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The Combined Effect of Spin-Transfer Torque and Voltage-Controlled Strain Gradient on Magnetic Domain-Wall Dynamics:Toward Tunable Spintronic Neuron

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Chinese Physics Letters 2024年第5期41卷 120-137页

作者：郁国良何鑫岩施胜宾邱阳朱明敏王嘉维李燕李元勋王杰周浩淼 College of Information Engineering China Jiliang UniversityHangzhou 310018China The Key Laboratory of Electromagnetic Wave Information Technology and Metrology of Zhejiang Province Hangzhou 310018China Department of Engineering Mechanics Zhejiang UniversityHangzhou 310027China School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

Magnetic domain wall(DW), as one of the promising information carriers in spintronic devices, have been widely investigated owing to its nonlinear dynamics and tunable properties. Here, we theoretically and numerically demonstrate the DW dynamics driven by the synergistic interaction between current-induced spin-transfer torque(STT) and voltage-controlled strain gradient(VCSG) in multiferroic heterostructures. Through electromechanical and micromagnetic simulations, we show that a desirable strain gradient can be created and it further modulates the equilibrium position and velocity of the current-driven DW motion. Meanwhile, an analytical Thiele's model is developed to describe the steady motion of DW and the analytical results are quite consistent with the simulation data. Finally, we find that this combination effect can be leveraged to design DW-based biological neurons where the synergistic interaction between STT and VCSG-driven DW motion as integrating and leaking motivates mimicking leaky-integrate-and-fire(LIF) and self-reset function. Importantly, the firing response of the LIF neuron can be efficiently modulated, facilitating the exploration of tunable activation function generators, which can further help improve the computational capability of the neuromorphic system.

关键词： tunable synergistic integrating

Global Dynamic Characteristic of Nonlinear Torsional Vibration System under Harmonically Excitation

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 132-139页

作者： shi Peiming LIU bin HOU Dongxiao Institute of Electrical Engineering Yanshan University Qinhuangdao 066004 China

Torsional vibration generally causes serious instability and damage problems in many rotating machinery parts. The global dynamic characteristic of nonlinear torsional vibration system with nonlinear rigidity and nonlinear friction force is investigated. On the basis of the generalized dissipation Lagrange＇s equation, the dynamics equation of nonlinear torsional vibration system is deduced. The bifurcation and chaotic motion in the system subjected to an external harmonic excitation is studied by theoretical analysis and numerical simulation. The stability of unperturbed system is analyzed by using the stability theory of equilibrium positions of Hamiltonian systems. The criterion of existence of chaos phenomena under a periodic perturbation is given by means of Melnikov＇s method. It is shown that the existence of homoclinic and heteroclinic orbits in the unperturbed system implies chaos arising from breaking of homoclinic or heteroclinic orbits under perturbation. The validity of the result is checked numerically. Periodic doubling bifurcation route to chaos, quasi-periodic route to chaos, intermittency route to chaos are found to occur due to the amplitude varying in some range. The evolution of system dynamic responses is demonstrated in detail by Poincare maps and bifurcation diagrams when the system undergoes a sequence of periodic doubling or quasi-periodic bifurcations to chaos. The conclusion can provide reference for deeply researching the dynamic behavior of mechanical drive systems.

关键词： nonlinear torsional vibration dynamics behavior bifurcation chaos Melnikov's method

Optimization of a crude distillation unit using a combination of wavelet neural network and line-up competition algorithm

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Chinese Journal of Chemical Engineering 2017年第8期25卷 1013-1021页

作者： bin shi Xu Yang Liexiang Yan Department of Chemical Engineering Wuhan University of Technology

The modeling and optimization of an industrial-scale crude distillation unit （CDU） are addressed. The main spec- ifications and base conditions of CDU are taken from a crude oil refinery in Wuhan, China. For modeling of a com- plicated CDU, an improved wavelet neural network （WNN） is presented to model the complicated CDU, in which novel parametric updating laws are developed to precisely capture the characteristics of CDU. To address CDU in an economically optimal manner, an economic optimization algorithm under prescribed constraints is presented. By using a combination of WNN-based optimization model and line-up competition algorithm （LCA）, the supe- rior performance of the proposed approach is verified. Compared with the base operating condition, it is validat- ed that the increments of products including kerosene and diesel are up to 20% at least by increasing less than 5% duties of intermediate coolers such as second pump-around （PA2） and third Dump-around （PA3）.

关键词： Crude oil distillation Wavelet neural network Line-up competition algorithm Optimization

Numerical analysis of role of melting rate on electroslag remelting continuous directional solidification of a die steel

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Journal of Iron and Steel Research International 2021年第12期28卷 1617-1624页

作者： Jie Zhang Jing Li Cheng-bin shi State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

The effect of melting rate on the temperature distribution,velocity field,macrosegregation and dendrite arm spacing during electroslag remelting continuous directional solidification process with a mould of 160 mm in diameter was *** mechanism of solute transport and dendrite growth of austenitic hot-work die steel during electroslag remelting process was *** results showed that a lower melting rate contributed to a higher temperature gradient as well as a shallower liquid metal molten *** the increase in the melting rate,the central counterclockwise vortex in the slag and clockwise vortex in the liquid metal molten pool grew,whereas the marginal clockwise vortex in the slag *** increasing melting rate,the macrosegregation of carbon became more serious,whereas the average value of secondary dendrite arm spacing first decreased and then *** secondary dendrite arm spacing reached a minimum value at melting rate of 98 kg/h,which indicated that 98 kg/h was a proper melting rate for electroslag remelting continuous directional solidification process with a mould of 160 mm in diameter.

关键词： Electroslag remelting continuous directional solidification Melting rate Numerical simulation Solidification structure Die steel

房建工程项目质量成本控制策略研究——基于系统动力学模型

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重庆建筑 2024年第5期23卷 32-36,39页

作者：施彬钱峰薛连成都建工第九建筑工程有限公司四川成都610031

为改进房建工程项目的质量经济性,应在符合质量标准的前提下,选择低质量成本控制策略。该文根据工程质量形成的过程和质量成本模型建立工程质量投入策略分析流量图,使用Vensim软件构建了系统动力学模型,通过改变各项质量投入比例,观察... 详细信息

为改进房建工程项目的质量经济性,应在符合质量标准的前提下,选择低质量成本控制策略。该文根据工程质量形成的过程和质量成本模型建立工程质量投入策略分析流量图,使用Vensim软件构建了系统动力学模型,通过改变各项质量投入比例,观察相应成本的变化规律。结论表明,在成品质量较低的情况下,成品保护投入的意义不大;在成品质量水平达到要求的情况下,成品保护投入也需维持在合理的区间。研究同时提出了各项质量投入的参考比例,可为施工企业精细化管理提供参考。

关键词：质量经济性成本控制系统动力学质量成本 Vensim

上前牙区改良数字化印模复制穿龈轮廓的临床研究

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中华口腔医学研究杂志（电子版） 2024年第2期18卷 103-110页

作者：梁亮鄢雷施斌东莞健力口腔医院种植科东莞523000

目的对比研究改良数字化印模与传统个性化印模在上前牙区种植美学修复中复制穿龈轮廓的临床效果。方法选取2021年3-12月在东莞健力口腔医院已行美学区种植,需要继续行美学修复的患者,进行前瞻性临床研究。经种植临时冠获得理想的软组织... 详细信息

目的对比研究改良数字化印模与传统个性化印模在上前牙区种植美学修复中复制穿龈轮廓的临床效果。方法选取2021年3-12月在东莞健力口腔医院已行美学区种植,需要继续行美学修复的患者,进行前瞻性临床研究。经种植临时冠获得理想的软组织塑形后,采取随机数抽签确定印模方法。改良数字化印模为试验组(数字化组),传统聚醚橡胶个性化印模为对照组(聚醚橡胶组)。主要评价指标为穿龈轮廓复制精确度,次要评价指标为印模时间、咬合及邻接精确度、患者VAS印模舒适度。采用两样本的t检验分析穿龈轮廓精确度(软件分析)、印模时间及舒适度的组间差异;采用Wilcoxon秩和检验分析咬合、邻接及穿龈轮廓精确度(主观评价)的组间差异。结果每组纳入病例20例,共40例。数字化组穿龈形态误差为(0.39±0.09)mm,明显小于聚醚橡胶组(0.60±0.09)mm,差异有统计学意义(t=-7.525,P<0.001);数字化组平均印模时间(19.5±3.1)min,明显少于聚醚橡胶组(39.3±6.1)min,差异有统计学意义(t=-13.017,P<0.001)。数字化组的咬合精确度(Z=-1.025,P=0.305)及邻接精确度(Z=-1.233,P=0.218)与聚醚橡胶组差异均无统计学意义,在穿龈轮廓复制精确度方面明显优于聚醚橡胶组,差异有统计学意义(Z=-4.684,P<0.001);VAS得分数字化组(2.45±1.10)显著低于聚醚橡胶组(7.00±1.45),差异有统计学意义(t=11.179,P<0.001)。结论前牙美学区改良数字化印模技术与传统个性化印模技术两种方法的临床结果均较好,数字化印模技术在临床效率、精确性及舒适性上更具优势。

关键词：口腔美学牙种植体数字化印模穿龈轮廓

基于改进U-Net的多流视网膜血管分割算法

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计算机系统应用 2024年第7期33卷 129-138页

作者：陆锡恒宣士斌广西民族大学人工智能学院南宁530006 广西混杂计算与集成电路设计分析重点实验室南宁530006

针对传统U型网络特征冗余以及视网膜血管形态复杂、细血管分割困难等问题,提出一种基于改进U-Net的多流视网膜血管分割算法.算法包含两种特征流向,分别是全局分割流与边缘特化流.为了减少特征冗余,全局分割流在部分卷积的基础上采用快... 详细信息

针对传统U型网络特征冗余以及视网膜血管形态复杂、细血管分割困难等问题,提出一种基于改进U-Net的多流视网膜血管分割算法.算法包含两种特征流向,分别是全局分割流与边缘特化流.为了减少特征冗余,全局分割流在部分卷积的基础上采用快速提取模块替代传统的U-Net卷积块,构建了能够高效提取血管特征、加快算法推理速度的改进U-Net模型;为了减少噪声干扰、提升细血管的分割精度,边缘特化流利用形态学生成的边缘标注信息为指导,采用多个边缘提取模块,结合全局分割流的高级语义特征以及边缘注意力,更具针对性的提取血管细节信息,增强细血管的特征表达.在DRIVE与STARE数据集上进行了算法的有效性测试,敏感度分别为0.8415和0.8369,准确率分别为0.9701和0.9718,AUC值分别为0.9877和0.9909,整体性能优于现有算法.

关键词： U-Net 全局分割流部分卷积边缘特化流边缘注意力

水性汽车修补漆闪光金属底色漆中铝粉定向的探讨

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现代涂料与涂装 2024年第8期27卷 19-24页

作者：马继亮施锦斌巴斯夫新材料有限公司

基于实践经验，从配方和应用角度阐述了汽车修补漆领域的水性铝粉漆的颜料定向机理、影响铝粉定向排列的各种可能因素，包括从原料选择、搭配，配方设计、优化，再到施工应用条件的设定、控制等一系列完整的过程。并以通俗的术语和实用... 详细信息

基于实践经验，从配方和应用角度阐述了汽车修补漆领域的水性铝粉漆的颜料定向机理、影响铝粉定向排列的各种可能因素，包括从原料选择、搭配，配方设计、优化，再到施工应用条件的设定、控制等一系列完整的过程。并以通俗的术语和实用的方式对其进行梳理和总结，为开发水性金属铝粉漆配方特别是水性汽车修补铝粉底色漆提供一些可能的方向和建议，同时也可以作为水性珠光漆的参考。

关键词：汽车修补漆水性铝粉底色漆铝粉定向

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MiT家族易位性肾癌影像诊断与鉴别诊断

临床放射学杂志 2024年第3期43卷 402-409页

作者：赵娜史彬陈东宋德梅曹锋高飞董江宁中国科学技术大学附属第一医院西区安徽省肿瘤医院影像科合肥230031

目的探讨MiT家族易位性肾细胞癌(MiT RCC)的影像表现及与肾透明细胞癌(CCRCC)及乳头状肾细胞癌(PRCC)的鉴别诊断价值。方法选择经手术病理证实的11例MiT RCC患者CT及MRI影像资料,分析患者的性别及年龄、病灶大小、形态、出血、假包膜... 详细信息

目的探讨MiT家族易位性肾细胞癌(MiT RCC)的影像表现及与肾透明细胞癌(CCRCC)及乳头状肾细胞癌(PRCC)的鉴别诊断价值。方法选择经手术病理证实的11例MiT RCC患者CT及MRI影像资料,分析患者的性别及年龄、病灶大小、形态、出血、假包膜、强化模式、生长方式以及对周围组织侵犯等影像学特征,并与11例CCRCC、11例PRCC的影像特点对照分析。结果 11例MiT RCC患者中男3例,女8例,年龄10~73岁,平均(33.18±17.41)岁。11例MiT RCC与11例CCRCC和11例PRCC 3组间分析结果显示:患者年龄、性别、肿块位置、有无假包膜、有无出血、发病年龄分布、强化程度组间差异具有统计学意义(P0.05)。MiT RCC相比CCRCC、PRCC发病年龄更小,女性更多见,出血发生率更高,更易表现为肾髓内生长,假包膜MiT RCC及CCRCC发生率均较高,明显高于PRCC(PMiT RCC>PRCC(P<0.01)。结论 MiT RCC的影像学表现有一定特征性,结合好发于30岁以下的儿童及年轻人、出现肾轮廓内肿块伴出血、钙化、假包膜、多发淋巴结及远处转移,有助于提高术前诊断率。

关键词： MiT家族易位肾细胞癌肾透明细胞癌乳头状肾细胞癌计算机体层摄影术磁共振成像