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结合三维边缘特征约束的网格模型优化方法

地球信息科学学报 2024年第5期26卷 1138-1150页

作者：张昊王竞雪谢潇辽宁工程技术大学测绘与地理科学学院阜新123000 中国科学院沈阳应用生态研究所辽宁省环境计算与可持续发展重点实验室沈阳110116

对于具有复杂几何结构特征的建筑物,三维网格模型重建结果易存在表面扭曲、边缘特征平滑的问题,无法较好地反映重建目标的真实信息。针对上述问题,本文提出一种结合三维边缘约束的网格模型优化方法。该方法以OpenMVS算法得到的初始网格... 详细信息

对于具有复杂几何结构特征的建筑物,三维网格模型重建结果易存在表面扭曲、边缘特征平滑的问题,无法较好地反映重建目标的真实信息。针对上述问题,本文提出一种结合三维边缘约束的网格模型优化方法。该方法以OpenMVS算法得到的初始网格为基础数据,利用变分原理构建能量函数,将网格模型优化问题转换为能量函数最小化问题。首先,从多视图像中提取三维边缘点,以三维边缘点构成的边缘轮廓来定位网格模型边缘区域;接着,利用灰度一致性测度构建数据项,利用顶点自身曲率构建平滑项,利用三维边缘轮廓约束构建附加约束项,将3个约束项构建为一个总体能量函数;最后,采用梯度下降法迭代求解总体能量函数最小值,将梯度变化量分配到网格模型的顶点上来驱动网格形变,以此优化模型。选取Strecha数据集中两个真实室外场景和ETH3D数据集中一个真实室内场景进行优化实验,使用ETH3D评估框架对实验结果进行评估。结果表明,经本文算法优化后的网格模型完整度和精度最高为89.76%、94.45%,本文算法在解决复杂几何结构建筑物模型边缘优化问题的基础上,提高了建筑物模型的准确程度。

关键词：网格模型优化灰度一致性正则化边缘约束能量函数变分法梯度下降法迭代求解

基于多视立体视觉与Leiden图聚类的多视图直线匹配

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地球信息科学学报 2024年第7期26卷 1629-1645页

作者：兰泽清王竞雪王丽芹辽宁工程技术大学测绘与地理科学学院阜新123000 辽宁工程技术大学地理空间信息服务协同创新研究院阜新123000 辽阳市国土资源勘查规划院辽阳111000

直线特征的精确匹配对三维模型的重建与优化具有重要意义。但是传统的双视图直线匹配由于视图数量较少导致直线匹配结果鲁棒性较差,且对于存在断裂的直线提取结果,同一直线在不同影像上提取直线的数目不等,导致直线匹配结果完整性较差... 详细信息

直线特征的精确匹配对三维模型的重建与优化具有重要意义。但是传统的双视图直线匹配由于视图数量较少导致直线匹配结果鲁棒性较差,且对于存在断裂的直线提取结果,同一直线在不同影像上提取直线的数目不等,导致直线匹配结果完整性较差。针对上述问题,本文提出多视图立体视觉(Multiple View Stereo,MVS)与Leiden图聚类相结合的多视图直线匹配算法。该算法首先使用直线提取算法和MVS三维重建算法对输入的多视影像分别进行直线信息提取和多视图三维信息提取,得到各视图上的直线与覆盖多视图场景的稠密三维点及其相关信息,并以此构建直线描述符;接着通过三维直线投影角度约束、点-线位置关系约束及同名点约束对匹配候选进行筛选,并根据各视图上直线间的相似性关系以各视图上的直线为节点,直线间的相似性得分为边权重构建无向图,同时剔除无向图中由单个节点构成的连通分量,得到连通分量集合,即初始匹配结果;最后对各个连通分量的节点基于同视图共线约束进行重构,得到子无向图,并对子无向图节点使用Leiden算法进行聚类。最终在多视影像上得到精确的直线匹配结果。本文选取大疆无人机拍摄的2组影像以及网上公开的1组影像进行实验。实验结果表明,采用本文算法获得的直线匹配结果较对比算法在直线匹配数目以及匹配正确率上均有所提升。

关键词：多视图直线匹配特征匹配几何约束无向图稠密三维点多视图立体视觉 Leiden算法

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基于SVM混合核的不透水面提取及扩张分析

测绘通报 2024年第3期 43-48页

作者：冀建任王竞雪王丽芹辽宁工程技术大学测绘与地理科学学院辽宁阜新123000 辽宁工程技术大学地理空间信息服务协同创新研究院辽宁阜新123000 辽阳市国土资源勘查规划院辽宁辽阳111000

利用支持向量机中单一核函数提取不透水面时存在时间复杂度高和提取精度低的问题。针对该问题,本文在径向基核函数的基础上引入多项式核函数,提出了一种混合核函数的不透水面提取方法。首先,由于属性不同的地物具有相似的光谱信息,在特... 详细信息

利用支持向量机中单一核函数提取不透水面时存在时间复杂度高和提取精度低的问题。针对该问题,本文在径向基核函数的基础上引入多项式核函数,提出了一种混合核函数的不透水面提取方法。首先,由于属性不同的地物具有相似的光谱信息,在特征提取过程中将光谱信息与图像熵纹理信息相结合,可更加清楚地区分各地物类别。然后,在径向基核函数的基础上引入多项式核,可分别从局部和全局角度获取影像的特征信息,提高不透水面提取精度。最后,在不透水面提取结果基础上进行时空演变分析。本文利用阜新市主城区2009—2021年Landsat影像进行试验。结果表明,光谱与熵纹理相结合方法可改善特征提取效果,提升不透水面提取精度。与单一核函数提取方法对比,利用本文方法提取不透水面精度提高了2.5%,证明了该方法的有效性。

关键词：不透水面纹理特征支持向量机混合核函数时空分析

Microenvironment Modulation in Metal−Organic Framework-Based Catalysis

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Accounts of Materials Research 2021年第5期2卷 327-339页

作者： Long Jiao jingxue wang Hai-Long Jiang Hefei National Laboratory for Physical Sciences at the Microscale CAS Key Laboratory of Soft Matter ChemistryDepartment of ChemistryUniversity of Science and Technology of ChinaHefeiAnhui 230026P.R.China

CONSPECTUS:The fine design and regulation of catalysts play critical roles in the development of catalysis.The microenvironment,which gives rise to unique spatial structures and electronic properties around catalytic sites,has been proven to dramatically regulate catalytic behavior in enzymes and homogeneous catalysis.However,understanding the microenvironment modulation(MEM)of catalytic sites remains challenging and very limited in heterogeneous catalysis mainly due to the lack of structural precision and/or tailorability of traditional solid catalysts.Among diverse materials,metal−organic frameworks(MOFs),a class of porous crystalline solids,have been intensively studied as heterogeneous catalysts in recent years.The atomically precise and well tunable structures of MOFs make them an ideal platform for rationally regulating the microenvironment surrounding catalytic sites.Accordingly,their well-defined structures hold great promise for elucidating how the microenvironment modulation affects the resulting catalytic performance.Nevertheless,the investigations of accurate control over the microenvironment of catalytic sites in MOFs for modulated catalysis are still very limited.Therefore,it is of great importance to summarize the related results and provide in-depth insights into microenvironment modulation in MOF-based catalysis,accelerating the future development of this emerging research topic.In this Account,we have presented a summary of our recent attempts to optimize the catalytic performance of MOF-based materials via microenvironment modulation.In view of the unique component and structural advantages of MOFs,we deliver the general fundamentals for rational control over the microenvironment in MOF-based catalysis.Initially,the great opportunities brought about by MOFs for accurate control over microenvironment engineering,including the origin of abundant active sites,flexible regulation strategies,and well-defined structure,are introduced in detail.In the next section,we focus on the specific strategies o

关键词： catalysis rational precise

Necrotic enteritis challenge regulates peroxisome proliferator-1 activated receptors signaling and β-oxidation pathways in broiler chickens

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Animal Nutrition 2021年第1期7卷 239-251页

作者： Kosar Gharib-Naseri Sara de Las Heras-Saldana Sarbast Kheravii Lihong Qin jingxue wang Shu-Biao Wu School of Environment and Rural Science University of New EnglandArmidaleNSW2351Australia Animal Science and Husbandary Branch Jilin Academy of Agricultural SciencesGongzhulingJilin136100China College of Life Sciences Shanxi UniversityTaiyuanShanxi030006China

Necrotic enteritis(NE)is an important enteric disease in poultry and has become a major concern in poultry production in the post-antibiotic era.The infection with NE can damage the intestinal mucosa of the birds leading to impaired health and,thus,productivity.To gain a better understanding of how NE impacts the gut function of infected broilers,global mRNA sequencing(RNA-seq)was performed in the jejunum tissue of NE challenged and non-challenged broilers to identify the pathways and genes affected by this disease.Briefly,to induce NE,birds in the challenge group were inoculated with 1 mL of Eimeria species on day 9 followed by 1 mL of approximately 108 CFU/mL of a NetB producing Clostridium per-fringens on days 14 and 15.On day 16,2 birds in each treatment were randomly selected and euthanized and the whole intestinal tract was evaluated for lesion scores.Duodenum tissue samples from one of the euthanized birds of each replicate(n=4)was used for histology,and the jejunum tissue for RNA extraction.RNA-seq analysis was performed with an Illumina RNA HiSeq 2000 sequencer.The differ-entially expressed genes(DEG)were identified and functional analysis was performed in DAVID to find protein-protein interactions(PPI).At a false discovery rate threshold<0.05,a total of 377 DEG(207 upregulated and 170 downregulated)DEG were identified.Pathway enrichment analysis revealed that DEG were considerably enriched in peroxisome proliferator-activated receptors(PPAR)signaling(P<0.01)andβ-oxidation pathways(P<0.05).The DEG were mostly related to fatty acid metabolism and degradation(cluster of differentiation 36[CD36],acyl-CoA synthetase bubblegum family member-1[ACSBG1],fatty acid-binding protein-1 and-2[FABP1]and[FABP2];and acyl-coenzyme A synthetase-1[ACSL1]),bile acid production and transportation(acyl-CoA oxidase-2[ACOX2],apical sodium-bile acid transporter[ASBT])and essential genes in the immune system(interferon-,[IFN-γ],LCK proto-oncogene,Src family tyrosine kinase[LCK],zeta chain of T cell receptor associated protein kin

关键词： Necrotic enteritis Clostridium perfringens Transcriptome Fatty acid metabolism Broiler Challenge

乌兰布和荒漠绿洲过渡带白刺灌丛沙堆防风效应风洞模拟

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农业工程学报 2024年第3期40卷 147-155页

作者：智丹王京学肖辉杰辛智鸣李俊然北京林业大学水土保持学院北京100083 中国林业科学研究院沙漠林业实验中心磴口015200 香港大学地理系中国香港999077

灌丛沙堆作为荒漠绿洲过渡带广泛存在的生物地貌类型,其在不同演化阶段和植被盖度下的风速分布及防风效应对土壤风蚀灾害控制具有重要意义。为揭示灌丛沙堆演化阶段及植被盖度对周围风场结构特征及防风效应指标的影响规律,该研究以乌兰... 详细信息

灌丛沙堆作为荒漠绿洲过渡带广泛存在的生物地貌类型,其在不同演化阶段和植被盖度下的风速分布及防风效应对土壤风蚀灾害控制具有重要意义。为揭示灌丛沙堆演化阶段及植被盖度对周围风场结构特征及防风效应指标的影响规律,该研究以乌兰布和沙漠荒漠绿洲过渡带单个和两个白刺(Nitraria tangutorum)灌丛沙堆为对象,利用风洞模拟试验测定其在4个不同演化阶段(雏形阶段、发育阶段、稳定阶段、活化阶段)和3种不同植被盖度(0、40%及70%)工况下竖直和水平面的风速分布,探讨演化阶段及植被盖度对相对速率、防风效能等防风效应指标的影响。研究发现,不同演化阶段的白刺灌丛沙堆在0~0.8H(H为灌丛沙堆高度)高度范围内、距沙堆中心-H~5H水平范围内风速有显著变化;对比坡前减速区、上方加速区、两侧急流区和后方减速区的风速变化发现,白刺灌丛沙堆在后方减速区的风速变化最为显著,处于稳定阶段的灌丛沙堆在植被盖度为70%时的风速最大可减少90%;不同演化阶段中,稳定阶段灌丛沙堆对风速的削减更为显著,防风效能较大,而处于雏形阶段的灌丛沙堆的防风能力相对较弱;在两个平行于风向排列的灌丛沙堆的相互影响下,沙堆之间丘间低地的防风效能比单个灌丛沙堆有所提高,且第二个灌丛沙堆下游区域的防风效能略小于两个灌丛沙堆间的丘间低地;各演化阶段单个和两个灌丛沙堆周围的防风效能均随植被盖度增大而增大。该研究结果可为乌兰布和荒漠绿洲过渡带土壤风蚀防治提供参考。

关键词：风洞植被风速分布防风效能乌兰布和沙漠荒漠绿洲过渡带白刺灌丛沙堆

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乌兰布和荒漠绿洲风沙特性及防护林防护效应

中国水土保持科学 2024年第3期22卷 136-145页

作者：蔡俊顺王京学肖辉杰辛智鸣王百田李俊然北京林业大学水土保持学院北京100083 内蒙古磴口荒漠生态生态系统国家定位观测研究站内蒙古磴口015200 香港大学地理系中国香港999077

农田防护林在保持水土及土壤风蚀防控方面发挥着重要作用。为了探究真实大气环境下绿洲防护林体系的防风阻沙效益,以乌兰布和荒漠绿洲防护林为研究对象,利用位于荒漠绿洲过渡带和绿洲的近地面沙尘观测塔监测的2019—2020年不同高度处的... 详细信息

农田防护林在保持水土及土壤风蚀防控方面发挥着重要作用。为了探究真实大气环境下绿洲防护林体系的防风阻沙效益,以乌兰布和荒漠绿洲防护林为研究对象,利用位于荒漠绿洲过渡带和绿洲的近地面沙尘观测塔监测的2019—2020年不同高度处的风速、风向和沙尘数据,分析荒漠绿洲过渡带和绿洲的风沙分布统计特性。结果表明:荒漠绿洲过渡带和绿洲主导风向为东北和西南方向,2区域内平均风速均随观测高度增加逐渐增大;从荒漠绿洲过渡带至绿洲,受防护林体系的影响,平均风速整体减弱,≥4~8 m/s的中风速和≥8 m/s的高风速样本比例平均减少约8.8%和7.8%;荒漠绿洲过渡带和绿洲月最大平均风速多出现在夏秋2季以及春季末,且月最大平均风速与平均风速均值呈线性关系;2区域沙通量随着高度的增加逐渐减少,受防护林带影响同观测高度水平沙通量和垂直沙通量分别减少65%和36%;输沙方向整体朝东和东南偏东方向,该方向在绿洲受观测高度影响较小,在荒漠绿洲过渡带不同高度输沙方向会产生差异,输沙势从荒漠绿洲过渡带至绿洲总体降低。防护林体系对区域范围内的风沙活动影响明显,能够减轻风蚀所带来的水土流失,对绿洲可持续发展具有重要价值。

关键词：防护林风沙运动统计特性防风阻沙乌兰布和荒漠绿洲

Cloning and Expression Analysis of THWRKY12 Gene from Tamarix hispida

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Agricultural Biotechnology 2013年第5期2卷 55-57页

作者： jingxue wang Yuekun TANG Qi LIU Chunqiang LIANG Yucheng wang State Key Laboratory of Forest Genetics and Tree Breeding Northeast Forestry University

[ Objective] This study aimed to clone and analyze the expression of THWRKY12 gene in Tamarix hispida. [Method] T. hispida seedlings were treated with 400 mmol/L NaC1 solutlon, 20% PEG and 100 μmol/L ABA, respectively. The expression of THIVRKY12 gene in different tissues was investigated by RT-PCR technology. [Result] Under treatments of NaC1 and PEG, the expression of THWRKY12 gene in different tissues of T. h/sp/da seedlings showed an overall upregulated trend, suggesting that THWRKYI2 is related with the saline-alkali resistance and drought resistance of T. hispida. Under ABA treatment, THWRKY12 gene had approximately the same expression pattern with the former two, indicating that THWRKY12 gene may involve in the regulation and control of the saline-al- kali resistance and drought resistance of T. hispida through the signal pathway regulated by ABA. [ Conclusion] This study laid foundation for investigating the functions of WRKY gene in the stress resistance of T. hispida.

关键词： Tamarix hispida WRKY transcription factor RT-PCR Saline-alkali stress Drought stress

Preparation and properties of bacteriophage-borne enzyme degrading bacterial exopolysaccharide

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High Technology Letters 2008年第2期14卷 210-215页

作者：牟海津 wang jingxue Jiang Xiaolu Liu Zhihong Colege of Food Sciences and Engineering Ocean University of China Qingdao 266003 P.R.China＇ Yellow Sea Fisheries Research Institute Qingdao 265071 P. R. China

Bacteriophages infected different serotypes of Klebsiella were isolated from sewage.Among them,aheat-stable polysaccharide depolymerase enzyme which could degrade bacterial exopolysaccharide effec-tively was prepared from the phage infecting Klebsiella K13.Treatment at 60℃ for 30 min could inacti-vate most of the K13 phage,with the titration decreasing from 6.4×10~8 PFU/mL to 1.6×10~6 PFU/mL.However,no obvious loss of phage enzyme activity was found after this treatment.The optimum hydrolytictemperature of phage enzyme was 60℃,with an activity 57% higher than that at 30℃.The addition ofphage enzyme could result in a rapid decrease of viscosity of exopolysaccharide(EPS)solution withinminutes,indicating that K13 phage polysaccharide depolymerase acts as a kind of endo-glyeanohydrolase.HPLC and reducing sugar analysis showed that the hydrolysis of EPS approached approximately the maxi-mum at 4h when the final concentration of phage was 6.0×10~8 PFU/mL.The results showed that Kleb-sieUa K13 phage depolymerase enzyme could be used as a good tool for the preparation of EPS oligosac-charide.

关键词：克雷伯氏菌抗菌素多解聚酶水解温度