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基于转频脊线的滚动轴承阶次分析故障诊断
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作者 张小丽 范攀锋 +3 位作者 李贤耀 王保建 梁旺 王芳珍 《噪声与振动控制》 北大核心 2025年第1期139-145,共7页
针对变转速状况下部分设备难以安装转速计而导致转速信息缺失的问题,提出基于阶次分析的无转速计滚动轴承故障诊断方法。同时针对振动信号处理中时频脊线提取精度不高、轴承转频脊线识别困难等问题,提出基于快速路径优化算法的多时频脊... 针对变转速状况下部分设备难以安装转速计而导致转速信息缺失的问题,提出基于阶次分析的无转速计滚动轴承故障诊断方法。同时针对振动信号处理中时频脊线提取精度不高、轴承转频脊线识别困难等问题,提出基于快速路径优化算法的多时频脊线提取方法和基于脊线拟合优度指标的转频脊线识别方法。首先,利用快速路径优化算法可以抑制相邻时刻频率跳变的特点,提高时频脊线提取精度;其次,通过计算脊线拟合优度值的方法从所提取的多条时频脊线中识别出转频脊线;最后利用识别的转频脊线结合阶次分析,对滚动轴承故障实验振动信号进行分析,验证所提滚动轴承故障诊断方法的可行性。 展开更多
关键词 故障诊断 滚动轴承 脊线识别 阶次分析 变转速工况
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两阶段智能优化算法求解紧凑型带钢生产热轧调度问题
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作者 梁望 钱斌 +2 位作者 胡蓉 张梓琪 张长胜 《计算机集成制造系统》 北大核心 2025年第1期102-116,共15页
针对实际生产中广泛存在的紧凑型带钢生产热轧调度问题(HRSP_CSP),提出一种两阶段智能优化算法(TIOA)进行求解。为合理控制成本并确保效益,采用主次目标进行优化。主目标为如何加入最少的无委托带钢(即订单外生产的带钢)来构成最小轧制... 针对实际生产中广泛存在的紧凑型带钢生产热轧调度问题(HRSP_CSP),提出一种两阶段智能优化算法(TIOA)进行求解。为合理控制成本并确保效益,采用主次目标进行优化。主目标为如何加入最少的无委托带钢(即订单外生产的带钢)来构成最小轧制批次;次目标为如何在主目标确定的轧制批次中,确定各批次内的带钢集合和轧制顺序,以实现轧制平均平滑率(即各批次带钢轧制平滑率的平均值)最小。基于HRSP_CSP的特点,TIOA设计为两阶段优化算法。在TIOA的前一阶段,分析问题特征,提出启发式算法获取问题的最优解(即最小轧制批次)。在TIOA的后一阶段,分析问题性质,提出改进人工蜂群(IABC)算法在较短时间内获取问题的优质解。IABC算法采用基于集合的编码方式,并设计问题解的最优解码策略来提升解的质量,同时设计结合无效邻域判断策略的两类Swap邻域操作以增强局部搜索效率。通过仿真实验和算法对比,验证了TIOA的有效性。 展开更多
关键词 启发式算法 热轧调度 人工蜂群 紧凑型带钢生产
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Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway
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作者 Jiayi wang Mengke Zhao +5 位作者 Dong Fu Meina wang Chao Han Zhongyue Lv liang wang Jing Liu 《Neural Regeneration Research》 SCIE CAS 2025年第11期3245-3258,共14页
Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem ce... Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived treatments.This lays a foundation for the development of potentially potent new treatment modalities for ischemic stroke.However,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical translation.To promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic stroke.We found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal apoptosis.The human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase B,and these effects were reversed by treatment with a phosphoinositide 3-kinase inhibitor.These findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling pathway.Finally,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety profile.Therefore,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke. 展开更多
关键词 behavior EXOSOME extracellular vesicles ischemic stroke mammalian target of rapamycin(mTOR) middle cerebral artery occlusion neural stem cells neuronal apoptosis phosphoinositide 3-kinase(PI3K) protein kinase B(AKT)
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Targeted maintenance therapy for a young woman with cervical rhabdomyosarcoma:A case report and review of literature
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作者 Huan-Ran Ma Dan Zhang +4 位作者 Li Li Lin Qi liang wang Yi-Tong Li Ya-Ru wang 《World Journal of Clinical Oncology》 2025年第3期151-161,共11页
BACKGROUND Rhabdomyosarcoma of the uterine cervix is a rare form of soft-tissue sarcoma predominantly affecting young women,with no established standard treatment protocol.CASE SUMMARY This report presents a case of a... BACKGROUND Rhabdomyosarcoma of the uterine cervix is a rare form of soft-tissue sarcoma predominantly affecting young women,with no established standard treatment protocol.CASE SUMMARY This report presents a case of a 17-year-old female patient presenting with in-termittent,non-cyclical vaginal bleeding and associated lower abdominal pain.Pelvic magnetic resonance imaging and additional examinations led to the dia-gnosis of cervical rhabdomyosarcoma.The primary treatment options for uterine cervical rhabdomyosarcoma include surgery,with or without adjuvant chemo-therapy and radiotherapy.This patient underwent surgery followed by a posto-perative chemotherapy regimen of gemcitabine combined with docetaxel and bevacizumab.After 19 months of follow-up,the patient showed no signs of re-currence and maintained good overall health.Given the rarity of cervix rhab-domyosarcoma,this case is presented to provide insights into the diagnosis and treatment of this condition.CONCLUSION This suggests that bevacizumab may demonstrate potential efficacy in the treat-ment of cervical rhabdomyosarcoma.In the future,targeted therapy is expected to play an increasingly significant role in the management of rhabdomyosarcoma. 展开更多
关键词 RHABDOMYOSARCOMA Cervical rhabdomyosarcoma Targeted therapy Chemo-therapy PROGNOSIS Case report
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Early and accurate diagnosis and selection of appropriate treatment plans are crucial for patients with gastrointestinal hemangiomas
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作者 Zhou Chen liang wang Peng-Jie Yu 《World Journal of Gastrointestinal Surgery》 2025年第2期303-307,共5页
Gastrointestinal hemangioma(GIH)is clinically rare,accounting for 7%-10%of benign gastrointestinal tumors and 0.5%of systemic hemangiomas.GIH can occur as either solitary or multiple lesions,with gastrointestinal blee... Gastrointestinal hemangioma(GIH)is clinically rare,accounting for 7%-10%of benign gastrointestinal tumors and 0.5%of systemic hemangiomas.GIH can occur as either solitary or multiple lesions,with gastrointestinal bleeding as a significant clinical manifestation.Understanding the clinical and endoscopic features of GIH is essential for improving diagnostic accuracy,particularly through endoscopy and selective arteriography,which are highly effective in diagnosing GIH and preventing misdiagnosis and inappropriate treatment.Upon confirmed diagnosis,it is essential to thoroughly evaluate the patient's condition to determine the most suitable treatment modality—whether surgical,endoscopic,or minimally invasive intervention.The minimally invasive interventional partial embolization therapy using polyvinyl alcohol particles,proposed and implemented by Pospisilova et al,has achieved excellent clinical outcomes.This approach reduces surgical trauma and the inherent risks of traditional surgical treatments. 展开更多
关键词 HEMANGIOMA Gastrointestinal hemangioma Gastrointestinal hemorrhage Minimally invasive interventional treatment Selective embolization
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Early identification and multidisciplinary management of immune checkpoint inhibitors associated colitis can improve patient outcomes
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作者 liang wang Sheng-Mei Zhang Xiao-Qian Chen 《World Journal of Gastrointestinal Surgery》 2025年第1期1-7,共7页
Currently,the use of immune checkpoint inhibitors(ICIs)has shown notable clinical efficacy in treating various malignant tumors,significantly improving patient prognosis.However,while ICIs enhance the body’s anti-tum... Currently,the use of immune checkpoint inhibitors(ICIs)has shown notable clinical efficacy in treating various malignant tumors,significantly improving patient prognosis.However,while ICIs enhance the body’s anti-tumor effects,they can also trigger immune-related adverse events(irAEs),with ICI-associated colitis being one of the more prevalent forms.This condition can disrupt treatment,necessitate drug discontinuation,and adversely affect therapeutic outcomes.In severe cases,irAEs may even become life-threatening.A recent case report by Hong et al highlights the importance of vigilance for ICI-associated colitis in patients experiencing symptoms such as diarrhea and abdominal pain,which can arise both during and even after completion of ICI treatment.Early identification,multidisciplinary management,and continuous monitoring of patients are essential steps to further improve outcomes. 展开更多
关键词 Immune checkpoint inhibitors Immune-related adverse events Immune checkpoint inhibitor-associated colitis IMMUNOTHERAPY Multidisciplinary management
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无机及分析化学一流课程建设的探索与实践 被引量:1
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作者 余凡 李艾华 +4 位作者 刘芸 朱天容 王亮 徐俊晖 王亚珍 《大学化学》 CAS 2024年第8期36-43,共8页
一流课程是人才培养的核心载体,是实现人才培养目标的关键。在“双一流”建设背景下,以江汉大学无机及分析化学省级一流课程为例,探讨了本课程建设的思路和实践。课程从“专业教育和思政教育融合、教学内容与资源整合、线上线下教学方... 一流课程是人才培养的核心载体,是实现人才培养目标的关键。在“双一流”建设背景下,以江汉大学无机及分析化学省级一流课程为例,探讨了本课程建设的思路和实践。课程从“专业教育和思政教育融合、教学内容与资源整合、线上线下教学方式混合”的三个方面开展教学改革,构建了“慕课+翻转课堂+问题导向学习(PBL)”的教学模式及“三段七步”教学法,激发学生学习积极性,培养了学生自主学习能力。相关举措可为地方高校无机及分析化学课程建设提供参考。 展开更多
关键词 一流课程 无机及分析化学 混合式教学
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基于GADF-CWT-GCNN的滚动轴承故障诊断方法研究
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作者 张小丽 罗鑫 +2 位作者 李敏 梁旺 王芳珍 《西北工业大学学报》 EI CAS CSCD 北大核心 2024年第5期866-874,共9页
针对滚动轴承故障诊断在小样本环境下引起的模型泛化能力差、诊断精度低的问题,提出一种基于格拉姆角分场(GADF)和连续小波变化(continuous wavelet transform,CWT)与并行二维组归一化卷积神经网络(parallel convolutional neural netwo... 针对滚动轴承故障诊断在小样本环境下引起的模型泛化能力差、诊断精度低的问题,提出一种基于格拉姆角分场(GADF)和连续小波变化(continuous wavelet transform,CWT)与并行二维组归一化卷积神经网络(parallel convolutional neural network,P2D-GCNN)的滚动轴承故障诊断方法。对采集的数据进行预处理,采用格拉姆角场和连续小波变换将一维振动信号转换成二维图像作为模型输入,再选用数据增强技术扩充样本子图,满足网络输入要求,并将其导入搭建的组归一化卷积神经网络中进行诊断检测。结果表明:文中数据处理方法与搭建模型在小样本环境下泛化能力远高于SVM和1D-CNN等其他网络模型。为进一步验证模型在小样本数据下的识别能力,取数据集的70%,40%和20%样本量进行多次实验,所对应的训练准确率及测试准确率分为99.38%,99.02%,99.47%,98.29%,99.05%,97.08%。结果证明,文中模型在小样本环境下对轴承故障诊断具有很高的准确率。 展开更多
关键词 滚动轴承 故障诊断 格拉姆角分场(GADF) 小波变换(CWT) 并行二维卷积神经网络(P2D-GCNN)
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耐碱性阻燃超细纤维合成革贝斯的制备及性能
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作者 马春晖 王维 +3 位作者 宋兵 石海婷 王亮 徐志伟 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第10期117-125,共9页
为了解决阻燃水性聚氨酯在含浸应用中耐碱性差的问题,通过引入阻燃硅油改善阻燃水性聚氨酯的耐碱性,合成了一系列具备耐碱性的阻燃水性聚氨酯,结合湿法含浸的方式将其制备成阻燃超纤贝斯,然后对其耐碱、阻燃、力学及品质性能等进行了相... 为了解决阻燃水性聚氨酯在含浸应用中耐碱性差的问题,通过引入阻燃硅油改善阻燃水性聚氨酯的耐碱性,合成了一系列具备耐碱性的阻燃水性聚氨酯,结合湿法含浸的方式将其制备成阻燃超纤贝斯,然后对其耐碱、阻燃、力学及品质性能等进行了相关分析测试,协同阻燃后整理工艺,通过含浸磷氮型的阻燃剂确定了一款综合性能较佳的阻燃超纤贝斯的工艺配方。结果表明,阻燃硅油的引入可以有效改善阻燃水性聚氨酯及阻燃超纤贝斯的耐碱性。随着阻燃含磷二醇的加入,超纤贝斯的水平燃烧速率从121.37 mm/min降低至61.15 mm/min,较未阻燃降低了49.62%,LOI从18.8%提高至23.8%,较未阻燃提高了26.60%。通过含浸磷氮型阻燃剂进行阻燃后整理,LOI最高可达33.4%。为耐碱性阻燃超纤贝斯的制备提供了新思路。 展开更多
关键词 水性聚氨酯 阻燃 超纤贝斯 含浸
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生物质和塑料加氢脱氧制备燃料和化学品的双金属催化剂研究进展
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作者 刘露杰 刘奔 +4 位作者 中川善直 刘斯宝 王亮 藪下瑞帆 冨重圭一 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第7期1-31,共31页
在全球致力于实现碳中和的大背景下,生物质和废弃塑料的高值化利用已成为科研领域的研究热点.加氢脱氧反应(HDO),作为实现这一目标的重要途径之一,通过精准解离C-O/C-C键,为生产燃料和化学品提供了有效方法.在HDO过程中,C-O键的氢解及... 在全球致力于实现碳中和的大背景下,生物质和废弃塑料的高值化利用已成为科研领域的研究热点.加氢脱氧反应(HDO),作为实现这一目标的重要途径之一,通过精准解离C-O/C-C键,为生产燃料和化学品提供了有效方法.在HDO过程中,C-O键的氢解及不饱和键的氢化是主要步骤,而C-C键的氢解则是需要避免的副反应.与简单的氢化反应相比,HDO过程需要具有双功能特性的催化剂,特别是当目标产物为含氧化合物时,催化剂的区域选择性至关重要.近年来,双金属催化剂在生物质及其衍生物以及含氧塑料废弃物和聚合物的HDO过程中的应用受到广泛关注.通过深入理解金属纳米颗粒与金属氧化物之间的协同作用和强相互作用,双金属催化剂的理性设计取得了显著进展.特别是,部分金属氧化物(如ReO_(x),WO_(x),MoO_(x),FeO_(x))与贵金属(如Ir,Pt,Ru)之间存在的强相互作用,不仅促进了C-O键的断裂,还有效保留了C-C键,为催化剂的高活性和高选择性奠定了基础.通过调整催化剂组成、使用小比表面积的载体等方法,可以进一步优化催化剂性能.本综述聚焦于金属氧化物改性的贵金属催化剂在HDO反应中的最新研究进展,特别是总结了Ir、Pt和Ru基催化剂在HDO反应中的应用.由于这类催化剂的结构和性能能够精确控制,并且每种催化剂都具备独特的选择性,因此被广泛应用于生物质衍生物和塑料废弃物的HDO过程中.本文总结了双金属催化剂的结构特点、HDO反应机制、催化剂结构与催化性能之间的关联,以及这些催化剂在高附加值化学品生产中的实际应用.我们以甘油和1,2-丙二醇的氢解为模型反应,深入探讨了基于Ir、Pt和Ru的双金属催化剂的催化性能、结构特点和催化机理.这些催化剂在温和条件下实现了高效的氢脱氧反应,有效抑制了C-C键的断裂,并优化了化学选择性和区域选择性.双金属催化剂在生物质精炼和塑料/聚合物转化方面展现出广泛的适用性.本文还介绍了其在木质纤维素衍生原料、羰基化合物以及聚碳酸酯等塑料中的应用.然而,双金属催化剂的稳定性在实际应用中仍面临挑战,如金属烧结、浸出、积碳及金属-金属氧化物界面的重构等问题.因此,未来的研究重点是开发高效的再生方法和高度稳定的催化剂.综上所述,金属氧化物改性的贵金属催化剂在HDO反应中展现出巨大潜力.通过深入研究和优化,有望为生物质和塑料的高值化利用提供有效解决方案.本文旨在为双金属催化剂的理性设计和优化提供参考,以期推动生物质和塑料的高值化利用技术的进一步发展和应用. 展开更多
关键词 加氢脱氧 氢解 双金属催化剂 生物质衍生物 塑料废弃物
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Gastric cancer liver metastasis will reduce the efficacy of immunotherapy 被引量:2
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作者 liang wang Shan-Shan Liu +6 位作者 Sheng-Mei Zhang Xiao-Qian Chen Tao Huang Rong Tian Ya-Qi Zhao Zhou Chen Cai-Rang Xianba 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第9期2760-2764,共5页
Immune checkpoint inhibitors augment the antitumor activity of T cells by inhibiting the negative regulatory pathway of T cells,leading to notable efficacy in patients with non-small cell lung cancer,melanoma,and othe... Immune checkpoint inhibitors augment the antitumor activity of T cells by inhibiting the negative regulatory pathway of T cells,leading to notable efficacy in patients with non-small cell lung cancer,melanoma,and other malignancies through immunotherapy utilization.However,secondary malignant liver tumors not only lower the liver's sensitivity to immunotherapy but also trigger systemic immune suppression,resulting in reduced overall effectiveness of immune therapy.Patients receiving immunotherapy for non-small cell lung cancer and melanoma experience reduced response rates,progression-free survival,and overall survival when secondary malignant tumors develop in the liver.Through Liu's retrospective analysis,valuable insights are provided for the future clinical management of these patients.Therefore,in patients with gastric cancer(GC),the occurrence of liver metastasis might be indicative of reduced efficacy of immuno-therapy.Overcoming liver immune tolerance mechanisms and their negative impacts allows for the potential benefits of immunotherapy in patients with GC and liver metastasis.INTRODUCTION Gastric cancer(GC)ranks among the prevalent malignancies affecting the digestive system globally.Based on the latest epidemiological data[1,2],it holds the fifth position for incidence and the fourth position for mortality among all malignant tumors.GC cases and fatalities in China make up roughly half of the worldwide figures.Earlier investigations[3]have demonstrated that the median overall survival(mOS)among advanced GC patients left untreated typically ranges from 3 to 4 months.Systemic chemotherapy recipients often experience a mOS of around one year,accompanied by a marked improvement in the quality of life among patients with advanced GC.The mainstay of treatment for advanced GC patients involves chemotherapeutic medications such as fluoropyrimidines,platinum compounds,and taxanes.However,their efficacy in tumor control is constrained by acquired resistance and primary resistance.The rise of personalized precision therapy has propelled immunotherapy into the spotlight as a crucial component of comprehensive treatment[4].By blocking the negative regulatory pathways of T cells,immune checkpoint inhibitors(ICIs)boost the anti-tumor effect of T cells.Immunotherapy has brought about significant therapeutic benefits for patients diagnosed with non-small cell lung cancer,melanoma,and related illnesses[5,6],instilling newfound hope in those with advanced GC[7].However,phase III clinical trial data[8-12]reveals that the incorporation of immunotherapy into chemotherapy regimens improves overall survival(OS)outcomes for patients with advanced GC.The liver's immune-exempt nature renders it less responsive to immunotherapy when secondary malignant tumors are present,fostering systemic immune suppression and yielding unfavorable outcomes in immune therapy[13-15].In retrospective research[16-20]pertaining to non-small cell lung cancer and melanoma,it has been observed that the presence of secondary liver malignancies may lower the response rate,progression-free survival(PFS),and OS rates in patients treated with immunotherapy,independent of factors such as tumor mutation burden and PD-L1 expression.Despite this,there is a paucity of studies examining whether the existence of secondary malignant liver tumors affects the effectiveness of immunotherapy in patients diagnosed with advanced HER-2 negative GC. 展开更多
关键词 Immune checkpoint inhibitors Gastric cancer Gastric cancer with liver metastasis IMMUNOTHERAPY Liver immune tolerance
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A stable implicit nodal integration-based particle finite element method(N-PFEM)for modelling saturated soil dynamics 被引量:1
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作者 liang wang Xue Zhang +1 位作者 Jingjing Meng Qinghua Lei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2172-2183,共12页
In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated soils.Our approach incorporates the nodal integration technique into a gene... In this study,we present a novel nodal integration-based particle finite element method(N-PFEM)designed for the dynamic analysis of saturated soils.Our approach incorporates the nodal integration technique into a generalised Hellinger-Reissner(HR)variational principle,creating an implicit PFEM formulation.To mitigate the volumetric locking issue in low-order elements,we employ a node-based strain smoothing technique.By discretising field variables at the centre of smoothing cells,we achieve nodal integration over cells,eliminating the need for sophisticated mapping operations after re-meshing in the PFEM.We express the discretised governing equations as a min-max optimisation problem,which is further reformulated as a standard second-order cone programming(SOCP)problem.Stresses,pore water pressure,and displacements are simultaneously determined using the advanced primal-dual interior point method.Consequently,our numerical model offers improved accuracy for stresses and pore water pressure compared to the displacement-based PFEM formulation.Numerical experiments demonstrate that the N-PFEM efficiently captures both transient and long-term hydro-mechanical behaviour of saturated soils with high accuracy,obviating the need for stabilisation or regularisation techniques commonly employed in other nodal integration-based PFEM approaches.This work holds significant implications for the development of robust and accurate numerical tools for studying saturated soil dynamics. 展开更多
关键词 Particle finite element method Nodal integration Dynamic saturated media Second-order cone programming(SOCP)
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Carbon emission reduction:Contribution of photovoltaic power and practice in China 被引量:1
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作者 liang wang Li-qiong Jia +2 位作者 Geng Xie Xi-jie Chen Yang Liu 《China Geology》 CAS CSCD 2024年第2期371-376,共6页
As a clean and renewable form of energy,photovoltaic(PV)power generation converts solar energy into electrical energy,reducing the consumption of fossil fuels and significantly lowering greenhouse gas emissions.Amidst... As a clean and renewable form of energy,photovoltaic(PV)power generation converts solar energy into electrical energy,reducing the consumption of fossil fuels and significantly lowering greenhouse gas emissions.Amidst the global transition towards cleaner forms of energy,countries all around the world are vigorously developing PV technology. 展开更多
关键词 CONVERT POWER EMISSIONS
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并联压缩机系统变工况运行负荷分配研究
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作者 罗金平 黄景聪 +3 位作者 田盛 王亮 宋锋 刘立军 《风机技术》 2024年第5期73-77,共5页
为实现变工况下并联压缩机系统的高效稳定运行,本文建立了并联压缩机及负荷管网系统模型,定义了系统运行效率,并以此为指标对并联压缩机系统运行状态优劣进行定量评价。以实现并联压缩机系统最高运行效率为目标,提出了该系统变工况运行... 为实现变工况下并联压缩机系统的高效稳定运行,本文建立了并联压缩机及负荷管网系统模型,定义了系统运行效率,并以此为指标对并联压缩机系统运行状态优劣进行定量评价。以实现并联压缩机系统最高运行效率为目标,提出了该系统变工况运行状态下的负荷分配策略。通过运行实例分析,研究了变工况条件下并联压缩机组系统效率变化规律与最优调控策略。本文所提出的调控策略为拓展并联压缩机系统高效运行工况范围,提升系统运行效率提供了理论与技术支撑。 展开更多
关键词 并联压缩机系统 变工况运行 负荷分配
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Chemically bonded BiVO_(4)/Bi_(19)Cl_(3)S_(27) heterojunction with fast hole extraction dynamics for continuous CO_(2) photoreduction 被引量:2
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作者 Baojing Huang Xinxin Fu +5 位作者 Kai wang liang wang Hualei Zhang Zhongyi Liu Bin Liu Jun Li 《Advanced Powder Materials》 2024年第1期13-21,共9页
Surface charge localization and inferior charge transfer efficiency seriously restrict the supply of reactive hydrogen and the reaction dynamics of CO_(2) photoreduction performance of photocatalysts.Herein,chemically... Surface charge localization and inferior charge transfer efficiency seriously restrict the supply of reactive hydrogen and the reaction dynamics of CO_(2) photoreduction performance of photocatalysts.Herein,chemically bonded BiVO_(4)/Bi_(19)Cl_(3)S_(27)(BVO/BCS)S-scheme heterojunction with a strong internal electric field is designed.Experimental and density function theory calculation results confirm that the elaborated heterojunction accelerates the vectorial migration of photogenerated charges from BiVO_(4) to Bi_(19)Cl_(3)S_(27) via the interfacial chemical bonding interactions(i.e.,Bi-O and Bi-S bonds)between Bi atoms of BVO and S atoms of BCS or Bi atoms of BCS and O atoms of BVO under light irradiation,breaking the interfacial barrier and surface charge localization of Bi_(19)Cl_(3)S_(27),and further decreasing the energy of reactive hydrogen generation,CO_(2) absorption and activation.The separation efficiency of photogenerated carriers is much more efficient than that counterpart individual in BVO/BCS S-scheme heterojunction system.As a result,BVO/BCS heterojunction exhibits a significantly improved continuous photocatalytic performance for CO_(2) reduction and the 24 h CO yield reaches 678.27μmol⋅g^(-1).This work provides an atomic-level insight into charge transfer kinetics and CO_(2) reduction mechanism in S-scheme heterojunction. 展开更多
关键词 Extraction dynamics Activated hydrogen Interfacial chemical bonds S-scheme CO_(2)photoreduction
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Confirmation of a Sub-Saturn-size Transiting Exoplanet Orbiting a G Dwarf:TOI-1194 b and a Very Low Mass Companion Star: TOI-1251 B from TESS
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作者 Jia-Qi wang Xiao-Jun Jiang +18 位作者 Jie Zheng Hanna Kellermann Arno Riffeser liang wang Karen A.Collins Allyson Bieryla Lars A.Buchhave Steve B.Howell Elise Furlan Eric Girardin Joao Gregorio Eric Jensen Felipe Murgas Mesut Yilmaz Sam Quinn Xing Gao Ruo-Yu Zhou Frank Grupp Hui-Juan wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期129-143,共15页
We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 B.Exoplanet candidates... We report the confirmation of a sub-Saturn-size exoplanet,TOI-1194 b,with a mass of about 0.456+0.055-0.051M_(J),and a very low mass companion star with a mass of about 96.5±1.5 MJ,TOI-1251 B.Exoplanet candidates provided by the Transiting Exoplanet Survey Satellite(TESS)are suitable for further follow-up observations by ground-based telescopes with small and medium apertures.The analysis is performed based on data from several telescopes worldwide,including telescopes in the Sino-German multiband photometric campaign,which aimed at confirming TESS Objects of Interest(TOIs)using ground-based small-aperture and medium-aperture telescopes,especially for long-period targets.TOI-1194 b is confirmed based on the consistent periodic transit depths from the multiband photometric data.We measure an orbital period of 2.310644±0.000001 days,the radius is 0.767+0.045-0.041RJ and the amplitude of the RV curve is 69.4_(-7.3)^(+7.9)m s^(-1).TOI-1251 B is confirmed based on the multiband photometric and high-resolution spectroscopic data,whose orbital period is 5.963054+0.000002-0.000001days,radius is 0.947+0.035-0.033 R_(J) and amplitude of the RV curve is 9849_(-40)^(+42)ms^(-1). 展开更多
关键词 planets and satellites fundamental parameters-planets and satellites gaseous planets-stars fundamental parameters-stars low-mass-methods data analysis-techniques photometric-techniques spectroscopic
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Heavy ion energy influence on multiple-cell upsets in small sensitive volumes:from standard to high energies
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作者 Yang Jiao Li-Hua Mo +10 位作者 Jin-Hu Yang Yu-Zhu Liu Ya-Nan Yin liang wang Qi-Yu Chen Xiao-Yu Yan Shi-Wei Zhao Bo Li You-Mei Sun Pei-Xiong Zhao Jie Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第5期109-121,共13页
The 28 nm process has a high cost-performance ratio and has gradually become the standard for the field of radiation-hardened devices.However,owing to the minimum physical gate length of only 35 nm,the physical area o... The 28 nm process has a high cost-performance ratio and has gradually become the standard for the field of radiation-hardened devices.However,owing to the minimum physical gate length of only 35 nm,the physical area of a standard 6T SRAM unit is approximately 0.16μm^(2),resulting in a significant enhancement of multi-cell charge-sharing effects.Multiple-cell upsets(MCUs)have become the primary physical mechanism behind single-event upsets(SEUs)in advanced nanometer node devices.The range of ionization track effects increases with higher ion energies,and spacecraft in orbit primarily experience SEUs caused by high-energy ions.However,ground accelerator experiments have mainly obtained low-energy ion irradiation data.Therefore,the impact of ion energy on the SEU cross section,charge collection mechanisms,and MCU patterns and quantities in advanced nanometer devices remains unclear.In this study,based on the experimental platform of the Heavy Ion Research Facility in Lanzhou,low-and high-energy heavy-ion beams were used to study the SEUs of 28 nm SRAM devices.The influence of ion energy on the charge collection processes of small-sensitive-volume devices,MCU patterns,and upset cross sections was obtained,and the applicable range of the inverse cosine law was clarified.The findings of this study are an important guide for the accurate evaluation of SEUs in advanced nanometer devices and for the development of radiation-hardening techniques. 展开更多
关键词 28 nm static random access memory(SRAM) Energy effects Heavy ion Multiple-cell upset(MCU) Charge collection Inverse cosine law
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Experimental study on permeability evolution of deep high-stressed coal under major horizontal stress unloading paths
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作者 Chao Liu Jiahao Zhang +3 位作者 Songwei Wu Jinghua Qi Beichen Yu liang wang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第11期1495-1508,共14页
Both bulk stress(σ_(i i))and stress path(SP)significantly affect the transportation characteristics of deep gas during reservoir pressure depletion.Therefore,the experimental study of horizontal stress unloading on s... Both bulk stress(σ_(i i))and stress path(SP)significantly affect the transportation characteristics of deep gas during reservoir pressure depletion.Therefore,the experimental study of horizontal stress unloading on seepage behavior of gas-bearing coal under constantσi i-constraints is performed.The results show that coal permeability is affected by horizontal stress anisotropy(σ_(H)≠σh),and the contribution of minor horizontal stress to permeability is related to the differential response of horizontal strain.The slippage phenomenon is prominent in deep high-stress regime,especially in low reservoir pressure.σ_(i i)and SP jointly determine the manifestation of slippage effect and the strength of stress sensitivity(γ)of permeability.Deep reservoir implies an incremental percentage of slip-based permeability,and SP weakens the slippage effect by changing the elastic–plastic state of coal.However,γis negatively correlated with slippage effect.From the Walsh model,narrow(low aspect-ratio)fractures within the coal under unloading SP became the main channel for gas seepage,and bring the effective stress coefficient of permeability(χ)less than 1 for both low-stress elastic and high-stress damaged coal.With the raise of the effective stress,the effect of pore-lined clay particles on permeability was enhanced,inducing an increase inχfor highstress elastic coal. 展开更多
关键词 True triaxial stress path Constant bulk stress Horizontal stress Effective stress coefficient of permeability Slippage effect
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Dynamics modeling and optimal control for multi-information diffusion in Social Internet of Things
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作者 Yaguang Lin Xiaoming wang +1 位作者 liang wang Pengfei Wan 《Digital Communications and Networks》 SCIE CSCD 2024年第3期655-665,共11页
As an ingenious convergence between the Internet of Things and social networks,the Social Internet of Things(SIoT)can provide effective and intelligent information services and has become one of the main platforms for... As an ingenious convergence between the Internet of Things and social networks,the Social Internet of Things(SIoT)can provide effective and intelligent information services and has become one of the main platforms for people to spread and share information.Nevertheless,SIoT is characterized by high openness and autonomy,multiple kinds of information can spread rapidly,freely and cooperatively in SIoT,which makes it challenging to accurately reveal the characteristics of the information diffusion process and effectively control its diffusion.To this end,with the aim of exploring multi-information cooperative diffusion processes in SIoT,we first develop a dynamics model for multi-information cooperative diffusion based on the system dynamics theory in this paper.Subsequently,the characteristics and laws of the dynamical evolution process of multi-information cooperative diffusion are theoretically investigated,and the diffusion trend is predicted.On this basis,to further control the multi-information cooperative diffusion process efficiently,we propose two control strategies for information diffusion with control objectives,develop an optimal control system for the multi-information cooperative diffusion process,and propose the corresponding optimal control method.The optimal solution distribution of the control strategy satisfying the control system constraints and the control budget constraints is solved using the optimal control theory.Finally,extensive simulation experiments based on real dataset from Twitter validate the correctness and effectiveness of the proposed model,strategy and method. 展开更多
关键词 Social Internet of Things Information diffusion Dynamics modeling Trend prediction Optimal control
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Optimizing the power conversion processes in diluted donor/acceptor heterojunctions towards 19.4%efficiency all-polymer solar cells
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作者 liang wang Chen Chen +11 位作者 Zirui Gan Chenhao Liu Chuanhang Guo Weiyi Xia Wei Sun Jingchao Cheng Yuandong Sun Jing Zhou Zexin Chen Dan Liu Wei Li Tao wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期345-350,共6页
All polymer solar cells(all-PSCs)promise mechanically-flexible and morphologically-stable organic photovoltaics and have aroused increased interests very recently.However,due to their disorderly conformation structure... All polymer solar cells(all-PSCs)promise mechanically-flexible and morphologically-stable organic photovoltaics and have aroused increased interests very recently.However,due to their disorderly conformation structures within the photoactive film,inefficient charge generation and carrier transport are observed which lead to inferior photovoltaic performance compared to smaller molecular acceptor-based photovoltaics.Here,by diluting PM6 with a cutting-edge polymeric acceptor PY-IT and diluting PY-IT with PM6 or D18,donor-dominating or acceptor-dominating heterojunctions were prepared.Synchrotron X-ray and multiple spectrometer techniques reveal that the diluted heterojunctions receive increased structural order,translating to enhanced carrier mobility,improved exciton diffusion length,and suppressed non-radiative recombination loss during the power conversion.As the results,the corresponding PM6+1%PY-IT/PY-IT+1%D18 and PM6+1%PY-IT/PY-IT+1%PM6 devices fabricated by layer-by-layer deposition received superior power conversion efficiency(PCE)of 19.4%and 18.8%respectively,along with enhanced operational lifetimes in air,outperforming the PCE of 17.5%in the PM6/PY-IT reference device. 展开更多
关键词 All-polymer solar cells Power conversion efficiency Structural order Charge generation
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