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IABC: An iteratively automatic machine learning boosted hand-eye calibration method for laser displacement sensor

Chinese Journal of Aeronautics 2023年第8期36卷 422-453页

作者： Helin LI Bin LIN Tianyi SUI Liang XU Chen ZHANG Shuai YAN Yang WANG Xinquan HAO Deyu LOU School of Mechanical Engineering Ministry of EducationTianjin UniversityTianjin 300350China International Institute for Innovative Design and Intelligent Manufacturing of Tianjin University Shaoxing 312000China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing 100076China Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of Education Tianjin UniversityTianjin 300072China

An on-machine measuring(OMM)system with a laser displacement sensor(LDS)is designed for measuring free-form surfaces of hypersonic aircraft’s *** improve the measurement accuracy of the OMM system,a novel Iteratively Automatic machine learning Boosted hand-eye Calibration(IABC)method is *** the hand-eye relationship and LDS measurement errors can be calibrated in one calibration process without any hardware changes via ***,a new objective function is derived,containing analytical parameters of the handeye relationship and LDS ***,a hybrid calibration model composed of two kernels is proposed to solve the objective *** kernel is the analytical kernel designed for solving analytical *** kernel is the automatic machine learning(AutoML)kernel designed to model LDS *** two kernels are connected with stepwise iterations to find the best calibration *** with traditional methods,hand-eye experiments show that IABC reduces the calibration RMSE by about 50%.Verification experiments show that IABC reduces the measurement deviations by about 25%-50%and RMSEs within 40%.Even when the training data are obviously less than the test data,IABC performs *** demonstrate that IABC is more accurate than traditional hand-eye methods.

关键词： Hand-Eye Calibration Laser Displacement Sensor Machine learning Measurement errors On-Machine Measurement

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design strategy and relevant flow mechanisms of highly loaded 3D compressor tandem cascades

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Chinese Journal of Aeronautics 2024年第7期37卷 220-235页

作者： Xiaochen MAO Yunyu WANG Zhihua DING Hao CHENG Bo LIU School of Power and Energy Northwestern Polytechnical UniversityXi’an 710129China The National Key Laboratory of Science and Technology on Aerodynamic Design and Research Xi’an 710129China Xi’an Thermal Power Research Institute Co.Ltd Xi’an 710072China

To investigate the design strategy of highly loaded tandem cascades at both the midspan and endwall,the overall performance and flow mechanisms of four typical tandem cascades based on the optimization were analyzed from multiple perspectives *** results show that the interference effects on the Front Blade(FB)and Rear Blade(RB)should not be overlooked during the design phase,and the design strategies at the midspan and endwall are completely *** the midspan,the optimization aims to increase the interference effects and the strength of the gap jet while maintaining the same load on the FB and ***,the endwall optimal airfoil exhibits weakening interference effects,advancement of the gap jet location,and load transfer from the FB to *** further analysis of flow characteristics,the midspan optimal airfoil is beneficial for inhibiting the low-energy fluid from interacting with the suction surface of RB under the design condition,but results in earlier occurrence of corner *** endwall optimal airfoil helps suppress the development of the secondary flow and delay the onset of corner ***,by combining the benefits of these two design approaches,additional forward sweep effects are achieved,further enhancing the performance of the tandem cascade.

关键词： Tandem cascade Interference effect Vortex structure Load split Compressor

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Study on the Influence of Microclimate Comfort on the Winter Vigor of Campus Open Space in Severe Cold Areas—Taking the Campus of Harbin Institute of technology as an Example 5th

Study on the Influence of Microclimate Comfort on the Winter...

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5th International Conference on Resources and Environmental Research, ICRER 2023

作者： Yan, Yuhang Jin, Hong Key Laboratory of Cold Region Urban and Rural Human Settlement Environment Science and Technology Ministry of Industry and Information Technology School of Architecture and Design Harbin Institute of Technology Heilongjiang Harbin150001 China

ISBN: (纸本)9783031563584

The outdoor thermal comfort of university campuses is an important factor in encouraging students to engage in outdoor activities and. The cold climate conditions in severe cold areas have affected the degree of use and vitality of open campus spaces. This study took Harbin Institute of technology as the research object. Through monitoring the space thermal environment, questionnaire survey, attendance and activity behavior observation, the influence of open space thermal comfort on the duration of winter participants and the frequency of space activity in cold regions was explored. The results indicate that: (1) Landscape types and components have a significant impact on the outdoor thermal environment and human thermal comfort. (2) The outdoor neutral temperature in Harbin during winter is 12.78 °C, with a neutral UTCI range of 3.7 °C to 21.8 °C. (3) The average activity duration of students reaches its maximum value (11 min) when the UTCI is -7 °C. When UTCI > −14 °C, the average duration of student activities will exceed 10 min. (4) TSV is proportional to frequency. The rich landscape environment and rest facilities can increase the frequency of activities. These results can provide reference for designing improved campus spaces to promote students’ outdoor activities, enhance spatial vitality, and ensure health. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.

关键词： Students

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Dynamic Properties of Steel Catenary Riser near Touchdown Point Under Coplanar Vessel Heave and Vortex Induced Vibration

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China Ocean Engineering 2023年第2期37卷 288-298页

作者： ZHANG Xiang-rui WANG Kun-peng JIANG Da-peng TANG Kai LI Yu-long Marine Design and Research Institute of China Shanghai 200011China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 510275China

The present study establishes a simple numerical model for the coupled response of a steel catenary riser(SCR) subjected to coplanar vessel motion and vortex-induced vibration(VIV). Owing to the large deflection of the SCR, the geometric nonlinearity is considered in this model. The hydrodynamic force comprises the excitation force and hydrodynamic damping, where the excitation force that only exists when the non-dimensional frequency is located in the lock-in range, is associated with the VIV. The hydrodynamic force model is validated based on the published VIV test *** for the seabed resistance at the touchdown zone(TDZ), integrated with an initial seabed trench, the hysteretic feature is modeled. Based on the model, the study emphasizes on the coupled response characteristics near the touchdown point(TDP) induced by coplanar vessel heave and VIV, and analyzes the sensitivity of the coupled response to the heaving amplitude and frequency. It is found that with the increase of the heave amplitude and frequency, the VIV can be obviously mitigated, but the heave-related response in the coupled analysis seems to be close to that in the heave-only simulation. Finally, the fatigue damage near TDP is parametrically investigated based on the separate analysis and the coupled analysis. The results demonstrate that the coupled effect plays a significant role in the fatigue assessment near TDP. Besides, the proportion of the coupled effect accounting for the total fatigue damage decreases with the increasing seabed stiffness, while increases with the increasing seabed trench depth.

关键词： vessel heave vortex induced vibration coupled effect steel catenary riser(SCR)-seabed interaction seabed trench

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A Compact H-Plane Ten-Way Waveguide Power Divider

A Compact H-Plane Ten-Way Waveguide Power Divider

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2023 IEEE MTT-S International Microwave Workshop Series on Advanced Materials and Processes for RF and THz Applications, IMWS-AMP 2023

作者： Yang, Jingxian Yang, Meng Chen, Junfeng China Ship Development and Design Center Science and Technology on Electromagnetic Compatibility Laboratory Wuhan China

ISBN: (纸本)9798350308761

In this paper, a compact H-plane ten-way waveguide power divider is designed. By adding matching pins and matching blocks, the S11 is less than -15dB in the frequency range of 1.88GHz-1.92GHz on the H-plane of the waveguide. The 10 output ports of the power divider have good amplitude and phase consistency. The amplitude difference is less than 0.7dB, and the phase difference is less than 10 degrees. The power divider has the characteristics of miniaturization, whose interval between adjacent output ports is λg/2 (λg is the guide wavelength of rectangular waveguide). © 2023 IEEE.

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design and Optimisation of Strong Electromagnetic Pulse Protection Devices Based on Semiconductors and Gas Discharges Tube

Design and Optimisation of Strong Electromagnetic Pulse Prot...

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2023 Cross Strait Radio science and Wireless technology Conference, CSRSWTC 2023

作者： Wang, Qingyao Wang, Dongdong Yang, Yuanpeng Fang, Chonghua China Ship Development and Design Centre Science and Technology on Electromagnetic Compatibility Laboratory Wuhan China

ISBN: (纸本)9798350358971

RF front-end equipment in the face of strong electromagnetic pulse becomes unbearable, in order to protect the circuit sensitive equipment from damage, the actual research often use some semiconductor devices and switching devices in the circuit front-end design protection module. This paper combines transient voltage suppressors and gas discharge tubes for strong EMP protection, and discusses the impact of the number of TVS tubes on the protection module. After simulation experiments, the increase in the number of TVS tubes can reduce the full response time of the module and increase the effect of pulse protection, and the full response time of the module is less than 40ns and the protection effect is more than 36.9dB when 5 TVS tubes are connected in parallel. © 2023 IEEE.

关键词： gas discharge tubes high frequency electromagnetic pulse Strong EMP Protection transient voltage suppressors

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A Reflective Ultra-Broadband Polarized Rotating Surface with Simple Structure

A Reflective Ultra-Broadband Polarized Rotating Surface with...

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2023 International Applied Computational Electromagnetics Society Symposium, ACES-China 2023

作者： Qiao, Jianpu Ji, Hang Wu, Weijun Zeng, Xianliang Science and Technology on Electromagnetic Compatibility Laboratory China Ship Development and Design Centre Wuhan China

ISBN: (纸本)9781733509657

In this paper, a reflective ultra-broadband linearly polarized rotating artificial electromagnetic material is proposed. Its unit is composed of a double-opening resonant ring and a metal ground sheet separated by a dielectric substrate. Simulation results show that the polarized rotating surface(PRS) can resonate at three frequencies under incident electromagnetic waves, which leads to an increase in the bandwidth of cross-polarized reflections. The designed polarization rotation surface can convert the line polarization electromagnetic wave to its cross-polarization electromagnetic wave in the frequency range of 6.25 GHz18.95 GHz with a relative bandwidth of 100% and the polarization rotation efficiency is greater than 90% throughout the bandwidth. The proposed polarization rotation surface has an extremely simple geometry and a wider bandwidth compared to the currently published related designs. Therefore, this reflective polarization rotation surface has potential applications in areas such as polarization control. © 2023 Applied Computational Electromagnetics Society (ACES).

关键词： Dielectric materials

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design of the Wideband Cone-and-Ground-Plane Chamber with Multi-Resistor Loaded

Design of the Wideband Cone-and-Ground-Plane Chamber with Mu...

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2023 Cross Strait Radio science and Wireless technology Conference, CSRSWTC 2023

作者： Wang, Xinyi Liu, Feng Peng, Zhihe China Ship Development and Design Center Science and Technology on Electromagnetic Compatibility Laboratory Wuhan China

ISBN: (纸本)9798350358971

The cone-and-ground-plane structure is suitable for electric field probe calibration because of the wide frequency band and traveling wave inside during the time window. However the truncation at the end causes the reflection from the cone and ground panel, which will overlap on the main waveform, resulting in significant distortion of the standard electric field waveform. In this paper, a cone-and-ground-plane chamber is designed with multi-resistor loaded between the cone apex and ground panel edge to absorb end reflection. Besides, absorbent material of ferrite is laid around and at the bottom of the chamber to avoid the influence of external electromagnetic interference on the standard field. The simulated results show that the cone-and- ground-plane chamber designed in this paper has good voltage reflection coefficient among wide frequency band. © 2023 IEEE.

关键词： cone-and-ground-plane structure electric field probe calibration

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Ozonation of aromatic monomer compounds in water: factors determining reaction outcomes

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Frontiers of Environmental science & Engineering 2023年第5期17卷 13-25页

作者： Zhe Wang Wenjuan Zhang Zhiwei Wang Jing Chang School of Environmental Science and Safety Engineering Tianjin University of TechnologyTianjin 300384China School of Environmental and Municipal Engineering Tianjin Key Laboratory of Aquatic Science and TechnologyTianjin Chengjian UniversityTianjin 300384China Tianjin Municipal Engineering Design&Research Institute Co. Ltd.Tianjin 300384China

For aromatic monomer compounds (AMCs), ozonation outcomes were usually predicted by the substituents of the benzene ring based on the electron inductive effect. However, the predicted results were occasionally unreliable for complex substituents, and other factors caused concern. In this study, p-chloronitrobenzene (p-CNB) and ibuprofen (IBP) were selected for ozonation. According to the electron inductive theory, p-CNB should be less oxidizable, but the opposite was true. The higher rates of p-CNB were due to various sources of assistance. First, the hydroxyl radical (•OH) contributed 90 % to p-CNB removal at pH 7.0, while its contribution to IBP removal was 50 %. Other contributions came from molecular O3 oxidation. Second, p-CNB achieved 40 % of the total organic carbon (TOC) removal and fewer by-product types and quantities, when compared to the results for IBP. Third, the oxidation of p-CNB started with hydroxyl substitution reactions on the benzene ring;then, the ring opened. However, IBP was initially oxidized mainly on the butane branched chain, with a chain-shortening process occurring before the ring opened. Finally, the degradation pathway of p-CNB was single and consumed fewer oxidants. However, both branches of IBP were attacked simultaneously, and three degradation pathways that relied on more oxidants were proposed. All of these factors were determinants of the rapid removal of p-CNB.

关键词： Ozonation Aromatic compound Oxidizing specie By-product Initial reaction position Degradation pathway

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A Fast Simulation Method in Range-Doppler Domain for Airborne Radar Clutter 7

A Fast Simulation Method in Range-Doppler Domain for Airborn...

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7th IEEE International Symposium on Electromagnetic Compatibility, ISEMC 2023

作者： Zhili, Wang Li, Tao Tong, Cheng China Ship Development and Design Center Science and Technology on Electromagnetic Compatibility Laboratory Wuhan China

ISBN: (纸本)9798350333107

The technology of clutter simulation is essential in radar design and electromagnetic environmental effects analysis. To meet the requirement for real-time simulation, a fast clutter simulation method for airborne radar is proposed in this paper. By simplifying the clutter model in range-Doppler domain, the dimension of the clutter simulation data is reduced. And a fast simulation method in range-Doppler domain is proposed. Compared with the traditional method, the computational complexity of the RD(Range-Doppler) method proposed in this paper is significantly decreased. The simulation results show that the RD method proposed in this paper has improved efficiency while ensuring simulation accuracy. © 2023 IEEE.

关键词： Radar clutter

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