Application of point interpolation mesh-free method for magneto/electro rheological vibrations of sandwich conical panels
作者:
Dai, Zuocai;Wu, Shengbin;Habibi, Mostafa;Ali, Elhosiny
期刊:
Aerospace Science and Technology ,2023年135:108180 ISSN:1270-9638
通讯作者:
Wu, SB
作者机构:
[Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Wu, Shengbin; Wu, SB] Guizhou Univ Finance & Econ, Ctr Modern Educ Technol, Guiyang 550000, Guizhou, Peoples R China.;[Habibi, Mostafa] Duy Tan Univ, Inst Res & Dev, Da Nang 550000, Vietnam.;[Habibi, Mostafa] Duy Tan Univ, Fac Elect Elect Engn, Da Nang 550000, Vietnam.;[Habibi, Mostafa] Sharif Univ Technol, Ctr Excellence Design Robot & Automat, Dept Mech Engn, Azadi Ave,POB 11365 9567, Tehran, Iran.
通讯机构:
[Wu, SB ] G;Guizhou Univ Finance & Econ, Ctr Modern Educ Technol, Guiyang 550000, Guizhou, Peoples R China.
关键词:
Magneto-electro rheological core;Point interpolation mesh-free method;Polynomial basic function;Pre/post yield zones;Sandwich conical panel
摘要:
Magneto-rheological or electro-rheological materials, due to many possible control-based applications have acquired lots of attention. So, in the present work, as the first attempt, a point interpolation method is exploited to evaluate vibrations of the sandwich conical panel with magneto-rheological or electro-rheological core, and composite face sheets. Through the linear viscoelastic hypothesis, and in the pre/post-yield zones, the correlation of shear stress-strain for magneto-rheological fluid is applied. The equilibrium equations are governed by the principle of Hamilton in addition to the first-shear deformation (FSD) hypothesis. By satisfying the compatibility equations, the interfaces of the core along with composite face layers are simulated. Upon polynomial basic function, shape functions together with the approximate form of the displacement field are constructed. The correctness of the computational approach is certified through the analogical investigation. The results show that number of face layers, thickness, the pattern of composite layers, weight fraction, and electric/magnetic field, together with the geometry of the conical panel have an imperative impact on the system's natural frequency in addition to the loss factor index. © 2023 Elsevier Masson SAS
语种:
英文
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基于负荷尖峰特征LSTM自编码器的窃电识别方法
作者:
刘康;刘鑫;张蓬鹤;薛阳;李彬;...
期刊:
电力系统自动化 ,2023年47(2):96-104 ISSN:1000-1026
通讯作者:
Su, Sheng(eessheng@163.com)
作者机构:
[刘康; 李彬; 苏盛] Hunan Key Laboratory of Smart Grid Operation and Control, Changsha University of Science and Technology, Changsha;410114, China;[刘鑫] Marketing Service Center of State Grid Hunan Electric Power Company (Metering Center), Changsha;[张蓬鹤; 薛阳] China Electric Power Research Institute Co., Ltd., Beijing;100180, China
通讯机构:
[Su, S.] H;Hunan Key Laboratory of Smart Grid Operation and Control, China
关键词:
窃电;长短期记忆;神经网络;自编码器;用电特征;异常检测
摘要:
近年来,面向高损线路的窃电检测方法得到大面积工程应用,对降低窃电检测误报率和推动数据驱动窃电检测的工程应用起到了重要作用。但如何准确检出非高损线路的专变窃电用户,仍是亟待解决的难题。基于实践经验中部分窃电用户存在用电量异常尖峰这一特点,提出基于负荷尖峰特征长短期记忆(LSTM)自编码器的用户窃电识别方法。首先,分析典型窃电用户曲线形态,提炼了区分正常及窃电用户的用电量尖峰特征。然后,结合该特征和用户分时数据周期性规律,构建LSTM自编码模型重构输入得到拟合值,基于拟合值与真实值的均方误差设定自适应阈值,从而识别窃电嫌疑用户并提供具体预警尖峰时段。最后,应用实际专变用户用电数据进行算例分析,结果表明所提方法在准确率、命中率和误报率上均优于对比方法。
语种:
中文
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Machine learning prediction of higher heating value of biomass
作者:
Dai, Zuocai;Chen, Zhengxian;Selmi, Abdellatif;Jermsittiparsert, Kittisak* ;Denic, Nebojsa M.;...
期刊:
Biomass Conversion and Biorefinery ,2023年13(5):3659-3667 ISSN:2190-6815
通讯作者:
Jermsittiparsert, Kittisak
作者机构:
[Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Dai, Zuocai] Key Lab Energy Monitoring & Edge Comp Smart City, Yiyang 413002, Hunan, Peoples R China.;[Chen, Zhengxian] Columbia Univ, Dept Mech Engn, New York, NY 10027 USA.;[Selmi, Abdellatif] Prince Sattam Bin Abdulaziz Univ, Coll Engn, Dept Civil Engn, Al Kharj 11942, Saudi Arabia.;[Selmi, Abdellatif] Ecole Natl Ingenieurs Tunis ENIT, Civil Engn Lab, BP 37, Tunis 1002, Tunisia.
通讯机构:
[Jermsittiparsert, Kittisak] D;[Jermsittiparsert, Kittisak] H;Duy Tan Univ, Inst Res & Dev, Da Nang 550000, Vietnam.;Duy Tan Univ, Fac Humanities & Social Sci, Da Nang 550000, Vietnam.;Henan Univ Econ & Law, MBA Sch, Zhengzhou 450046, Henan, Peoples R China.
关键词:
Biomass;Higher heating value;ELM;Prediction
摘要:
Recently, biomass sources are important for energy applications. There is need for analyzing of the biomass model based on different components such as carbon, ash, and moisture content since the biomass sources are important for energy applications. In this paper, an extreme learning machine (ELM) is used to estimate efficiency. ELM was implemented for single-layer feed-forward neural network (SLFN) architectures. Because biomass modeling could be a very challenging task for conventional mathematical, it is suitable to apply machine learning models which could overcome nonlinearities of the process. The main attempt in this study was to develop a machine learning model for prediction of the higher heating values of biomass based on proximate analysis. According the prediction accuracy (coefficient of determination and root mean square error) of the higher heating value of the biomass, the inputs’ influence was determined on the higher heating value. According to the obtained results, fixed carbon has less moderate coefficient, ash has less correlation coefficient, and volatile matter has the most correlation coefficient. Therefore, the volatile matter percentage weight has the highest relevance on the higher heating value of the biomass. On the contrary, the ash has the smallest relevance on the higher heating value of the biomass based on machine learning approach. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.
语种:
英文
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Nanoscale Characterization and Impurities of Fused Silica Optical Surfaces
作者:
Dai, Zuocai;Zhou, Sha;Huang, Zhiliang;Li, Hao
期刊:
Advances in Materials Science and Engineering ,2022年2022 ISSN:1687-8434
通讯作者:
Dai, Zuocai(daizuocai@hncu.edu.cn)
作者机构:
[Huang, Zhiliang; Li, Hao; Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Huang, Zhiliang; Dai, Zuocai] Key Lab Energy Monitoring & Edge Comp Smart City H, Yiyang 413002, Hunan, Peoples R China.;[Zhou, Sha] Hunan City Univ, Yiyang 413002, Hunan, Peoples R China.
通讯机构:
[Dai, Z.] C;College of Mechanical and Electrical Engineering, Hunan City University, Hunan, Yiyang, China
摘要:
Fused silica is produced by melting high-purity silica and then rapidly cooling it. It has good physical and chemical properties, which also make it the raw material for most components in the optical industry, and is widely used in optical fiber communications, semiconductors, and aerospace. The content of SiO2 in fused silica is as high as 99.995% or more, but some impurities will still be generated during production and processing. The impurity elements of its optical curved surface can induce damage to the fused silica and adversely affect its performance, thereby affecting the performance of the fabricated element. In this paper, the impurities in the nanostructure of the fused silica optical surface are mainly analyzed, and the impurities on the surface are qualitatively and quantitatively analyzed by the characterization methods of secondary ion mass spectrometry (SIMS) and X-ray diffraction analysis, respectively. The main component type and content of impurities were measured. The experimental results have an important impact on the production and preparation of optical components using fused silica as raw materials, which can remove surface impurities in a targeted manner and better utilize the advantages of fused silica materials. © 2022 Zuocai Dai et al.
语种:
英文
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Fabrication of Hollow Needle Tips with Nanoholes by Plasma Maskless Processing and Calculation and Detection of Complex Surface Edges
作者:
Dai, Zuocai;Zhou, Sha;Yang, Tongguang;Wang, Yanpeng
期刊:
Advances in Materials Science and Engineering ,2022年2022 ISSN:1687-8434
通讯作者:
Dai, Zuocai(daizuocai@hncu.edu.cn)
作者机构:
[Wang, Yanpeng; Yang, Tongguang; Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Yang, Tongguang; Dai, Zuocai] Key Lab Energy Monitoring & Edge Comp Smart City H, Yiyang 413002, Hunan, Peoples R China.;[Zhou, Sha] Hunan City Univ, Yiyang 413002, Hunan, Peoples R China.
通讯机构:
[Dai, Z.] C;College of Mechanical and Electrical Engineering, Hunan, China
摘要:
The plasma maskless processing method combines the advantages of plasma etching and scanning probe processing, such as high etching efficiency, wide range of applicable materials, and high resolution. This method is based on the probe driving and detection of piezoelectric thin films, which enables all probes in the array to be processed completely independently, greatly improving the overall processing efficiency, and can effectively etch specific nano-scale regions of various materials. And it provides an effective solution for efficiently processing small batches of multi-variety micro-nano devices. In this study, a hollow needle tip with nanoholes was fabricated by plasma maskless processing, and use edge computing to calculate the complex surface shape of the needle tip. By establishing a plasma reactor, using the calculation method of the complex surface edge of the needle tip, and testing the stability of the processed nanotip by means of filling air pressure and power excitation in the experiment. The results show that when the breakdown voltage SF6 discharges, with the increase of air pressure, the breakdown voltage of the arrester first decreases and then increases gradually, and it is the smallest at 5 kPa and reaches the optimal 490 V, (PD) m = 0.5 Pa·m. And the Ar reaction ionization potential (15.76 eV) and excitation potential (11.53 eV, 11.72 eV) are lower than the splitting potential (≥16 eV) of SF6. As time goes on, high-energy particles are neutralized with the vessel wall, so the ion concentration is gradually smaller, sparse between 200 and 250, and increases from 100 to 300, which is close to the peak value, according to the gradual increase of the discharge voltage. The data obtained from the experimental test proves the reliability of the nanotips prepared in this study, and the properties remain stable under different breakdown voltages. Therefore, the nanohole hollow tip processed by maskless scanning plasma in this study has reached the standard of process use and has important application significance. © 2022 Zuocai Dai et al.
语种:
英文
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Natural wood-based metamaterials for highly efficient microwave absorption
作者:
Quan, Peng;Long, Chun;Zhou, Jun;He, Xia;Liu, Yuan;...
期刊:
Holzforschung ,2022年76(4):368-379 ISSN:0018-3830
通讯作者:
Li, Xianjun;Xie, Xinfeng
作者机构:
[Quan, Peng; Xie, Xinfeng] Michigan Technol Univ, Coll Forest Resources & Environm Sci, Houghton, MI 49931 USA.;[Liu, Yuan; Zhou, Jun; Long, Chun; Li, Xianjun] Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[He, Xia] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Peoples R China.;[DeVallance, David] InnoRenew CoE, Izola 6310, Slovenia.;[DeVallance, David] Univ Primorska, Fac Math Nat Sci & Informat Technol, Koper 6000, Slovenia.
通讯机构:
[Li, Xianjun] C;[Xie, Xinfeng] M;Cent South Univ Forestry & Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;Michigan Technol Univ, Coll Forest Resources & Environm Sci, Houghton, MI 49931 USA.
关键词:
metamaterials;microwave absorption;moisture content;wood
摘要:
While wood substances that contain water have shown a dielectric effect, they have never been directly proposed as a microwave absorption material to reduce artificial electromagnetic pollution. In this study, the microwave absorption efficiency of wood that contains water was investigated based on its dielectric properties in the microwave frequency range to optimize the parameters of wood unit cells, including the orientation, moisture content (MC) and thickness. Subsequently, inspired by the design concept of electromagnetic metamaterials, single-layer wood unit cells containing moisture were directly integrated into double epoxy resin layers. This procedure formed a natural wood-based metamaterial (NWM) with a simple periodic Sandwich structure without the need for further chemical modification and/or high energy consuming processes. Such design strategies allowed the NWMs to overcome the limitation of inherent dielectric properties of natural wood and present significantly enhanced microwave absorption performance, as well as different absorption behavior. NWMs at a MC ≤ 70% displayed a selective absorption mode, while NWMs at MC ≥ 85% showed a broadband absorption mode. Both absorption modes could achieve the peak absorptivity > 98%. Particularly, the NWM in the broadband absorption mode possessed an effective absorption (absorptivity > 90%) bandwidth of 9.04 GHz, which was 7.6 times that of natural wood (1.19 GHz). The NWMs performed well when irradiated by microwaves with different angles and directions. Also, the thickness of NWMs was only 7 mm, allowing easy incorporation of the materials in engineering designs. The use of sustainable materials, impressive performance, high stability, practical thickness, and the facile and cost-effective production technique demonstrated NWMs with great potential in designing green buildings. © 2021 Walter de Gruyter GmbH, Berlin/Boston.
语种:
英文
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计及需求侧储能事故备用风险与火电机组深度调峰的经济优化研究
作者:
魏文;姜飞;戴双凤;陈长青;陈磊
期刊:
电力系统保护与控制 ,2022年50(10):153-162 ISSN:1674-3415
作者机构:
[魏文; 戴双凤] School of Economics and Management, Changsha University of Science and Technology, Changsha;410076, China;School of Economics and Management, Hunan University of Science and Technology, Yueyang;414000, China;[姜飞; 陈磊] School of Electrical and Information Engineering, Changsha University of Science and Technology, Changsha
关键词:
储能;调峰;风险量化;粒子群算法
摘要:
针对电网调峰过程中需求侧储能(Energy Storage, ES)事故备用闲置时间过长,以及传统火电机组深度调峰(Depth Peak Regulation, DPR)成本较高的问题,提出了一种考虑需求侧储能事故备用风险与火电机组深度调峰的经济优化方法。首先,通过分析天气状态、负载率水平以及故障风险类型等影响因素,构建了考虑需求侧的ES风险量化模型、ES事故备用调峰经济模型。其次,结合火电机组进行深度调峰时对机组损伤及燃料需求分析,构建了考虑火电机组投油成本的深度调峰经济模型。最后,提出了一种基于需求侧风险量化的ES事故备用辅助火电机组DPR的经济优化模型,采用粒子群优化算法在修正后的IEEE30节点系统中进行算例验证。结果表明ES事故备用参与DPR能有效提高电网调峰能力和ES事故备用利用率。
语种:
中文
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Nanofabrication of Silicon Carbide and Optical Processing and Inspection of Noncurved Mirrors
作者:
Dai, Zuocai;Zhou, Sha;Yang, Tongguang;Zou, Lihong
期刊:
Advances in Materials Science and Engineering ,2022年2022 ISSN:1687-8434
通讯作者:
Dai, Zuocai(daizuocai@hncu.edu.cn)
作者机构:
[Zou, Lihong; Yang, Tongguang; Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Yang, Tongguang; Dai, Zuocai] Key Lab Energy Monitoring & Edge Comp Smart City H, Yiyang 413002, Hunan, Peoples R China.;[Zhou, Sha] Hunan City Univ, Yiyang 413002, Hunan, Peoples R China.
通讯机构:
[Dai, Z.] C;College of Mechanical and Electrical Engineering, Hunan, China
摘要:
With the gradual development of modern technology, there are still areas that need to be broken through in the field of science. In today's society, the application range of noncurved mirrors is becoming more and more extensive. The application of aspheric mirrors will not only improve the imaging quality in all aspects but also improve the application of aspheric surfaces in aerospace, military, optics, physics, etc., and enhance economic benefits. Silicon carbide materials can be used in combination with noncurved mirror materials and produced in the market. This paper mainly studies how to prepare silicon carbide nanomaterials and discusses the relevant characteristics of silicon carbide through the preparation of silicon carbide materials. The aspheric mirror is mainly based on the large-diameter, high-precision aspheric mirror manufacturing system as the research background, which provides certain work experience for the follow-up research. Through the background research of the optical system of the aspheric mirror, this paper analyzed the essentials of aspheric processing technology and then combined the related content of the silicon carbide nanometer and the aspheric mirror. Nowadays, with the development of science and technology, the development prospects of silicon carbide nanomaterials are also more and more broad. After the entire production line of silicon carbide material was put into the production line, it has been recognized by the market, and the benefits are very good, bringing great production benefits to people, and it can be produced on a large scale in the future. © 2022 Zuocai Dai et al.
语种:
英文
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Frequency characteristics and sensitivity analysis of a size-dependent laminated nanoshell
作者:
Dai, Zuocai;Jiang, Zhiyong;Zhang, Liang* ;Habibi, Mostafa
期刊:
Advances in Nano Research ,2021年10(2):175-189 ISSN:2287-237X
通讯作者:
Zhang, Liang
作者机构:
[Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Dai, Zuocai] Key Lab Energy Monitoring & Edge Comp Smart City, Yiyang 413002, Hunan, Peoples R China.;[Jiang, Zhiyong] Guilin Univ Aerosp Technol, Pract Teaching Dept, Guilin 541004, Guangxi, Peoples R China.;[Zhang, Liang] Tsinghua Univ, Sch Aerosp Engn, Beijing 100084, Peoples R China.;[Habibi, Mostafa] Duy Tan Univ, Inst Res & Dev, Da Nang 550000, Vietnam.
通讯机构:
[Zhang, Liang] T;Tsinghua Univ, Sch Aerosp Engn, Beijing 100084, Peoples R China.
关键词:
finite element method;laminated cylindrical nanoshell;sensitivity analysis;bi-directional thermal loading;FGDQM
摘要:
In this article, frequency characteristics, and sensitivity analysis of a size-dependent laminated composite cylindrical nanoshell under bi-directional thermal loading using Nonlocal Strain-stress Gradient Theory (NSGT) are presented. The governing equations of the laminated composite cylindrical nanoshell in thermal environment are developed using Hamilton's principle. The thermodynamic equations of the laminated cylindrical nanoshell are obtained using First-order Shear Deformation Theory (FSDT) and Fourier-expansion based Generalized Differential Quadrature element Method (FGDQM) is implemented to solve these equations and obtain natural frequency and critical temperature of the presented model. The novelty of the current study is to consider the effects of bi-directional temperature loading and sensitivity parameter on the critical temperature and frequency characteristics of the laminated composite nanostructure. Apart from semi-numerical solution, a finite element model was presented using the finite element package to simulate the response of the laminated cylindrical shell. The results created from finite element simulation illustrates a close agreement with the semi-numerical method results. Finally, the influences of temperature difference, ply angle, length scale and nonlocal parameters on the critical temperature, sensitivity, and frequency of the laminated composite nanostructure are investigated, in details.
语种:
英文
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计及柔性负荷的电网储能和光伏协调规划研究
作者:
陈长青;阳同光
期刊:
电力系统保护与控制 ,2021年49(4):169-177 ISSN:1674-3415
作者机构:
[陈长青; 阳同光] College of Mechanical and Electrical Engineering, Hunan City University, Yiyang;413000, China;Hunan Key Laboratory of Energy Perception and Edge Computing in Smart City, Yiyang;[陈长青; 阳同光] 413000, China<&wdkj&>Hunan Key Laboratory of Energy Perception and Edge Computing in Smart City, Yiyang;[陈长青; 阳同光] 413000, China
关键词:
柔性负荷;合同策略;削峰填谷;时序互补;光伏消纳
摘要:
具有"虚拟储能"作用的柔性负荷能够从时空上改变原有负荷分布,降低峰谷差,然而现有规划并未对其进行深入研究。为此,通过构建柔性负荷响应模型,并提出优先将高峰时段柔性负荷转移至光伏出力高峰期的合同策略,进而提高光伏利用率。其次,构建计及柔性负荷的储能和光伏协调规划模型,以便充分发挥柔性负荷"削峰填谷"及光储时序互补作用。最后,通过对10k V 37节点实际配电网进行仿真。结果表明,从经济角度分析,柔性负荷相比储能更具优势,能有效降低储能容量配置和提高光伏消纳能力。
语种:
中文
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Ablation mechanism investigation and ablation threshold prediction of single crystal diamond irradiated by femtosecond laser
作者:
Yin, Jiu;Chen, Genyu* ;Zhu, Zhichao;Jin, Mengqi;Hu, Bang
期刊:
Diamond and Related Materials ,2021年111:108173- ISSN:0925-9635
通讯作者:
Chen, Genyu
作者机构:
[Yin, Jiu; Zhu, Zhichao; Jin, Mengqi; Hu, Bang; Chen, Genyu] State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Yin, Jiu] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413000, Hunan, Peoples R China.;[Yin, Jiu; Zhu, Zhichao; Jin, Mengqi; Hu, Bang; Chen, Genyu] Hunan Univ, Laser Res Inst, Changsha 410082, Hunan, Peoples R China.
通讯机构:
[Chen, Genyu] S;State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词:
Femtosecond laser;Single crystal diamond;Free electron density;Improved TTM;Ablation threshold
摘要:
Femtosecond laser has proved to be a promising approach for single crystal diamond (SCD) processing, but the interaction mechanism between femtosecond laser and SCD is not well understood and need further theoretical investigation. In this paper, the simple rate equation was utilized to analyze the free electron excitation and evolution process and the temporal evolution of free electron density was simulated. In order to reveal the thermal interaction between electron and lattice subsystem of ablated SCD, the improved two temperature model which takes the variation of optical properties of the SCD surface caused by the excited plasma into account has been built up. The laser ablation threshold of SCD was also predicted under two theoretical models respectively. According to the single pulse ablation experiments, the simulated ablation thresholds of SCD are basically in agreement with the experimental results. © 2020 Elsevier B.V.
语种:
英文
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On the vibrations of the non-polynomial viscoelastic composite open-type shell under residual stresses
作者:
Dai, Zuocai;Zhang, Liang* ;Bolandi, Seyedeh Yasaman;Habibi, Mostafa
期刊:
Composite Structures ,2021年263:113599- ISSN:0263-8223
通讯作者:
Zhang, Liang
作者机构:
[Dai, Zuocai] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413002, Hunan, Peoples R China.;[Dai, Zuocai] Key Lab Energy Monitoring & Edge Comp Smart City, Yiyang 413002, Hunan, Peoples R China.;[Zhang, Liang] Tsinghua Univ, Sch Aerosp Engn, Beijing 100084, Peoples R China.;[Bolandi, Seyedeh Yasaman] Ferdowsi Univ Mashhad, Engn Fac, Dept Mat Sci & Engn, Mashhad, Razavi Khorasan, Iran.;[Habibi, Mostafa] Duy Tan Univ, Inst Res & Dev, Da Nang 550000, Vietnam.
通讯机构:
[Zhang, Liang] T;Tsinghua Univ, Sch Aerosp Engn, Beijing 100084, Peoples R China.
关键词:
Graphene platelets;Linear and torsional gradient elastic foundation;Multi-directional initially stresses;Sandwich open-type shell;Three-dimensional elasticity theory
摘要:
This paper presents the first attempt to investigate the mechanical behaviors of the three-dimensional theory of poroelasticity for functionally graded graphene platelets reinforced composite (FG-GPLRC) open-shell resting on a non-polynomial viscoelastic substrate involving friction force and under residual stresses. For this purpose, three parameters viscoelastic foundation is developed by taking into account the torsional interaction and horizontal friction force. The open-type shell comprises multilayers with uniformly dispersed graphene platelets (GPLs) in each fictitious layer of facing sheets. Still, its weight fraction changes layer-by-layer along the thickness direction. For solving the governing equations, the state-space based differential quadrature method is presented to determine the frequency response of the sandwich open-type shell. The influences of several parameters, such as various types of horizontal friction force, initial circumferential stress, linear and torsional gradient elastic foundation, and damping parameter, are investigated on the amplitude and frequency of the FG-GPLRC open-shell resting on a non-polynomial viscoelastic substrate. Results reveal that the poroelasticity theory has an overestimation of the frequency in comparison with 3D- elasticity. The fundamental and golden results of this paper are that by considering initial compressive stress, the system's stability increases, and the energy absorption of the structure improves. © 2021 Elsevier Ltd
语种:
英文
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Effective metal mold method for the production of bionic adhesives based on electrochemical modifications
作者:
Yuan, Cong;Ji, Keju;Tang, Yiqiang;Wang, Zizhuo;Cui, Enhua;...
期刊:
中国航空学报(英文版) ,2021年34(4):332-340 ISSN:1000-9361
通讯作者:
JI, Keju(jikeju@nuaa.edu.cn)
作者机构:
[Tang, Yiqiang; Wang, Zizhuo; Yuan, Cong; Cui, Enhua; Ji, Keju; Chen, Jian; Dai, Zhendong] Nanjing Univ Aeronaut & Astronaut, Coll Mech & Elect Engn, Jiangsu Prov Key Lab Bion Funct Mat, Nanjing 210016, Peoples R China.;[Yuan, Cong] Hunan City Univ, Coll Mech & Elect Engn, Yiyang 413000, Peoples R China.
通讯机构:
[JI, K.] J;Jiangsu Provincial Key Laboratory of Bionic Functional Materials, China
关键词:
Bionic adhesive;Dry adhesion;Electro-deposition;Metal mold;Micro/nano-imprint;Micro-porous
摘要:
Bionic adhesives with tip-expanded microstructural arrays have attracted considerable interest owing to their high adhesive performance at low preloads. Their mainstream manufacturing method is molding. Due to most molds are made of silicon or silicon-based soft templates, and have poor wear resistant or vulnerability to high temperature, limiting their use in large-scale manufacturing. Nickel is widely used as an embossing mold in the micro/nano-imprint industrial process owing to its good mechanical properties. However, the processing of metal molds for the fabrication of tip-expanded microstructural arrays is extremely challenging. In this study, using electrodeposition techniques, the shape of the micropores is modified to obtain end-controlled pores. The effect of the non-uniformity of the electric field on the microporous morphology in the electrodeposition process is systematically investigated. Furthermore, the mechanism of non-uniformity evolution of the microporous morphology is revealed. The optimized microporous metal array is used as a mold to investigate the cavity evolution laws of the elastic cushions under pre-load during the manufacturing process. As a result, typical bionic adhesives with tip-expansion are obtained. Moreover, corresponding adhesion mechanics are analyzed. The results show that electrochemical modifications have broad application prospects in the fabrication of tip-expanded microstructures, providing a new method for the large-scale fabrication of bionic adhesives based on metal molds.
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英文
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一种医用声觉报警信号输出算法及应用
作者:
袁越阳;陈宇清;孙建国;马小林
期刊:
电子科技大学学报 ,2020年49(2):235-239 ISSN:1001-0548
作者机构:
[袁越阳; 马小林] School of Mechanical and Electrical Engineering, Hunan City University, Yiyang;Hunan;413099, China;[孙建国] Suzhou Curative Medical Technical Company, Suzhou;Jiangsu
关键词:
声觉报警;音频信号;Goertzel算法;医疗电子
摘要:
为了提高对音频报警发生源的空间定位,帮助操作者迅速准确的确定报警发生位置,医疗电子设备通常要求其声觉报警具有更加丰富的泛音。但目前主要采用音频录制或脉冲信号为驱动信号的方式,容易引入噪声,从而影响报警质量。为此,将复数领域的Goertzel算法简化为实数领域,以便于编写用于嵌入式单片机的应用程序。提出了一种多泛音声觉报警信号输出的算法,并以实现500 Hz基音及其2~5次泛音的音频信号发生器为例,开发设计了基于嵌入式单片机LM3S9B92的应用程序和硬件音频驱动电路,得到了低噪声、多泛音的声觉报警信号。
语种:
中文
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Advanced solution strategies for time-dependent reliability based design optimization
作者:
Shi, Yan;Lu, Zhenzhou* ;Huang, Zhiliang;Xu, Liyang;He, Ruyang
期刊:
Computer Methods in Applied Mechanics and Engineering ,2020年364:112916- ISSN:0045-7825
通讯作者:
Lu, Zhenzhou
作者机构:
[Lu, Zhenzhou; Shi, Yan; He, Ruyang; Xu, Liyang] Northwestern Polytech Univ, Sch Aeronaut, Xian 710072, Peoples R China.;[Huang, Zhiliang] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413002, Peoples R China.
通讯机构:
[Lu, Zhenzhou] N;Northwestern Polytech Univ, Sch Aeronaut, Xian 710072, Peoples R China.
关键词:
Angle descent mean value;Minimum performance target point;Time-dependent reliability based design optimization;Time-dependent sequential optimization and reliability assessment;Time-dependent single loop approach
摘要:
Aiming at accurately and efficiently solve the Time-dependent Reliability Based Design Optimization (T-RBDO), two advanced solution strategies respectively called Time-dependent Sequential Optimization and Reliability Assessment (T-SORA) and Time-dependent Single Loop Approach (T-SLA) are established. Before constructing the T-SORA and T-SLA, a two-stage optimization is firstly established, in which the first stage makes the minimum instantaneous reliability indexes of probabilistic constraints satisfy reliability index targets and the second stage performs the time-dependent reliability indexes to match the reliability index targets. Two equivalent time-independent RBDOs are obtained based on the established two-stage optimization, and the key point is estimating the Minimum Performance Target Point (MPTP) in each stage. Two single optimization processes are constructed in T-SORA to efficiently estimate MPTPs in its two stages respectively. Two sequential single procedures are established in T-SLA to efficiently solve MPTPs and design parameter solutions in its two stages respectively, in which a new MPTP searching technique named Angle Descent Mean Value (ADMV) is proposed to approximate MPTP in each iteration. Furthermore, time-dependent reliability analysis is only required in the second stage, which will further improve the computational efficiency. Several numerical and engineering examples are introduced to show the effectiveness of the proposed T-SORA and T-SLA for solving T-RBDO. © 2020 Elsevier B.V.
语种:
英文
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Time-dependent reliability-based design optimization with probabilistic and interval uncertainties
作者:
Shi, Yan;Lu, Zhenzhou* ;Huang, Zhiliang
期刊:
Applied Mathematical Modelling ,2020年80:268-289 ISSN:0307-904X
通讯作者:
Lu, Zhenzhou
作者机构:
[Lu, Zhenzhou; Shi, Yan] Northwestern Polytech Univ, Sch Aeronaut, Xian 710072, Peoples R China.;[Huang, Zhiliang] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413002, Peoples R China.
通讯机构:
[Lu, Zhenzhou] N;Northwestern Polytech Univ, Sch Aeronaut, Xian 710072, Peoples R China.
关键词:
Minimum performance target point searching;Probabilistic and interval uncertainties;Sequential single-loop optimization;Time-dependent reliability-based design optimization;Worst case scenario
摘要:
Time-dependent reliability-based design optimization with both probabilistic and interval uncertainties is a cost-consuming problem in engineering practice which generally needs huge computational burden. In order to deal with this issue, a sequential single-loop optimization strategy is established in this work. The established sequential single-loop optimization strategy converts the original triple-loop optimization into a sequence of deterministic optimization, the estimations of time instant and interval value that corresponding to the worst case scenario, and the minimum performance target point searching. Two key points in the sequential single-loop optimization strategy guarantee the high efficiency of the proposed strategy. One is that no iterative searching step is needed to find the minimum performance target point at each iteration in the proposed sequential single-loop optimization strategy. The other is that only the correction step needs the reliability analysis to correct the design parameter solutions. In the example section, four minimum performance target point searching techniques are combined with the sequential single-loop optimization strategy to solve the corresponding optimization problems so to illustrate the effectiveness of the established strategy. © 2019 Elsevier Inc.
语种:
英文
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Reliability-based multidisciplinary design optimization using incremental shifting vector strategy and its application in electronic product design
作者:
Huang, Z. L.;Zhou, Y. S.;Jiang, C.* ;Zheng, J.;Han, X.
期刊:
力学学报:英文版 ,2018年34(2):285-302 ISSN:0567-7718
通讯作者:
Jiang, C.
作者机构:
[Huang, Z. L.] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413002, Peoples R China.;[Zhou, Y. S.; Han, X.; Huang, Z. L.; Zheng, J.; Jiang, C.] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
通讯机构:
[Jiang, C.] H;Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词:
Reliability-based design optimization (RBDO);Multidisciplinary design optimization (MDO);Incremental shifting vector (ISV);Decoupling algorithm;Electronic product
摘要:
Use of multidisciplinary analysis in reliability-based design optimization (RBDO) results in the emergence of the important method of reliability-based multidisciplinary design optimization (RBMDO). To enhance the efficiency and convergence of the overall solution process, a decoupling algorithm for RBMDO is proposed herein. Firstly, to decouple the multidisciplinary analysis using the individual disciplinary feasible (IDF) approach, the RBMDO is converted into a conventional form of RBDO. Secondly, the incremental shifting vector (ISV) strategy is adopted to decouple the nested optimization of RBDO into a sequential iteration process composed of design optimization and reliability analysis, thereby improving the efficiency significantly. Finally, the proposed RBMDO method is applied to the design of two actual electronic products: an aerial camera and a car pad. For these two applications, two RBMDO models are created, each containing several finite element models (FEMs) and relatively strong coupling between the involved disciplines. The computational results demonstrate the effectiveness of the proposed method. © 2017, The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag GmbH Germany.
语种:
英文
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Impact of road-block on peak-load of coupled traffic and energy transportation networks
作者:
Yang, Xian;Li, Yong* ;Cai, Ye;Cao, Yijia;Lee, Kwang Y.;...
期刊:
Energies ,2018年11(7) ISSN:1996-1073
通讯作者:
Li, Yong
作者机构:
[Cao, Yijia; Yang, Xian; Li, Yong] Hunan Univ, Coll Elect & Informat Engn, Changsha 410082, Hunan, Peoples R China.;[Yang, Xian] Hunan City Univ, Sch Mech & Elect Engn, Yiyang 413002, Peoples R China.;[Cai, Ye] Changsha Univ Sci Technol, Coll Elect & Informat Engn, Changsha 410114, Hunan, Peoples R China.;[Lee, Kwang Y.] Baylor Univ, Dept Elect & Comp Engn, Waco, TX 76798 USA.;[Jia, Zhijian] State Grid Yiyang Power Supply Co, State Grid, Yiyang 413000, Peoples R China.
通讯机构:
[Li, Yong] H;Hunan Univ, Coll Elect & Informat Engn, Changsha 410082, Hunan, Peoples R China.
关键词:
Coupled traffic and energy transportation networks (CTETNs);Electric vehicles (EVs);Interactions;Peak-load spot;Road-block
摘要:
With electric vehicles (EVs) pouring into infrastructure systems, coupled traffic and energy transportation networks (CTETNs) can be applied to capture the interactions between the power grids and transportation networks. However, most research has focused solely on the impacts of EV penetration on power grids or transportation networks. Therefore, a simulation model was required for the interactions between the two critical infrastructures, as one had yet to be developed. In this paper, we build a framework with four domains and propose a new method to simulate the interactions and the feedback effects among CTETNs. Considered more accurately reflecting a realistic situation, an origin-destination (OD) pair strategy, a charging strategy, and an attack strategy are modeled based on the vehicle flow and power flow. The model is able to analyze the spatial and temporal distribution characteristics of EVs, and measure the impacts on power grids and transportation networks with road-block. The IEEE 33-bus system with geographic information was used as a test system to verify the effectiveness of the model. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.
语种:
英文
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中等时间尺度下弹道明胶的线性黏弹性模型
作者:
马小林;范毓润
期刊:
高分子材料科学与工程 ,2018年34(12):95-100 ISSN:1000-7555
通讯作者:
Fan, Yurun(yurunfan@zju.edu.cn)
作者机构:
[马小林; 范毓润] State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou;310027, China;School of Mechanical and Electrical Engineering, Hunan City University, Yiyang;413002, China;[马小林] 310027, China<&wdkj&>School of Mechanical and Electrical Engineering, Hunan City University, Yiyang
通讯机构:
[Fan, Y.] S;State Key Laboratory of Fluid Power and Mechatronic Systems, Zhejiang University, Hangzhou, China
关键词:
弹道明胶;老化行为;中等时间尺度;线性黏弹性;Burgers模型;蠕变与应力松弛
摘要:
在不同时间尺度下,明胶表现出不同的黏弹性行为。应用蠕变和应力松弛模式研究质量分数为10%的弹道明胶在中等时间尺度下的线性黏弹性行为。低剪切速率下的连续加载-卸载实验显示,在常规感知的时间尺度下(~1min)弹道明胶接近完全弹性体,其线性区应变范围为0~0.25。对蠕变实验对应的中等时间尺度(>1h),选择样品老化24h作为实验起点,这时明胶结构缓慢老化带来的影响可以忽略,从而能够构建恒定参数的本构方程来描述弹道明胶的线性黏弹性行为。对1组蠕变实验结果进行分析,可确定Burgers模型的4个粘弹性参数,然后使用该组参数的模型预测另外2组蠕变实验以及应力松弛实验。结果表明Burgers模型能较好地表征弹道明胶在中等时间尺度下的线性黏弹性行为。
语种:
中文
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Discussions on non-probabilistic convex modelling for uncertain problems
作者:
Ni, B. Y.;Jiang, C.* ;Huang, Z. L.
期刊:
Applied Mathematical Modelling ,2018年59:54-85 ISSN:0307-904X
通讯作者:
Jiang, C.
作者机构:
[Ni, B. Y.; Jiang, C.] Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.;[Huang, Z. L.] Hunan City Univ, Sch Mech & Elect Engn, Yiyang City 413002, Peoples R China.
通讯机构:
[Jiang, C.] H;Hunan Univ, Coll Mech & Vehicle Engn, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Hunan, Peoples R China.
关键词:
Uncertainty analysis;Non-probabilistic convex modelling methods;Correlation analysis;Evaluation criterion
摘要:
Non-probabilistic convex model utilizes a convex set to quantify the uncertainty domain of uncertain-but-bounded parameters, which is very effective for structural uncertainty analysis with limited or poor-quality experimental data. To overcome the complexity and diversity of the formulations of current convex models, in this paper, a unified framework for construction of the non-probabilistic convex models is proposed. By introducing the correlation analysis technique, the mathematical expression of a convex model can be conveniently formulated once the correlation matrix of the uncertain parameters is created. More importantly, from the theoretic analysis level, an evaluation criterion for convex modelling methods is proposed, which can be regarded as a test standard for validity verification of subsequent newly proposed convex modelling methods. And from the practical application level, two model assessment indexes are proposed, by which the adaptabilities of different convex models to a specific uncertain problem with given experimental samples can be estimated. Four numerical examples are investigated to demonstrate the effectiveness of the present study. © 2018 Elsevier Inc.
语种:
英文
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