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Science China Materials 2024年第10期67卷 3236-3244页

作者： Zhihao Liu Xin Wen Yingchen Xie fengfei wang Li wang Yu Wu Xuning Feng School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials under Shock and Impact Beijing Institute of TechnologyBeijing 100081China China North Standardization Center Beijing 100089China State Key Laboratory of Intelligent Green Vehicle and Mobility Tsinghua UniversityBeijing 100084China Rocket Force University of Engineering Xi’an 710025China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

With the continuous development of the electrification industry,the development of high-specific batteries has attracted much ***,the safety of lithiumion batteries is currently unable to meet the market demand due to poor thermal *** the thermal issues is crucial to improve battery *** carbonate(EC)not only plays an important interfacial film-forming role,but also poses safety risks in terms of *** this work,we conducted a series of gradient experiments utilizing different EC amounts and verified the effect of reducing EC on battery performance.A strategy is also proposed to design a new *** methyl carbonate(EMC)is used instead of EC as the main solvent to improve the thermal safety of the battery,while salts and additives are used to dominate the film formation to improve the cycling stability of the battery under high voltages(4.5 V,~90%after 200 cycles).This work paves a new avenue for the development of novel electrolyte systems.

关键词： lithium-ion batteries safety ethylene carbonate high voltage electrolyte

区域经济导向下地方高校MBA“三螺旋”实践教学的价值机理

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河北工程大学学报（社会科学版） 2024年第2期41卷 116-121页

作者：王凤飞河北经贸大学工商管理学院河北石家庄050061

地方高校MBA实践教学应该是区域经济导向下依托专业理论素养的管理创新能力培养,其核心理念是以产出为导向,加强与外部联动,充分发挥区域内政府、行业、企业和高校在管理实践教学方面的内在一致性和相互支撑性。通过本质、现实、价值三... 详细信息

地方高校MBA实践教学应该是区域经济导向下依托专业理论素养的管理创新能力培养,其核心理念是以产出为导向,加强与外部联动,充分发挥区域内政府、行业、企业和高校在管理实践教学方面的内在一致性和相互支撑性。通过本质、现实、价值三重维度变革,理论层面上,实现目标协同、政策互补、教学范式创新的机理,实践层面上,实现要素协同、资源互补、能力培养创新的机理,共同引导、驱动地方高校MBA实践教学培养模式的嬗变,让高端MBA精英管理教育走出象牙塔,推动MBA人才链、行业链、创新链、社会链的有机衔接。

关键词：区域经济地方高校MBA 实践教学

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句子级时序卷积网络的多模态抑郁症识别方法

中北大学学报（自然科学版） 2024年第3期45卷 274-285页

作者：王烽飞卓广平周金保刘国强张光华太原师范学院计算机科学与技术学院山西晋中030619 太原学院智能与自动化系山西太原030032

针对多模态抑郁症模型在特征提取时,语句间关联性较弱,不同模态间的特征融合较为随意,在中文数据集上模型的泛化能力缺乏验证等问题,本文通过分析与抑郁症相关的音频、文本和视觉特征,提出了基于改进TCN模型的多模态抑郁症识别模型STCMN... 详细信息

针对多模态抑郁症模型在特征提取时,语句间关联性较弱,不同模态间的特征融合较为随意,在中文数据集上模型的泛化能力缺乏验证等问题,本文通过分析与抑郁症相关的音频、文本和视觉特征,提出了基于改进TCN模型的多模态抑郁症识别模型STCMN(Sentence-level Temporal Convolutional Memory Net-work),并将该模型应用于临床抑郁症辅助诊断当中。该模型首先使用残差块、GRU和Self-Attention的融合模块来提取不同模态下的句子级特征,增强了上下文联系,然后使用TCN模型来提取不同模态的全局特征,并使用Cross Attention对不同模态的全局特征以多模态融合特征为主进行融合,最后通过LogSoftmax层得到模型对抑郁症的识别结果。在DAIC-WOZ公开数据集上,本文所提出的方法对抑郁症识别的准确率达到了91.3%,精确率达到了93.6%,召回率达到了89.7%,其相关指标均优于其他方法,可以更好地满足临床医学的需求。在私有中文数据集MMD2022上,STCMN模型的识别结果仍为最优,表明该模型在中文抑郁症识别任务上具较好的泛化能力。

关键词：抑郁症时序卷积网络门控循环单元自注意力机制交叉注意力机制

Remaining useful life prediction based on nonlinear random coefficient regression model with fusing failure time data

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Journal of Systems Engineering and Electronics 2023年第1期34卷 247-258页

作者： wang fengfei TANG Shengjin SUN Xiaoyan LI Liang YU Chuanqiang SI Xiaosheng Department of Mechanical Engineering Rocket Force University of EngineeringXi’an 710025China

Remaining useful life(RUL) prediction is one of the most crucial elements in prognostics and health management(PHM). Aiming at the imperfect prior information, this paper proposes an RUL prediction method based on a nonlinear random coefficient regression(RCR) model with fusing failure time ***, some interesting natures of parameters estimation based on the nonlinear RCR model are given. Based on these natures,the failure time data can be fused as the prior information reasonably. Specifically, the fixed parameters are calculated by the field degradation data of the evaluated equipment and the prior information of random coefficient is estimated with fusing the failure time data of congeneric equipment. Then, the prior information of the random coefficient is updated online under the Bayesian framework, the probability density function(PDF) of the RUL with considering the limitation of the failure threshold is performed. Finally, two case studies are used for experimental verification. Compared with the traditional Bayesian method, the proposed method can effectively reduce the influence of imperfect prior information and improve the accuracy of RUL prediction.

关键词： remaining useful life(RUL)prediction imperfect prior information failure time data nonlinear random coefficient regression(RCR)model

Remaining useful life prediction of aero-engines based on random-coefficient regression model considering random failure threshold

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Journal of Systems Engineering and Electronics 2023年第2期34卷 530-542页

作者： wang fengfei TANG Shengjin LI Liang SUN Xiaoyan YU Chuanqiang SI Xiaosheng College of Missile Engineering Rocket Force University of EngineeringXi’an 710025China

Remaining useful life(RUL)prediction is one of the most crucial components in prognostics and health management(PHM)of *** paper proposes an RUL prediction method of aero-engines considering the randomness of failure ***,a random-coefficient regression(RCR)model is used to model the degradation process of ***,the RUL distribution based on fixed failure threshold is *** prior parameters of the degradation model are calculated by a two-step maximum likelihood estimation(MLE)method and the random coefficient is updated in real time under the Bayesian *** failure threshold in this paper is defined by the actual degradation process of *** that,a expectation maximization(EM)algorithm is proposed to estimate the underlying failure threshold of *** addition,the conditional probability is used to satisfy the limitation of failure ***,based on above results,an analytical expression of RUL distribution of aero-engines based on the RCR model considering random failure threshold(RFT)is derived in a ***,a case study of turbofan engine is used to demonstrate the effectiveness and superiority of the RUL prediction method and the parameters estimation method of failure threshold proposed.

关键词： aero-engine remaining useful life(RUL) random failure threshold(RFT) random-coefficient regression(RCR) parameters estimation

腹腔镜增强视野完全腹膜外疝修补术和腹腔镜腹膜内补片修补术在腹壁疝修补中的安全性及临床疗效

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中华疝和腹壁外科杂志（电子版） 2024年第3期18卷 296-301页

作者：徐杨荣杨毅王凤飞潘姣湖南省岳阳市人民医院疝和腹壁外科 414000

目的探讨腹腔镜增强视野完全腹膜外疝修补术(e-TEP)和腹腔镜腹膜内补片修补术(IPOM)在腹壁疝治疗中的应用价值,并阐述手术操作流程及技术细节,分析其可行性和有效性及经济性。方法回顾性分析2018年1月至2021年12月湖南省岳阳市人民医院8... 详细信息

目的探讨腹腔镜增强视野完全腹膜外疝修补术(e-TEP)和腹腔镜腹膜内补片修补术(IPOM)在腹壁疝治疗中的应用价值,并阐述手术操作流程及技术细节,分析其可行性和有效性及经济性。方法回顾性分析2018年1月至2021年12月湖南省岳阳市人民医院82例腹壁疝患者的临床资料,按照术式不同分为对照组(40例)和试验组(42例)。对照组给予IPOM防粘连修补术,试验组给予e-TEP(普通补片)腹壁疝修补术治疗,比较2组患者术中及术后相关临床指标,并发症发生情况,对术后生活的满意度及住院费用。结果2组患者一般资料之间差异无统计学意义(P>0.05);试验组手术时间长于对照组,术中失血量多于对照组,差异均有统计学意义(P0.05)。试验组总并发症发生率(14.30%)高于对照组(5.00%),差异有统计学意义(P0.05)。2组术后总满意率比较,差异无统计学意义(P>0.05);但试验组住院费用(1.52±0.23)万元低于对照组(2.45±0.35)万元,差异有统计学意义(P<0.05)。结论IPOM与e-TEP均是治疗成人腹壁疝的有效方法,两者相比较而言,IPOM具有手术时间短、手术出血量少、术后总并发症发生率低的优势,e-TEP具有住院费用低的优势。

关键词：腹壁疝腹腔镜疝修补术成人

The effects of spectrograph slit modes on the accuracy of stellar radial velocity measurement and atmospheric parameter estimation

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Science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1833-1839页

作者： wang fengfei ZHANG HaoTong LUO ALi BAI ZhongRui DU Bing ZHAO YongHeng National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences

Spectrograph slit is conventionally used to enhance the spectral resolution ~md manage how much light can be allowed to enter spectrograph. The narrow slit provides a higher resolution but sacrifices efficiency of spectrograph and results in a low signal to noise ratio （S/N） spectra product. We take GuoShouJing telescope as an example and carry out a series of experiments to study how its 2/3 slit mode affects the precision of stellar radial velocity measurement and atmosphere parameters estimate. By transforming the resolution and adding a Gaussian White Noise to the extremely high quality spectra from the Sloan Digital Sky Survey, we generate synthetic stellar spectra of various brightness with different S/Ns. Comparing the measurements on these noise added spectra with the original high quality ones, we summarize the influences of the 2/3 slit mode on the meas- urement accuracy of stellar radial velocity and atmospheric parameters.

关键词： slit mode resolution stellar radial velocity atmosphere parameters spectrograph

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基于双注意力机制的头影标志点检测研究

太原学院学报（自然科学版） 2024年第1期42卷 38-46页

作者：周金保武秀萍都冰丽张光华王烽飞卓广平马非太原师范学院计算机科学与技术学院山西晋中030619 山西医科大学口腔医院山西太原030001 太原学院计算机科学与技术系山西太原030032

准确可靠的头影标志点检测在口腔正畸的临床诊疗和研究中至关重要,但在实践中存在标志点定位难度大、准度低以及速度慢等问题,因此为了降低检测难度,提高临床诊断的准确性和高效性,提出了一种结合多注意力机制的检测算法CenterNetSC。... 详细信息

准确可靠的头影标志点检测在口腔正畸的临床诊疗和研究中至关重要,但在实践中存在标志点定位难度大、准度低以及速度慢等问题,因此为了降低检测难度,提高临床诊断的准确性和高效性,提出了一种结合多注意力机制的检测算法CenterNetSC。算法首先采用深度聚合网络DLA-34作为CenterNetSC的主干网络并用于特征提取;其次,通过在深度聚合网络中引入SE和CBAM两种注意力机制加强网络对卷积通道以及空间位置的全局感知;再次,在DLA-34网络之后加入可变形卷积捕捉对象的细节和局部信息;最后,模型在ISBI 2015 Grand Challenge的cephalometric X-rays两个测试集上分别实现了1.11 mm和1.37 mm的平均径向误差(MRE),以及2.0 mm定位误差范围内87.13%和77.03%的成功检测率(SDR)。较其他检测方法而言,CenterNetSC能够快速、准确地定位标志点,可以满足临床医学的需求。

关键词：口腔正畸标志点检测深度聚合网络注意力机制可变形卷积

Alloyed Pt-Sn nanoparticles on hierarchical nitrogen-doped carbon nanocages for advanced glycerol electrooxidation

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Nano Research 2024年第5期17卷 4055-4061页

作者： Jietao Jiang Liqi Zhou fengfei Xu Guanghai Chen Xiaoyu Liu Zhen Shen Lijun Yang Qiang Wu Xizhang wang Zheng Hu Key Laboratory of Mesoscopic Chemistry of MOE Jiangsu Provincial Laboratory for NanotechnologySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China National Laboratory of Solid State Microstructures Jiangsu Key Laboratory of Artificial Functional MaterialsCollege of Engineering and Applied Sciences and Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China

Glycerol is an alternative sustainable fuel for fuel cells,and efficient electrocatalyst is crucial for glycerol oxidation reaction(GOR).The promising Pt catalysts are subject to the inadequate capability of C-C bond cleavage and the susceptibility to ***,Pt-Sn alloyed nanoparticles are immobilized on hierarchical nitrogen-doped carbon nanocages(hNCNCs)by convenient ethylene glycol reduction and subsequent thermal *** optimal Pt_(3)Sn/hNCNC catalyst exhibits excellent GOR performance with a high mass activity(5.9 A·mg_(Pt)^(-1)),which is 2.7 and 5.4 times higher than that of Pt/hNCNC and commercial Pt/C,*** an enhancement can be mainly ascribed to the increased anti-poisoning and C-C bond cleavage capability due to the Pt_(3)Sn alloying effect and Sn-enriched surface,the high dispersion of Pt_(3)Sn active species due to N-participation,as well as the high accessibility of Pt_(3)Sn active species due to the three-dimensional(3D)hierarchical architecture of *** study provides an effective GOR electrocatalyst and convenient approach for catalyst preparation.

关键词： Pt_(3)Sn alloy hierarchical nitrogen-doped carbon nanocages glycerol electrooxidation anti-poisoning C-C bond cleavage

不同温度下团簇生长的Monte Carlo模拟

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计算物理 2009年第5期26卷 758-762页

作者：许晓军王凤飞浙江工业大学应用物理系浙江杭州310014 浙江长征职业技术学院浙江杭州310023

引入基底表面束缚能、最近邻粒子间的耦合能以及应力场,对粒子扩散势垒进行修正,采用Monte Carlo方法对不同温度下薄膜生长过程进行模拟研究.结果表明,当400 K≤T≤480 K,所得团簇的平均分支宽度基本保持不变,其值近似为单粒子直径.当50... 详细信息

引入基底表面束缚能、最近邻粒子间的耦合能以及应力场,对粒子扩散势垒进行修正,采用Monte Carlo方法对不同温度下薄膜生长过程进行模拟研究.结果表明,当400 K≤T≤480 K,所得团簇的平均分支宽度基本保持不变,其值近似为单粒子直径.当500 K≤T≤680 K,团簇分支宽度随着温度的升高而逐渐增大至约4个粒子.随着温度的继续升高,由于粒子较高的活跃性而无法凝聚形成大团簇,团簇包含粒子数的平均值小于2.还研究了不同温度下团簇在生长过程中的形貌演化过程以及团簇数变化规律.

关键词： Monte Carlo模拟分形薄膜