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GPU accelerated MFiX-DEM simulations of granular and multiphase flows

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Particuology 2022年第3期20卷 14-24页

作者： Liqiang lu National Energy Technology Laboratory MorgantownWV 26507United States Leidos Research Support Team MorgantownWV 26506United States

In this research,a Graphical Processing Unit(GPU)accelerated Discrete Element Method(DEM)code was developed and coupled with the Computational Fluid Dynamic(CFD)software MFiX to simulate granular and multiphase flows with heat transfers and chemical *** Fortran-based CFD solver was coupled with the CUDA/C++based DEM solver through inter-process *** speedup to the CPU version of MFiX-DEM is about 130-243 folds in the simulation of particle *** fluidized bed simulations,the DEM computation time is reduced from 91%to 17%with a speedup of 78 *** simulation of Geldart A particle fluidization revealed a similar level of importance of both fluid and particle *** filtered drag derived from the two-fluid model is suitable for Euler-Lagrangian simulations with both fluid and particle *** overcorrects the influence of sub-grid structures if used for simulations with only fluid coarse-graining.

关键词： GPU MFIX DEM Drag Fluidization

Large Eddy Simulation of Turbulent Channel Flows over Rough Walls with Stochastic Roughness Height Distributions

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Journal of Hydrodynamics 2020年第3期32卷 570-581页

作者： Hao lu China Key Laboratory of Enhanced Heat Transfer and Energy Conservation of Education Ministry School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China

This paper studies the 3-D turbulent channel flows over rough walls with stochastic roughness height distributions by using the large eddy simulation and the immersed boundary method. The obtained mean and fluctuating velocity profiles for the smooth and rough channel flows agree well with the available numerical and experimental results. The stochastic surface roughness is found to have a more significant influence than the uniform surface roughness on the turbulent velocity statistics and the coherent structures, with the same average roughness height. With a greater variation in the roughness height, the mean velocity and the streamwise fluctuating velocity is decreased and the spanwise velocity and the wall-normal fluctuating velocity are increased. In addition, one observes larger and more profuse quasi-streamwise vortices, hairpin vortices and elongated structures above the crest plane of the roughness array in cases of highly stochastic rough walls. However, the low-speed streaky structures are broken up locally and the ejection and sweep events are depressed by the stochastic roughness below the average roughness height. The results of this study support Townsend’s wall-similarity hypothesis for both stochastic and uniform rough wall turbulences, demonstrating that in both cases the effects of the surface roughness on the turbulent flow are limited to the rough sub-layer.

关键词： Large eddy simulation turbulent channel flow rough wall stochastic roughness height

Application of buckling-restrained braces in the seismic control of suspension bridges

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Earthquake Engineering and Engineering Vibration 2022年第2期21卷 543-557页

作者： Long lu College of Environment and Civil Engineering Chengdu University of TechnologyChengdu 610059China

Buckling-restrained braces(BRBs)are widely used to improve the seismic performance of *** paper aims to introduce BRBs to suspension bridges and assess the seismic performance of bridges with *** the Dadu River Bridge as a case study,an FEA model of the bridge is established,and different seismic measures(BRBs between the deck and the tower,BRBs at the middle of the span to replace the inclined suspenders to connect the deck and the main cables,fluid viscous dampers(FVDs)between the deck and the tower,the combination of BRBs to replace the inclined suspenders as well as FVDs between the deck and the tower)are applied to the suspension *** influence of the parameters of BRBs on the seismic response of the suspension bridge is studied,and the performance of the bridge with BRBs is compared with that of the bridge with *** results indicate that the use of BRBs in place of the inclined suspenders is beneficial to reduce the displacement of the deck and limit the shear force and bending moment of the *** seismic performance of the suspension bridge with BRBs and FVDs is better than that of the bridge with BRBs or ***,the application of BRBs is a feasible method to improve the seismic performance of the suspension bridge.

关键词： buckling-restrained braces fluid viscous dampers suspension bridge seismic response earthquake

Advances in ethnopharmacology,phytochemistry and pharmacology of Erigerontis Herba and its Chinese medicine prescriptions

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Traditional Medicine Research 2025年第1期10卷 44-61页

作者： Yang Zhou Yuan-Yan Huang Ding-Yue Shang Ying Chen Meng Tian Cheng-Yu Jin Xin lu Bing-Chun Yan Han-Qing Pang Institute of Translational Medicine School of MedicineYangzhou UniversityYangzhou 225009China Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Diseases Yangzhou UniversityYangzhou 225009China School of Medicine Nanjing University of Chinese MedicineNanjing 210023China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Guangxi Normal UniversityGuiling 541004China.

Erigerontis Herba(EH),the dried whole plant of Erigeron breviscapus,is well-known for circulating blood,activating meridians to alleviate pain,expelling wind,and clearing away *** has been extensively utilized in southern China for the treatment of stroke hemiplegia,chest stuffiness and pains,rheumatic arthralgia,headache,and *** review focuses on the botany,ethnopharmacology,phytochemistry,pharmacology and toxicity of EH and its related prescriptions to offer new insights for prospective research of *** information about EH was retrieved from ancient records and books,PubMed,China National Knowledge Infrastructure,Chinese Pharmacopoeia,Web of Science,Doctoral and Master’s Theses,and various electronic *** is a member of Compositae family and is mainly grown in southern *** Chinese medicine records that EH has the effects of circulating blood and removing blood stasis,expelling wind,and removing cold,as well as relieving rigidity of muscle and relieving *** now,nearly 200 ingredients have been characterized from EH,including flavonoids,caffeoyls,aromatic acids,coumarins,pentacyclic terpenoids,volatile oil and other *** extracts,EH related prescriptions(Dengzhan Xixin injection,Dengzhan Shengmai capsules,etc.)or compounds(scutellarin,scutellarein,etc.)possessed obvious therapeutic effects of ischemic stroke,cerebral hemorrhage,myocardial infarction,Alzheimer’s disease,diabetes and its complications,gastric cancer,bone,and joint degenerative ***,the major active compound of EH,has been used as a quality *** no obvious toxicity of EH has been *** to its traditional applications,ethnopharmacology,phytochemistry,pharmacology,and toxicity,EH was applied as a valuable herb for clinical application in food and medicine *** several compounds have been shown to possess diverse biological activities,the underlying mechanisms of their actions remain *** fully exploi

关键词： Erigeron breviscapus traditional applications ethnopharmacology phytochemistry pharmacology

Leader-following consensus of second-order nonlinear multi-agent systems subject to disturbances

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Frontiers of Information Technology & Electronic Engineering 2019年第1期20卷 88-94页

作者： Mao-bin lu lu LIU School of Automation Beijing Institute of Technology City University of Hong Kong Shenzhen Research Institute Department of Biomedical Engineering City University of Hong Kong

In this study, we investigate the leader-following consensus problem of a class of heterogeneous secondorder nonlinear multi-agent systems subject to disturbances. In particular, the nonlinear systems contain uncertainties that can be linearly parameterized. We propose a class of novel distributed control laws, which depends on the relative state of the system and thus can be implemented even when no communication among agents exists. By Barbalat's lemma, we demonstrate that consensus of the second-order nonlinear multi-agent system can be achieved by the proposed distributed control law. The effectiveness of the main result is verified by its application to consensus control of a group of Van der Pol oscillators.

关键词： Multi-agent systems Leader-following consensus Distributed control

Disturbance observer-based backstepping control for hypersonic flight vehicles without use of measured flight path angle

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Chinese Journal of Aeronautics 2021年第2期34卷 396-406页

作者： Yao lu Beijing Aerospace Automatic Control Institute Beijing 100854China National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing 100854China

In this paper a nonlinear control method is proposed for the tracking control of hypersonic flight vehicles. The designed control laws do not utilize the measured flight path angle due to its inferior accuracy in practical engineering. For this, an estimated flight path angle is designed via the measurements of the altitude and velocity. A tracking differentiator is designed for constructing nonlinear disturbance observer which is used to estimate the model uncertainties including the parameter indeterminacies and external disturbances in the channels of velocity and pitch rate. A robust high-order differentiator is introduced to avoid the employment of the measured flight path angle and estimate the lumped disturbance in dynamics of flight path angle. Meanwhile, the possible saturation of the control inputs is considered and compensated by the auxiliary states. The boundness of closed-loop signals is proved through the Lyapunov theory. Comparative simulations are carried out and the results demonstrate the effectiveness of the proposed method.

关键词： Anti-saturation Backstepping Disturbance observer Flight control Hypersonic flight vehicle State estimation

山姜素调节cAMP/PKA/CREB信号通路促进骨质疏松性骨折大鼠骨折愈合

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中国组织工程研究 2025年第12期29卷 2438-2443页

作者：陆飞周静金涛连云港市第一人民医院康复医学科江苏省连云港市222000 南京医科大学康达学院康复医学部江苏省连云港市222000 中国人民解放军东部战区总医院健康医学科江苏省南京市210018

背景:山姜素具有抗炎、抗肿瘤、抗菌等作用,已被证实能够缓解骨质疏松症,但山姜素对骨质疏松性骨折的影响及机制仍不清楚。目的:探讨山姜素调节环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白信号通路对骨质疏松性骨折大鼠的改善作... 详细信息

背景:山姜素具有抗炎、抗肿瘤、抗菌等作用,已被证实能够缓解骨质疏松症,但山姜素对骨质疏松性骨折的影响及机制仍不清楚。目的:探讨山姜素调节环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白信号通路对骨质疏松性骨折大鼠的改善作用。方法:采用双侧卵巢切除手术构建骨质疏松症骨折大鼠模型,将成功造模大鼠依据随机数字表法分为山姜素低、中、高剂量组、抑制剂组和模型组,另选12只大鼠作为假手术组。骨折造模当天,山姜素低、中、高剂量组大鼠灌胃7.5,15,30 mg/kg的山姜素+腹腔注射等量的生理盐水,抑制剂组灌胃30 mg/kg的山姜素+腹腔注射5 mg/kg的H-89(通路抑制剂),模型组与假手术组给予(灌胃+腹腔注射)等量生理盐水,1次/d,连续8周。放射性检查评估大鼠骨折愈合情况并进行愈合评分;骨密度扫描仪测定骨折处骨密度;通过三点弯曲实验和压缩实验评估大鼠股骨生物力学状况;苏木精-伊红染色观察大鼠骨折处病理损伤;酶联免疫吸附(ELISA)法检测血清碱性磷酸酶、骨钙素和Ⅰ型胶原交联C-末端肽、环磷酸腺苷水平的变化;Western blot检测股骨组织中骨形态发生蛋白2和环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白通路蛋白表达。结果与结论:①相较于假手术组,模型组大鼠骨折愈合评分、骨密度、最大负荷、最大应力、碱性磷酸酶、骨钙素、环磷酸腺苷水平、骨形态发生蛋白2、磷酸化蛋白激酶A/蛋白激酶A、磷酸化环磷酸腺苷反应元件结合蛋白/环磷酸腺苷反应元件结合蛋白表达下降,Ⅰ型胶原交联羧基末端肽水平增加(P<0.05);与模型组比较,山姜素各剂量组大鼠上述各项指标呈现相反的变化(P<0.05);与山姜素高剂量组比较,抑制剂组大鼠上述指标变化均被逆转(P<0.05)。②结论:山姜素可能通过激活环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白信号通路加速骨质疏松症骨折大鼠的骨折愈合。

关键词：山姜素环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白骨质疏松骨折愈合大鼠

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农业“水-能源-粮食”系统协同的生态效应

生态经济 2025年第1期41卷 149-157页

作者：卢召艳黎红梅湖南农业大学经济学院湖南长沙410128

厘清农业“水—能源—粮食”系统协同的生态效应对于促进农业绿色低碳发展具有重要意义。为此,基于中国2000—2021年的省际面板数据,采用双向固定效应模型考察农业“水—能源—粮食”系统协同对农业生态环境的影响,而后构建中介效应模... 详细信息

厘清农业“水—能源—粮食”系统协同的生态效应对于促进农业绿色低碳发展具有重要意义。为此,基于中国2000—2021年的省际面板数据,采用双向固定效应模型考察农业“水—能源—粮食”系统协同对农业生态环境的影响,而后构建中介效应模型和调节效应模型进一步明晰二者间的作用机制。研究结果显示:(1)农业“水—能源—粮食”系统协同能够显著提高农业生态环境质量,且经过一系列稳健性检验后结论依然成立。(2)异质性分析表明,农业“水—能源—粮食”系统协同的生态效应在粮食主产区和中西部地区更加显著。(3)作用机制检验发现,农业“水—能源—粮食”系统协同主要通过规模化经营和种植结构调整提高农业生态环境质量,环境规制在农业“水—能源—粮食”系统协同的生态效应中产生正向调节作用。基于此,需建立以水资源节约集约利用为核心的粮食高质量发展机制;重视规模化经营及种植结构调整在提高农业生态环境质量中发挥的重要作用;积极探索差异化的区域农业“水—能源—粮食”协同政策;不断完善农业环保政策。

关键词：农业“水—能源—粮食”系统协同生态效应

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论苏轼的纪行组诗

海南大学学报（人文社会科学版） 2025年第1期43卷 8-15页

作者：路成文宋定坤华中科技大学人文学院湖北武汉430074

苏轼纪行组诗一百零六组,在文本形态、内容表现与风格特征三方面有显著的个人特色。这些组诗以记录行旅之间的单个事件为主,除纪行外,频繁叙及游览和社交。在宋诗重说理的风尚影响下,苏轼往往在纪行组诗中抒发一己之情感、阐发深刻的人... 详细信息

苏轼纪行组诗一百零六组,在文本形态、内容表现与风格特征三方面有显著的个人特色。这些组诗以记录行旅之间的单个事件为主,除纪行外,频繁叙及游览和社交。在宋诗重说理的风尚影响下,苏轼往往在纪行组诗中抒发一己之情感、阐发深刻的人生哲理。此外,他的纪行组诗不仅能突破传统纪行组诗对于诗人个体的关注,还能做到“情”“景”“事”“理”四者兼备,为唐宋纪行组诗的创作开辟新途。

关键词：苏轼纪行组诗文本形态内容表现风格特征

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