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Modulating Motor Behaviors by Electrical Stimulation of Specific Nuclei in Pigeons

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Journal of Bionic Engineering 2015年第4期12卷 555-564页

作者： Lei Cai Zhendong Dai Wenbo wang hao wang Yezhong Tang Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Shandong Provincial Key Laboratory of Biosensors Shandong Academy of Sciences Jinan 250014 China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu 610041 China

Pigeons （Columba livia） have excellent flying and orienting abilities and are ideal study subjects for biologists who re- search the underlying neurological mechanisms that modulate flying and allow birds to find their way home. These mechanisms also attract the engineers who want to apply pigeon locomotion to the design of flying robots. Here, we identified the mo- tor-related brain nuclei and revealed their relationship in spatial distribution in pigeons under light anesthesia and freely moving conditions respectively. Flapping and lateral body movements were successfully elicited when electrical microstimulation was applied to the diencephalon, medial part of the midbrain, and medulla oblongata of lightly anesthetized pigeons （N = 28） whose heads were fixed. The current thresholds for stimulating different nuclei and behavior ranged from 10 pA to 20 ~tA. During freely moving tests （N = 24）, taking off and turning were induced by a wireless stimulator through microelectrodes implanted in specific nuclei or brain regions. The results showed that electrical stimulation of these nuclei elicited the desired motor behavior. In addition, regulatory mechanisms were identified in the motor-related regions and nuclei of pigeons. Overlapping in the behavior elicited by stimulation of different regions indicates that complicated neural networks regulate motor behavior. Therefore, more studies need to be conducted involving simultaneous stimulation at multiple points within the nuclei involved in the networks.

关键词： Columba livia motor-related nuclei electrical microstimulation wireless stimulation system

Design and optimization of electrolyte flow fields in electrochemical machining of cross-channel array with tool vibration

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Chinese Journal of Aeronautics 2022年第4期35卷 461-472页

作者： Yan LIU Jia LIU Di ZHU hao wang College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

A metallic interconnect plate with a flow channel array is one of the most important elements in a solid oxide fuel cell(SOFC). Electrochemical machining(ECM) is considered to be an adoptable technology for fabricating flow channels in an interconnect plate on account of its efficiency and low cost. With respect to the traditional electrolyte flow mode in ECM cross-channel array, the electrolyte usually flows from one side to the opposite side of the rectangular processing area. However, obvious flow marks are typically formed at the bottom of channels perpendicular to the flow. According to multiphysical simulation analysis, the low electrolyte velocity in the channels perpendicular to the flow leads to uneven distribution of electrolyte products. To improve the uniformity of the flow field, two new electrolyte flow modes, “two-in and two-out” and “three-in and one-out”, are proposed. By adding one or two additional electrolyte inlets to the sides of the traditional flow field, the electrolyte flow velocity in the channels perpendicular to the traditional flow will be increased. Corresponding simulations and experiments were performed and the results showed that the “three-in and one-out” flow mode can produce a flatter bottom surface for the cross-channel array. Parameter optimization experiments for the preferred flow mode were undertaken and the optimal flow field parameters were determined.

关键词： Cross-channel array Dynamic simulation Electrochemical machining Flow field Interconnect plate

Effects of Post-Weld Heat Treatment on Microstructure and Mechanical Properties of Al-12.7Si-0.7Mg Alloy Welded Joints by GMAW

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Acta Metallurgica Sinica(English Letters) 2014年第2期27卷 245-252页

作者： Dong wang Changshu He hao wang Xiang Zhao Liang Zuo Key Laboratory of Anisotropy and Texture of Materials of Ministry of Education Northeastern University

In this study, 3-mm-thick hot-extruded plates of A1-12.7Si-0.7Mg alloy were used to fabricate the joints welded by gas metal arc welding. Effects of the post-weld heat treatment include solid solution treatment, water quenching, and artificial aging treatment on the microstructure, and mechanical properties of the weld joints have been investigated. Results showed that the welded joints after solid solution and artificial aging exhibited the increases in yield strength of 166 MPa and ultimate tensile strength of 148 MPa, respectively. Based on the microstructural observations, the associated mechanisms were discussed.

关键词： Al-Si alloy Welded joint Post-weld heat treatment (PWHT) Microstructure Mechanical property

Water dissipation mechanism of residential and office buildings in urban areas

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Science China(Technological Sciences) 2018年第7期61卷 1072-1080页

作者： ZHOU JinJun LIU JiaHong wang hao wang ZhongJing MEI Chao Department of Hydraulic Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China School of Transportation and Civil Engineering&Architecture Foshan UniversityGuangdong 528000China Engineering and Technology Research Center for Water Resources and Hydroceology of the Ministry of Water Resources Beijing 100038China

Indoor humidity directly impacts the health of indoor populations. In arid and semi-arid cities, the buildings indoor humidity is typically higher than outdoors, and the presence of water vapor results from water dissipation inside the buildings. Few studies have explored indoor humidity features and vapor distribution or evaluated water dissipation inside buildings. This study examined temperature and relative humidity （RH） changes in typical residential and office buildings. The results indicate a relatively stable temperature with vary range of-4-1~C and a fluctuation RH trend which is similarly to that of water use. We proposed the concept of building water dissipation to describe the transformation of liquid water into gaseous water during water consumption and to develop a building water dissipation model that involves two main parameters： indoor population and total floor area. The simulated values were verified by measuring water consumption and water drainage, and the resulting simulation errors were lower for residential than for office buildings. The results indicate that bathroom vapor accounts for 70% of water dissipation in residential buildings. We conclude that indoor humidity was largely a result of water dissipation indoors, and building water dissipation should be considered in urban hydrological cycles.

关键词： urban hydrology building water dissipation(BWD) water consumption indoor humidity

Clear-water local scouring around three piers in a tandem arrangement

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Science China(Technological Sciences) 2016年第6期59卷 888-896页

作者： wang hao TANG HongWu XIAO JiangFeng wang Yao JIANG Sheng State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China Huaihe River Commission of the Ministry of Water Resource Bengbu 233001 China

Experiments of local scouring around three piers were carried out under steady clear-water conditions. We investigated the role of pier spacing and flow rate in scour depth and progression. The scour-hole depth around the upstream pier was the same as that for single piers and independent of pier spacing. The scour behavior of the middle and downstream piers progressed through a synchronous scouring region, a transition region, and a radical deviation region as the fluid velocity increased. The critical velocity from the synchronous scouring region to the transition region for the middle and downstream piers was the same, which linearly increased with pier spacing. The degree of deviation in the radical deviation region for the middle and downstream piers was dependent on the pier spacing. The critical velocity from the transition region to the radical deviation region for the middle pier increased with the pier spacing. When the spacing was larger than 11 times the diameter of a pier, the scour depths of the three-pier configuration were the same as for the single piers, which indicates the limit of inter-pier fluid–structure interaction. Finally, the data from this study are used to derive adjustment factors to predict the local scour depth around three piers.

关键词： scouring piers critical velocity fluid-structure interaction

Multi-view Clustering: A Survey

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Big Data Mining and Analytics 2018年第2期1卷 83-107页

作者： Yan Yang hao wang the School of Information Science and Technology Southwest Jiaotong University

In the big data era, the data are generated from different sources or observed from different views. These data are referred to as multi-view data. Unleashing the power of knowledge in multi-view data is very important in big data mining and analysis. This calls for advanced techniques that consider the diversity of different views,while fusing these data. Multi-view Clustering(MvC) has attracted increasing attention in recent years by aiming to exploit complementary and consensus information across multiple views. This paper summarizes a large number of multi-view clustering algorithms, provides a taxonomy according to the mechanisms and principles involved, and classifies these algorithms into five categories, namely, co-training style algorithms, multi-kernel learning, multiview graph clustering, multi-view subspace clustering, and multi-task multi-view clustering. Therein, multi-view graph clustering is further categorized as graph-based, network-based, and spectral-based methods. Multi-view subspace clustering is further divided into subspace learning-based, and non-negative matrix factorization-based methods. This paper does not only introduce the mechanisms for each category of methods, but also gives a few examples for how these techniques are used. In addition, it lists some publically available multi-view ***, this paper serves as an introductory text and survey for multi-view clustering.

关键词： multi-view clustering co-training multi-kernel learning graph clustering subspace clustering subspace learning non-negative matrix factorization multi-task learning

Adaptive turning control for an agricultural robot tractor

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International Journal of Agricultural and Biological Engineering 2018年第6期11卷 113-119页

作者： hao wang Noboru Noguchi Graduate School of Agriculture Hokkaido UniversityKita 9 Nishi 9SapporoHokkaido065-8589Japan Research Faculty of Agriculture Hokkaido UniversityKita 9 Nishi 9SapporoHokkaido065-8589Japan

An adaptive turning algorithm for a four-wheel robot tractor in the headland is presented in this *** navigation sensors consisted of an inertial measurement unit and a real-time kinematic global positioning system(GPS).An objective function based on weights was used to create the navigation path,connecting by continuous *** asymmetric steering mechanism was then taken into consideration with a vehicle *** follow the path accurately,the slide movement of the robot and the steering rate were taken into account by estimating the turning radius in real *** addition,the vehicle model was tuned based on the results of each ***,the turning control algorithm was optimized on the basis of the specific conditions in the *** experiments showed that the robot tractor approached the next path with an average lateral deviation of 3.9 cm at a speed of 1.2 m/s during a *** to a conventional turning scheme,the time consumption and turning trajectory were decreased by 17%and 21%,respectively.

关键词： autonomous tractor path planning dynamic circle-back turning switch-back turning robot tractor reinforcement learning

Detection of internal crack growth in polyethylene pipe using guided wave ultrasonic testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 319-329页

作者： Jay Kumar Shah hao wang Said El-Hawwat Centre of Advanced Infrastructure and Transportation RutgersThe State University of New JerseyNJ 08854USA Department of Civil and Environmental Engineering RutgersThe State University of New JerseyNJ 08854USA

Despite the success of guided wave ultrasonic inspection for internal defect detection in steel pipes,its application on polyethylene(PE)pipe remains relatively *** growth of internal cracks in PE pipe severely affects its pressure-holding capacity,hence the early detection of internal cracks is crucial for effective pipeline maintenance *** study extends the scope of guided wave-based ultrasonic testing to detect the growth of internal cracks in a natural gas distribution PE *** experiments and a finite element model were planned to study the wave-crack interaction at different stages of axially oriented internal crack growth with a piezoceramic transducer-based setup arranged in a pitch-catch *** dispersion analysis supplemented with preliminary experiments was performed to isolate the optimal inspection frequency,leading to the selection of the T(0,1)mode at 50-kHz for the investigation.A transmission index based on the energy of the T(0,1)mode was developed to trace the extent of simulated crack *** findings revealed an inverse linear correlation between the transmission index and the crack depth for crack growth beyond 20%crack depth.

关键词： polyethylene pipes internal cracks guided wave ultrasonic testing torsional modes finite element modeling

Observation of ambipolar photoresponse from 2D MoS_(2)/MXene heterostructure

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Nano Research 2021年第10期14卷 3416-3422页

作者： Juntong Zhu hao wang Liang Ma Guifu Zou College of Energy Soochow Institute for Energy and Materials Innovationsand Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu ProvinceSoochow UniversitySuzhou 215006China Research Institute of Superconductor Electronics Nanjing UniversityNanjing 210023China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China

Two-dimensional materials have been demonstrated as promising toolboxes for *** metal carbides and nitrides(MXenes),members of an emerging family of two-dimensional materials,have drawn extensive attention in optoelectronics owing to their excellent conductivity and tunable electronic ***,a photodetector based on the two-dimensional van der Waals heterostructure of Ti_(3)C_(2)T_(x)MXene and a MoS_(2)monolayer was constructed to observe the ambipolar photoresponse,which showed a positive photoresponse in the visible spectrum(500-700 nm)and a negative photoresponse at longer wavelengths(700-800 nm).The device exhibited a high negative responsivity of 1.9 A/W and a detectivity of 2.1×10^(10)Jones under 750 nm light *** experiments demonstrate that the negative photoresponse arises from the heterostructureinduced trap energy level,which confines the excited photoelectrons and leads to an inverse *** work demonstrates a unique optoelectronic phenomenon in MoS_(2)/MXene heterostructures and provides valuable insights into the development of new photodetection materials.

关键词： MXene MoS_(2) two-dimensional heterostructure photodetector ambipolar photoresponse