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Convergence ofADistributional Monte Carlo Method for the Boltzmann Equation

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Advances in Applied Mathematics and Mechanics 2012年第1期4卷 102-121页

作者： Christopher R.Schrock aihua W.wood Department of Mathematics and Statistics Air Force Institute of TechnologyWright-Patterson AFBOH 45433USA

Direct Simulation Monte Carlo(DSMC)methods for the Boltzmann equation employ a point measure approximation to the distribution function,as simulated particles may possess only a single *** representation limits the method to converge only weakly to the solution of the Boltzmann *** kernel density estimation we have developed a stochastic Boltzmann solver which possesses strong convergence for bounded and L∞solutions of the Boltzmann *** is facilitated by distributing the velocity of each simulated particle instead of using the point measure approximation inherent to *** propose that the development of a distributional method which incorporates distributed velocities in collision selection and modeling should improve convergence and potentially result in a substantial reduction of the variance in comparison to DSMC *** this end,we also report initial findings of modeling collisions distributionally using the Bhatnagar-Gross-Krook collision operator.

关键词： Direct simulation monte carlo rarefied gas dynamics Boltzmann equation convergence proof

A Modified Helmholtz Equation with Impedance Boundary Conditions

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Advances in Applied Mathematics and Mechanics 2012年第6期4卷 703-718页

作者： Robert S.Callihan aihua W.wood Air Force Institute of Technology 2950 Hobson WayWright-Patterson AFBOH 45433USA

Here considered is the problem of transient electromagnetic scattering from overfilled cavities embedded in an impedance ground *** artificial boundary condition is introduced on a semicircle enclosing the cavity that couples the fields from the infinite exterior domain to those fields inside.A Green’s function solution is obtained for the exterior domain,while the interior problem is solved using finite element ***-posedness of the associated variational formulation is achieved and convergence and stability of the numerical scheme *** experiments show the accuracy and robustness of the method.

关键词： Helmholtz equation impedance boundary conditions finite element method

A Hybrid Finite Element-Laplace Transform Method for the Analysis of Transient Electromagnetic Scattering by an Over-Filled Cavity in the Ground Plane

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Communications in Computational Physics 2009年第1期5卷 126-141页

作者： Junqi Huang aihua W.wood Michael J.Havrilla Air Force Institute of Technology 2950 Hobson WayWright-Patterson AFBOH 45433USA

A hybrid finite element-Laplace transform method is implemented to analyze the time domain electromagnetic scattering induced by a 2-D overfilled cavity embedded in the infinite ground *** algorithm divides the whole scattering domain into two,interior and exterior,*** the interior sub-domain which covers the cavity,the problem is solved via the finite element *** problem is solved analytically in the exterior sub-domain which slightly overlaps the interior subdomain and extends to the rest of the upper half *** use of the Laplace transform leads to an analytical link condition between the overlapping *** analytical link guides the selection of the overlapping zone and eliminates the need to use the conventional Schwartz *** dramatically improves the efficiency for solving transient scattering *** solutions are tested favorably against analytical ones for a canonical *** perfect link over the artificial boundary between the finite element approximation in the interior and analytical solution in the exterior further indicates the reliability of the *** error analysis is also performed.

关键词： Overfilled cavity time domain electromagnetic scattering Laplace transform finite element method

Valorization of Camellia oleifera oil processing byproducts to value-added chemicals and biobased materials: A critical review

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Green Energy & Environment 2024年第1期9卷 28-53页

作者： Xudong Liu Yiying Wu Yang Gao Zhicheng Jiang Zicheng Zhao Wenquan Zeng Mingyu Xie Sisi Liu Rukuan Liu Yan Chao Suli Nie aihua Zhang Changzhu Li Zhihong Xiao State Key Laboratory of Utilization of woody Oil Resource Hunan Academy of ForestryChangsha410004China Key Laboratory of State Forestry and Grassland Administration on Utilization Science for Southern woody Oil Resource Hunan Academy of ForestryChangsha410004China Hunan Provincial Key Laboratory of Oils and Fats Molecular Structure and Function Changsha410004China State Key Laboratory of Separation Membranes and Membrane Processes College of ChemistryTiangong UniversityTianjin300387China College of Biomass Science and Engineering Sichuan UniversityChengdu610065China College of Mechanical Engineering and Mechanics Xiangtan UniversityXiangtan411105China

The *** oil processing industry generates large amounts of solid wastes,including *** shell(COS)and *** cake(COC).Distinct from generally acknowledged lignocellulosic biomass(corn stover,bamboo,birch,etc.),Camellia wastes contain diverse bioactive substances in addition to the abundant lignocellulosic components,and thus,the bioreﬁnery utilization of *** processing byproducts involves complicated processing *** reviewﬁrst summarizes various technologies for extracting and converting the main components in *** oil processing byproducts into value-added chemicals and biobased materials,as well as their potential ***,ultrasound,and Soxhlet extractions are compared for the extraction of functional bioactive components(tannin,ﬂavonoid,saponin,etc.),while solvothermal conversion and pyrolysis are discussed for the conversion of lignocellulosic components into value-added *** application areas of these chemicals according to their properties are introduced in detail,including utilizing antioxidant and anti-in-ﬂammatory properties of the bioactive substances for the speciﬁc application,as well as drop-in chemicals for the substitution of unrenewable fossil fuel-derived *** addition to chemical production,biochar fabricated from COS and its applications in theﬁelds of adsorption,supercapacitor,soil remediation and wood composites are comprehensively reviewed and ***,based on the compositions and structural characteristics of *** byproducts,the development of full-component valorization strategies and the expansion of the appli-cationﬁelds are proposed.

关键词： Camellia oleifera shell Camellia oleifera cake Value-added chemicals Bioactive components Biobased materials

核桃壳木醋液植物生长促进剂响应面法配方优化

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中国南方果树 2024年第3期53卷 263-269页

作者：肖坤孙慧敏阎爱华围场县林业和草原局河北承德068450 河北农业大学林学院/河北省林木种质资源与森林保护重点实验室河北保定071000

为优化以核桃壳木醋液为主的植物生长促进剂配方,在单因素试验的基础上,以核桃的叶面积为响应值,采用响应面法检测不同混合物比例对核桃的促生效果。结果表明,在木醋液体积分数0.5%(200倍液)、KH 2 PO 4质量浓度0.2%、过磷酸钙质量浓度1... 详细信息

为优化以核桃壳木醋液为主的植物生长促进剂配方,在单因素试验的基础上,以核桃的叶面积为响应值,采用响应面法检测不同混合物比例对核桃的促生效果。结果表明,在木醋液体积分数0.5%(200倍液)、KH 2 PO 4质量浓度0.2%、过磷酸钙质量浓度1%、硼酸质量浓度0.2%、尿素质量浓度0.3%时,1年生核桃叶面积最大,达到82.77 cm^(2),与预测值(85.23 cm^(2))无显著差异,表明促生条件最佳。在回归方程中核桃壳木醋液对叶面积的影响最显著,可用于进一步制备核桃壳木醋液生长促进剂。

关键词：核桃壳木醋液响应面法促生效果

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中医药特色化干预对不同证候阈下抑郁患者的疗效及安全性比较

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现代中医临床 2024年第3期31卷 15-20页

作者：鱼童朱爱华林欣潮杨承芝方婷北京中医药大学东直门医院北京100010 中国中医科学院广安门医院

目的采用郁乐饮+团体心理治疗(情景化沙龙)+五行角调音乐方式对阈下抑郁患者进行干预,探讨中医药特色化干预对不同证候阈下抑郁患者的疗效。方法将76例阈下抑郁患者随机分为试验组56例和对照组20例。试验组采用团体心理治疗(情景化沙... 详细信息

目的采用郁乐饮+团体心理治疗(情景化沙龙)+五行角调音乐方式对阈下抑郁患者进行干预,探讨中医药特色化干预对不同证候阈下抑郁患者的疗效。方法将76例阈下抑郁患者随机分为试验组56例和对照组20例。试验组采用团体心理治疗(情景化沙龙)+郁乐饮+五行角调音乐的方式进行干预;对照组仅采用团体心理治疗(情景化沙龙)的方式进行干预。疗程12周,分别于干预前、干预12周时测量CES-D、HAMD-17、中医证候量表和安全性指标。结果 2组患者在干预12周后CES-D量表评分、HAMD-17量表评分较干预前均减少(P<0.05);肝郁脾虚证患者治疗后HAMD-17量表评分减少,差异具有统计学意义(P<0.05)。结论郁乐饮+团体心理治疗+五行角调音乐可以有效改善肝郁脾虚证阈下抑郁患者抑郁状态,同时减轻其躯体症状。

关键词：阈下抑郁郁乐饮五行角调音乐团体心理治疗

Using nonparametric modeling approaches and remote sensing imagery to estimate ecological welfare forest biomass

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Journal of Forestry Research 2018年第1期29卷 151-161页

作者： Chaofan Wu Hongxiang Tao Manyu Zhai Yi Lin Ke Wang Jinsong Deng aihua Shen Muye Gan Jun Li Hong Yang College of Environmental and Resource Sciences Zhejiang University Hangzhou 310058 China Zhejiang Forestry Academy Hangzhou 310023 China School of Civil Engineering and Environmental Sciences and School of Meteorology University of Oklahoma Norman OK 73019 USA State Key Laboratory of Hydro Science and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 China

The spatial distribution of forest biomass is closely related with carbon cycle, climate change, forest productivity, and biodiversity. Efficient quantification of biomass provides important information about forest quality and health. With the rising awareness of sustainable development, the ecological benefits of forest biomass attract more attention compared to traditional wood supply function. In this study, two nonparametric modeling approaches, random forest（RF） and support vector machine were adopted to estimate above ground biomass（AGB） using widely used Landsat imagery in the region,especially within the ecological forest of Fuyang District in Zhejiang Province, China. Correlation analysis was accomplished and model parameters were optimized during the modeling process. As a result, the best performance modeling method RF was implemented to produce an AGB estimation map. The predicted map of AGB in the study area showed obvious spatial variability and demonstrated that within the current ecological forest zone, as well as the protected areas, the average of AGB were higher than the ordinary forest. The quantification of AGB was proven to have a close relationship with the local forest policy and management pattern, which indicated that combining remote-sensing imagery and forest biophysical property would provide considerable guidance for making beneficial decisions.

关键词： Above ground biomass Ecological forest Forest management Landsat Random forest

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基于FTIR的针阔叶材木质素和纤维素特性

东北林业大学学报 2009年第9期37卷 79-81,90页

作者：胡爱华邢世岩巩其亮山东农业大学泰安271018

采用红外光谱技术研究了银杏、雪松、毛白杨等30种针阔叶材的红外光谱,对表征其纤维素和木质素的特征吸收峰进行了研究,结果表明:①针叶材在1740cm-1处吸收峰峰值普遍低于阔叶材,1510cm-1处针叶材吸收峰峰值较阔叶材大,说明针阔叶树木... 详细信息

采用红外光谱技术研究了银杏、雪松、毛白杨等30种针阔叶材的红外光谱,对表征其纤维素和木质素的特征吸收峰进行了研究,结果表明:①针叶材在1740cm-1处吸收峰峰值普遍低于阔叶材,1510cm-1处针叶材吸收峰峰值较阔叶材大,说明针阔叶树木材木质素和纤维素相对含量差异明显;②针叶材的1595/1505cm-1值小于阔叶材,1270/1230cm-1值大于阔叶材,说明针阔叶树种间木质素的组成不同;③银杏的红外光谱特征总体与针叶材一致,但1595/1505cm-1和1270/1230cm-1吸收峰吸收强度比值均接近阔叶材,表明银杏在木质素组成上有向阔叶树进化的趋势。

关键词：红外光谱针叶材阔叶材木质素纤维素

Genomic insights into the uncultured genus‘Candidatus Magnetobacterium' in the phylum Nitrospirae

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Genomic insights into the uncultured genus‘Candidatus Magne...