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Journal of Computational Mathematics 2023年第3期41卷 501-524页

作者： xiaolin Li School of Mathematical Sciences Chongqing Normal UniversityChongqing 400047China

Numerical integration poses greater challenges in Galerkin meshless methods than finite element methods owing to the non-polynomial feature of meshless shape *** reproducing kernel gradient smoothing integration(RKGSI)is one of the optimal numerical integration techniques in Galerkin meshless methods with minimum integration *** this paper,properties,quadrature rules and the effect of the RKGSI on meshless methods are *** existence,uniqueness and error estimates of the solution of Galerkin meshless methods under numerical integration with the RKGSI are established.A procedure on how to choose quadrature rules to recover the optimal convergence rate is presented.

关键词： Galerkin meshless method Numerical integration Quadrature rule Error estimates Element-free Galerkin method Degree of precision

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全子宫切除术患者围手术期输血研究

中国输血杂志 2021年第1期34卷 29-31页

作者：范亚欣毕晓琳李宁刘俊张婵马晓露王忠利高艳大连市血液中心辽宁大连116001 大连市妇幼保健院大连医科大学附属第一医院大连医科大学附属第二医院大连市中心医院

目的分析全子宫切除术患者围手术期影响输血的相关因素,探讨减少异体血输注的有效措施,并为建立全子宫切除术单病种临床输血评价考核指标提供依据。方法选取大连地区3家三级甲等综合医院和1家妇幼保健院接受全子宫切除术患者747例,分为... 详细信息

目的分析全子宫切除术患者围手术期影响输血的相关因素,探讨减少异体血输注的有效措施,并为建立全子宫切除术单病种临床输血评价考核指标提供依据。方法选取大连地区3家三级甲等综合医院和1家妇幼保健院接受全子宫切除术患者747例,分为输血组(69例)和未输血组(678例);收集747例全子宫切除术患者的基本信息、手术相关信息、术前血常规、术后转归情况、围手术期输血量,进行统计学分析。结果全子宫切除术患者围手术期输血比例为9.2%(69/747),人均红细胞用血量(0.4±2.1)U。输血组和未输血组在年龄、手术时间、术中失血量、术前Hb浓度、住院天数、抗生素使用种类和天数方面的差异P<0.05,均有统计学意义,数值分别为(49.7±9.1)和(53±9.5)岁、(182.7±83.5)和(119.5±64.8)min、(603±650)和(160±173)mL、(96±26)和(124±18)g/L、(9.3±4.8)和(7.3±3.9)d、(2.2±1.1)和(1.6±0.7)种、(6.0±3.9)和(4.4±2.2)d。患者围手术期输血量与术中失血量、手术时间和术前Hb浓度显著相关,相关系数分别为0.004、0.002、-0.022。结论应加强全子宫切除术的患者血液管理,通过提高术前Hb水平、减少手术时间和术中失血量来降低异体血的输注,改善患者预后。

关键词：全子宫切除术围手术期输血患者血液管理

新工科项目式教学PPS考核评价方法研究——以《3D基础造型》课程为例

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办公自动化 2025年第1期30卷 28-30页

作者：梁晓琳山东华宇工学院设计与艺术学院德州253034

项目式教学是软件类课程教学的有效途径,《3D基础造型》课程以产业需求为切入点,改革教学设计并优化评价考核方式。为综合考察学生在知识、能力、素质等方面的表现,提出以学生学习效果为中心的PPS评价方法,这是贯通课程始终的一种全链... 详细信息

项目式教学是软件类课程教学的有效途径,《3D基础造型》课程以产业需求为切入点,改革教学设计并优化评价考核方式。为综合考察学生在知识、能力、素质等方面的表现,提出以学生学习效果为中心的PPS评价方法,这是贯通课程始终的一种全链条式的考核评价体系,使各评价环节全面覆盖课程目标并充分考虑学生需求,评价过程和结果公开、透明。实践证明,项目式教学与新的评价方式使学生综合能力得到显著的提升。

关键词：新工科 PBL教学 PPS考核评价

Meshless acoustic analysis using a weakly singular Burton-Miller boundary integral formulation

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Applied Mathematics and Mechanics(English Edition) 2020年第12期41卷 1897-1914页

作者： Linchong CHEN xiaolin LI School of Mathematics and Information Engineering Chongqing University of EducationChongqing 400065China School of Mathematical Sciences Chongqing Normal UniversityChongqing 400047China

The Burton-Miller boundary integral formulation is solved by a complex variable boundary element-free method(CVBEFM)for the boundary-only meshless analysis of acoustic problems with arbitrary *** regularize both strongly singular and hypersingular integrals and to avoid the computation of the solid angle and its normal derivative,a weakly singular Burton-Miller formulation is derived by considering the normal derivative of the solid angle and adopting the singularity subtraction *** facilitate the implementation of the CVBEFM and the approximation of gradients of the boundary variables,a stabilized complex variable moving least-square approximation is selected in the meshless discretization *** results show the accuracy and efficiency of the present CVBEFM and reveal that the method can produce satisfactory results for all wavenumbers,even for extremely large wavenumbers such as k=10000.

关键词： meshless method complex variable moving least-square approximation boundary element-free method Burton-Miller formulation regularization high frequency acoustic problem large wavenumber

Random stability for lateral vibration on footbridge based on IEVIE-PDE method

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Earthquake Engineering and Engineering Vibration 2021年第4期20卷 981-992页

作者： Jia Buyu Yu xiaolin School of Civil Engineering and Transportation South China University of TechnologyGuangzhou 510640China Newmark Structural Engineering Laboratory University of Illinois at Urbana-ChampaignUrbana 61801USA

The pedestrian-induced lateral vibration of footbridges is essentially classified as a nonlinear stochastic ***,bridge vibration stability falls within the field of nonlinear stochastic vibration *** present,the Lyapunov method is mainly used to analyze such ***,this method is qualitative,and it cannot quantitatively analyze the vibration stability *** this study,a new analytical method based on a comparison of the input energy and the variation of intrinsic energy(IEVIE)is used to analyze the nonlinear stochastic vibration stability of the lateral vibration of the *** improved Nakamura model is used to describe the lateral nonlinear stochastic vibration of the footbridge.A combination of the IEVIE method and the probability density evolution(PDE)method is then proposed,in which the IEVIE method is utilized to determine vibration *** PDE method is used to obtain the reliability of vibration *** proposed method is successfully applied to the Millennium Bridge,and its effectiveness is verified by comparing the Monte Carlo and Lyapunov *** proposed method can obtain the dynamic probability of the vibration as stable or instable and provide a reference for quantitative analysis of lateral nonlinear stochastic vibration stability of footbridges.

关键词： footbridge lateral vibration stochastic stability quantitative

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不同自体输血方式的临床效果研究

国际输血及血液学杂志 2017年第4期40卷 302-309页

作者：徐爽周俊范亚欣郑井滨王东博尹志群毕晓琳高艳辽宁省大连市血液中心 116001 北京军区总医院 100700 辽宁省大连市中心医院 116033

目的探讨不同自体输血方式的有效性，促进医疗机构开展自体输血工作，保障临床输血安全。方法采用简单随机抽样法随机选择2014年1月至2016年7月，于北京军区总医院或大连中心医院行骨科手术的88例自体输血患者作为研究对象。采用简单随... 详细信息

目的探讨不同自体输血方式的有效性，促进医疗机构开展自体输血工作，保障临床输血安全。方法采用简单随机抽样法随机选择2014年1月至2016年7月，于北京军区总医院或大连中心医院行骨科手术的88例自体输血患者作为研究对象。采用简单随机分组法，将其随机分为，术中自体红细胞回输组（n=43），储存式自体全血回输组（n=25）及储存式自体单采红细胞回输组（n=20）。采用简单随机抽样法，选择同期42例于受试者收集医院行骨科手术，并且术中仅接受异体输血的患者，纳入对照组（n=42）。记录并分析采血前／术前、输血后当天、输血后第4天，各组患者红细胞计数、血红蛋白（Hb）水平、血细胞比容（HCT）、血小板计数，以及患者住院天数、术中出血量、异体输血量等指标。采用统计学方法比较4组患者上述各项指标的差异。结果①本研究4组患者采血前／术前的红细胞计数、Hb水平、HCT、血小板计数分别比较，差异均无统计学意义（P〉0．05）。②输血后当天：4组患者的红细胞计数、Hb水平、HCT分别比较，差异均无统计学意义（P〉0．05）；4组患者的血小板计数比较，差异有统计学意义（F=4．157，P=0．008）。其中，储存式自体全血回输组患者的血小板计数最高[（196．0±43．8）×10^9／L]，高于术中自体红细胞回输组、对照组，并且差异均有统计学意义（P=0．004、0．009）；但是，与储存式自体单采红细胞回输组比较，差异无统计学意义（P=0．653）。③输血后第4天：4组患者的红细胞计数比较，差异无统计学意义（P〉0．05）；4组患者的Hb水平比较，差异有统计学意义（F=3．764，P=0．013）。其中，术中自体红细胞回输组的Hb水平最高[（115．6±23．8）g／L]，高于储存式自体全血回输组及对照组，并且差异均有统计学意义（P=0．022、0．006）；但是，与储存式自体单采红细胞回输组比较，差异无统计学意义（P=0．878）。4组患者的HCT比较，差异有统计学意义（F=3．915，P=0．011）。其中，储存式自体单采红细胞回输组HCT最高[（34．4±4．8）％]，高于对照组，并且差异有统计学意义（P=0．012）；但是，与储存式自体全血回输组及术中自体红细胞回输组分别比较，差异均无统计学意义（P=0．059、0．819）。④4组患者术中出血量和异体输血量分别比较，差异均无统计学意义（P〉0．05）。4组患者住院天数比较，差异有统计学意义（x^2=11．990，P=0．007）。其中，对照组患者的住院天数最长[14．5d（9．5～16．0d）]，长于储存式自体全血回输组，并且差异有统计学意义（P=0．007）；但是，与储存式自体单采红细胞回输注及术中自体红细胞回输组分别比较，差异均无统计学意义（P=0．09、0．944）。结论临床择期外科手术患者的自体输血方式，首选储存式自体单采红细胞回输，其次为储存式自体全血回输和术中自体红细胞回输。在不能达到自体输血要求时，可选择异体输血。临床医师需要转变观念，逐步降低异体输血率，广泛、有效地开展自体输血工作，进一步保障临床输血安全。

关键词：输血,自体血液成分输血单采红细胞异体输血

Composition Engineering Opens an Avenue Toward Efficient and Sustainable Nitrogen Fixation

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Energy & Environmental Materials 2024年第1期7卷 313-325页

作者： xiaolin Wang Liming Yang Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationWuhan 430074China Hubei Key Laboratory of Materials Chemistry and Service Failure Wuhan 430074China Hubei Key Laboratory of bioinorganic Chemistry and Materia Medica Wuhan 430074China Hubei Engineering Research Center for biomaterials and Medical Protective Materials Wuhan 430074China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China

In this work,we open an avenue toward rational design of potential efficient catalysts for sustainable ammonia synthesis through composition engineering strategy by exploiting the synergistic effects among the active sites as exemplified by diatomic metals anchored graphdiyne via the combination of hierarchical high-throughput screening,first-principles calculations,and molecular dynamics *** 43 highly efficient catalysts feature ultralow onset potentials(|U_(onset)|≤0.40 V)with Rh-Hf and Rh-Ta showing negligible onset potentials of 0 and-0.04 V,*** high catalytic activities of Rh-Hf and Rh-Ta can be ascribed to the synergistic *** forming heteronuclears,the combinations of relatively weak(such as Rh)and relatively strong(such as Hf or Ta)components usually lead to the optimal strengths of adsorption Gibbs free energies of reaction *** origin can be ascribed to the mediate d-band centers of Rh-Hf and Rh-Ta,which lead to the optimal adsorption strengths of intermediates,thereby bringing the high catalytic *** work provides a new and general strategy toward the architecture of highly efficient catalysts not only for electrocatalytic nitrogen reduction reaction(eNRR)but also for other important *** expect that our work will boost both experimental and theoretical efforts in this direction.

关键词： composition engineering strategy diatomic catalysts electrocatalytic nitrogen reduction reaction first-principles calculations graphdiyne hierarchical high-throughput screening synergistic effects

Subgroup Analysis for Longitudinal Data via Semiparametric Additive Mixed Effects Model

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Journal of Systems Science & Complexity 2023年第5期36卷 2155-2185页

作者： BO xiaolin ZHANG Weiping Department of Statistics and Finance University of Science and Technology of ChinaHefei 230026China

This paper proposed a general framework based on semiparametric additive mixed effects model to identify subgroups on each covariate and estimate the corresponding regression functions simultaneously for longitudinal data,thus it could reveal which covariate contributes to the existence of subgroups among population.A backfitting combined with k-means algorithm was developed to detect subgroup structure on each covariate and estimate each semiparametric additive component across subgroups.A Bayesian information criterion is employed to estimate the actual number of *** efficacy and accuracy of the proposed procedure in identifying the subgroups and estimating the regression functions are illustrated through numerical *** addition,the authors demonstrate the usefulness of the proposed method with applications to PBC data and Industrial Portfolio's Return data and provide meaningful partitions of the populations.

关键词： Additive model backfitting mixed effects subgroup identification

GNSS Fault Detection and Exclusion Based on Virtual Pseudorange-Based Consistency Check Method

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Chinese Journal of Electronics 2020年第1期29卷 41-48页

作者： LIU Jiang ZHAO xiaolin School of Electronic and Information Engineering Beijing Jiaotong University Beijing Engineering Research Center of EMC and GNSS Technology for Rail Transportation

Although there have been many implementations of Global navigation satellite system(GNSS)in rail transport systems, the integrity assurance of GNSS positioning is still not highly concerned by the *** is a significant issue for specific safety-relevant GNSS railway applications, especially the railway signaling system which requires a critical safety level. Classical integrity monitoring solutions require an acceptable satellite visibility level to carry out Fault detection and exclusion(FDE), and this restriction leads to a degraded availability of FDE and final position computation. In order to break the limitation by satellite visibility, a consistency check method for FDE is proposed based on the virtual satellite pseudorange data, which is established based on the track database. Results from simulations show that the presented method can detect and exclude different types of faults effectively. Compared with classical residualbased GNSS integrity monitoring algorithm, the presented method achieves a higher FDE availability and makes better use of the satellite measurements even under the limited GNSS observing conditions.

关键词： Satellite navigation Integrity monitoring Fault detection Fault exclusion Railway train control

EXPLAINING THE CHANGES IN ALPS BY IDENTIFYING ALPS-IMPORTANT COEFFICIENTS:AN EMPIRICAL APPLICATION OF CHINA

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Journal of Systems Science & Complexity 2013年第3期26卷 383-406页

作者： LU xiaolin XU Jian Management School University of Chinese Academy of Sciences

This paper establishes the relation between APLs and direct input coefficients through Sherman-Morrison *** such a basis,elasticity matrix can be calculated for each element of the APLs matrix,which measures the percentage change in the APLs-matrix element brought by one percentage change in every direct input ***,the percentage change in each APLs-matrix element caused by the real percentage change in each coefficient with other coefficients fixed can be drawn,from which it is easily to find out the APLs-important coefficients and is useful to explain the reason for change in the *** empirical application studies the Chinese ***'s more,the method is applied under different level of *** comparison between the APLs matrix of 1997 and 2002 allows the authors to visualize the elements that change *** the methodology above is applied to explain the change from the perspective of direct input coefficients and find out the important coefficients to the Chinese APLs matrix.

关键词： APLs-important coefficients APLs matrix direct input coefficients elasticity matrix Sherman-Morrison formulation.