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FlowDNN:a physics-informed deep neural network for fast and accurate flow prediction

Frontiers of Information Technology & Electronic Engineering 2022年第2期23卷 207-219页

作者： Donglin CHEN Xiang GAO chuanfu xu Siqi WANG Shizhao CHEN Jianbin FANG Zheng WANG College of Computer National University of Defense TechnologyChangsha 410073China State Key Laboratory of High Performance Computing National University of Defense TechnologyChangsha 410073China School of Computing University of LeedsLeeds LS29JTUK

For flow-related design optimization problems,e.g.,aircraft and automobile aerodynamic design,computational fluid dynamics(CFD)simulations are commonly used to predict flow fields and analyze performance.While important,CFD simulations are a resource-demanding and time-consuming iterative process.The expensive simulation overhead limits the opportunities for large design space exploration and prevents interactive design.In this paper,we propose Flow DNN,a novel deep neural network(DNN)to efficiently learn flow representations from CFD results.Flow DNN saves computational time by directly predicting the expected flow fields based on given flow conditions and geometry shapes.Flow DNN is the first DNN that incorporates the underlying physical conservation laws of fluid dynamics with a carefully designed attention mechanism for steady flow prediction.This approach not only improves the prediction accuracy,but also preserves the physical consistency of the predicted flow fields,which is essential for CFD.Various metrics are derived to evaluate Flow DNN with respect to the whole flow fields or regions of interest(RoIs)(e.g.,boundary layers where flow quantities change rapidly).Experiments show that Flow DNN significantly outperforms alternative methods with faster inference and more accurate results.It speeds up a graphics processing unit(GPU)accelerated CFD solver by more than 14000×,while keeping the prediction error under 5%.

关键词： Deep neural network Flow prediction Attention mechanism Physics-informed loss

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Optimization of a global seventh-order dissipative compact finite-difference scheme by a genetic algorithm

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Applied Mathematics and Mechanics(English Edition) 2018年第11期39卷 1679-1690页

作者： Yu LIN Yaming CHEN chuanfu xu Xiaogang DENG College of Computer National University of Defense Technology College of Aerospace Science and Engineering National University of Defense Technology State Key Laboratory of High Performance Computing National University of Defense Technology

A global seventh-order dissipative compact finite-difference scheme is optimized in terms of time stability. The dissipative parameters appearing in the boundary closures are assumed to be different, resulting in an optimization problem with several parameters determined by applying a generic algorithm. The optimized schemes are analyzed carefully from the aspects of the eigenvalue distribution, the ε-pseudospectra, the short time behavior, and the Fourier analysis. Numerical experiments for the Euler equations are used to show the effectiveness of the final recommended scheme.

关键词： high-order dissipative compact finite-difference scheme genetic algorithm time stable

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面向多核CPU/众核GPU架构的非结构CFD共享内存并行计算技术

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航空学报 2024年第7期45卷 108-121页

作者：张健李瑞田邓亮代喆刘杰徐传福国防科技大学并行与分布计算全国重点实验室长沙410073 中国空气动力研究与发展中心计算空气动力研究所绵阳621000

针对现代高性能计算机架构开展非结构CFD节点内共享内存并行,是提升浮点计算效率、实现更大规模流体仿真应用能力的关键。然而由于非结构网格CFD计算存在拓扑关系复杂、数据局部性差、数据写冲突等问题,传统算法如何共享内存并行化以高... 详细信息

针对现代高性能计算机架构开展非结构CFD节点内共享内存并行,是提升浮点计算效率、实现更大规模流体仿真应用能力的关键。然而由于非结构网格CFD计算存在拓扑关系复杂、数据局部性差、数据写冲突等问题,传统算法如何共享内存并行化以高效发挥多核CPU/众核GPU的硬件能力,成为一个重大的挑战。从一个工业级非结构CFD软件出发,通过深入分析其计算行为和访存模式,设计实现了多种共享内存并行算法,采用了网格重排序、循环融合、多级访存等数据局部性优化技术进一步提升性能。面向多核CPU架构,系统开展了循环级与任务级两种并行模式的对比研究;面向众核GPU架构,创新地提出了一种基于多级访存优化方法的规约并行策略。利用M6机翼和CHN-T1飞机算例对所有并行算法及优化技术进行了全面验证与评估。结果表明:在多核CPU平台上,基于剖分复制的任务级并行策略性能最好,采用Cuthill-McKee重排序以及循环融合分别使整体性能提升10%。在众核GPU平台上,基于多级访存的规约策略具有显著的加速效果,优化后热点函数的性能相比优化前提升了3倍,相比CPU串行性能整体加速比可达127。

关键词：非结构网格 CFD 共享内存并行 GPU 访存优化

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菇渣有机肥配施脱硫石膏对黄河三角洲盐碱土活性有机碳及其敏感性的影响

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水土保持学报 2024年第2期38卷 387-397页

作者：李传福徐家林明玉飞高舒吕欣杨宇轩李永强焦树英山东农业大学资源与环境学院土肥高效利用国家工程研究中心山东泰安271018 德州市园林绿化服务中心山东德州253000

[目的]为探讨菇渣有机肥与脱硫石膏对盐碱土有机碳组分及碳库管理指数的影响。[方法]以黄河三角洲新垦殖小麦-玉米轮作地为研究对象,采用随机区组试验方法,设置不施肥(CK)、农民常用施肥(CN)、菇渣有机肥(MCOF)、菇渣有机肥+脱硫石膏(MC... 详细信息

[目的]为探讨菇渣有机肥与脱硫石膏对盐碱土有机碳组分及碳库管理指数的影响。[方法]以黄河三角洲新垦殖小麦-玉米轮作地为研究对象,采用随机区组试验方法,设置不施肥(CK)、农民常用施肥(CN)、菇渣有机肥(MCOF)、菇渣有机肥+脱硫石膏(MCOG)4个处理,通过3年田间施肥处理。[结果]菇渣有机肥与脱硫石膏配施显著降低0-20 cm土壤盐碱度,提高土壤氮磷钾养分含量和阳离子交换量(p<0.05);各处理0-20 cm土层总有机碳(TOC)、易氧化有机碳(EOC)、微生物量碳(MBC)含量高于20-40 cm土层,而水溶性有机碳(WSOC)含量则相反;与CN处理相比,MCOG处理0-20 cm土层TOC、EOC、WSOC、MBC分别显著提高15.48%,23.50%,18.98%,51.40%,EOC和MBC有效率分别提高13.94%,30.49%,且MCOG处理较CN和CK处理的土壤碳库管理指数(CPMI)显著提高15.38%和20.00%;MBC的敏感性指数均高于其他有机碳组分,MCOG处理MBC值最高。相关性分析表明,土壤TOC含量取决于其活性组分,而影响盐碱土有机碳活性组分含量及其有效率、碳库管理指数的主要因素为pH、CEC和EC。[结论]菇渣有机肥与脱硫石膏配施能显著降低土壤盐碱含量,提高土壤肥力并增强固碳效率,研究结果为拓展盐碱地土壤有机改良方法提供理论依据和数据支撑。

关键词：盐碱地菇渣有机肥脱硫石膏活性有机碳碳库管理指数

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Overview and prospects of food biosafety

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Journal of Biosafety and Biosecurity 2022年第2期4卷 146-150页

作者： Xiaofeng Hua Baichuan xu Yang Xiao Shengnan Liang chuanfu Zhang Hongbin Song Chinese PLA Center for Disease Control and Prevention BeijingChina Army Medical University ChongqingChina

Biosafety issues have become a major threat to the health of humans,animals,and ecosystems worldwide.As problems with food production and the food supply chain have become of greater concern to consumers,issues involving biosafety and food safety from a developmental perspective need to be urgently addressed.The term,food biosafety,is the combination of the core concepts of biosafety and food safety.It refers to the effective prevention of biological threats to food production and the food supply chain by controlling foodborne diseases arising from the consumption of edible plants and animal products,by preventing the establishment of invasive species,by strictly controlling the use of antibiotics,agricultural chemicals and veterinary drugs in the food supply chain,and by initiating food defense and anti-terrorism measures to protect the health of humans,animals,and ecosystems,thereby maintaining sustainable development in China.This article provides theoretical support for the extension of food biosafety to propose an innovative plan for the international co-governance of food safety.

关键词： Dual-use technologies Biosafety Food safety

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Acupuncture inhibits cue-induced heroin craving and brain activation

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Neural Regeneration Research 2012年第33期7卷 2607-2616页

作者： Xinghui Cai Xiaoge Song chuanfu Li Chunsheng xu Xiliang Li Qi Lu School of Acupuncture and Orthopedics Anhui University of Traditional Chinese Medicine Hefei 230038 Anhui Province China Institute of Acupuncture and Meridians Anhui University of Traditional Chinese Medicine Hefei 230038 Anhui Province China Medical Imaging Center First Affiliated Hospital of Anhui University of Traditional Chinese Medicine Hefei 230031 Anhui Province China

Previous research using functional MRI has shown that specific brain regions associated with drug dependence and cue-elicited heroin craving are activated by environmental cues. Craving is an important trigger of heroin relapse, and acupuncture may inhibit craving. In this study, we performed functional MRI in heroin addicts and control subjects. We compared differences in brain activation between the two groups during heroin cue exposure, heroin cue exposure plus acupuncture at the Zusanli point （ST36） without twirling of the needle, and heroin cue exposure plus acupuncture at the Zusanli point with twirling of the needle. Heroin cue exposure elicited significant activation in craving-related brain regions mainly in the frontal lobes and callosal gyri. Acupuncture without twirling did not significantly affect the range of brain activation induced by heroin cue exposure, but significantly changed the extent of the activation in the heroin addicts group. Acupuncture at the Zusanli point with twirling of the needle significantly decreased both the range and extent of activation induced by heroin cue exposure compared with heroin cue exposure plus acupuncture without twirling of the needle. These experimental findings indicate that presentation of heroin cues can induce activation in craving-related brain regions, which are involved in reward, learning and memory, cognition and emotion. Acupuncture at the Zusanli point can rapidly suppress the activation of specific brain regions related to craving, supporting its potential as an intervention for drug craving.

关键词： acupuncture Zusanli （ST36） heroin addiction cues induction functional MRI craving twirling activation of brain regions traditional Chinese medicine neural regeneration

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THIOUREA LEACHING OF GOLD FROM A CALCINE OF GOLD-BEARING ARSENICAL PYRITE CONCENTRATE

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Transactions of Nonferrous Metals Society of China 1996年第1期6卷 21-24页

作者： xu Shengming Zhang chuanfu Zhao Tiancong Wu Yanjun Department of Nonferrous Metallurgy Central South University of Technology Changsha 410083 Department of Chemistry Hunan School of Agricultural MechanizationChangsha 410126

The thiourea leaching of gold from the calcine of gold-bearing arsenical pyrite concentrate of Kangjiawan mine was studied.The effects of the leaching time,the concentrations of thiourea,hydrochloric acid and initial ferric ion on the leaching recovery of gold were investigated,and a regressive model has been established,which showed that the concentrations of thiourea and hydrochloric acid were the most important factors,leaching time the second,and concentration of the initial ferric ion the least・Under the optimal conditions,that is,temperature 50℃,the ratio of liquid to solid 4:1,thiourea 12g/L,hydrochloric acid 1 mol/L,and initial ferric ion 1 g/L,the leaching recoveries of gold and silver were more than 81%and 73%,respectively.The increase of silver recovery and the reduction of thiourea consumption could be attained when sodium sulphite was added.

关键词： gold-bearing arsenical pyrite concentrate calcine thiourea leaching of gold

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基于支持向量回归的动网格技术研究

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空气动力学学报 2022年第5期40卷 146-157页

作者：高翔廖海翔徐传福国防科技大学计算机学院量子信息研究所兼高性能计算国家重点实验室长沙410073

为了提高动网格生成的计算效率,深入分析了广泛使用的径向基函数插值动网格方法,进一步放宽其贪心选点的约束条件,提出并完善了一种基于支持向量回归的高效动网格技术,并给出了该机器学习算法针对网格运动的适配方案。基于基准案例的三... 详细信息

为了提高动网格生成的计算效率,深入分析了广泛使用的径向基函数插值动网格方法,进一步放宽其贪心选点的约束条件,提出并完善了一种基于支持向量回归的高效动网格技术,并给出了该机器学习算法针对网格运动的适配方案。基于基准案例的三套疏密网格和四类运动形式,对不同径向基核函数的拟合性能进行了全面测试分析。以前期采用的高斯核函数方法为基准,进一步通过典型动网格案例,量化对比了筛选出的核函数在网格变形质量、计算效率和参数设置等方面的能力。结果表明基于CP C~2和IMQB核函数支持向量回归的动网格方法具有良好的变形能力和计算效率。

关键词：动网格网格变形支持向量回归径向基函数

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Catalyst design strategies towards highly shape-selective HZSM-5 for paraxylene through toluene alkylation

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Green Energy & Environment 2020年第4期5卷 385-393页

作者： Xin Huang Ruizhuang Wang xu Pan chuanfu Wang Maohong Fan Yufei Zhu Yonggang Wang Jin Peng National Institute of Clean-and-low-carbon Energy(NICE) BeijingChina School of Chemical and Environmental Engineering China University of Mining and TechnologyBeijingChina Departments of Petroleum and Chemical Engineering University of WyomingLaramieWYUSA China Pingmei Shenma Group PingdingshanChina

With the shape selective zeolite catalyst,toluene alkylation with methanol to para-xylene(MTPX)technology could produce highly pure para-xylene(PX)in one step.The lower feedstock cost and less energy consumption in products separation make it more competitive compared to the current toluene disproportionation route.Thus,MTPX is regarded as the most reasonable production route for PX production.This article reviews the strategies that applied to the preparation of high-performance catalysts for MTPX,with special focus on the precise control of pore dimension and acid sites distribution in zeolite to achieve the highest selectivity to PX.The outlook of the MTPX catalyst is also proposed to guide the catalyst development in the field.

关键词： Toluene Methanol Para-xylene ZSM-5 Alkylation

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Research on Thermal Deep-drawing Technology of Magnesium Alloy (AZ31B) Sheets

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Journal of Materials Science & Technology 2004年第2期20卷 153-156页

作者： Shihong ZHANG, Kun ZHANG, Zhongtang WANG, chuanfu YU, Yi xu and Qiang WANGInstitute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

Forming technology of Mg alloy (AZ31B) sheets can be investigated by thermal deep drawing experiments. In the experiments, the blank holder and die contacting with the blank were heated to the same temperature as the blank by using the heating facility. The circular blank heated in an oven is formed at a temperature range of 100~400 ℃ to obtain the optimum forming temperature range and the effects of major technical parameters on the workpiece quality. It is found that the blank is brittle at temperatures lower than 200℃. Temperatures higher than 400℃ are not suitable for forming of the sheets because of severe oxidation and wrinkling. AZ31B shows an excellent formability at temperatures from 300 to 350℃ and can be formed into a workpiece with good quality. When the blank holder force is 9 kN, extruded sheets with a thickness of 1 mm can be formed into cups without wrinkling. Workpieces show strong anisotropic deformation behavior on the flanges.

关键词： Magnesium alloy (AZ31B) Thermal deep drawing Blank holder force Wrinkling

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