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Optimization method for dynamics of non-holonomic system based on Gauss’ principle

Acta Mechanica Sinica 2020年第5期36卷 1133-1141,I0004页

作者： Wenli Yao Liusong Yang Kewei Song haiming wang Qingdao Key Laboratory for Geomechanics and Offshore Underground Engineering School of ScienceQingdao University of TechnologyQingdao 266520China College of Pipeline and Civil Engineering China University of Petroleum(East China)Qingdao 266580China

The real-time control of the non-holonomic wheel robot has put forward higher requirements for the accuracy and speed of dynamical simulation,so it is necessary to study the new dynamic modeling and calculation methods adapting to modern information *** from the traditional method solving differential-algebraic equation,the objective is to establish optimization model and effective calculating scheme for dynamics of non-holonomic system based on basic dynamical *** optimization model cannot be obtained directly from the traditional Gauss'*** using Gauss'principle of variational form,this paper deduces the minimum principle in the form of generalized coordinates and quasi-coordinates,respectively,thus allowing dynamical problems of non-holonomic systems to be incorporated into the framework of solving constrained or unconstrained optimization ***,we study a numerical calculation scheme that uses an optimization algorithm for the second form of the above optimization *** an example,the dynamical problem of a differential-driven wheeled mobile-robot system is *** optimization dynamic model of a non-holonomic robot system and the calculation model of the optimization algorithm are *** theresults of the optimization calculation with the differential-algebraic equations commonly used in dynamical problem for non-holonomic system reveals that the method in this paper is superior in terms of calculation speed and can more effectively handle constraint violations without extra constraint revision needed.

关键词： Gauss'principle Non-holonomic systems-Optimization Quasi-coordinates

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Machine-Learning-Assisted Optimization and Its Application to Antenna Designs: Opportunities and Challenges

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China Communications 2020年第4期17卷 152-164页

作者： Qi Wu Yi Cao haiming wang Wei Hong State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 211111China Purple Mountain Laboratories Nanjing 211111China

With the rapid development of modern wireless communications and radar, antennas and arrays are becoming more complex, therein having, e.g., more degrees of design freedom, integration and fabrication constraints and design objectives. While fullwave electromagnetic simulation can be very accurate and therefore essential to the design process, it is also very time consuming, which leads to many challenges for antenna design, optimization and sensitivity analysis(SA). Recently, machine-learning-assisted optimization(MLAO) has been widely introduced to accelerate the design process of antennas and arrays. Machine learning(ML) methods, including Gaussian process regression, support vector machine(SVM) and artificial neural networks(ANNs), have been applied to build surrogate models of antennas to achieve fast response prediction. With the help of these ML methods, various MLAO algorithms have been proposed for different applications. A comprehensive survey of recent advances in ML methods for antenna modeling is first presented. Then, algorithms for ML-assisted antenna design, including optimization and SA, are reviewed. Finally, some challenges facing future MLAO for antenna design are discussed.

关键词： Antenna designs machine learning optimization sensitivity analysis surrogate models

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Observed oceanic feedback to the atmosphere over the Kuroshio Extension during spring time and its possible mechanism

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Chinese Science Bulletin 2008年第12期53卷 1905-1912页

作者： XU haiming wang LinWei HE JinHai Jiangsu Key Laboratory of Meteorological Disaster and College of Atmospheric Sciences Nanjing University of Information Scienceand Technology Nanjing 210044 China

High-resolution satellite measurements are used to study the air-sea interaction over the Kuroshio Extension (KE) region during spring time. There are two oceanic fronts in the KE region off the east coast of Japan. These fronts are generally associated with strong ocean currents, which may display unstable meander, resulting in remarkable warm sea surface temperature (SST) ridges and cold SST troughs. Analyses of these satellite observations reveal a significantly positive correlation between sea surface wind speed and its underlying SST along these fronts. This positive SST-wind correlation be-comes even more significant when strong meanders occur along the fronts. This positive SST-wind correlation indicates an ocean-to-atmosphere feedback over the KE region during spring time. A high-resolution regional atmospheric model is used to investigate the atmospheric response to SST changes along the two fronts.

关键词：大气圈黑潮海洋春季

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The frontier of microplastics and nanoplastics: Soil health and carbon neutrality

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Pedosphere 2023年第1期33卷 11-13页

作者： Zhuanxi LUO Aoze LI haiming wang Baoshan XING College of Chemical Engineering Huaqiao UniversityXiamen 361021China Stockbridge School of Agriculture University of MassachusettsAmherst MA 01003USA

Microplastics and nanoplastics(MNPs)in soil have drawn increasing concerns about their potential threats to soil ecosystems due to their ubiquitous occurrence and *** interactions of MNPs with soil components,microbial community,plants,and fauna determine their impacts on soil biogeochemical processes and food ***,they are not largely *** research is also needed to develop reliable and standardized techniques and methods to characterize the relevant MNPs interacting with different types of soil ecosystems and to deeply examine their impacts on soil health,food security,and climate *** addition,mitigation protocols and regulation guidelines need to be *** findings will provide scientific and technological support for the understanding and management of soil health and carbon neutrality as influenced by MNPs.

关键词： soil neutral frontier

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Radio Propagation and Wireless Coverage of LSAA-Based 5G Millimeter-Wave Mobile Communication Systems

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China Communications 2019年第5期16卷 1-18页

作者： haiming wang Peize Zhang Jing Li Xiaohu You School of Information Science and Engineering Southeast UniversityNanjing 211111China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 211111China National Mobile Communications Research Laboratory Southeast UniversityNanjing 211111China

Millimeter-wave(mm Wave) communications will be used in fifth-generation(5G) mobile communication systems, but they experience severe path loss and have high sensitivity to physical objects, leading to smaller cell radii and complicated network architectures. A coverage extension scheme using large-scale antenna arrays(LSAAs) has been suggested and theoretically proven to be cost-efficient in combination with ultradense small cell networks. To analyze and optimize the LSAA-based network deployments, a comprehensive survey of recent advances in statistical mmWave channel modeling is first presented in terms of channel parameter estimation, large-scale path loss models, and small-scale cluster models. Next, the measurement and modeling results at two 5G candidate mmWave bands(e.g., 28 GHz and 39 GHz) are reviewed and compared in several outdoor scenarios of interest, where the propagation characteristics make crucial contributions to wireless network designs. Finally, the coverage behaviors of systems employing a large number of antenna arrays are discussed, as well as some implications on future mmWave cellular network designs.

关键词： fifth generation (5G) channel modeling large-scale antenna array(LSAA) millimeter wave(mmWave) communications radio propagation measurements wireless coverage

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In-building coverage of millimeter-wave wireless networks from channel measurement and modeling perspectives

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Science China(Information Sciences) 2020年第8期63卷 5-20页

作者： Peize ZHANG Cheng YI Bensheng YANG Cheng-Xiang wang haiming wang Xiaohu YOU State Key Laboratory of Millimeter Waves Southeast University National Mobile Communications Research Laboratory Southeast University

To progress cost-effective deployment of millimeter-wave(mm Wave) wireless networks for indoor users, the prediction of indoor-to-indoor(I2I) and outdoor-to-indoor(O2I) coverage based on field measurement studies is of great interest to the future generation mobile communication system. First, measurements in I2I and O2I scenarios, which have advantages in terms of achieving a fair comparison of channel characteristics across different mm Wave bands and bandwidths, are performed. Next, the developed dual-slope path loss model with a break-point distance is found to well fit omnidirectional and directional measured I2I data, especially at 39.5 GHz, revealing that the transition from lit or shadow regions to totally blocked regions is abrupt. Combined with space-time propagation characteristics, the indoor blockage effect on path loss and angular spread is investigated, therein being essential for the design of beam-steering and tracking algorithms. Double-directional measurement results show that most dominant paths arrive along the line-ofsight path, and only a few in-building reflections can be detected in higher frequency bands. Based on the joint analysis of channel measurement and modeling results, several mm Wave network design and in-building coverage enhancement insights are presented.

关键词： building entry loss channel modeling in-building coverage millimeter-wave communication propagation measurements

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C band single pump photonic crystal fiber Raman amplifier

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Chinese Science Bulletin 2010年第6期55卷 555-559页

作者： JIANG haiming XIE Kang wang YaFei School of Optoelectronie Information University of Electronic Science and Technology of China Chengdu 610054 China

A novel twin-core photonic crystal fiber was proposed to reduce the complexity and cost of fiber Raman *** means of a proper design,this fiber could acquire a higher and flatter Raman gain efficiency coefficient curve rR=gR/Aeff over a specified band of wavelength than a conventional fiber.A Raman amplifier was designed with this novel twin-core photonic crystal fiber to operate in C band from 1530 nm to 1565 nm.A remarkable improvement over a conventional fiber Raman amplifier was *** was numerically demonstrated that when pumped with a single source,an average gain of 8.7 dB with a fluctuation of less than 0.9 dB is achievable.

关键词：光纤拉曼放大器光子晶体光纤 C波段单泵设计方法增益系数光纤波长复杂性

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Multiple-Sized Amphiphilic Janus Gold Nanoparticles by Ligand Exchange at Toluene/Water Interface

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Journal of Materials Science & Technology 2016年第8期32卷 733-737页

作者： Kun Luo Yongdong Xiang haiming wang Li Xiang Zhihong Luo Guangxi Key Laboratory of Universities for Clean Metallurgy Comprehensive Utilization of Nonferrous Metal Resource College of Materials Science and Engineering Guilin University of Technology

Amphiphilic Janus gold nanoparticles （GNPs） are prospected to encapsulate drug molecules in cancer therapy and to serve as heterogeneous catalysts at oil/water interfaces, where Janus GNPs with differ- ent sizes are required. In this work, multiple-sized precursor GNPs were synthesized by seeded growth method protected with tris（hydroxymethyl）phosphine oxide （THPO） ligand molecule, and a ligand ex- change reaction with triphenylphosphine （PPh3） at the toluene/water interface was employed to prepare amphiphilic Janus GNPs. UV-vis and transmission electron microscopy （TEM） analyses indicate that the as-prepared GNPs are nanocrystals with average diameters of 2.3 nm, 9.5 nm, 16.1 nm and 18.8 nm, re- spectively. Contact angle, Raman and X-ray photonic spectroscopy （XPS） analyses reveal that the self- assembled GNP films exhibit hydrophilic on one side and hydrophobic on another, owing to the adsorption of hydrophilic ligands （THPO and THP） and a similar amount of hydrophobic ligands （PPh3 and PPh30）. Angle-resolved XPS analysis further demonstrates that the individual GNPs actually possess hydro- philic and hydmphobic compartments on the surface, which regularly packed by supramolecular interactions at toluene/water interface to form the self-assembled GNP films.

关键词： Janus gold nanoparticles Amphipbilic Ligand exchange Self-assembly

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IEEE 802.11aj(45GHz):A New Very High Throughput Millimeter-Wave WLAN System

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China Communications 2014年第6期11卷 51-62页

作者： wang haiming HONG Wei CHEN Jixin SUN Bo PENG Xiaoming State Key Laboratory of Millimeter Waves Southeast University Strategy Planning Development ZTE Cooperation Institute for InfocommResearch(I2R)

This paper presents an overview of a new very high throughput millimeterwave WLAN system operating at 45 GHz band. We begin by reviewing standards process of IEEE 802.11aj(45GHz). Then the frequency spectrum allocation at 45 GHz band is introduced. Next, the channel measurement and mod-eling is given. Specifically, the millimeter-wave MIMO for physical layer enhancement is given in detail.

关键词： wireless local access network(WLAN) millimeter-wave very highthroughput 45 GHz mul-tiple-input andmultiple-output (MIMO)

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Application of the Modified Neighborhood Interference Model to the Cultivation of Forest and Herbaceous Ecosystem

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Wuhan University Journal of Natural Sciences 2008年第3期13卷 297-302页

作者： wang haiming LI Xianwei wang Haie Institute of Mountain Hazards and Environment ChineseAcademy of Sciences Chengdu 610041 Sichuan China College of Forestry and Horticultural Sichuan AgriculturalUniversity Ya＇an 625014 Sichuan China Department of Horticulture Sichuan Academy of AgriculturalScience Chengdu 610000 Sichuan China

This paper is an extension of the application of neighborhood interference model--being modified--to the study of the interference between forest plants and herbaceous plants. The exploration of the neighborhood interference between triploid Populus tomentosa and Lolium multiflorum shows that the interference of Lolium multiflorum on triploid populus tomentosa is positive, with the primary interference factor living weight, and secondary factor cover degree; the growth of an individual tree is affected by the number, height, and coverage of the Lolium multiflorum; the more dense the coverage of the Lolium multiflorum in a certain area, the taller, faster and more trees will grow as a result of a greater positive neighborhood interference. The modified neighborhood interference model well serves as an effective approach to extend the application of neighborhood interference researches.

关键词： forest and herbaceous ecosystem neighborhood interference conversion of farmland to forest

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