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Novel multi-waypoint planning methods based on intermediate state optimization

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Science China Technological Sciences 2025年第3期68卷 183-195页

作者： Xinyu QIN Guangbao ZHAO Zixuan LIAO Chao LIU Zhenhua XIONG state key laboratory of Mechanical system and Vibration School of Mechanical Engineering Shanghai Jiao Tong University

Multi-waypoint planning is essential for manipulators to execute complex tasks efficiently. It requires the manipulator to swiftly traverse designated waypoints while adhering to all the kinematic constraints. However, previous research has not fully exploited the kinematic capabilities of manipulators and has overlooked collision considerations. To address these problems, this paper presents two novel methods called recursive intermediate state optimization(RISO) and overall intermediate state optimization(OISO). RISO decomposes the multi-waypoint planning problem into a sequence of one-waypoint planning tasks, employing a recursive approach to generate feasible solutions efficiently. OISO utilizes an improved whale optimization algorithm(WOA), incorporating multiple iterative processes to perform secondary optimization in high-dimensional space based on the initial value, yielding better solutions. The proposed methods have been validated on a six-degree-of-freedom manipulator platform and compared with several traditional algorithms, as well as the state-of-the-art algorithm, Ruckig. The results show that RISO outperforms Ruckig in scenarios where computation time is critical, while OISO is better suited for scenarios where trajectory quality is prioritized over time. Furthermore, the proposed methods can also handle collisions, ensuring the generation of collision-free trajectories.

关键词： multi-waypoint planning intermediate state optimization aerial photography task

Experimental demonstration of 220-GHz terahertz signals wireless transmission over 4.6 km

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Science China(Information Sciences) 2025年第1期68卷 386-388页

作者： Yi WEI Jianjun YU Mingxu WANG Xiongwei YANG Qiutong ZHANG Jingwen TAN Bing ZHANG Ying WU Yang HAN Peng TIAN Wen ZHOU Kaihui WANG Feng ZHAO state key laboratory of ASIC and system Key Laboratory for Information Science of Electromagnetic Waves (MoE)School of Information Science and Technology Fudan University School of Electronic Engineering Xi'an University of Posts and Telecommunications

The advancement of terahertz (THz) communication technology drives the evolution of wireless communication systems,offering novel pathways and technical means for the development of future 6G communication *** wireless communication systems are often constrained by bandwidth limitations of electronic devices in high frequency ***,THz communication technology leverages the characteristics of electromagnetic waves to transcend these limitations,enabling communication athigher frequencies and wider bandwidths.

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Distributed Observer for Full-Measured Nonlinear systems Based on Knowledge of FMCF

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 69-85页

作者： Haotian Xu Shuai Liu Yueyang Li Ke Li the School of Control Science and Engineering Shandong University and also with Key Laboratory of Machine Intelligence and System Control Ministry of Education IEEE the School of electrical Engineering University of Jinan

Driven by practical applications, the achievement of distributed observers for nonlinear systems has emerged as a crucial advancement in recent years. However, existing theoretical advancements face certain limitations: They either fail to address more complex nonlinear phenomena, rely on hard-to-verify assumptions, or encounter difficulties in solving system ***, this paper aims to address these challenges by investigating distributed observers for nonlinear systems through the full-measured canonical form(FMCF), which is inspired by full-measured system(FMS) theory. To begin with, this study addresses the fact that the FMCF can only be obtained through the observable canonical form(OCF) in existing FMS *** paper demonstrates that a class of nonlinear systems can directly obtain FMCF through state space equations, independent of OCF. Also, a general method for solving FMCF in such systems is provided. Furthermore, based on the FMCF, A distributed observer is developed for nonlinear systems under two scenarios: Lipschitz conditions and open-loop bounded *** paper establishes their asymptotic omniscience and demonstrates that the designed distributed observer in this study has fewer design parameters and is more convenient to construct than existing approaches. Finally, the effectiveness of the proposed methods is validated through simulation results on Van der Pol oscillators and microgrid systems.

关键词： Distributed observer full-actuated system full-measured system (FMS) nonlinear observer sensor networks

A real-time multi-head mixed attention mechanism-based prediction method for tunnel boring machine disc cutter wear

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Science China(Technological Sciences) 2025年第1期68卷 286-307页

作者： Haodi WANG Chengjin QIN Honggan YU Zhinan ZHANG Guoqiang HUANG Zhengyang LIU Chengliang LIU state key laboratory of Mechanical system and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In the process of hard rock tunnel excavation,workers often need to enter the tunnel boring machine(TBM)cutterhead at regular intervals to measure cutter ***,this method is time-consuming and *** cutter prediction models primarily rely on geological parameters to predict overall cutter wear before construction,making it challenging to monitor real-time wear at different locations of the cutter and obtain accurate geological *** address these challenges,this paper proposes a multi-head mixed attention mechanism-based method for real-time wear prediction of TBM disc ***,a method of cutter wear normalization to eliminate measurement noise is ***,considering the complex correlation of TBM operating parameters in feature and time dimensions,a new multi-head mixed attention mechanism model is designed to establish the dependency between different features and different moments,to better establish the mapping model between operating parameters and cutter ***,the current cutter wear state can be calculated by accumulating the wear amount of all previous small excavation *** effectiveness of the method is verified by using field data from the Mumbai *** results demonstrate that the method is capable of real-time prediction of front cutter and edge cutter wear on the test set,achieving an average accuracy rate of 95.75%.Moreover,the method can update the cutter wear status after every meter of excavation,which has good real-time *** addition,the average accuracy of cutter wear prediction of the proposed method is 11.75%,10.375%,3.875%,3.625%,1.375%,3.125%,2.25%,and 0.75%higher than that of LSTM,CNN,LSTM-CNN,CACNN,SACNN,MMADNN,MTACNN,and *** summary,this approach offers an accurate prediction of cutter wear state while reducing inspection time and costs and has high application value.

关键词： tunnel boring machine cutter wear estimation multi-head mixed attention mechanism real time

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Value Iteration-Based Distributed Adaptive Dynamic Programming for Multi-Player Differential Game With Incomplete Information

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 436-447页

作者： Yun Zhang Yuqi Wang Yunze Cai the Department of Automation Shanghai Jiao Tong University the key laboratory of system Control and Information Processing Ministry of Education of China the National key laboratory of Air-based Information Perception and Fusion

In this paper, a distributed adaptive dynamic programming(ADP) framework based on value iteration is proposed for multi-player differential games. In the game setting,players have no access to the information of others' system parameters or control laws. Each player adopts an on-policy value iteration algorithm as the basic learning framework. To deal with the incomplete information structure, players collect a period of system trajectory data to compensate for the lack of information. The policy updating step is implemented by a nonlinear optimization problem aiming to search for the proximal admissible policy. Theoretical analysis shows that by adopting proximal policy searching rules, the approximated policies can converge to a neighborhood of equilibrium policies. The efficacy of our method is illustrated by three examples, which also demonstrate that the proposed method can accelerate the learning process compared with the centralized learning framework.

关键词： Distributed adaptive dynamic programming incomplete information multi-player differential game (MPDG) value iteration

Decentralized fault diagnosis of discrete-event systems with unreliable sensors using linear temporal logic

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Science China(Information Sciences) 2025年第1期68卷 322-341页

作者： Weijie DONG Shaoyuan LI Xiang YIN key laboratory of system Control and Information Processing Ministry of EducationDepartment of Automation Shanghai Jiao Tong University

In this paper,we investigate a decentralized diagnosis problem of a discrete-evnt system(DES) subject to unreliable sensors,where the sensor observations of local diagnosers may be non-deterministic as a result of possible *** studies on decentralized robust diagnosis can only deal with different types of sensor failures separately,e.g.,all sensors suffer from the same type of sensor failures such as intermittent sensor failures or permanent sensor ***,since sensors of different local diagnosers may face different external environments and have different internal characteristics,sensors corresponding to different local diagnosers may also have their own fault *** this paper,we propose a flexible framework of decentralized diagnosis for DES subject to unreliable sensors such that sensors of different local diagnosers are permitted to have different types of sensor *** this end,we extend the existing decentralized diagnosis framework to the case where there exist common sensors broadcasting their observations to all local *** apply linear temporal logic(LTL) to constrain infinite behaviors of private sensors of local diagnosers and common ***,a new notion of φ-codiagnosability is proposed as the necessary and sufficient condition for the existence of a decentralized diagnoser that works correctly under sensors,satisfying LTL-based sensor ***,we provide an effective approach to verify the φ-codiagnosability.

关键词： discrete event systems decentralized diagnosis codiagnosability automata

Polypropylene-based blend with enhanced breakdown strength under gamma-ray irradiation for cable insulation

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Nuclear Science and Techniques 2025年第1期36卷 35-48页

作者： Bai-Xin Liu Yu Gao Jing Li Chen-Yi Guo Bo-Sen Si Jun-Guo Gao Yu Chen Bo-Xue Du School of electrical and Information Engineering Tianjin UniversityTianjin 300072China key laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China state key laboratory of electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an 710049China

This study focuses on the electrical properties and microstructure of polypropylene(PP)-based blends used for cable insulation in nuclear power plants(NPPs).The PP-based blend,comprising isotactic PP and propylene-based elastomer(PBE)at concentrations ranging from 0 to 50 wt%,underwent a melt blending process and subsequent cobalt-60 gamma-ray irradiation with doses ranging from 0 to 250 *** conductivity,trap distribution,and alternating(AC)breakdown strength were chosen to assess the insulation *** results indicate that the addition of PBE significantly improves the electrical properties of PP under *** PP,the electrical conductivity increased with irradiation,whereas the trap depth and breakdown strength decreased ***,for the blend,these changes initially exhibit opposite *** the irradiation was increased to 250 kGy,the AC breakdown strength of the blend improved by more than 21%compared to that of *** physical and chemical structures of the samples were investigated to explore the improvement *** results offer insights into the design of new cable-insulation materials suitable for NPPs.

关键词： Nuclear power plant Cable insulation Polypropylene electrical properties Gamma-ray irradiation

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The effects of 17β-trenbolone and bisphenol A on sexual behavior and social dominance via the hypothalamic-pituitary-gonadal axis in male mice

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Journal of Environmental Sciences 2025年第5期151卷 54-67页

作者： Xiang Zuo Minghe Sun Huijuan Bai Shuhui Zhang Jialu Luan Qian Yu Zhenhua Fu Qili Zhao Mingzhu Sun Xin Zhao Xizeng Feng College of Life Science State Key Laboratory of Medicinal Chemical BiologyThe Key Laboratory of Bioactive MaterialsMinistry of EducationNankai UniversityTianjin 300071China Institute of Robotics&Automatic Information system College of Artificial IntelligenceNankai UniversityTianjin 300071China

17β-Trenbolone(17-TB)is well documented as an environmental endocrine disruptor in aquatic biological studies,but its effects on mammals remain poorly ***,17-TB acts as a hormone with properties similar to testosterone,and the consequences of juvenile exposure on adult social behavior remain *** A(BPA)acts as an estrogen-like hormone,compared to ***-week-old male Balb/c mice were exposed orally to 17-TB(100μg/(kg·day))and BPA(4 mg/(kg·day))for 28 *** of social interactions and a three-chamber test showed that 17-TB increased virility in male mice,intensified both male and female sexual behavior,and attracted and accepted female *** also increased social dominance through tube tests inmalemice and markedly activated the c-Fos^(+)immune response in themedial prefrontal cortex(mPFC)and basal amygdala(BLA).ELISA data showed that 17-TB and BPA exposure significantly affected serum gonadotropin-releasing hormone(GnRH),growth hormone(GH),estradiol(E2),and luteinizing hormone(LH)levels,as well as testicular lesions and androgen receptor(ARβ)and estrogen receptor(ERα)*** transcriptomic analysis further confirmed that could disrupt steroid synthesis and linoleic acid-related biometabolic *** findings suggest the influence of 17-TB and BPA exposure on sexual behavior and fertility in male mice,possibly through modulation of the hypothalamic-pituitary-gonadal *** study provides insights relevant to human reproductive health and neuro-social behavioral research,and the potential risk of environmental disturbances should not be overlooked.

关键词： 17β-Trenbolone(17-TB) Bisphenol A(BPA) hypothalamic-pituitary-gonadal axis(HPG) Sex hormones Social dominance Sexual behavior

Gradient maturation experiment on hairs implies taphonomic changes in fossil hairs

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Science China Earth Sciences 2025年第1期68卷 62-73页

作者： Xin LI Yibo ZHOU Tao ZHAO Xingjian HE Yanhong PAN state key laboratory for Mineral Deposits Research Center for Critical Earth Material CyclingCentre for Research and Education on Biological Evolution and Environment and Frontiers ScienceSchool of Earth Sciences and EngineeringNanjing UniversityNanjing210023China Institute of Palaeontology Yunnan Key Laboratory of Earth System ScienceYunnan Key Laboratory for PalaeobiologyYunnan UniversityKunming650500China

Mammalian hair,as a key feature related to endothermy,physical protection,and camouflage,has a long geohistorical record that dates back even to the ***,the limited information on the taphonomy of hair hinders the understanding of its evolutionary significance in deep *** address this,we conducted taphonomic experiments to simulate the transformation process of black *** changes in the morphological structure,microscopic characteristics,and chemical composition of hair during the simulated fossilization process were documented by scanning electron microscopy,Fourier transform infrared(FTIR)spectroscopy,and Raman *** results revealed that damage to the morphology of hair began at a mild temperature(150–175℃),and hair transformed into a fluid-like mass at a relatively high temperature(200℃).In addition,the morphological structure of melanosomes had relatively greater preservation potential than keratins did,and the microscopic features of melanosomes were persistently *** Raman and FTIR spectra indicated that the characteristic melanin and keratin peaks changed as the temperature *** the chemical signals were not lost completely,the variations in the characteristic amide bands in the FTIR spectra indicate that the keratins severely degraded at high temperatures(>200℃),whereas the characteristic melanin bands in the Raman spectra suggested that melanin signals were still recognizable,even at high temperatures(>200℃).These results were confirmed by principal component analysis(PCA)and principal component analysis linear discriminant analysis(PCA–LDA).In addition,the Raman signals of all the samples in the simulated experiments were distinguished from the signals of common geological carbonaceous materials(humic acid),which suggested that Raman spectroscopy can be used to detect melanin in fossils.

关键词： Mammalian hair Melanin Keratin Fossilization Experimental taphonomy

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