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Chinese Journal of Mechanical Engineering 2024年第1期37卷 203-214页

作者： Xiaokang Huang Xiaoyong Tian Qi Zhong Shunwen He Cunbao Huo Yi Cao Zhiqiang Tong Dichen Li State Key Laboratory of Manufacturing Systems Engineering Xi’an Jiaotong UniversityXian 710049China

Improvement of fabrication efficiency and part performance was the main challenge for the large-scale powder bed fusion(PBF)*** this study,a dynamic monitoring and feedback system of powder bed temperature field using an infrared thermal imager has been established and integrated into a four-laser PBF equipment with a working area of 2000 mm×2000 *** heat-affected zone(HAZ)temperature field has been controlled by adjusting the scanning speed ***,the relationship among spot size,HAZ temperature,and part performance has been *** fluctuation of the HAZ temperature in four-laser scanning areas was decreased from 30.85℃to 17.41℃.Thus,the consistency of the sintering performance of the produced large component has been *** on the controllable temperature field,a dynamically adjusting strategy for laser spot size was proposed,by which the fabrication efficiency was improved up to 65.38%.The current research results were of great significance to the further industrial applications of large-scale PBF equipment.

关键词： Powder bed fusion Efficiency Large-scale Spot size Heat-affected zone(HAZ)

A novel rapid cooling assembly design in a high-pressure cubic press apparatus

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Matter and Radiation at Extremes 2024年第2期9卷 98-104页

作者： Peiyan Wu Yongjiang Xu Yanhao Lin Center for high Pressure Science and technology Advanced research Beijing 100193People’s Republic of China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083People’s Republic of China

In traditional high-pressure–temperature assembly design, priority has been given to temperature insulation and retention at high *** limits the efficiency of cooling of samples at the end of experiments, with a negative impact on many studies in high-pressure Earth andplanetary science. Inefficient cooling of experiments containing molten phases at high temperature leads to the formation of quench textures,which makes it impossible to quantify key compositional parameters of the original molten phase, such as their volatile contents. Here,we present a new low-cost experimental assembly for rapid cooling in a six-anvil cubic press. This assembly not only retains high heatingefficiency and thermal insulation, but also enables a very high cooling rate (∼600 ℃/s from 1900 ℃ to the glass transition temperature).Without using expensive materials or external modification of the press, the cooling rate in an assembly (∼600 ℃/s) with cube lengths of38.5 mm is about ten times faster than that in the traditional assembly (∼60 ℃/s). Experiments yielding inhomogeneous quenched melttextures when the traditional assembly is used are shown to yield homogeneous silicate glass without quench textures when the rapid coolingassembly is used.

关键词： cubic insulation apparatus

Rapid Degrading Carbamazepine in a Novel Advanced Oxidation Process of Bisulfite Activated by Lithium Cobaltate Recovered from Spent Lithium-ion Battery

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Chemical research in Chinese Universities 2024年第1期40卷 127-135页

作者： Yan Jiali Yang Kaiying Wang Xi Zhai Jinli Zhu Wenjie Yang Daoli Luo Yongming Gao Xiaoya Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming650500P.R.China Innovation Team for Volatile Organic Compounds Pollutants Control and Resource Utilization of Yunnan Province Kunming650500P.R.China higher Educational Key Laboratory for Odorous Volatile Organic Compounds Pollutants Control of Yunnan Province Kunming650500P.R.China

Maximizing the sustainable recycling of spent lithium-ion batteries(LIBs)shows economic and environmental *** study recovered lithium cobaltate(LiCoO_(2),LCO)from spent LIBs cathode *** recovered LCO was then combined with NaHSO_(3)to remove refractory organic pollutants of carbamazepine(CBZ)in *** degradation of CBZ reached 80.0%within 60 min,by 1O_(2),SO_(4),OH and O_(2)^(-)generated in the LCO/NaHSO_(3)*** electron transfer between Co(III)and Co(II)was beneficial to the generation of free *** LCO/NaHSO_(3)degraded CBZ effectively in both secondary outlet water and tap ***,high concentrations of inorganic ions(Cl^(−),HCO_(3)^(-),HPO_(4)^(2-),SO_(2)−4,NO_(3)^(-))and natural organic matter(humic acid,HA)could inhibit the degradation of *** three cycles,the stability of the LCO/NaHSO_(3)system was demonstrated by the maintained high efficiency in the degradation of *** obtained data indicate that the LCO/NaHSO_(3)system holds great application potential in the field of advanced oxidation degradation of pollutants.

关键词： Spent lithium-ion battery Lithium cobaltate Carbamazepine NaHSO_(3) Advanced oxidation

Tuning the membrane rejection behavior by surface wettability engineering for an effective water-in-oil emulsion separation

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Chinese Chemical Letters 2024年第6期35卷 480-485页

作者： Yan Zou Yin-Shuang Hu Deng-Hui Tian Hong Wu Xiaoshu Lv Guangming Jiang Yu-Xi Huang Engineering research Center for Waste Oil Recovery technology and Equipment Ministry of EducationChongqing Technology and Business UniversityChongqing 400067China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation technology(Sun Yat-sen University) Guangzhou 510275China

Membrane-based separation is a promising technology to eliminate water impurities from the oil ***,it remains a great challenge to separate water from highly emulsified viscous oil owing to the high stability of the water droplets in *** we report a surface wettability engineering on an alumina ceramic membrane to achieve an efficient separation of a water-in-oil(W/O)*** with different carbon chain lengths and fluorinated status were introduced to endow the alumina membrane with different surface *** all the modified membranes exhibited excellent separation of the W/O without Span 80(surfactant),the one with amphiphobic wettability and lowest surface energy failed to separate the Span 80 stabilized W/*** presence of Span 80 reduced the interfacial tension of water droplets,making them easier to deform and penetrate the modified membrane with the lowest surface *** reveals that engineering proper surface wettability is the key to separating the oil and water ***,the modified membranes maintained decent separation performance and stability under long-term run separation of the emulsified W/O.

关键词： Water-in-oil emulsion Ceramic membrane Membrane separation Surface wettability

Adaptive Optimal Discrete-Time Output-Feedback Using an Internal Model Principle and Adaptive Dynamic Programming

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 131-140页

作者： Zhongyang Wang Youqing Wang Zdzisław Kowalczuk the College of Information Science and technology Beijing University of Chemical TechnologyBeijing 100029China IEEE the Department of Robotics and Decision Systems Faculty of ElectronicsTelecommunications and InformaticsGdańsk University of TechnologyGdansk 80-233Poland

In order to address the output feedback issue for linear discrete-time systems, this work suggests a brand-new adaptive dynamic programming(ADP) technique based on the internal model principle(IMP). The proposed method, termed as IMP-ADP, does not require complete state feedback-merely the measurement of input and output data. More specifically, based on the IMP, the output control problem can first be converted into a stabilization problem. We then design an observer to reproduce the full state of the system by measuring the inputs and outputs. Moreover, this technique includes both a policy iteration algorithm and a value iteration algorithm to determine the optimal feedback gain without using a dynamic system model. It is important that with this concept one does not need to solve the regulator equation. Finally, this control method was tested on an inverter system of grid-connected LCLs to demonstrate that the proposed method provides the desired performance in terms of both tracking and disturbance rejection.

关键词： Adaptive dynamic programming(ADP) internal model principle(IMP) output feedback problem policy iteration(PI) value iteration(VI)

A Distortion Self-Calibration Method for Binocular high Dynamic Light Adjusting and Imaging System Based on Digital Micromirror Device

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2036-2038页

作者： Pei Wu Yanjie Wang Honghai Sun Zhuoman Wen University of Chinese Academy of Sciences Beijing 100049and NIO Inc.Shanghai 200000China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China

Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical design of the system, the causes of the distortion are given and a distortion model is established. Then, a quick and accurate self-calibration method is designed. The experiments indicate that the method can calibrate the two image sensors of the system at the same time,the average pixel deviation of the calibrated system is less than 0.5pixels and the maximum deviation is less than 1 pixel.

关键词： Dynamic system deviation

Electronic structures and Mott state of epitaxial TaS_(2) monolayers

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Science china(Physics,Mechanics & Astronomy) 2024年第5期67卷 91-97页

作者： Qichao Tian Chi Ding Xiaodong Qiu Qinghao Meng Kaili Wang Fan Yu Yuyang Mu Can Wang Jian Sun Yi Zhang national Laboratory of Solid State Microstructure School of PhysicsNanjing UniversityNanjing 20093China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China Hefei national Laboratory Hefei 230088China

Layered material TaS2hosts multiple structural phases and exotic correlated quantum states,including charge density wave(CDW),superconductivity,quantum spin liquid,and Mott insulating ***,we synthesized TaS_(2)monolayers in H and T phases using the molecular beam epitaxial(MBE)method and studied their electronic structures via angle-resolved photoemission spectroscopy(ARPES).We found that the H phase TaS_(2)(H-TaS_(2))monolayer is metallic,with an energy band crossing the Fermi *** contrast,the T phase TaS_(2)(T-TaS_(2))monolayer shows an insulated energy gap at the Fermi level,while the normal calculated band structure implies it should be metallic without any band ***,by considering Hubbard interaction potential U,further density functional theory(DFT)calculation suggests that monolayer T-TaS_(2)could be a CDW Mott insulator,and the DFT+U calculation matches well with the ARPES *** significantly,the temperature-dependent ARPES result indicates that the CDW Mott state in the T-TaS_(2)monolayer is more robust than its bulk counterpart and can persist at room *** results reveal that the dimensional effect can enhance the CDW Mott state and provide valuable insights for further exploring the exotic properties of monolayer TaS2.

关键词： temperature monolayer state

Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression

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china Ocean Engineering 2024年第2期38卷 313-325页

作者： DONG Wen-bo ZHOU Li DING Shi-feng WANG Ai-ming CAI Jin-yan School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of *** the Arctic,merchant ships with low ice class often navigate in channels opened up by *** in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large *** ship may get stuck if steered into ice fields off the *** this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable *** this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point *** first stage employs the image segmentation method to extract channel *** the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression *** training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel *** evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second.

关键词： ice channel ship navigation identification image segmentation corner point regression

Downscaling Seasonal Precipitation Forecasts over East Africa with Deep Convolutional Neural Networks

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Advances in Atmospheric Sciences 2024年第3期41卷 449-464页

作者： Temesgen Gebremariam ASFAW Jing-Jia LUO Institute for Climate and Application research(ICAR)/CIC-FEMD/KLME/ILCEC Nanjing University of Information Science and TechnologyNanjing 210044China Institute of Geophysics Space Science and Astronomy Addis Ababa UniversityAddis Ababa 1176Ethiopia

This study assesses the suitability of convolutional neural networks(CNNs) for downscaling precipitation over East Africa in the context of seasonal forecasting. To achieve this, we design a set of experiments that compare different CNN configurations and deployed the best-performing architecture to downscale one-month lead seasonal forecasts of June–July–August–September(JJAS) precipitation from the Nanjing University of Information Science and technology Climate Forecast System version 1.0(NUIST-CFS1.0) for 1982–2020. We also perform hyper-parameter optimization and introduce predictors over a larger area to include information about the main large-scale circulations that drive precipitation over the East Africa region, which improves the downscaling results. Finally, we validate the raw model and downscaled forecasts in terms of both deterministic and probabilistic verification metrics, as well as their ability to reproduce the observed precipitation extreme and spell indicator indices. The results show that the CNN-based downscaling consistently improves the raw model forecasts, with lower bias and more accurate representations of the observed mean and extreme precipitation spatial patterns. Besides, CNN-based downscaling yields a much more accurate forecast of extreme and spell indicators and reduces the significant relative biases exhibited by the raw model predictions. Moreover, our results show that CNN-based downscaling yields better skill scores than the raw model forecasts over most portions of East Africa. The results demonstrate the potential usefulness of CNN in downscaling seasonal precipitation predictions over East Africa,particularly in providing improved forecast products which are essential for end users.

关键词： East Africa seasonal precipitation forecasting downscaling deep learning convolutional neural networks(CNNs)

CRD-CGAN:category-consistent and relativistic constraints for diverse text-to-image generation

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Frontiers of Computer Science 2024年第1期18卷 61-75页

作者： Tao HU Chengjiang LONG Chunxia XIAO College of Intelligent Systems Science and Engineering Hubei Minzu UniversityEnshi 445000China School of Computer Science Wuhan UniversityWuhan 430072China Key Laboratory of Performing Art Equipment&System technology Ministry of Culture and TourismBeijing 100007China Meta Reality Labs BurlingameCA94010USA

Generating photo-realistic images from a text description is a challenging problem in computer *** works have shown promising performance to generate synthetic images conditional on text by Generative Adversarial Networks(GANs).In this paper,we focus on the category-consistent and relativistic diverse constraints to optimize the diversity of synthetic *** on those constraints,a category-consistent and relativistic diverse conditional GAN(CRD-CGAN)is proposed to synthesize K photo-realistic images *** use the attention loss and diversity loss to improve the sensitivity of the GAN to word attention and ***,we employ the relativistic conditional loss to estimate the probability of relatively real or fake for synthetic images,which can improve the performance of basic conditional ***,we introduce a category-consistent loss to alleviate the over-category issues between K synthetic *** evaluate our approach using the Caltech-UCSD Birds-200-2011,Oxford 102 flower and MS COCO 2014 datasets,and the extensive experiments demonstrate superiority of the proposed method in comparison with state-of-the-art methods in terms of photorealistic and diversity of the generated synthetic images.

关键词： text-to-image diverse conditional GAN relativi-stic category-consistent