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Building Simulation 2024年第7期17卷 1137-1159页

作者： Zuoyu xie Junhui Fan Bin Cao Yingxin Zhu Department of Building Science School of ArchitectureTsinghua UniversityBeijingChina Key Laboratory of Eco Planning&Green Building Ministry of Education(Tsinghua University)BeijingChina

The dynamic characteristics of different airflows on micro-scales have been explored from many perspectives since the late *** the one hand,most analytical tools and research subjects in previous contributions vary significantly:some only focus on fluctuant velocity features,while others pay attention to directional *** the other hand,despite the wide variety of existing analytical methods,they are not systematically classified and *** paper aims to establish a system including state-of-the-art tools for airflow analysis and to further design a holistic toolkit named Airflow Analytical Toolkit(AAT).The AAT contains two tools,responsible for analyzing the velocity and direction characteristics of airflows,each of which is integrated with multiple analytical *** assess the performance of the developed toolkit,we further take typical natural and mechanical winds as cases to show its excellent analytical *** the help of this toolkit,the great differences in velocity and directional characteristics among different airflows are *** comparative results reveal that not only is the velocity of natural wind more fluctuating than that of mechanical wind,but its incoming flow direction is also more *** AAT,serving as a powerful and user-friendly instrument,will hopefully offer great convenience in data analysis and guidance for a deeper understanding of the dynamic characteristics of airflows,and further remedy the gap in airflow analytical tools.

关键词： airflow analysis dynamic characteristic wind velocity wind direction thermal comfort wind comfort

Study on Theory and Application of the Energy Method used for Analyzing Compressive Instability in Sheet Forming

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厦门大学学报（自然科学版） 2002年第S1期41卷 126-127页

作者： XIONG Zhi-qing 1, xie Lan-sheng 2 (1. Department of mechanical engineering, Nanjing Institute of Techno logy, Nanjing 210013, china 2. College of mechanical and electrical engineering, Nanjing university of Aer onautics and Astronautics, Nanjing 210016, china)

It is pointed out that there was serious weakness w he n using the energy method for studying compressive plastic instability in sheet forming in the past. Where applying the deduced instability strengths to relativ e engineering analysis, theoretical solutions were away from practices. Its basi c reason is that simplified process in mathematical analysis of elastic bending energy was completely applied to that of plastic bending energy. Where the cambe r expressed by function of displacement normal to a plate was approximated to re alistic deflective camber, the displacement of deflected plate to compressed dir ection was neglected. With the aid of the improved instability strengths, the pr edictions on both critical buckling dimension of blank in cup deep-drawing with out blankholder through cylindrical die or conical die and the minimum blankhold er pressure to prevent buckling under constant load are universally in agreement with both experimental results and experiential data. On the bases of above-mentioned improvement, the approximate expressions for bo th the curvature and the twist used in equation of the energy of elastic bending are also ameliorated. Thus the obtained general equations for both the energy a nd the work done by internal force in plastic bending of a plate are more precis e than before. In the analyses of plastic buckling of shell with bending moment, the effect of bending moment is considered through the work done by simulative bending for ce. The method proposed in this paper can not only simplify analyses but also ge t practical result.

关键词： sheet forming deep-drawing buckling energy me thod

Classification and spectrum optimization method of grease based on infrared spectrum

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Friction 2024年第6期12卷 1154-1164页

作者： Xin FENG Yanqiu XIA Peiyuan xie Xiaohe LI school of Energy Power and mechanical engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The infrared(IR)absorption spectral data of 63 kinds of lubricating greases containing six different types of thickeners were obtained using the IR *** Kohonen neural network algorithm was used to identify the type of the lubricating *** results show that this machine learning method can effectively eliminate the interference fringes in the IR spectrum,and complete the feature selection and dimensionality reduction of the high-dimensional spectral *** 63 kinds of greases exhibit spatial clustering under certain IR spectrum recognition spectral bands,which are linked to characteristic peaks of lubricating greases and improve the recognition accuracy of these *** model achieved recognition accuracy of 100.00%,96.08%,94.87%,100.00%,and 87.50%for polyurea grease,calcium sulfonate composite grease,aluminum(Al)-based grease,bentonite grease,and lithium-based grease,*** on the different IR absorption spectrum bands produced by each kind of lubricating grease,the three-dimensional spatial distribution map of the lubricating grease drawn also verifies the accuracy of classification while recognizing the *** paper demonstrates fast recognition speed and high accuracy,proving that the Kohonen neural network algorithm has an efficient recognition ability for identifying the types of the lubricating grease.

关键词： grease infrared(IR)spectroscopy layered Kohonen network species recognition spectrum band optimization

A Self-Adapting and Efficient Dandelion Algorithm and Its Application to Feature Selection for Credit Card Fraud Detection

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 377-390页

作者： Honghao Zhu MengChu Zhou Yu xie Aiiad Albeshri IEEE school of Computer and Information engineering Bengbu UniversityBengbu 233030China school of Information and Electronic engineering Zhejiang Gongshang UniversityHangzhou 310018China Helen and John C.Hartmann the Department of Electrical and Computer EngineeringNew Jersey Institute of TechnologyNewark NJ 07102 USA College of Information engineering Shanghai Maritime UniversityShanghai 201306China Department of Computer Science King Abdulaziz UniversityJeddah 21481Saudi Arabia

A dandelion algorithm(DA) is a recently developed intelligent optimization algorithm for function optimization problems. Many of its parameters need to be set by experience in DA,which might not be appropriate for all optimization problems. A self-adapting and efficient dandelion algorithm is proposed in this work to lower the number of DA's parameters and simplify DA's structure. Only the normal sowing operator is retained;while the other operators are discarded. An adaptive seeding radius strategy is designed for the core dandelion. The results show that the proposed algorithm achieves better performance on the standard test functions with less time consumption than its competitive peers. In addition, the proposed algorithm is applied to feature selection for credit card fraud detection(CCFD), and the results indicate that it can obtain higher classification and detection performance than the-state-of-the-art methods.

关键词： Credit card fraud detection(CCFD) dandelion algorithm(DA) feature selection normal sowing operator

Wearable multilead ECG sensing systems using on-skin stretchable and breathable dry adhesives

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Bio-Design and Manufacturing 2024年第2期7卷 167-180页

作者： Yingxi xie Longsheng Lu Wentao Wang Huan Ma school of mechanical and Automotive engineering South China University of TechnologyGuangzhou 510641China College of Automotive and mechanical engineering Changsha University of Science and TechnologyChangsha 410114China Guangdong Cardiovascular Institute Guangdong Provincial People’s HospitalGuangzhou 510080China

Electrocardiogram(ECG)monitoring is used to diagnose cardiovascular diseases,for which wearable electronics have attracted much attention due to their lightweight,comfort,and long-term *** study developed a wearablemultilead ECG sensing system with on-skin stretchable and conductive silver(Ag)-coated fiber/silicone(AgCF-S)dry *** and normal adhesion to pigskin(0.43 and 0.20 N/cm2,respectively)was optimized by the active control of fiber density and mixing ratio,resulting in close contact in the electrode–skin *** breathableAgCF-S dry electrodewas nonallergenic after continuous fit for 24 h and can be reused/cleaned(>100 times)without loss of *** AgCF encapsulated inside silicone elastomers was overlapped to construct a dynamic network under repeated stretching(10%strain)and bending(90°)deformations,enabling small intrinsic impedance(0.3,0.1 Hz)and contact impedance variation(0.7 k)in high-frequency vibration(70 Hz).All hard/soft modules of the multilead ECG system were integrated into lightweight clothing and equipped with wireless transmission for signal *** synchronous acquisition of I–III,aVR,aVL,aVF,and V4 lead data,the multilead ECG sensing system was suitable for various scenarios,such as exercise,rest,and sleep,with extremely high signal-to-noise ratios.

关键词： Multilead electrocardiogram Dry electrodes Wearable electronics Wireless transmission

STUDY ON THE CHARACTERISTICS OF AGGLOMERATION AND CYCLONE SEPARATION OF DIESEL PARTICULATE

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Chinese Journal of mechanical engineering 2001年第4期14卷 342-346页

作者： Ning Zhi, Lu Yong (school of mechanical and electrical engineering,Northern Jiaotong university) Zi Xinyun, Ouyang Minggao Liu Shuangxi, He Yongsheng (Qinghua university) (Tianjin university) 北方交通大学北京清华大学北京天津大学天津

A particulate separation system that can be used to study the characteristics of the diesel particulate agglomeration and cyclone separation is developed It includes a diesel particulate agglomerator and a cyclone separator mainly A preliminary investigation on the cyclone separation tech nology for controlling the exhaust particulate from a diesel engine is conducted The experimental results show that the diameter distribution of the diesel particulate is changed after they pass through the agglomerator,almost 30%～40% o f the particulate agglomerated from less than 1.0μm to larger than 1.0μm ,this change contributes to trap diesel particulate With this system installed on the exhaust pipe of a single cylinder engine,the particulate separation efficiency is around 40%～60% under typical engine running condition The back pressure of this system is less than 5 kPa on full load condition,much less than that of other methods of particulate filtration This technology has the possibility to open a new prospect for particulate reduction because of its simplicity,reliability and low resistance.

关键词： Diesel particulate Agglomeration Cyclone separation

Compressive and Fracture Properties of Syntactic Foam Filled with Hollow Plastic Bead(HPC)

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Journal of Wuhan university of technology(Materials Science) 2007年第3期22卷 499-501页

作者：谢文锋 school of Materials Science and engineering Wuhan University of Technology

The compressive mechanical properties of syntactic foams reinforced by hollow plastic beads were studied by the quasi-static compression test. The failure mechanism of syntactic foams was also investigated by macroscopic and microscopic observation on the fractured specimens. The experimental results show that the density of syntactic foams is still the key factor affecting their mechanical properties. The macroscopic and microscopic observation on the fractured specimens indicates that the main failure mode is the elastic-plastic collapse caused by shear.

关键词： foam hollow plastic bead epoxy resin mechanical property failure mechanism

PID Controller Parameters Tuning of Main Steam Temperature Based on Chaotic Particle Swarm Optimization

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PID Controller Parameters Tuning of Main Steam Temperature B...

Four Methods for Roundness Evaluation

2011 IEEE International Conference on Computer Science and Automation engineering(CSAE 2011)

作者： Zhou Keliang Jiangxi university of Science and technology school of mechanical and electrical engineering Gan Zhou china Qin Jieqiong Jiangxi university of Science and technology school of mechanical and electrical engineering Gan Zhou china

The main steam temperature of thermal power units is an important control parameter to the safety and economic operation of the thermal power plant, which requires its longterm deviation to remain within ±5℃. In this paper, the PID control parameters are optimized through chaotic particle swarm optimization （CPSO）. Adopting the Chaotic Ideology--logistic map to code the particles, the initial population has a good randomicity and ergodicity. Introducing the average optimal solution during the algorithm optimization process, the particles consult the search experience of the individual particle and the population to update the next generation, so that it can optimize the PID controller effectively and comprehensively. Meanwhile, the model of the main steam temperature is simulated in MATLAB respectively with Z-N tuning, genetic algorithm （GA） and chaotic particle swarm optimization （CPSO）. The simulation result shows that because of the PID controller based on CPSO, the system responds fast and has a small overshoot. The system has a good control effect.

关键词： component the main steam temperature CPSO algorithm PID control

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Four Methods for Roundness Evaluation

2010 4th International Conference on Intelligent Information technology Application (IITA2010)

作者： Wentao Sui school of mechanical engineering Shandong university of technology Zibo china Dan Zhang school of electrical & Electronic engineering Shandong university of technology Zibo china

Whether roundness error can be evaluated accurately and efficiently or not will directly influence the mechanical products performance and *** this reason,this paper introduces simple and efficient algorithms to evaluate the roundness error from the measured points using four internationally defined methods:Least Squares Circle（LSC）,Minimum Circumscribed Circle（MCC）,Maximum Inscribed Circle（MIC） and Minimum Zone Circles（MZC）.A software has been developed using Matlab to apply these algorithms on the test data.

关键词： Roundness error Optimization Minimum zone circle Minimum circumscribed circle Maximum inscribed circle

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阻尼连续可调减振器热力学特性研究

液压与气动 2024年第9期48卷 33-40页

作者：陈楠李尊谢方伟南京业恒达智能系统有限公司江苏南京210000 中国矿业大学机电工程学院江苏徐州221116

以阻尼连续可调减振器为研究对象,根据其结构特点和工作原理,对减振器的热力学特性开展了研究。建立了减振器热力学数学模型,结合减振器阻尼力和摩擦力,搭建了减振器热力学Simulink模型,进行了不同激励下的热力学仿真,并搭建实验台进行... 详细信息

以阻尼连续可调减振器为研究对象,根据其结构特点和工作原理,对减振器的热力学特性开展了研究。建立了减振器热力学数学模型,结合减振器阻尼力和摩擦力,搭建了减振器热力学Simulink模型,进行了不同激励下的热力学仿真,并搭建实验台进行了实验验证。结果表明:相同激励下,工作电流为0 A时,减振器阻尼力热衰减最明显;建立的数学模型和搭建的热力学模型均具有较高精度,且计算效率较高,可用于减振器热力学特性的研究与预测。

关键词：阻尼连续可调减振器热力学实验台