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Surface Reconstruction of 3D Scattered Data with Radial Basis Functions

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Communications in Mathematical Research 2010年第2期26卷 183-192页

作者： Du XIN-WEI YANG XIAO-YING liang xue-zhang School of Mathematics Jilin University Changchun 130012 College of Mathematics Changchun University of Technology Changchun 130021

We use Radial Basis Functions （RBFs） to reconstruct smooth surfaces from 3D scattered data. An object＇s surface is defined implicitly as the zero set of an RBF fitted to the given surface data. We propose improvements on the methods of surface reconstruction with radial basis functions. A sparse approximation set of scattered data is constructed by reducing the number of interpolating points on the surface. We present an adaptive method for finding the off-surface normal points. The order of the equation decreases greatly as the number of the off-surface constraints reduces gradually. Experimental results are provided to illustrate that the proposed method is robust and may draw beautiful graphics.

关键词： radial basis function scattered data implicit surface surface reconstruction

Radial growth in Qinghai spruce is most sensitive to severe drought in the Qilian Mountains of Northwest China

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Journal of Forestry Research 2024年第3期35卷 73-86页

作者： Xuge Wang liang Jiao Ruhong xue Peng zhang Dashi Du Mengyuan Wei Qian Li College of Geography and Environmental Science Northwest Normal UniversityNo.967Anning East RoadLanzhou 730070People's Republic of China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070Gansu ProvincePeople's Republicof China

Global warming and frequent extreme drought events lead to tree death and extensive forest decline,but the underlying mechanism is not *** drought years,cambial development is more sensitive to climate change,but in different phenological stages,the response rela-tionship is ***,the dynamic relationship between tree radial growth and climatic/environmental fac-tors needs to be *** thus continuously monitored radial growth of Qinghai spruce(Picea crassifolia Kom.)and environmental factors from January 2021 to November 2022 using point dendrometers and portable meteorological weather stations in the central area of the Qilian *** relationship and stability between the radial growth of Qinghai spruce and environmental factors were compared for different levels of drought in 2021 and *** year 2022 had higher temperatures and less precipitation and was drier than *** with 2021,the growing period in 2022 for Qinghai spruce was 10 days shorter,maximum growth rate(Grmax)was 4.5μm·d^(-1) slower,and the initiation of growth was 6 days *** of Qinghai spruce was always restricted by drought,and the stem radial increment(SRI)was more sensitive to precipitation and air relative *** changes in cumulative radial growth were divided into four phenological stages according to the time of growth onset,cessation,and maximum growth rate(Grmax)of Qinghai *** responses of SRI to climate change were stronger in Stage 3 and Stage 4 of 2021 and stronger in Stage 1(initiation growth stage)and Stage 3 of *** results provide important information on the growth of the trees in response to drought and for specific managing forests as the climate warms.

关键词： Picea crassifolia Radial growth dynamics Severe drought Response stability Point dendrometer

Cracking on a nickel-based superalloy fabricated by direct energy deposition

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China Foundry 2024年第4期21卷 311-318页

作者： xue zhang Ya-hang Mu liang Ma Jing-jing liang Yi-zhou Zhou Xiao-feng Sun Jin-guo Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Cracks have consistently been a significant challenge limiting the development of additive manufactured nickel-based *** is essential to investigate the location of cracks and their forming *** study extensively examines the impact of solidification process,microstructural evolution,and stress concentration on crack initiation during direct energy deposition(DED).The results emphasize that the crack formation is significantly related to large-angle grain boundaries,rapid cooling *** caused by large-angle grain boundaries and a fast-cooling rate predominantly appear near the edge of the deposited *** cracks are more likely to form near the top of the deposited sample,due to the presence ofγ/γ'*** secondary dendritic arm and the carbides in the interdendritic regions can obstruct liquid flow during the final stage of solidification,which results in the formation of solidification cracks and *** work paves the way to avoid cracks in nickel-based superalloys fabricated by DED,thereby enhancing the performance of superalloys.

关键词： location cracks direct energy deposition nickel-based superalloys

Elevation response of above-ground net primary productivity for Picea crassifolia to climate change in Qilian Mountains of Northwest China based on tree rings

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Journal of Geographical Sciences 2024年第1期34卷 146-164页

作者： WU Xuan JIAO liang DU Dashi xue Ruhong WEI Mengyuan zhang Peng College of Geography and Environment Science Northwest Normal UniversityLanzhou 730070China Key Laboratory of Resource Environment and Sustainable Development of Oasis Northwest Normal UniversityLanzhou 730070China

Current ecosystem models used to simulate global terrestrial carbon balance generally suggest that terrestrial landscapes are stable and mature,but terrestrial net primary productivity(NPP)data estimated without accounting for disturbances in species composition,environment,structure,and ecological characteristics will reduce the accuracy of the global carbon ***,the steady-state assumption and neglect of elevation-related changes in forest NPP is a *** Qilian Mountains are located in continental climate zone,and vegetation is highly sensitive to climate *** quantified aboveground biomass(AGB)and aboveground net primary productivity(ANPP)sequences at three elevations using field-collected tree rings of Picea crassifolia in Qilian Mountains of Northwest *** results showed that(1)There were significant differences between AGB and ANPP at the three elevations,and the growth rate of AGB was the highest at the low elevation(55.99 t ha^(–1)10a^(–1)).(2)There are differences in the response relationship between the ANPP and climate factors at the three elevations,and drought stress is the main climate signal affecting the change of ANPP.(3)Under the future climate scenario,drought stress intensifies,and the predicted decline trend of ANPP at the three elevations from mid-century to the end of this century is–0.025 t ha^(–1)10a^(–1),respectively;–0.022 t ha^(–1)10a^(–1);At–0.246 t ha^(–1)10a^(–1),the level of forest productivity was significantly *** results reveal the elevation gradient differences in forest productivity levels and provide key information for studying the carbon sink potential of boreal forests.

关键词： global climate change tree ring aboveground net primary productivity aboveground biomass drought stress Qilian Mountains

Price Mechanism,Government Constraints and Carbon Trading Pilot Policy for Emission Reduction

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Data Intelligence 2024年第3期6卷 621-648页

作者： Wei Huang Haili xue Qin zhang Haoguang liang University of Chinese Academy of Sciences 100190China National Science Library Chinese Academy of Sciences100190China China Center for Modernization Research 100190China Beijing Key Laboratory of National Belt and Road Data Analysis and Decision Support 100024China

Based on the data of 247 cities at the prefecture level in China from 2007 to 2019,this paper analyzes the impact of the carbon emissions trading(CET)pilot policy on carbon emission reduction from the perspective of the price mechanism and government *** results show that the carbon emissions and carbon intensity in the pilot areas are significantly reduced by adjusting the industrial structure and promoting green technology *** terms of regions,the emission reduction effect of the pilot policy in regions with a high proportion of industry is obviously weaker than that in other *** aim of the carbon emission trading policy in China that achieve carbon emission reduction is by coordinating the carbon emission trading price that fail to fulfill this aim independently and the degree of government punishment for enterprises.

关键词： Carbon emission reduction Double difference Price incentive mechanism Government restraint mechanism

Operando measurement of lattice deformation profiles of synchrotron radiation monochromator

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Nuclear Science and Techniques 2024年第7期35卷 8-19页

作者： Yue zhang Zhong-liang Li Shang-Yu Si Lian xue Hong-Xin Luo Xiao-Wei zhang Jun Hu Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201204China ShanghaiTech University Shanghai201210China University of the Chinese Academy of Sciences Beijing100049China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing100049China

This study presents a new method for characterizing the thermal lattice deformation of a monochromator with high precision under service conditions and first reports the operando measurements of nanoscale thermal lattice deformation on a double-crystal monochromator at different incident *** nanoscale thermal lattice deformation of the monochromator first crystal was obtained by analyzing the intensity of the distorted DuMond *** diagrams of the 333 diffraction index,sensitive to lattice deformation,were obtained directly using a 2D detector and an analyzer crystal orthogonal to the *** increasing incident power and power density,the maximum height of the lattice deformation increased from 3.2 to 18.5 nm,and the deformation coefficient of the maximum height increased from 1.1 to 3.2 nm/*** maximum relative standard deviation was 4.2%,and the maximum standard deviation was 0.1 *** on the measured thermal deformations,the flux saturation phenomenon and critical point for the linear operation of the monochromator were predicted with increasing incident *** study provides a simple solution to the problem of the lower precision of synchrotron radiation monochromator characterizations compared to simulations.

关键词： Synchrotron radiation Monochromator Lattice deformation X-ray dynamic diffraction

Bivariate Real-valued Box-spline Orthogonal Periodic Wavelets

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Northeastern Mathematical Journal 2006年第1期22卷 21-29页

作者：李强梁学章 Institute of Mathematics Jilin University Changchun 130012

In this paper, we construct a kind of bivariate real-valued orthogonal periodic box-spline wavelets. There are only 4 terms in the two-scale dilation equations. This implies that the corresponding decomposition and reconstruction algorithms involve only 4 terms respectively which are simple in practical computation. The relation between the periodic wavelets and Fourier series is also discussed.

关键词： box-spline periodic wavelet Fourier series

Improving treatment plan and mental health in children with abdominal infection for broad-spectrum bacterial infections

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World Journal of Psychiatry 2024年第9期14卷 1319-1325页

作者： Gui-Bo Wang xue-Feng zhang Bing liang Jie Lei Jun xue Department of Pediatric Surgery the First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Department of General Surgery the First Affiliated Hospital of Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina

BACKGROUND Pediatric abdominal infection is a common but serious disease that requires timely and effective *** surgical treatment,accurate diagnosis and rational application of antibiotics are the keys to improving treatment *** To investigate the effect of broad-spectrum bacterial detection on postoperative antibiotic *** A total of 100 children with abdominal infection who received surgical treatment in our hospital from September 2020 to July 2021 were *** observation group collected blood samples upon admission and sent them for broad-spectrum bacterial infection nucleic acid testing,and collected pus or exudate during the operation for bacterial culture and drug sensitivity testing;the control group only sent bacterial culture and drug sensitivity testing during the *** White blood cell count,C-reactive protein,procalcitonin,3 days after surgery,showed better postoperative index than the control group(P<0.05).The hospital stay in the observation group was significantly shorter than that in the control *** hospitalization cost in the observation group was significantly lower than that in the control group,and the difference between the two groups was statistically significant(P<0.05).CONCLUSION Early detection of broad-spectrum bacterial infection nucleic acids in pediatric abdominal infections can help identify pathogens sooner and guide the appropriate use of antibiotics,improving treatment outcomes and reducing medical costs to some extent.

关键词： Pediatric abdominal infection Nucleic acid detection of broad-spectrum bacterial infection Bacterial culture Drug sensitivity testing Treatment effect Cost Mental health

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-liang Xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu zhang xue-Quan zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity