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Chinese Journal of Aeronautics 2024年第2期37卷 471-481页

作者： li WANG jiang li Kang li Yiwei WANG Chenyang MA Science and Technology on Combustion Internal Flow and Thermal-Structure LaboratoryNorthwestern Polytechnical UniversityXi’an 710072China

Carbon Nanotubes(CNTs)reinforced Polymer-Matrix Composites(PMCs)is widely used as insulation materials in thermal protection system of aerospace ***,CNTs are prone to oxidation and have high thermal conductivities,which makes it difficult to improve the ablation resistance of insulation materials that contain ***_(2)was encapsulated onto the surface of CNTs(CNTs@SiO_(2)),which were then added to Ethylene Propylene Diene Monomer(EPDM)rubber to prepare the insulation *** analysis and ablation test were used to evaluate the resistance of the insulation materials to thermal oxidation and ***,scanning electron microscopy was performed to analyze their *** revealed that the addition of CNTs@SiO_(2)could visibly reduce the effects of hot corrosion and ablation on insulation *** C-CNTs@SiO_(2)-1 formulation had the best ablative ***,compared with the unencapsulated formulation(C-CNTs-10),the C-CNTs@SiO_(2)-1 formulation reduced the line ablation rate by 51%to 0.0130 mm/s after oxygen-acetylene ***,the ablation mechanism was investigated based on the effects of the CNTs@SiO_(2)additive on their ***,the improvement in ablation performance may be attributed to CNTs@SiO_(2)-induced decreases in thermal conductivity,improvement in the hot corrosion resistance in the char layer,and changes in the microstructure.

关键词： Polymer-Matrix Composites(PMCs) Carbon Nanotubes(CNTs) Thermal properties Ablation Oxidation

A New Solution to Intrusion Detection Systems Based on Improved Federated-Learning Chain

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Computers, Materials & Continua 2024年第6期79卷 4491-4512页

作者： Chunhui li Hua jiang School of Computer and Electronic Information Guangxi UniversityNanning530000China Cyber Security and Information Center Guangxi UniversityNanning530000China

In the context of enterprise systems,intrusion detection(ID)emerges as a critical element driving the digital transformation of *** systems spanning various sectors of enterprises geographically dispersed,the necessity for seamless information exchange has surged *** existing cross-domain solutions are challenged by such issues as insufficient security,high communication overhead,and a lack of effective update mechanisms,rendering them less feasible for prolonged application on resource-limited *** study proposes a new cross-domain collaboration scheme based on federated chains to streamline the server-side *** this framework,individual nodes solely engage in training local data and subsequently amalgamate the final model employing a federated learning algorithm to uphold enterprise systems with efficiency and *** curtail the resource utilization of blockchains and deter malicious nodes,a node administration module predicated on the workload paradigm is introduced,enabling the release of surplus resources in response to variations in a node’s contribution *** encountering an intrusion,the system triggers an alert and logs the characteristics of the breach,facilitating a comprehensive global update across all nodes for collective *** results across multiple scenarios have verified the security and effectiveness of the proposed solution,with no loss of its recognition accuracy.

关键词： Cross-domain collaboration blockchain federated learning contribution value node management release slack resources

Synergistic mechanisms of AMF and biochar driving rhizosphere fungal community in shallot in barren soil

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Horticultural Plant Journal 2024年第5期10卷 1252-1256页

作者： Zishan li Yingyue li Qing Zhang Zihua Zhang Jiaqing jiang Tao Huang Chunge mei Fulang Wu Beijiu Cheng Xiaoyu li Jin Chen National Engineering Laboratory of Crop Stress Resistance Breeding Schools of Life SciencesAnhui Agricultural UniversityHefeiAnhui 230036China

The addition of biochar(BC)or Arbuscular mycorrhizal fungi(AMF)alone has been reported to promote plant growth,while their synergistic effects on Allium schoenoprasum root morphology and rhizosphere fungal community in barren soil is still *** this study,we investigated the effects of BC and AMF(Funneliformis mosseae)on plant growth and root morphology in barren soil and revealed the structure of soil fungal communities Therefore,a greenhouse pot trial consisting of five treatments was *** results showed that the combination of biochar and AMF significantly improved plant biomass,nutrient uptake,mycorrhizal colonization rates and soil properties and significantly impacted rhizosphere fungal community composition and *** significantly increased the fungal community stability and enhanced their positive correlation with *** findings indicated that the combination of AMF and biochar play synergic role for plant growth and rhizosphere fungal community in barren soil.

关键词： soil rhizosphere barren

Risk Constrained Self-scheduling of AA-CAES Facilities in Electricity and Heat Markets:A Distributionally Robust Optimization Approach

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1159-1167页

作者： Zhiao li Laijun Chen Wei Wei Shengwei mei Department of Electrical Engineering Tsinghua UniversityBeijing 100084China New Energy(Photovoltaic)Industry Research Center Qinghai UniversityXining 810016China IEEE

Advanced adiabatic compressed air energy storage(AA-CAES)has the advantages of large capacity,long service time,combined heat and power generation(CHP),and does not consume fossil fuels,making it a promising storage technology in a low-carbon *** appropriate self-scheduling model can guarantee AA-CAES’s profit and attract ***,very few studies refer to the cogeneration ability of AA-CAES,which enables the possibility to trade in the electricity and heat markets at the same *** this paper,we propose a multimarket self-scheduling model to make full use of heat produced in *** volatile market price is modeled by a set of inexact distributions based on historical data through-***,the self-scheduling model is cast as a robust risk constrained program by introducing Stackelberg game theory,and equivalently reformulated as a mixed-integer linear program(MILP).The numerical simulation results validate the proposed method and demonstrate that participating in multienergy markets increases overall *** impact of uncertainty parameters is also discussed in the sensibility analysis.

关键词： Advanced adiabatic compressed air energy storage(AA-CAES) conditional value at risk(CVaR) distributionally robust optimization(DRO) heat market self-scheduling Stackelberg game

Spectrum analysis of interval process model and its application in uncertain vibration analysis

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Science China(Technological Sciences) 2024年第8期67卷 2549-2564页

作者： li JinWu jiang Chao NI BingYu State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

In recent years, the authors have extended the traditional interval method into the time dimension to develop a new mathematical tool called the “interval process model” for quantifying time-varying or dynamic uncertainties. This model employs upper and lower bounds instead of precise probability distributions to quantify uncertainty in a parameter at any given time point. It is anticipated to complement the conventional stochastic process model in the coming years owing to its relatively low dependence on experimental samples and ease of understanding for engineers. Building on our previous work, this paper proposes a spectrum analysis method to describe the frequency domain characteristics of an interval process, further strengthening the theoretical foundation of the interval process model and enhancing its applicability for complex engineering problems. In this approach, we first define the zero midpoint function interval process and its auto/cross-power spectral density(PSD) functions. We also deduce the relationship between the auto-PSD function and the auto-covariance function of the stationary zero midpoint function interval process. Next, the auto/cross-PSD function matrices of a general interval process are defined, followed by the introduction of the concepts of PSD function matrix and cross-PSD function matrix for interval process vectors. The spectrum analysis method is then applied to random vibration problems, leading to the creation of a spectrum-analysis-based interval vibration analysis method that determines the PSD function for the system displacement response under stationary interval process excitations. Finally, the effectiveness of the formulated spectrum-analysis-based interval vibration analysis approach is verified through two numerical examples.

关键词： interval process spectrum analysis power spectral density(PSD) time-varying uncertainty uncertain vibration analysis

Source apportionment of PM_(2.5)using PMF combined online bulk and single-particle measurements:Contribution of fireworks and biomass burning

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Journal of Environmental Sciences 2024年第2期136卷 325-336页

作者： Yanjing Zhang Wenshuai li Lei li mei li Zhen Zhou Jianzhen Yu Yang Zhou Frontier Science Center for Deep Ocean Multispheres and Earth System(FDOMES)and Physical Oceanography Laboratory Ocean University of ChinaQingdaoShandong 266100China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdaoShandong 266100China Institute of Atmospheric Environment Safety and Pollution Control Jinan UniversityGuangdong 510632China Institute of Environment Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Department of Chemistry Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina Division of Environment The Hong Kong University of Science and TechnologyClear Water BayKowloonHong KongChina

Fireworks(FW)could significantly worsen air quality in short term during *** to similar tracers with biomass burning(BB),the fast and precise qualification of FW and BB is still *** this study,online bulk and single-particle measurements were combined to investigate the contributions of FW and BB to the overall mass concentrations of PM_(2.5)and specific chemical species by positive matrix factorization(PMF)during the Chinese New Year in Hong Kong in February *** combined information,fresh/aged FW(abundant ^(140)K_(2)NO_(3)^(+)and ^(213)K_(3)SO_(4)^(+)formed from ^(113)K_(2)Cl^(+)discharged by fresh FW)can be extracted from the fresh/aged BB sources,in addition to the Second Aerosol,Vehicles+Road Dust,and Sea Salt *** contributions of FW and BB were investigated during three high particle matter episodes influenced by the pollution transported from the Pearl River Delta *** fresh BB/FW contributed 39.2%and 19.6%to PM_(2.5)during the Lunar Chinese New Year ***,the contributions of aged FW/BB enhanced in the last two episodes due to the aging process,evidenced by high contributions from secondary ***,the fresh BB/FW showed more significant contributions to nitrate(35.1%and15.0%,respectively)compared with sulfate(25.1%and 5.9%,respectively)and OC(14.8%and11.1%,respectively)on *** comparison,the aged FW contributed more to sulfate(13.4%).Overall,combining online bulk and single-particle measurement data can combine both instruments’advantages and provide a new perspective for applying source apportionment of aerosols using PMF.

关键词： Source apportionment PMF Online bulk measurements Single particle analysis Fireworks Biomass burning

Serum tumor markers expression(CA199,CA242,and CEA)and its clinical implications in type 2 diabetes mellitus

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World Journal of Diabetes 2024年第2期15卷 232-239页

作者： mei Meng li-li Shi Department of Endocrinology Hefei BOE HospitalHefei 230013Anhui ProvinceChina Department of Cadre Ward The First Affiliated Hospital of Harbin Medical UniversityHarbin 150001Heilongjiang ProvinceChina

BACKGROUND Glucose and lipid metabolic disorder in patients with type 2 diabetes mellitus(T2DM)is associated with the levels of serum tumor markers of the digestive tract,such as cancer antigen(CA)***,tumor markers in T2DM are *** To evaluate the expression of serum tumor markers[CA199,CA242,and carcinoembryonic antigen(CEA)]and the clinical implications of the expression in *** For this observational study conducted at Hefei BOE Hospital,China,we enrolled 82 patients with first-onset T2DM and 51 controls between April 2019 and December *** of fasting blood glucose(FBG),tumor markers(CA199,CEA,and CA242),glycosylated hemoglobin(HbA1c),*** measured and group index levels were ***,FBG and HbA1c levels were correlated with tumor marker *** markers were tested for diagnostic accuracy in patients with>9%HbA1c using the receiver operating curve(ROC)*** The T2DM group had high serum FBG,HbA1c,CA199,and CEA levels(P9%)revealed significant differences in CEA and CA199 levels(P<0.05).The areas under the ROC curve for CEA and CA199 were 0.853 and 0.809,***199,CEA,and CA242 levels positively correlated with HbA1c(r=0.308,0.426,and 0.551,respectively)and FBG levels(r=0.236,0.231,and 0.298,respectively).CONCLUSION As compared to controls,serum CEA and CA199 levels were higher in patients with ***1c and FBG levels correlated with CA199,CEA,and CA242 *** with poorly controlled blood sugar must be screened for tumor markers.

关键词： Type 2 diabetes mellitus Carcinoembryonic antigen Cancer antigen 199 Cancer antigen 242 Glycosylated hemoglobin

Security of quantum key distribution with virtual mutually unbiased bases

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 13-21页

作者： Hong-Wei li Chen-Peng Hao Zhi-jiang Chen li Gong Yi-Fei Lu Yang Wang Jia-Ji li Chun-mei Zhang Rong Wang Zhen-Qiang Yin Qing-Yu Cai Henan Key Laboratory of Quantum Information and Cryptography SSF IEUZhengzhou 450000China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China Department of Physics University of Hong KongHong Kong 999077China Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China School of Information and Communication Engineering Hainan UniversityHaikou 570228China

In a perfect quantum key distribution(QKD)protocol,quantum states should be prepared and measured with mutually unbiased bases(MUBs).However,in a practical QKD system,quantum states are generally prepared and measured with imperfect MUBs using imperfect devices,possibly reducing the secret key rate and transmission *** analyze the security of a QKD system with imperfect MUBs,we propose virtual MUBs to characterize the quantum channel against collective attack,and analyze the corresponding secret key rate under imperfect state preparation and measurement *** generally,we apply the advantage distillation method for analyzing the security of QKD with imperfect MUBs,where the error tolerance and transmission distance can be sharply *** analysis method can be applied to benchmark and standardize a practical QKD system,elucidating the security analysis of different QKD protocols with imperfect devices.

关键词： quantum key distribution mutually unbiased bases advantage distillation

Characteristics of Bi-2223 HTS Tapes Under Short-Circuit Current Impacts in Hybrid Energy Transmission Pipelines

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 736-745页

作者： Yuguang Sun Chao Yin Weizhen li Xinyang li Xiaohua jiang Department of Electric Engineering Tsinghua UniversityBeijing 100084China

A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.

关键词： Bi-2223 high-temperature superconducting(HTS)tape critical current hybrid energy transmission pipeline liquefied natural gas(LNG)cooling temperature short-circuit current impact characteristics

Experimental investigation about the incipient velocity of spherical particles on a hemispherical bed surface

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Particuology 2024年第5期88卷 49-61页

作者： Chuannan li Jie Chen Changbo jiang Xie li Zhiyuan Wu School of Hydraulic and Environmental Engineering Changsha University of Science & TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province Changsha 410114China

The sediment particles play a huge role in shaping the bed load *** this research,240 water-tunnel experiments are carried out to investigate the incipient velocity of the observation particles in two particle *** accurately predict the incipient velocity of the observation particles,the equation is conceived by the rolling instability *** incipient velocity equations and experimental data are used to analyze the trend of dispersive pressure and the effect of arrangement position on *** find that it is appropriate to choose the coefficient of drag as 0.261 and the coefficient of lift as 0.198 for the incipient velocity equation of spherical particles on the hemispherical bed ***,the dispersive pressure is closely related to the flow state,particle size,and particle arrangement,which leads to the incipient velocity of the observation particle being at a minimum when the interference particle angle is 45°.Finally,the particle spacing and the projected area changed with the arrangements,directly affecting the incipient velocity of the observed *** analysis of four aspects for the coefficients,dispersive pressure,different particle spacing,and projected area will facilitate the prediction of particle incipient velocity,especially on hemispherical beds.

关键词： Hemispherical bed surface Observed particle Interference particle Dispersive pressure Incipient velocity