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基于高斯函数拟合的多维数据三维可视化仿真

计算机仿真 2024年第1期41卷 206-210页

作者：裴庆庆刘慧慧郑州工业应用技术学院信息工程学院河南郑州451150 河南理工大学计算机科学与技术学院河南焦作454002

为了得到满意的多维数据可视化效果,提出一种基于四叉树的多维数据三维可视化方法。采用随机森林和转导推理相结合的方式提取多维数据特征,通过四叉树对多维数据特征简化处理,降低数据处理难度。将简化处理后的多维数据特征点作为热点,... 详细信息

为了得到满意的多维数据可视化效果,提出一种基于四叉树的多维数据三维可视化方法。采用随机森林和转导推理相结合的方式提取多维数据特征,通过四叉树对多维数据特征简化处理,降低数据处理难度。将简化处理后的多维数据特征点作为热点,利用高斯函数拟合计算各个热点对周围数据产生的作用值,将全部热点的作用值累加,将累加值作为最终的热度值,采用光线投射方法展开三维图绘制,最终实现多维数据三维可视化。经实验测试证明,采用所提方法可以有效提升多维数据三维可视化效果的分辨率,减少内存损耗,提升执行效率。

关键词：特征提取四叉树多维数据三维可视化

基于工程教育专业认证的工程造价专业课程体系重构探析

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蚌埠学院学报 2024年第4期13卷 95-101页

作者：王志远刘惠惠唐根丽安徽财经大学管理科学与工程学院安徽蚌埠233030

为适应行业发展对工程造价专业学生岗位能力的要求,在总结归纳工程教育专业认证文件要求和“注册造价工程师”执业资格考试制度要求的基础上,分析工程造价专业应开设课程的科目、学时、顺序等设置问题,结合地方财经类院校本科层次工程... 详细信息

为适应行业发展对工程造价专业学生岗位能力的要求,在总结归纳工程教育专业认证文件要求和“注册造价工程师”执业资格考试制度要求的基础上,分析工程造价专业应开设课程的科目、学时、顺序等设置问题,结合地方财经类院校本科层次工程造价专业办学特点,以安徽财经大学工程造价专业为例,对工程造价专业的课程体系进行调整设置,修订后的课程体系较大程度地响应了认证和资格考试要求,课程体系重构方案可为同类院校教学改革提供参考。

关键词：工程教育专业认证工程造价专业课程体系执业资格财经类高校

经皮穴位电刺激联合中医情志干预对腹腔镜直肠癌根治术患者免疫功能和心理应激的影响

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广州中医药大学学报 2024年第4期41卷 951-958页

作者：彭美玉丘景妮郑文戈刘慧慧广州中医药大学第一附属医院广东广州510405

【目的】评价经皮穴位电刺激(TEAS)联合中医情志干预对腹腔镜直肠癌根治术患者免疫功能和心理应激的影响。【方法】将100例住院拟行腹腔镜直肠癌根治术治疗的患者随机分为A、B、C、D 4组,每组各25例。A组给予麻醉前TEAS 30 min,B组给予... 详细信息

【目的】评价经皮穴位电刺激(TEAS)联合中医情志干预对腹腔镜直肠癌根治术患者免疫功能和心理应激的影响。【方法】将100例住院拟行腹腔镜直肠癌根治术治疗的患者随机分为A、B、C、D 4组,每组各25例。A组给予麻醉前TEAS 30 min,B组给予持续TEAS至手术结束,C组给予麻醉前TEAS 30 min+中医情志干预,D组给予持续TEAS至手术结束+中医情志干预,其中,TEAS取穴足三里(双侧)、三阴交(双侧)、百会、内关(双侧)。观察各组围术期指标以及术前与术后3 d免疫功能指标、Th1/Th2细胞分子机制、心理应激反应指标的变化情况,并比较各组的不良反应发生情况。【结果】(1)围术期指标方面,4组患者的手术时间、出血量、输液量比较,差异均无统计学意义(P>0.05);D组的舒芬太尼用量、瑞芬太尼用量、术后苏醒时间、术后24 h痛觉模拟量表(VAS)评分均低于A组、B组、C组(P<0.05),而B组、C组的上述指标均低于A组(P<0.05)。(2)免疫功能指标方面,D组术后3 d的T淋巴细胞亚群CD3+、CD4+及自然杀伤(NK)细胞水平均高于A组、B组、C组(P<0.05),而B组、C组的上述指标均高于A组(P<0.05)。(3)Th1/Th2细胞分子机制方面,D组术后3 d的血清白细胞介素2(IL-2)、γ干扰素(IFN-γ)水平均高于A组、B组、C组(P<0.05),血清白细胞介素10(IL-10)水平均低于A组、B组、C组(P<0.05),而B组、C组的血清IL-2、IFN-γ水平均高于A组(P<0.05),血清IL-10水平均低于A组(P<0.05)。(4)心理应激反应指标方面,D组术后3 d的焦虑自评量表(SAS)和抑郁自评量表(SDS)评分均低于A组、B组、C组(P<0.05),而B组、C组的上述评分均低于A组(P<0.05)。(5)不良反应方面,A组出现1例恶心呕吐,B组出现2例恶心呕吐、1例头晕,C组无不良反应,D组出现1例恶心呕吐,不良反应发生率分别为4.0%(1/25)、12.0%(3/25)、0.0%(0/25)、4.0%(1/25),组间比较,差异无统计学意义(χ2=0.400,P=0.527)。【结论】针对腹腔镜直肠癌根治术患者,TEAS联合中医情志干预可有效调节患者围术期免疫功能,减轻应激反应,缓解患者紧张焦虑状态,同时可产生一定的镇痛作用,减少阿片类药物用量,提高患者围术期舒适度及手术耐受水平。

关键词：直肠癌根治术经皮穴位电刺激(TEAS) 中医情志干预免疫功能心理应激反应

Vibration attenuation performance of wind turbine tower using a prestressed tuned mass damper under seismic excitation

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 511-524页

作者： Lei Zhenbo liu Gang Wang hui hui Yi School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing 400045China

With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly *** particular,seismic excitation can create a resonance response and cause excessive vibration of the *** investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this ***,a mathematical model is established based on structural dynamics under seismic ***,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning ***,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal ***,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the *** addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.

关键词： wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation

碳纤维增强聚碳酸酯复合材料在高温中的准静态压缩强度

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纺织科学与工程学报 2024年第1期41卷 34-40页

作者：李嘉刘慧慧曹文静顾伯洪孙宝忠东华大学纺织学院上海201620

选择碳纤维平纹织物、碳纤维单向布分别和聚碳酸酯制备热塑性复合材料,包括碳纤维增强聚碳酸酯平纹层合板、单向板和正交层合板,并自制的高温装置与MTS(Material Testing System)搭配使用,研究上述三种复合材料在20℃、120℃、150℃、18... 详细信息

选择碳纤维平纹织物、碳纤维单向布分别和聚碳酸酯制备热塑性复合材料,包括碳纤维增强聚碳酸酯平纹层合板、单向板和正交层合板,并自制的高温装置与MTS(Material Testing System)搭配使用,研究上述三种复合材料在20℃、120℃、150℃、180℃四种温度下的面外准静态压缩行为,分析结构和温度对性能的影响,探究不同条件下的失效模式。结果表明:碳纤维增强聚碳酸酯平纹层合板的最大应力值和压缩模量与正交层合板接近,均高于碳纤维增强聚碳酸酯单向板;且温度对三种复合材料的面外准静态压缩性能有很大影响,随温度升高,准静态压缩模量和最大应力值都减小。

关键词：聚碳酸酯热塑性高温准静态压缩

An integrative mathematical model of microwave ion thruster for mHz-frequency thrust noise analysis

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Chinese Journal of Aeronautics 2024年第4期37卷 121-136页

作者： Xiang NIU hui liu Daren YU Plasma Propulsion Laboratory Harbin Institute of TechnologyHarbin 150001China

Many high-precision space missions need thrusters to produce thrust with low noise to compensate for disturbances and ensure satellite platform stability. Microwave ion thruster is characterized with a wide thrust range and potential for these missions. A cost-effective and accurate mathematical model is crucial for mHz-frequency thrust noise analysis and feedback controller design. The Particle-In-Cell(PIC) and global models are two common simulation tools. The PIC model is characterized with high accuracy but huge computation cost, which is difficult to analyze long-time performance characteristics. Now, the global model is only used for the discharge chamber with low accuracy and cannot reflect ion extraction properties. In this paper, an integrative mathematical model is built for a 1-cm microwave ion thruster and can reflect ion beamlet divergence and impingement on the Accelerator Grid(AG). Simulation results show good agreement with experiments at 0.06 sccm. However, the model demonstrates worse consistency with experiments when the flux increases to 0.1 sccm, which may be because the influence of neutral gas on the Electron Cyclotron Resonance(ECR) is not considered in the model. A long-time(1000 s) simulation is conducted with this model under 35 μN. It takes 3 hrs, and the thrust noise reaches 1 μN/Hz^(0.5) at 1 mHz.

关键词： Electric propulsion Microwave ion thruster Integrative model Sheath property Ion beamlet divergence Thrust noise Plasma

Enlarged interlayer of separator coating enabling high-performance lithiumsulfur batteries

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 103-112页

作者： Yanqi Feng hui liu Xiaoting liu Qiongqiong Lu School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450001China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW) Dresden e.V.Dresden 01069Germany

Lithiumsulfur batteries have been intensively studied due to their high theoretical energy density and abundant sulfur resources. However, their commercial application is hindered by the low redox kinetics and high sulfur losses. In principle, in the design of cathodes and separators, the adsorption toward lithium-polysulfides should be enhanced and the conversion of soluble high-order lithium-polysulfides should be catalyzed. Herein, a KV_(3)O_(8)·0.75H_(2)O separator is designed as an effective lithium-polysulfides mediator in lithiumsulfur batteries. The intercalated K+ would enlarge the interlayer spacing of vanadium oxides, preventing the collapse of the layer structure and improving the electrical/ion conductivity of the interface. Moreover, the KV_(3)O_(8)·0.75H_(2)O modified separator possess a prior adsorption and high redox kinetics toward lithium-polysulfides due to the enhanced diffusion kinetics, which guarantees the high-rate capability and efficient utilization of sulfur. As a result, lithiumsulfur batteries exhibit a high capacity of 1362 mAh·g^(-1) and a long lifespan with a low capacity loss of 0.073% per cycle. This work may provide an alternative way to establish a functional separator to balance the adsorption and conversion of polysulfides during the redox back and forth.

关键词： lithium kinetics adsorption

Regulation of solvation structure and the cooperation environment of potassium bonds for wider-temperature adaptive potassium storage

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Rare Metals 2024年第4期43卷 1610-1621页

作者： Bing-Bing liu Yi-hui liu You-Bin Zhang Zhen-Guo Qi Guo-hui Qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdao266042China Shandong Synergetic Innovation Center of Ecological and Chemical Engineering Qingdao266042China

Antimony selenide(Sb_(2)Se_(3))is one of the perspective candidates for potassium-ion batteries due to its advanced virtues stem including featured high capacity,fertile reserves and the relative narrow band *** the unique advantages,it is still plagued by the unstable interface compatibility and poor wider-temperature *** optimization of microstructure and the construction of inorganic-organic hybrids with a low desolvation barrier and rapid kinetics behaviors are efficient to address these *** Sb_(2)Se_(3)nanorods enclosed by the S-doped carbon layer(SC),further crosslinked by the poly(N-isopropylacrylamide)(PM)film(PM@Sb_(2)Se_(3)@SC),were artificially fabricated,and it displays the enrichment ion aggregated model as well as contacted ion pair state,the well-tailored cooperation environment of potassium bonds,assuring a homogeneous potassium deposition and an excellent widertemperature *** complicated experimental studies and theoretical calculations authenticate the synergistic effects of geometric conformation and compositional design for the tremendously enhanced potassium ***,the full device over PM@Sb_(2)Se_(3)@SC anode and the potassium Prussian blue cathode manifests impressively durable cycling life and wider-temperature adaptability,verifying the glorious contribution from the finely manipulation in solvation structure and potassium bonds to enhancing the potassium storage behaviors.

关键词： Anode Sb_(2)Se_(3) rods Interface compatibility Inorganic-organic electrode Potassium ion battery

Generic Existence of Infinitely Many Non-contractible Closed Geodesics on Compact Space Forms

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1674-1684页

作者： hui liu Yu Chen Wang School of Mathematics and Statistics Wuhan UniversityWuhan430072P.R.China School of Mathematics Tianjin Normal UniversityTianjin300384P.R.China

Let M=S^(n)/Γand h be a nontrivial element of finite order p inπ_(1)(Μ),where the integers n,p≥2,Γis a finite abelian group which acts freely and isometrically on the n-sphere and therefore M is diffeomorphic to a compact space *** this paper,we prove that there are infinitely many non-contractible closed geodesics of class[h]on the compact space form with C^(r)-generic Finsler metrics,where 4≤r≤∞.The conclusion also holds for Cr-generic Riemannian metrics for 2≤r≤∞.The proof is based on the resonance identity of non-contractible closed geodesics on compact space forms.

关键词： Compact space forms non-contractible closed geodesics generic Finsler metrics resonance identity