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Bayesian network learning algorithm based on unconstrained optimization and ant colony optimization

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Journal of Systems Engineering and Electronics 2012年第5期23卷 784-790页

作者： Chunfeng Wang Sanyang Liu mingmin zhu Department of Mathematical Sciences Xidian University Xi'an 710071 E R. China Department of Mathematics Henan Normal University Xinxiang 453007 E R. China

Structure learning of Bayesian networks is a wellresearched but computationally hard task.For learning Bayesian networks,this paper proposes an improved algorithm based on unconstrained optimization and ant colony optimization（U-ACO-B） to solve the drawbacks of the ant colony optimization（ACO-B）.In this algorithm,firstly,an unconstrained optimization problem is solved to obtain an undirected skeleton,and then the ACO algorithm is used to orientate the edges,thus returning the final structure.In the experimental part of the paper,we compare the performance of the proposed algorithm with ACO-B algorithm.The experimental results show that our method is effective and greatly enhance convergence speed than ACO-B algorithm.

关键词： Bayesian network structure learning ant colony optimization unconstrained optimization

Voltage control of ferromagnetic resonance

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Journal of Advanced Dielectrics 2016年第2期6卷 27-38页

作者： Ziyao Zhou Bin Peng mingmin zhu Ming Liu Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric Research Xi'an Jiaotong University Xi'an 710049P.R.China

Voltage control of magnetism in multiferroics,where the ferromagnetism and ferroelectricity are simultaneously exhibiting,is of great importance to achieve compact,fast and energy efficient voltage controllable magnetic/microwave devices.Particularly,these devices are widely used in radar,aircraft,cell phones and satellites,where volume,response time and energy consumption is critical.Researchers realized electric field tuning of magnetic properties like magnetization,magnetic anisotropy and permeability in varied multiferroic heterostructures such as bulk,thin films and nanostructure by different magnetoelectric(ME)coupling mechanism:strain/stress,interfacial charge,spin–electromagnetic(EM)coupling and exchange coupling,etc.In this review,we focus on voltage control of ferromagnetic resonance(FMR)in multiferroics.ME coupling-induced FMR change is critical in microwave devices,where the electric field tuning of magnetic effective anisotropic field determines the tunability of the performance of microwave devices.Experimentally,FMR measurement technique is also an important method to determine the small effective magnetic field change in small amount of magnetic material precisely due to its high sensitivity and to reveal the deep science of multiferroics,especially,voltage control of magnetism in novel mechanisms like interfacial charge,spin–EM coupling and exchange coupling.

关键词： Multiferroics magnetoelectric coupling ferromagnetic resonance voltage control thin films

基于YOLOv5s的轻量级茶叶嫩芽终端检测模型

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浙江农业学报 2024年第6期36卷 1413-1424页

作者：朱铭敏张国平谭建军孙玲姣朱黎焦洁华中师范大学物理科学与技术学院湖北武汉430079 湖北恩施学院智能工程学院湖北恩施445000 湖北民族大学智能科学与工程学院湖北恩施445000

在茶园环境中快速精准识别茶叶嫩芽是实现智能化采茶的关键技术之一,但茶芽检测模型的复杂性导致模型参数量大、计算量大、模型尺寸大,限制了模型在采茶机器人嵌入式设备的部署。鉴于此,本文提出一种基于YOLOv5s的轻量级茶叶嫩芽终端检... 详细信息

在茶园环境中快速精准识别茶叶嫩芽是实现智能化采茶的关键技术之一,但茶芽检测模型的复杂性导致模型参数量大、计算量大、模型尺寸大,限制了模型在采茶机器人嵌入式设备的部署。鉴于此,本文提出一种基于YOLOv5s的轻量级茶叶嫩芽终端检测模型。首先,使用轻量级网络GhostNet替换YOLOv5s中的Backbone网络,并重构Neck网络,降低模型的参数量、计算量和内存占用量,改进后的模型分别降低了47.64%、49.36%、45.51%。其次,通过引入协调注意力(coordinate attention,CA)机制,抑制图像背景信息,增强模型对茶叶嫩芽的特征提取能力。接着,在Neck网络引入多尺度特征融合(multi-scale context,MSC)模块,有效融合浅层图像特征和深层语义特征,帮助网络模型提取有效识别信息。最后,使用边界框回归损失函数EIOU替换CIOU,加快损失函数收敛速度,提高茶叶嫩芽边界框定位精度。试验结果表明,与原YOLOv5s模型相比,改进模型的参数量、计算量以及模型内存占用量分别降低了3 Mb、7.3 Gb和6.37 Mb,检测精度提升0.3%。通过模型转换将该模型移植到树莓派平台,经过环境部署和推理引擎加速,达到了轻量级模型在资源和算力有限的树莓派上对茶叶嫩芽检测的目的,在一定程度上提高了茶叶嫩芽的识别精确度,为茶叶嫩芽的智能化采摘提供了理论研究和技术支持。

关键词：茶叶嫩芽检测树莓派轻量级注意力机制

Structural and magnetic properties of La_(0.7)Sr_(0.3)MnO_(3) ferromagnetic thin film grown on PMN-PT by sol-gel method

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Journal of Advanced Dielectrics 2017年第4期7卷 47-50页

作者： Jing Zhang Peng Shi mingmin zhu Ming Liu Wei Ren Zuoguang Ye Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education and International Center for Dielectric Research Xi'an Jiaotong University Xi'an 710049P.R.China Department of Chemistry and 4D LABS Simon Fraser University BurnabyBC V5A 1S6Canada

We report the preparation of epitaxial La_(0.7)Sr_(0.3)MnO_(3) thin films grown on(001)-oriented 0.72Pb(Mg_(1/3)Nb_(2/3))TO_(3)-0.28PbTiO_(3) substrates by the sol–gel technique.The phase structure,magnetic properties and magnetoresistance of the samples are investigated by using high solution X-ray diffraction,atomic force microscopy,physical property measurement system,respectively.The La_(0.7)Sr_(0.3)MnO_(3) thin films display a well-defined hysteresis loop and typical ferromagnetism behavior at lower temperature.High magnetoresistance at 5 T of 42%appears at 227K for La_(0.7)Sr_(0.3)MnO_(3) thin film.

关键词： La_(0.7)Sr_(0.3)MnO_(3)thin films PMN-PT sol-gel method magnetoresistance

不同种植密度对青贮玉米生长、产量及经济效益的影响

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中国饲料 2024年第4期 93-96页

作者：刘兴成张建全胡健泰钟辉丽朱明敏于栋武威市农业技术推广中心甘肃武威733000 兰州大学草地农业科技学院甘肃兰州730020

文章旨在研究不同种植密度对青贮玉米生长、产量及经济效益的影响,为青贮玉米推广种植提供数据参考。青贮玉米品种选择适宜甘肃本地种植的陇青贮2号,在相同水肥管理条件下,分别设置低(6.75×10^(4)株/hm^(2))、中(7.50×10^(4)株/hm^(2)... 详细信息

文章旨在研究不同种植密度对青贮玉米生长、产量及经济效益的影响,为青贮玉米推广种植提供数据参考。青贮玉米品种选择适宜甘肃本地种植的陇青贮2号,在相同水肥管理条件下,分别设置低(6.75×10^(4)株/hm^(2))、中(7.50×10^(4)株/hm^(2))、高(8.25×10^(4)株/hm^(2))3个种植密度组,以小区测样方式,统计青贮玉米(乳熟后期至蜡熟前期)的生长、产量及经济效益情况。结果表明:(1)随着种植密度的提高,青贮玉米平均株高和平均叶片数呈下降趋势(P0.05)。(3)在经济效益方面,低、中、高种植密度组青贮玉米毛利分别为51898.77、56723.45、56497.11元/hm^(2)。结论:综合对比各项指标,陇青贮2号青贮玉米适宜种植密度为7.50×10^(4)株/hm^(2)。

关键词：种植密度青贮玉米生长性状产量经济效益

Steady-State Cornering Properties of a Non-pneumatic Tire with Mechanical Elastic Structure

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第5期34卷 586-592页

作者： Fu Hongxun Zhao Youqun Lin Fen Du Xianbin zhu mingmin College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

Mechanical elastic wheel(ME-wheel)is a new type of non-inflatable safety tyre,and the structure is significantly different from traditional pneumatic tyre.In order to investigate cornering properties of ME-wheel,experimental research on mechanics characteristics of ME-wheel under steady-state cornering conditions are carried out.The test of steady-state cornering properties of ME-wheel at different experimental parameter conditions is conducted by test bench for dynamic mechanical properties of tyre.Cornering property curves are used to analyze the steady-state cornering properties of ME-wheel,namely the variation tendency of lateral force or aligning torque with the increase of side-slip angle.Moreover,evaluation indexes for cornering properties of ME-wheel are extracted and the effect of different experimental parameters(including vertical load,friction coefficient,and speed)on cornering properties of ME-wheel is contrastively analyzed.The proposed research can provide certain reference to facilitate structure parameters and cornering properties optimizing process of ME-wheel.

关键词： tyres non-pneumatic tyre mechanical elastic structure steady-state cornering properties

Acupuncture stimulation of Yamen(GV 15), Fengfu(GV 16), Baihui(GV 20), Shuigou(GV 26) and Hegu(LI 4) reduces brain microglia activation in a traumatic brain injury rat model

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Journal of Traditional Chinese Medicine 2020年第2期40卷 267-274页

作者： Lin Shujun zhu mingmin Chen Weihao Zhang Yujuan Lin Jihuan Pu Liu Chen Shulian Zhang Yimin Liu Xin College of Chinese Medicine Jinan UniversityGuangzhou 510632China

OBJECTIVE: To evaluate the effect of acupuncture on neuroinflammation in traumatic brain injury(TBI) rats by stimulating Yamen(GV 15), Fengfu(GV16), Baihui(GV 20), Shuigou(GV 26) and Hegu(LI 4)acupoints and to investigate the mechanism underpinning this effect.METHODS: A TBI model was induced in SpragueDawley rats using Feeney's freefall impact method.Acupuncture to stimulate the Yamen(GV 15), Fengfu(GV 16), Baihui(GV 20), Shuigou(GV 26) and Hegu(LI 4) acupoints was performed on the TBI rats. After 3 consecutive days of acupuncture treatment, we investigated signal molecules, receptors and microglia related to neuroinflammation in brain tissue of the TBI rats and analyzed the possi-ble mechanism underlying the effect of acupuncture on neuroinflammation.RESULTS: After the acupuncture treatment, ionized calcium binding adaptor molecule 1(Iba1), a protein specific to microglia, was investigated. In the cortical layer of damaged brain tissue in TBI rats,the Iba1-positive area was 3.3% ± 0.9% in the rats that received acupuncture compared with 5.2% ±1.4% in the TBI rats that did not receive acupuncture, and the microglia were smaller with more slender protrusions in the acupuncture-treated rats.This result indicates that acupuncture can significantly reduce microglia activation in TBI rats. A possible mechanism for this effect is that acupuncture reduces the expression of autotaxin and lysophosphatidic acid. Together, these constitute the autotaxin-lysophosphatidic acid axis, which induces microglial activation in the brains of TBI rats. Acupuncture treatment may downregulate the expression of Lysophosphatidic acid(LPA) receptor(LPAR) 1 and LPAR2 on the microglial cytomembrane, which affects the microglia activation process.CONCLUSION: Acupuncture stimulating the Yamen(GV 15), Fengfu(GV 16), Baihui(GV 20),Shuigou(GV 26) and Hegu(LI 4) acupoints can effectively inhibit the development of neuroinflammation after TBI. One possible mechanism for this effect is that acupuncture downregulates LPA synthesis and affects the L

关键词： Acupuncture Brain injuries,traumatic Microglia Lysophospholipids Receptors,lysophosphatidic acid Neuroinflammation

Effect of Moving Endwall on Hub Leakage Flow of Cantilevered Stator in a Linear Compressor Cascade

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Journal of Shanghai Jiaotong university(Science) 2022年第6期27卷 780-789页

作者：郑标颉马宇晨滕金芳居振州朱铭敏 School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

The cantilevered stator has the advantages of reducing mass and axial length of highly loaded com-pressor.The details of the hub leakage flow resulting from the clearance between the high-speed moving hub and the cantilevered stator hub are unclear.In this paper,the effect of a moving endwall on the hub leakage flow of a cantilevered stator in a linear compressor cascade was studied.After the simulation method was verified with the experimental results,the time-averaged results of unsteady Reynolds averaged Navier-Stokes(URANS)were selected to study a case with a hub clearance of 2 mm.The results show that the effect of the moving endwall of the cantilevered cascade on the general characteristics with below 30%span increases the leakage mass flow rate and reduces the static pressure coefficient at three conditions of 0°,6°,and-7°incidences,and the change is most significant at-7°incidence.The effect of the moving endwall on the total pressure loss coefficient varies with different operating conditions,which decreases by 15.94%at 0°incidence,and increases by 4.77%and 18.51%at 6°incidence and-7°incidence,respectively.The influence of the moving endwall is below 14%span at-7°incidence,below 23%span at 0°incidence,and below 30%span at 6°incidence.These effects correspond to the static pressure coefficient and the difference of static pressure coefficient representing the blade loading.In designing the cantilevered stator and matching between the stages of a multistage compressor,the quantitative research results of this paper have certain guiding significance.

关键词： compressor cantilevered stator moving endwall aerodynamic performance hub leakage flow

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信息疫情中真假信息竞争性传播研究

现代情报 2023年第9期43卷 124-136页

作者：王世雄朱明旻骆彦余浙江理工大学经济管理学院浙江杭州310018

[目的/意义]信息疫情传播的实质是真假信息竞争性传播的过程,厘清信息疫情中真假信息竞争性传播机理,对信息疫情管控策略的制定具有重要意义。[方法/过程]基于流行病模型结合用户创作行为特性构建了FT-SIR模型,求解所构建动力学模型的... 详细信息

[目的/意义]信息疫情传播的实质是真假信息竞争性传播的过程,厘清信息疫情中真假信息竞争性传播机理,对信息疫情管控策略的制定具有重要意义。[方法/过程]基于流行病模型结合用户创作行为特性构建了FT-SIR模型,求解所构建动力学模型的平衡点并进行稳定性分析,利用NetLogo模拟真假信息竞争性传播过程,同时针对微博的典型案例数据验证模型的有效性。[结果/结论]实验表明,在用户创作行为的作用下,单一信息在传播过程中会发生变异并催生真假信息的竞争性传播;“信息茧房”效应及意见领袖的存在使得用户具有不同的角色特质,进而对真假信息的竞争性传播产生显著影响。为政府采取措施降低信息疫情的危害提供了具体的管控策略与建议。

关键词：信息疫情竞争性传播信息茧房多主体建模 FT-SIR模型