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Communication-robust multi-agent learning by adaptable auxiliary multi-agent adversary generation

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Frontiers of Computer Science 2024年第6期18卷 186331-186331页

作者： yuAN lei CHEN feng ZHANG Zongzhang yu Yang National Key Laboratory for Novel Software Technology Nanjing University Polixir Technologies

Communication can promote coordination in cooperative Multi-Agent Reinforcement Learning (MARL). Nowadays, existing works mainly focus on improving the communication efficiency of agents, neglecting that real-world communication is much more challenging as there may exist noise or potential attackers. Thus the robustness of the communication-based policies becomes an emergent and severe issue that needs more exploration. In this paper, we posit that the ego system trained with auxiliary adversaries may handle this limitation and propose an adaptable method of Multi-Agent Auxiliary Adversaries Generation for robust Communication, dubbed MA3C, to obtain a robust communication-based policy. In specific, we introduce a novel message-attacking approach that models the learning of the auxiliary attacker as a cooperative problem under a shared goal to minimize the coordination ability of the ego system, with which every information channel may suffer from distinct message attacks. Furthermore, as naive adversarial training may impede the generalization ability of the ego system, we design an attacker population generation approach based on evolutionary learning. Finally, the ego system is paired with an attacker population and then alternatively trained against the continuously evolving attackers to improve its robustness, meaning that both the ego system and the attackers are adaptable. Extensive experiments on multiple benchmarks indicate that our proposed MA3C provides comparable or better robustness and generalization ability than other baselines.

关键词： multi-agent communication adversarial training robustness validation reinforcement learning

Experimental study on detonation parameters and cellular structures of fuel cloud

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Acta Mechanica Sinica 2012年第2期28卷 438-443页

作者： Li-feng Xie Bin Li yu-lei Zhang School of Chemical Engineering Nanjing University of Science and Technology210094 NanjingChina

In this paper, detonation parameters of fuel cloud, such as propylene oxide （PO）, isopropyl nitrate （IPN）, hex- ane, 90# oil and decane were measured in a self-designed and constructed vertical shock tube. Results show that the deto- nation pressure and velocity of PO increase to a peak value and then decrease smoothly with increasing equivalence ra- tio. Several nitrate sensitizers were added into PO to make fuel mixtures, and test results indicated that the additives can efficiently enhance detonation velocity and pressure of fuel cloud and one type of additive n-propyl nitrate （NPN） played the best in the improvement. The critical initiation energy that directly initiated detonation of all the test liquid fuel clouds showed a U-shape curve relationship with equiva- lence ratios. The optimum concentration lies on the rich-fuel side （;b 〉 1）. The critical initiation energy is closely related to molecular structure and volatility of fuels. IPN and PO have similar critical values while that of alkanes are larger. Detonation cell sizes of PO were respectively investigated at 25;C, 35;C and 50;C with smoked foil technique. The cell width shows a U-shape curve relationship with equivalence ratios at all temperatures. The minimal cell width also lies on the rich-fuel side （;b 〉 1）. The cell width of PO vapor is slightly larger than that of PO cloud. Therefore, the deto- nation reaction of PO at normal temperature is controlled by gas phase reaction.

关键词： Cloud detonation Detonation velocity Deto- nation pressure - Critical initiation energy Cell size

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen yu Han Jun Wang Shibo Xi yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Activation energy

胸腔镜手术治疗肋骨骨纤维异常增殖症的可行性研究(附15例报告)

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中国内镜杂志 2022年第2期28卷 82-85页

作者：黄奇谭思创胡衍王彬喻风雷中南大学湘雅二医院胸外科湖南长沙410005

目的探讨胸腔镜微创手术治疗肋骨骨纤维异常增殖症的安全性、疗效及优势。方法回顾性分析2013年2月-2020年8月中南大学湘雅二医院胸外科收治的15例肋骨骨纤维异常增殖症患者的临床资料,患者均采用胸腔镜微创手术方法治疗。其中,男7例,女... 详细信息

目的探讨胸腔镜微创手术治疗肋骨骨纤维异常增殖症的安全性、疗效及优势。方法回顾性分析2013年2月-2020年8月中南大学湘雅二医院胸外科收治的15例肋骨骨纤维异常增殖症患者的临床资料,患者均采用胸腔镜微创手术方法治疗。其中,男7例,女8例,年龄16~52岁,平均(36.7±12.6)岁。病变位于左侧6例,右侧9例;共17根肋骨发生病变,位于第4肋1例,第5肋5例,第6肋5例,第7肋3例,第8肋2例,第9肋1例。无合并奥尔布赖特综合征患者。手术均由同一组高年资医师完成。采用胸腔镜单操作孔进行手术(2孔,一孔为观察孔,一孔为操作孔),胸腔镜下定位病变肋骨,在胸腔内操作切除。结果15例患者均顺利完成手术。手术时间45~72 min,平均(61.0±10.5)min。术后病理均为肋骨骨纤维异常增殖症。术后住院时间3~5 d,平均(3.0±1.0)d。术后疼痛评分1~5分,平均(3.3±1.2)分。术中术后无严重并发症。术后随访12~36个月,平均(24.5±6.2)个月,所有患者未见复发。结论胸腔镜手术治疗肋骨骨纤维异常增殖症安全、可靠,创伤小,疗效满意,值得推广应用。

关键词：胸腔镜肋骨切除术肋骨骨纤维异常增殖症肋骨病变

New glucocerebrosidase antibodies can advance research in the field of neurodegenerative disorders

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Neural Regeneration Research 2025年第4期20卷 1085-1086页

作者： Charis Ma Krystyna Rytel yu Chen Ellen Sidransky Medical Genetics Branch National Human Genome Research InstituteNational Institutes of HealthBethesdaMDUSA

In medical research,there are times when the introduction of a new tool can launch scientific discovery in new *** antibody development may be considered mundane,in the field of glucocerebrosidase(GCase)research,the dearth of validated antibodies for different applications has impeded progress in studies of disease pathogenesis and therapeutic *** recent introduction of new,rigorously evaluated antibodies can now propel research into the link between glucocerebrosidase and Parkinson’s disease(PD)as well as aspects of the pathobiology of Gaucher disease(Jong et al.,2024).

关键词： antibodies cerebro

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping yu Emily Choi Michael QJiang Ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Application of split Hopkinson tension bar technique to the study of dynamic fracture properties of materials

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Acta Mechanica Sinica 2012年第2期28卷 424-431页

作者： Ze-Jian Xu yu-Long Li feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology100081 BeijingChina School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

A novel approach is proposed in determining dy- namic fracture toughness （DFT） of high strength steel, using the split Hopkinson tension bar （SHTB） apparatus, com- bined with a hybrid experimental-numerical method. The center-cracked tension specimen is connected between the bars with a specially designed fixture device. The fracture initiation time is measured by the strain gage method, and dynamic stress intensity factors （DSIF） are obtained with the aid of 3D finite element analysis （FEA）. In this approach, the dimensions of the specimen are not restricted by the connec- tion strength or the stress-state equilibrium conditions, and hence plane strain state can be attained conveniently at the crack tip. Through comparison between the obtained results and those in open publication, it is concluded that the ex- perimental data are valid, and the method proposed here is reliable. The validity of the obtained DFT is checked with the ASTM criteria, and fracture surfaces are examined at the end of paper.

关键词： Split Hopkinson tension bar Dynamic fracture toughness Hybrid experimental-numerical method High loading rate Failure mode

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping CHENG Jian WEI Chao yuAN Bin yu Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

Modification of SDOF model for reinforced concrete beams under close-in explosion

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Defence Technology（防务技术） 2023年第2期20卷 162-186页

作者： Wei Wei yu-lei Zhang Jian-jun Su Yan Liu feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Xi'an Modern Chemistry Research Institute Xi'an710065China

In this paper,a modified single-degree-of-freedom(SDOF)model of reinforced concrete(RC)beams under close-in explosion is proposed by developing the specific impulse equivalent method and flexural resistance calculation *** equivalent uniform specific impulse was obtained based on the local conservation of momentum and global conservation of kinetic ***,the influence of load uniformity,boundary condition and complex material behaviors(*** rate effect,hardening/softening and hoop-confined effect)was considered in the resistance calculation process by establishing a novel relationship between external force,bending moment,curvature and deflection *** accuracy of the proposed model was verified by carrying out field explosion tests on four RC beams with the scaled distances of 0.5 m/kg~(1/3)and 0.75 m/kg~(1/3).The test data in other literatures were also used for *** a result,the equivalent load implies that the blast load near the mid-span of beams would contribute more to the maximum displacement,which was also observed in the ***,both the resistance model and test results declare that when the blast load becomes more concentrated,the ultimate resistance would become lower,and the compressive concrete would be more prone to softening and ***,based on the modified SDOF model,the calculated maximum displacements agreed well with the test data in this paper and other *** work fully proves the rationality of the modified SDOF method,which will contribute to a more accurate damage assessment of RC structures under close-in explosion.

关键词： SDOF model Close-in explosion Specific impulse equivalent method Flexural resistance