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Development of Residual Distribution Schemes for the Discontinuous Galerkin Method:The Scalar Case with Linear Elements

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Communications in Computational Physics 2009年第2期5卷 376-390页

作者： Remi Abgrall Chi-Wang shu Institut de Mathematiques and INRIA Universite Bordeaux I341 cours de la Liberation33405 Talence cedexFrance Division of Applied Mathematics Brown UniversityProvidenceRI 02912USA

In this paper,we reformulate the piecewise linear discontinuous Galerkin(DG)method for solving two dimensional steady state scalar conservation laws in the framework of residual distribution(RD)*** allows us to propose a new class of nonlinear stabilization that does not destroy the formal accuracy of the *** results are shown to demonstrate the behavior of this approach.

关键词： Discontinuous Galerkin schemes residual distribution schemes high order unstructured meshes

Gut microbiome:New perspectives for type 2 diabetes prevention and treatment

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World Journal of Clinical Cases 2023年第31期11卷 7508-7520页

作者： shu-Xiao Li Yan Guo School of Clinical Medicine Changchun University of Traditional Chinese MedicineChangchun 130000Jilin ProvinceChina

Type 2 diabetes mellitus(T2DM),which is distinguished by increased glucose levels in the bloodstream,is a metabolic disease with a rapidly increasing incidence ***,the etiology and characteristics of the mechanism of T2DM remain ***,abundant evidence has indicated that the intestinal microbiota is crucially involved in the initiation and progression of *** gut microbiome,the largest microecosystem,engages in material and energy metabolism in the human *** this review,we concentrated on the correlation between the gut flora and ***,we summarized the pathogenesis involving the intestinal flora in T2DM,as well as therapeutic approaches aimed at modulating the gut microbiota for the management of *** the analysis presented here,we draw attention to further exploration of these research directions.

关键词： Microbial metabolites Intestinal flora Probiotics Insulin resistance Type 2 diabetes

不同辣椒品种对细菌性斑点病抗病性鉴定与分析

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辽宁农业科学 2024年第4期 78-80页

作者：李柏宏刘丽于舒怡关天舒邹春蕾王辉辽宁省农业科学院植物保护研究所辽宁沈阳110161 辽宁省农业科学院蔬菜研究所辽宁沈阳110161

近年辽宁大型育苗企业辣椒细菌性斑点病发生严重,为有效利用辣椒抗病优质品种,试验采用人工接种的方法在辣椒8片真叶期对30份辽宁主栽辣椒品种进行室内抗病性鉴定工作。研究结果表明:神禾8819与韩国红峰平均病指13.92与14.42,为抗病品种... 详细信息

近年辽宁大型育苗企业辣椒细菌性斑点病发生严重,为有效利用辣椒抗病优质品种,试验采用人工接种的方法在辣椒8片真叶期对30份辽宁主栽辣椒品种进行室内抗病性鉴定工作。研究结果表明:神禾8819与韩国红峰平均病指13.92与14.42,为抗病品种(R);万金早椒与新品线椒玉平均病指17.17与15.25,为中抗品种(MR),4个品种均为线椒。其余3个甜椒、3个羊角椒、9个牛角椒、4个麻辣椒,7个螺丝椒平均病指在30.1~40.0,均为感病品种(S)。研究结果可为我省辣椒生产优选抗病品种与品种推广提供依据。

关键词：辣椒细菌性斑点病抗病性鉴定

GLOBAL WEAK SOLUTIONS TO THE α-MODEL REGULARIZATION FOR 3D COMPRESSIBLE EULER-POISSON EQUATIONS

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Acta Mathematica Scientia 2021年第3期41卷 679-702页

作者： Yabo REN Boling GUO shu WANG Faculty of Science Beijing University of TechnologyBeijing 100124China Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088China

Global in time weak solutions to the α-model regularization for the three dimensional Euler-Poisson equations are considered in this paper. We prove the existence of global weak solutions to α-model regularization for the three dimension compressible EulerPoisson equations by using the Fadeo-Galerkin method and the compactness arguments on the condition that the adiabatic constant satisfies γ >4/3.

关键词： Global weak solutions α-model regularization for Euler-Poisson equations Faedo-Galerkin method

Sol-gel combustion synthesis and characterization of CoCr2O4 ceramic powder used as color solar absorber pigment

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Optoelectronics Letters 2020年第5期16卷 365-368页

作者： LEI shu-lai LIANG Gui-jie WANG Yin ZHOU shu-xing ZHANG Xin LI shu-juan Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Institute of Mathematics Free University of BerlinBerlin 14195Germany

A facile citric acid assisted sol-gel combustion method was performed to synthesize cobalt chromite(CoCr2O4)ceramic *** effect of the annealing temperature on structure,morphologies,and optical properties of the prepared CoCr2O4 pigments were systematically studied by thermogravimetry,differential thermal analysis,X-ray diffraction(XRD)and field emission scanning electron microscope(FESEM).The results show that CoCr2O4 spinel crystal was achieved after heat treatment of the as-burnt powder at a relatively low temperature(400°C)and the average crystallite size of the CoCr2O4 pigment increased with the annealing ***,on the CIE parameters of CoCr2O4 pigment,a*and b*values became much more negative with the annealing temperature due to much more Co^2+ions located in tetrahedral sites and much more Cr^3+ions located in octahedral ***,the measured solar absorptance indicates that this ceramic pigment is expected to fabricate the color paint coating for solar absorber application.

关键词： coating ceramic powder

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高原城市拉萨典型VOCs排放源成分谱特征

环境科学 2024年第4期45卷 2011-2018页

作者：郭淑政叶春翔林伟立陈熠曾立民尹晴晴刘雪莉民族地区生态环境国家民委重点实验室(中央民族大学) 北京100081 北京大学环境科学与工程学院北京100871

高海拔地区低的气压和含氧量会影响燃烧和溶剂挥发过程,进而影响挥发性有机物(VOCs)的排放特征.然而,人们对海拔3 000 m以上的燃烧源或挥发源的VOCs排放特征的认识有限.拉萨市正在经历快速的经济发展和城市化进程,VOCs排放源日趋复杂.... 详细信息

高海拔地区低的气压和含氧量会影响燃烧和溶剂挥发过程,进而影响挥发性有机物(VOCs)的排放特征.然而,人们对海拔3 000 m以上的燃烧源或挥发源的VOCs排放特征的认识有限.拉萨市正在经历快速的经济发展和城市化进程,VOCs排放源日趋复杂.采集拉萨市机动车尾气、汽油挥发、柴油挥发、液化石油气和燃香等排放源VOCs样品进行分析,研究成分谱特征,并与平原地区的相比较.发现液化石油气VOCs排放谱以丙烷和丁烷为主,与平原地区的一致;汽油挥发中1,2,4-三甲苯占比最高,而汽油车尾气中异戊烷、正丁烷和丙烷占比高,1,2,4-三甲苯占比较低,这不同于平原地区的结果;柴油挥发比汽油及汽油车排放具有更高占比的C7以上高碳化合物;柴油车排放中含氧挥发性有机物(OVOC)占比最高,而平原地区则是丙烯和C7以上烷烃占比高;燃香排放中OVOC占比最高,特征示踪物是乙腈,且有不容忽视的异戊二烯排放.从甲苯与苯的比值上看,汽油车及柴油车排放与平原地区的结果基本一致,但两地区柴油挥发和燃香排放则不同.从苯、甲苯和乙苯比例三元图上看,柴油挥发落在工业及溶剂排放区内,有别于平原地区的结果 .与其它城市一样,烯烃和芳香烃化合物也是高原城市中具有高反应活性VOCs组分,二者分别对臭氧和二次有机气溶胶的生成有重要的贡献.初步研究结果表明,高原城市地区不同VOCs源的组分特征与平原地区有所差异,需要进一步深入研究,以应对潜在的环境和健康风险.

关键词：挥发性有机物(VOCs) 源谱成分谱排放特征羟基消耗速率(L_(·OH)) 臭氧生成潜势(OFP)

Adaptive command filter constraint control of rolling mill torsional vibration under current harmonic

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Journal of Iron and Steel Research International 2023年第9期30卷 1782-1791页

作者： shu-zong Chen Cheng Jia Chang-chun Hua Jia-qiang Chen Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina

An adaptive command filter control strategy was proposed to realize the asymptotic tracking of the roll speed,which successfully suppressed torsional vibration for the main drive system of the rolling mill with nonlinear friction,nonlinear damping,current harmonic,time-varying stiffness and unknown disturbance.A finite time predetermined performance method was proposed,so that the speed tracking error of the main transmission system was always constrained in the performance function and converged to its minimum boundary within the specified *** on the adaptive estimation of harmonic amplitude,the torque control law of the motor was obtained by using the filter backstepping method,which prevented the torsional vibration of the system caused by the input fluctuation and avoided the complexity explosion of the controller design,and the stability of the closed-loop system was strictly proved by the Lyapunov *** actual numerical simulation verified the effectiveness of the proposed control strategy.

关键词： Main drive system Torsional vibration Command filter Finite time predetermined performance

A Machine Learning Framework with Feature Selection for Floorplan Acceleration in IC Physical Design

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Journal of Computer Science & Technology 2020年第2期35卷 468-474页

作者： shu-Zheng Zhang Zhen-Yu Zhao Chao-Chao Feng Lei Wang College of Computer Science and Technology National University of Defense TechnologyChangsha 410003China

Floorplan is an important process whose quality determines the timing closure in integrated circuit(IC)physical *** generating a floorplan with satisfying timing result is time-consuming because much time is spent on the generation-evaluation *** machine learning to the floorplan stage is a potential method to accelerate the floorplan ***,there exist two challenges which are selecting proper features and achieving a satisfying model *** this paper,we propose a machine learning framework for floorplan acceleration with feature selection and model stacking to cope with the challenges,targeting to reduce time and effort in integrated circuit physical ***,the proposed framework supports predicting post-route slack of static random-access memory(SRAM)in the early floorplan ***,we introduce a feature selection method to rank and select important *** both feature importance and model accuracy,we reduce the number of features from 27 to 15(44%reduction),which can simplify the dataset and help educate novice ***,we build a stacking model by combining different kinds of models to improve *** 28 nm technology,we achieve the mean absolute error of slacks less than 23.03 ps and effectively accelerate the floorplan process by reducing evaluation time from 8 hours to less than 60 *** on our proposed framework,we can do design space exploration for thousands of locations of SRAM instances in few seconds,much more quickly than the traditional *** practical application,we improve the slacks of SRAMs more than 75.5 ps(177%improvement)on average than the initial design.

关键词： physical design machine learning feature selection design space exploration

能谱CT与超声造影评价肝癌DEB-TACE疗效的对比研究

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中国CT和MRI杂志 2024年第9期22卷 94-96页

作者：袁慧锋叶书文李臻郑州大学第一附属医院放射介入科河南郑州450052

目的对比分析能谱CT与超声造影在评价肝癌DEB-TACE术后疗效评估的应用价值。方法前瞻性纳入在郑州大学第一附属医院放射介入科接受DEB-TACE治疗的38例肝细胞癌患者,所有患者均于DEB-TACE术后4~6周接受CT能谱扫描和声学造影用评价以疗效... 详细信息

目的对比分析能谱CT与超声造影在评价肝癌DEB-TACE术后疗效评估的应用价值。方法前瞻性纳入在郑州大学第一附属医院放射介入科接受DEB-TACE治疗的38例肝细胞癌患者,所有患者均于DEB-TACE术后4~6周接受CT能谱扫描和声学造影用评价以疗效,检查后一周内接受DSA检查。将DSA检查结果作为“金标准”,分析能谱CT与超声造影评估肝细胞癌DEB-TACE疗效的差异。应用SPSS23.0统计分析相关数据,计算两种方法的灵敏度、特异度、漏诊率、误诊率、约登指数,MedCalc绘制ROC曲线,通过对比AUC来比较两种检查方法的检验效能。结果能谱CT诊断残癌或复发的结果:灵敏度为93.33%,特异度为100.0%,误诊率为0.0%,漏诊率为6.67%,正确率94.74%,约登指数93.33%。超声造影诊断残癌或复发的结果:灵敏度76.67%,特异度100.00%,误诊率0%,漏诊率23.33%,正确率81.58%,约登指数76.67%。能谱CT和声学造影的曲线下面积分别为0.967、0.883,统计学差异显著(P<0.05)。结论对比声学造影,能谱CT对评估肝细胞癌DEB-TACE疗效评价的准确性更高,在肝细胞DEB-TACE术后患者疗效评估中有重要价值。

关键词：肝癌能谱CT 超声造影灵敏度特异度经导管肝动脉化疗栓塞术