Interception in Antagonistic Environments
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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
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Effect of Mn and Mo on microstructure and mechanical properties of Al-Si-Cu-Mg-0.6Fe alloy
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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
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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:10
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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
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Ethanol induced mitochondria injury and permeability transition pore opening: Role of mitochondria in alcoholic liver disease 被引量:27
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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 Alcoholic liver disease Chondriosome APOPTOSIS Ultra microstructure Membrane potentials Permeability transition pore Transmembrane potential chondriosome mass Ca^2+
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Galangin induces apoptosis of hepatocellular carcinoma cells via the mitochondrial pathway 被引量:32
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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
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Elevated IL-37 levels in the plasma of patients with severe coronary arterycalcification 被引量:12
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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
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Prostate cancer: an emerging threat to the health of aging men in Asia 被引量:14
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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
The aim of this study was to determine and examine the possible reasons for the difference in prostate cancer incidence between Asian men and North American men by literature review. Data regarding cancer incidence an... The aim of this study was to determine and examine the possible reasons for the difference in prostate cancer incidence between Asian men and North American men by literature review. Data regarding cancer incidence and mortality were obtained from the database of the International Agency for Research on Cancer (IARC). A literature review was conducted by studying related articles published in peer-reviewed journals such as the The New England Journal of Medicine, Journal of Clinical Oncology, A Cancer Journal for Clinicians and Asian Journal of Andrology. To evaluate the early diagnosis and survival rates, the mortality.to-incidence rate ratio (MR/IR) was calculated from the IARC data. By comparing prostate cancer data between Asian men and North American men, we found that differences in the incidence rate and MR/IR could be attributed largely to a lack of annual prostate cancer screening with serum prostate-specific antigen (PSA) in most Asian countries. It is likely that PSA screening also contributes significantly to the differences in prostate cancer mortality rates. Prostate cancer has the highest incidence rate among five common malignancies in Asian Americans. However, the MR/IR ratio of prostate cancer is the lowest among cancers. These data seem to further support the usefulness of PSA screening, even though the percentage of low risk cancers is greater in prostate cancer than in other cancers. The low incidence rate of prostate cancer does not reflect the actual statistics of this disease in Asia. The data from limited institutions in many Asian countries seem to bias the true incidence and mortality rates. To improve this situation, incorporating PSA screening for prostate cancer, as well as constructing a nationwide cancer registration system, will be helpful. 展开更多
关键词 INCIDENCE MORTALITY prostate cancer prostate-specific antigen
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Intravitreal bevacizumab and Ahmed glaucoma valve implantation in patients with neovascular glaucoma 被引量:12
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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
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Computation of synthetic surface heat transfer coefficient of 7B50 ultra-high-strength aluminum alloy during spray quenching 被引量:6
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作者 Lei KANG Gang ZHAO +1 位作者 Ni TIAN hai-tao zhang 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第5期989-997,共9页
According to inverse heat transfer theory, the evolutions of synthetic surface heat transfer coefficient(SSHTC) of the quenching surface of 7B50 alloy during water-spray quenching were simulated by the Pro CAST soft... According to inverse heat transfer theory, the evolutions of synthetic surface heat transfer coefficient(SSHTC) of the quenching surface of 7B50 alloy during water-spray quenching were simulated by the Pro CAST software based on accurate cooling curves measured by the modified Jominy specimen and temperature-dependent thermo-physical properties of 7 B50 alloy calculated using the JMat Pro software. Results show that the average cooling rate at 6 mm from the quenching surface and 420-230 ℃(quench sensitive temperature range) is 45.78℃/s. The peak-value of the SSHTC is 69 kW/(m^2·K) obtained at spray quenching for 0.4 s and the corresponding temperature of the quenching surface is 160 ℃. In the initial stage of spray quenching, the phenomenon called "temperature plateau" appears on the cooling curve of the quenching surface. The temperature range of this plateau is 160-170℃ with the duration about 3 s. During the temperature plateau, heat transfer mechanism of the quenching surface transforms from nucleate boiling regime to single-phase convective regime. 展开更多
关键词 7B50 aluminum alloy water-spray quenching inverse heat transfer theory synthetic surface heat transfer coefficient cooling curve
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Effect of clad ratio on interfacial microstructure and properties of cladding billets via direct-chill casting process 被引量:4
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作者 hai-tao zhang Xing HAN +3 位作者 Dong-tao WANG Bo SHAO Ke QIN Jian-zhong CUI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第5期998-1006,共9页
Numerical simulation and experiments were introduced to develop AA4045/AA3003 cladding billets with different clad-ratios. The temperature fields, microstructures and mechanical properties near interface were investig... Numerical simulation and experiments were introduced to develop AA4045/AA3003 cladding billets with different clad-ratios. The temperature fields, microstructures and mechanical properties near interface were investigated in detail. The results show that cladding billets with different clad-ratios were fabricated successfully. Si and Mn elements diffused across the bonding interface and formed diffusion layer. With the increase of clad-layer thickness, the interfacial region transforms from semisolid-solid state to liquid-solid state and the diffusion layer increased from 10 to 25 μm. The hardness at interface is higher than that of AA3003 side but lower than that of the other side. The bonding strength increased with the clad-layer thickness, attributing to solution strengthening due to elements diffusion. The cladding billets were extruded into clad pipe by indirect extrusion process after homogenization. The clad pipe remained the interfacial characteristics of as-cast cladding billet and the heredity of clad-ratio during deformation was testified. 展开更多
关键词 cladding billet clad ratio temperature field interfacial microstzucture diffusion layer bonding strength
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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
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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
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Urinary and sexual function changes in benign prostatic hyperplasia patients before and after transurethral columnar balloon dilatation of the prostate 被引量:2
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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
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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
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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
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Data-Driven Discovery of Stochastic Differential Equations 被引量:1
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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
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Step-coordination Algorithm of Traffic Control Based on Multi-agent System 被引量:1
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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 Traffic control coordination algorithm multi-agent system (MAS) traffic control system agent.
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Interfacial characteristics and properties of a low-clad-ratio AA4045/AA3003 cladding billet fabricated by semi-continuous casting 被引量:2
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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
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Porosity Calculation of Tight Sand Gas Reservoirs with GA-CM Hybrid Optimization Log Interpretation Method 被引量:1
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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
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