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Inverse Calculation and Regularization Process for the Solar Aspect System(SAS) of HXI Payload on ASO-S Spacecraft

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Research in Astronomy and Astrophysics 2024年第4期24卷 13-34页

作者： Ji-rui Yu Ping Ruan Yang Su Ying-Hong He jin-You tao Zhe zhang song Guo bin xue Jian-Feng Yang Xi'an Institute of Optics and Precision Mechanics of Chinese Academy of Sciences Xi'an 710119China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 20034China School ofAstronomy and Space Science Universityof Science and Technology of ChinaHefei 230026China

For the ASO-S/HXI payload, the accuracy of the flare reconstruction is reliant on important factors such as the alignment of the dual grating and the precise measurement of observation orientation. To guarantee optimal functionality of the instrument throughout its life cycle, the Solar Aspect System (SAS) is imperative to ensure that measurements are accurate and reliable. This is achieved by capturing the target motion and utilizing a physical model-based inversion algorithm. However, the SAS optical system’s inversion model is a typical ill-posed inverse problem due to its optical parameters, which results in small target sampling errors triggering unacceptable shifts in the solution. To enhance inversion accuracy and make it more robust against observation errors, we suggest dividing the inversion operation into two stages based on the SAS spot motion model. First, the as-rigid-aspossible (ARAP) transformation algorithm calculates the relative rotations and an intermediate variable between the substrates. Second, we solve an inversion linear equation for the relative translation of the substrates, the offset of the optical axes, and the observation orientation. To address the ill-posed challenge, the Tikhonov method grounded on the discrepancy criterion and the maximum a posteriori (MAP) method founded on the Bayesian framework are utilized. The simulation results exhibit that the ARAP method achieves a solution with a rotational error of roughly±3 5 (1/2-quantile);both regularization techniques are successful in enhancing the stability of the solution, the variance of error in the MAP method is even smaller—it achieves a translational error of approximately±18μm (1/2-quantile) in comparison to the Tikhonov method’s error of around±24μm (1/2-quantile). Furthermore, the SAS practical application data indicates the method’s usability in this study. Lastly, this paper discusses the intrinsic interconnections between the regularization methods.

关键词： methods:data analysis Sun:flares Sun:X-rays gamma rays

Enhancing Evolutionary Algorithms With Pattern Mining for Sparse Large-Scale Multi-Objective Optimization Problems

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1786-1801页

作者： Sheng Qi rui Wang tao zhang Weixiong Huang Fan Yu ling Wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China College of Systems Engineering National University of Defense TechnologyChangsha 410073and also with the Xiangjiang LaboratoryChangsha 410205China College of Transportation and Engineering Central South UniversityChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China

Sparse large-scale multi-objective optimization problems(SLMOPs)are common in science and ***,the large-scale problem represents the high dimensionality of the decision space,requiring algorithms to traverse vast expanse with limited computational ***,in the context of sparse,most variables in Pareto optimal solutions are zero,making it difficult for algorithms to identify non-zero variables *** paper is dedicated to addressing the challenges posed by *** start,we introduce innovative objective functions customized to mine maximum and minimum candidate *** substantial enhancement dramatically improves the efficacy of frequent pattern *** this way,selecting candidate sets is no longer based on the quantity of nonzero variables they contain but on a higher proportion of nonzero variables within specific ***,we unveil a novel approach to association rule mining,which delves into the intricate relationships between non-zero *** novel methodology aids in identifying sparse distributions that can potentially expedite reductions in the objective function *** extensively tested our algorithm across eight benchmark problems and four real-world *** results demonstrate that our approach achieves competitive solutions across various challenges.

关键词： Evolutionary algorithms pattern mining sparse large-scale multi-objective problems(SLMOPs) sparse large-scale optimization.

A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1342-1357页

作者： Sheng Qi rui Wang tao zhang Xu Yang ruiqing Sun ling Wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China Xiangjiang Laboratory Changsha 410205China College of Computer National University of Defense TechnologyChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China IEEE

Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are *** a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec ***,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables ***,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is *** data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between *** by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these *** mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast ***-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed.

关键词： Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.

Surface quality investigation in high-speed dry milling of Ti-6Al-4V by using 2D ultrasonic-vibration-assisted milling platform

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Advances in Manufacturing 2024年第2期12卷 349-364页

作者： jin zhang Li ling Qian-Yue Wang xue-Feng Huang Xin-Zhen Kang Gui-Bao tao Hua-Jun Cao College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing400044People’s Republic of China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing400044People’s Republic of China Aerospace Research Institute of Materials and Processing Technology Beijing100076People’s Republic of China

Ultrasonic-vibration-assisted milling(UVAM)is an advanced method for the efficient and precise machining of difficult-to-machine materials in modern ***,the milling efficiency is limited because the ultrasonic vibration toolholder ER16 collet has a critical cutting ***,a 2D UVAM platform is built to ensure precision machining efficiency and improve the surface quality without changing the milling *** evaluate this 2D UVAM platform,ultrasonic-vibration-assisted high-speed dry milling(UVAHSDM)is performed to process a titanium alloy(Ti-6Al-4V)on the platform,and the milling temperature,surface roughness,and residual stresses are selected as the important indicators for performance *** results show that the intermittent cutting mechanism of UVAHSDM combined with the specific spindle speed,feed speed,and vibration amplitude can reduce the milling temperature and improve the texture of the machined *** with conventional milling,UVAHSDM reduces surface roughness and peak-groove surface profile values and extends the range of residual surface compressive stresses from−413.96 MPa to−600.18 *** excellent processing performance demonstrates the feasibility and validity of applying this 2D UVAM platform for investigating surface quality achieved under UVAHSDM.

关键词： 2D ultrasonic-vibration-assisted milling(UVAM)platform Ultrasonic-vibration-assisted high-speed dry milling(UVAHSDM) Milling temperature Surface roughness Residual stress

Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research International 2024年第2期31卷 475-487页

作者： shi-guang Xu jin-shan He Run-ze zhang Fu-cheng zhang Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation *** order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain ***,the effect of holding time on static recrystallization behaviors is significantly controlled by *** addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to *** cSRX exists at all *** is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of *** undissolved sigma precipitates promote static recrystallization through particle-stimulated ***,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： rui Wang Zhiming Zhou Kaiwen Li tao zhang ling Wang Xin Xu Xiangke Liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning

Passive neutron multiplicity device for^(240)Pu measurement based on FPGA

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Nuclear Science and Techniques 2024年第9期35卷 141-154页

作者： Yan zhang Hao-Ran zhang Ren-Bo Wang ming-Yu Li rui Chen Hai-tao Wang Xiang-Ting Meng Shu-Min Zhou bin Tang Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of TechnologyNanchang 330013China Engineering Research Center for Nuclear Technology Application Ministry of EducationEast China University of TechnologyNanchang 330013China Pan China Detect Technology Co.Ltd. Nanchang 330013China

A passive neutron multiplicity measurement device,FH-NCM/S1,based on field-programmable gate arrays(FPGAs),is developed specifically for measuring the mass of plutonium-240(^(240)Pu)in mixed oxide ***-NCM/S1 adopts an inte-grated approach,combining the shift register analysis mode with the pulse-position timestamp mode using an *** optimal effective length of the^(3)He neutron detector was determined to be 30 cm,and the thickness of the graphite reflector was ascertained to be 15 cm through MCNP *** fabricating the device,calibration measurements were per-formed using a^(252)Cf neutron source;a detection efficiency of 43.07%and detector die-away time of 55.79μs were *** samples of plutonium oxide were measured under identical conditions using the FH-NCM/S1 in shift register analysis mode and a plutonium waste multiplicity *** obtained double rates underwent corrections for detection efficiency(ε)and double gate fraction(f_(d)),resulting in corrected double rates(D_(c)),which were used to validate the accuracy of the shift register analysis ***,the device exhibited fluctuations in the measurement results,and within a single 20 s measurement,these fluctuations remained below 10%.After 30 cycles,the relative error in the mass of^(240)Pu was less than 5%.Finally,correlation calculations confirmed the robust consistency of both measurement *** study holds specific significance for the subsequent design and development of neutron multiplicity devices.

关键词： Spent fuel Non-destructive assay Neutron multiplicity ^(240)Pu FPGA

Inter-layer interference for multi-layered tight gas reservoir in the absence and presence of movable water

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Petroleum Science 2024年第3期21卷 1751-1764页

作者： tao zhang bin-rui Wang Yu-Long Zhao Lie-Hui zhang Xiang-Yang Qiao Lei zhang jing-jing Guo Hung Vo Thanh National Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu60500SichuanChina Shaanxi Yanchang Petroleum(Group)Corp.Ltd. Xian710075ShaanxiChina Waseda Research Institute for Science and Engineering Waseda UniversityTokyoJapan

Due to the dissimilarity among different producing layers,the influences of inter-layer interference on the production performance of a multi-layer gas reservoir are ***,systematic studies of inter-layer interference for tight gas reservoirs are really limited,especially for those reservoirs in the presence of *** this work,five types of possible inter-layer interferences,including both absence and presence of water,are identified for commingled production of tight gas ***,a series of reservoir-scale and pore-scale numerical simulations are conducted to quantify the degree of influence of each type of *** field evidence from the Yan'an tight gas reservoir(Ordos Basin,China)is found to support the simulation ***,suggestions are proposed to mitigate the potential inter-layer *** results indicate that,in the absence of water,commingled production is favorable in two situations:when there is a difference in physical properties and when there is a difference in the pressure system of each *** reservoirs with a multi-pressure system,the backflow phenomenon,which significantly influences the production performance,only occurs under extreme conditions(such as very low production rates or well shut-in periods).When water is introduced into the multi-layer system,inter-layer interference becomes nearly *** both the gas-rich layer and water-rich layer for commingled production is not desirable,as it can trigger water invasion from the water-rich layer into the gas-rich *** gas-rich layer might also be interfered with by water from the neighboring unperforated water-rich layer,where the water might break the barrier(eg weak joint surface,cement in fractures)between the two layers and migrate into the gas-rich ***,the gas-rich layer could possibly be interfered with by water that accumulates at the bottom of the wellbore due to gravitational diff

关键词： Tight gas Comingled production Interference Two-phase flow Water blocking

Decreased Nrf2 protein level and low sperm quality in intractable spermatocystitis

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Asian Journal of Andrology 2024年第2期26卷 189-194页

作者： shi-Ze Wang Jian-Nan Liu Fen-Fang Zhou Ye-jin-Peng Wang Peng zhang song-tao Cheng Department of Urology Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072China Department of Urology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Health Management and Clinical Medicine School of Medicine and HealthWuhan PolytechnicUniversityWuhan 430071China

To investigate the molecular etiology of low sperm quality in patients with intractable spermatocystitis,spermatozoa samples from patients with persistent hematospermia undergoing transurethral seminal vesiculoscopy and healthy volunteers were *** samples were collected from the seminal vesicles through transurethral seminal vesiculoscopy or by masturbation *** quality was analyzed by a WLJY-9000 color semen analysis *** of tumor necrosis factor alpha(TNFa)and interleukin-6(IL-6)in the seminal plasma was performed using enzyme-linked immunosorbent assay(ELISA).Measurement of H_(2)O_(2)in the seminal plasma was performed with a hydrogen peroxide *** protein levels of nuclear factor erythroid 2-related factor 2(Nrf2)and phosphorylated-Nrf2(p-Nrf2)were measured by western blot analysis and immunofluorescence *** sperm quality parameters and increased levels of inflammatory cytokines(TNFa,IL-6,and H_(2)O_(2))in the seminal plasma were detected among the semen samples from the patients with persistent ***2 and p-Nrf2 were strongly expressed in the nucleus and periphery of human sperm cells,according to the results of the immunofluorescence *** protein levels of Nrf2 and p-Nrf2 were significantly lower in the spermatozoa samples from patients with persistent hematospermia than in those from healthy volunteers with normal sperm *** results suggested that Nrf2 signaling might play a role in the low sperm quality of patients with intractable spermatocystitis.

关键词： H_(2)O_(2) Nrf2 sperm quality spermatocystitis