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An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming Liang Guangning Li Min Xu Junmin Zhao feng hao Hongbo Shi Northwestern Polytechnical University School of Astronautics Xi’an 710072China China North Industries Group Corporation No 203 Research Institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is proposed.The proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application prospect.Firstly,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is constructed.In order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried out.The simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight simulation.Secondly,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy respectively.The intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight parameters.Compared with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability error.The intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid

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Regulation of the quantum barrier and carrier transport toward high-efficiency quasi-2D Dion-Jacobson tin perovskite solar cells

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Journal of Energy Chemistry 2024年第8期95卷 200-207页

作者： Huanhuan Yao Chang Shi Tai Wu Shurong Wang Mingyu Yin Liming Ding Yong Hua feng hao School of Materials and Energy University of Electronic Science and Technology of China College of Chemistry and Molecular Engineering Peking University Yunnan Key Laboratory for Micro/Nano Materials & Technology School of Materials and Energy Yunnan University Center for Excellence in Nanoscience (CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication (CAS) National Center for Nanoscience and Technology

Quasi-2D Dion-Jacobson（DJ） tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental stability.However,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device performance.Here,we designed three organic spacers with different chain lengths(ethylenediamine（EDA）,1,3-propanediamine（PDA）,and 1,4-butanediamine（BDA）) to investigate the quantum barrier dependence.Theoretical and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative relaxation.In addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural stability.Furthermore,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different nphases.Finally,the quasi-2D DJ（EDA）FA9Sn10I31solar cells achieves a 7.07% power conversion efficiency with good environment stability.Therefore,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.

关键词： Carrier transport Chain lengths Lattice distortion Organic spacers Quantum well

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Agronomic performances of biodegradable and non-biodegradable plastic film mulching on a maize cropping system in the semi-arid Loess Plateau,China

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Pedosphere 2024年第1期34卷 88-96页

作者： hao ZHANG Mengqiong CHEN Ruiquan QIAO Fan DING hao feng Rui JIANG Research Center for Cultural Landscape Protection and Ecological Restoration China-Portugal Belt and Road Cooperation Laboratory of Cultural Heritage Conservation ScienceGold Mantis School of ArchitectureSoochow UniversitySuzhou 215006China Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of AgricultureCollege of Natural Resources and EnvironmentNorthwest A&F UniversityYangling 712100China College of Land and Environment Shenyang Agricultural UniversityShenyang 110866China Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100China

Biodegradable plastic film mulch (PFM) is considered an alternative to non-biodegradable PFM to mitigate the negative impacts of residual film.However,the agronomic performance of biodegradable PFM in comparison to non-biodegradable PFM still needs to be tested.In this study,we evaluated the effects of biodegradable and non-biodegradable PFM on soil physicochemical properties,microbial community,and enzyme activities,as well as maize growth performance.Biodegradable and non-biodegradable PFM both increased soil temperature,water content,N content,and microbial biomass and maize yield by up to 30%,but decreased soil enzyme activities as compared to no mulching (control,CK).Most soil physicochemical properties,microbial community,and enzyme activities were similar under non-biodegradable and biodegradable PFM at the early stages of maize growth.However,at the late stages,soil temperature,water content,mineral N,NO_(3)^(-)-N,ammonia monooxygenase (AMO) activity,and total phospholipid fatty acids (PLFAs) decreased under biodegradable PFM owing to film fragmentation.White PFM increased soil temperature,water content,and total PLFAs at the early stages of maize growth but decreased soil mineral N and total PLFAs at the late stages,as compared to black PFM.As soil temperature and N availability were the major factors affecting soil microbial community,microbial activity decreased after the fragmentation of biodegradable PFM,owing to the decreased soil temperature,water content,and mineral N.Notably,biodegradable PFM could decrease NO_(3)^(-)-N accumulation in topsoil by decreasing N transformation due to the lower microbial and N-related enzyme (e.g.,AMO) activities,compared with non-biodegradable PFM,which may avoid negative environmental impacts,such as NO_(3)^(-)-N leaching or gas emission after harvest.Maize yield,height,aboveground biomass,and N uptake under biodegradable PFM were similar to those under non-biodegradable PFM during maize growth,implying that biodegradable PFM has no negative impact on crop growth a

关键词： black plastic film mulching enzyme activity film fragmentation microbial community phospholipid fatty acid white plastic film mulching

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Interaction Mechanisms between Natural Debris Flow and Rigid Barrier Deflectors:A New Perspective for Rational Design and Optimal Arrangement

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1679-1699页

作者： Yu Huang Beilei Liu Dianlei feng hao Shi Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai200092China

Rigid barrier deflectors can effectively prevent overspilling landslides,and can satisfy disaster prevention requirements.However,the mechanisms of interaction between natural granular flow and rigid barrier deflectors require further investigation.To date,few studies have investigated the impact of deflectors on controlling viscous debris flows for geological disaster prevention.To investigate the effect of rigid barrier deflectors on impact mechanisms,a numerical model using the smoothed particle hydrodynamics(SPH)method with the Herschel–Bulkley model is proposed to simulate the interaction between natural viscous flow and single/dual barriers with and without deflectors.This model was validated using laboratory flume test data from the literature.Then,the model was used to investigate the influence of the deflector angle and multi-barrier arrangements.The optimal configuration of multi-barriers was analyzed with consideration to the barrier height and distance between the barriers,because these metrics have a significant impact on the viscous flow pile-up,run-up,and overflow mechanisms.The investigation considered the energy dissipation process,retention efficiency,and dead-zone formation.Compared with bare barriers with similar geometric characteristics and spatial distribution,rigid barriers with deflectors exhibit superior effectiveness in preventing the overflow and overspilling of viscous debris flow.Recommendations for the rational design of deflectors and the optimal arrangement of multi-barriers are provided to mitigate geological disasters.

关键词： Rigid barrier deflectors deflector angle single-barrier dual-barrier arrangements viscous debris flow over-spilling delta-plus-SPH

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The hydrophobic cluster on the surface of protein is the key structural basis for the SDS-resistance of chondroitinase VhChlABC

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Marine Life Science & Technology 2024年第1期6卷 93-101页

作者： Juanjuan Su hao Wu Chengying Yin fengchao Zhang feng Han Wengong Yu School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Qingdao Marine Science and Technology CenterQingdao 266237China Key Laboratory of Marine Drugs Ministry of EducationQingdao 266003China Shandong Provincial Key Laboratory of Glycoscience and Glycoengineering Qingdao 266003China

The application of chondroitinase requires consideration of the complex microenvironment of the target.Our previous research reported a marine-derived sodium dodecyl sulfate(SDS)-resistant chondroitinase VhChlABC.This study further investigated the mechanism of VhChlABC resistance to SDS.Focusing on the hydrophobic cluster on its strong hydrophilic surface,it was found that the reduction of hydrophobicity of surface residues Ala181,Met182,Met183,Ala184,Val185,and Ile305 significantly reduced the SDS resistance and stability.Molecular dynamics(MD)simulation and molecular docking analysis showed that I305G had more conformational flexibility around residue 305 than wild type(WT),which was more conducive to SDS insertion and binding.The affinity of A181G,M182A,M183A,V185A and I305G to SDS was significantly higher than that of WT.In conclusion,the surface hydrophobic microenvironment composed of six residues was the structural basis for SDS resistance.This feature could prevent the binding of SDS and the destruction of hydrophobic packaging by increasing the rigid conformation of protein and reducing the binding force of SDS-protein.The study provides a new idea for the rational design of SDS-resistant proteins and may further promote chondroitinase research in the targeted therapy of lung diseases under the pressure of pulmonary surfactant.

关键词： Hydrophobic cluster Protein surface SDS-resistance Chondroitinase

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Corporate Credit Ratings Based on Hierarchical Heterogeneous Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 257-271页

作者： Bo-Jing feng Xi Cheng hao-Nan Xu Wen-Fang Xue Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China

order to help investors understand the credit status of target corporations and reduce investment risks,the corporate credit rating model has become an important evaluation tool in the financial market.These models are based on statistical learning,machine learning and deep learning especially graph neural networks(GNNs).However,we found that only few models take the hierarchy,heterogeneity or unlabeled data into account in the actual corporate credit rating process.Therefore,we propose a novel framework named hierarchical heterogeneous graph neural networks(HHGNN),which can fully model the hierarchy of corporate features and the heterogeneity of relationships between corporations.In addition,we design an adversarial learning block to make full use of the rich unlabeled samples in the financial data.Extensive experiments conducted on the public-listed corporate rating dataset prove that HHGNN achieves SOTA compared to the baseline methods.

关键词： Corporate credit rating hierarchical relation heterogeneous graph neural networks adversarial learning

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Straw addition increases enzyme activities and microbial carbon metabolism activities in bauxite residue

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Journal of Environmental Sciences 2024年第1期135卷 332-344页

作者： hao Wu Wei Sun feng Zhu Yifan Jiang Shiwei Huang Johnvie Goloran Shengguo Xue School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Environment and Science Griffith UniversityBrisbaneQLD 4072Australia

Recovery of microbial functions is one of the critical processes in the nutrient cycling of bauxite residue for improving revegetation.Straw is considered to be effective to increase microbial diversity and drive the development of the microbial community,but its effect on microbial carbon metabolism has not been illustrated.The present study evaluated the effects of phosphogypsum(PG),straw(SF)and phosphogypsum plus straw(PGSF)on physicochemical properties,enzyme activities,and microbial carbon metabolism activities in bauxite residue.After 180 days incubation,PG,SF and PGSF treatment significantly reduced the residue pH from 10.85 to 8.64,9.39 and 8.06,respectively.Compared to CK treatment,SF treatment significantly increased the content of total organic carbon(TOC)and organic carbon fractions(DOC,MBC,EOC,and POC).In addition,straw addition significantly increased glucosidase,cellulose,urease,and alkaline phosphatase by 7.2-9.1 times,5.8-7.1 times,11.1-12.5 times,and 1.1-2.2 times,respectively.The Biolog results showed that straw addition significantly increased microbial metabolic activity(AWCD)and diversity in bauxite residue.Redundancy analysis indicated total nitrogen(TN)and carbon fractions(POC,MBC and DOC)were the most important environmental factors affecting microbial metabolic activity and diversity in bauxite residue.These findings provided us with a biogeochemical perspective to reveal soil formation in bauxite residue and suggested that nutrient supplement and regulation of salinity-alkalinity benefit the establishment of microbial communities and functions in bauxite residue.

关键词： Bauxite residue Labile organic carbon fractions Enzyme activities Community-level physiological profiles Soil formation in bauxite residue

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Remote copper-catalyzed enantioselective substitution of yne-thiophene carbonates

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Science China Chemistry 2024年第4期67卷 1175-1180页

作者： hao-Dong Qian Xiang Li Tingrui Yin Wei-feng Qian Chunhui Zhao Cuiju Zhu hao Xu CCNU-uOttawa Joint Research Centre Key Laboratory of Pesticides&Chemical Biology of Ministry of EducationInternational Joint Research Center for Intelligent Biosensing Technology and HealthCollege of ChemistryCentral China Normal UniversityWuhan 430079China

Here,we describe a strategy for the copper-catalyzed asymmetric heteroarylation of yne-thiophene carbonates with indoles via remote substitution.The key to the success of this strategy lies in the design of the alkynyl group at the ortho-position of the heterocycle thiophene,enabling the formation of a triarylmethane moiety via very remote substitution.Thus,the concept of remote copper-catalyzed asymmetric transformation extends not only to yne-allylic esters but also to yne-aryl esters.The reaction readily provides a diverse array of chiral triarylmethanes with high efficiency,enantioselectivity,and excellent functional group compatibility.Moreover,facile follow-up transformations underscore their potential utility in the synthesis of various enantioenriched building blocks.Preliminary mechanistic studies support the plausibility of the remote substitution pathway.

关键词： remote substitution copper catalyst asymmetric catalysis triaryl methanes

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Modifiable risk factors for esophageal cancer in endoscopic screening population:A modeling study

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Chinese Medical Journal 2024年第3期137卷 350-352页

作者： Qian Zhang Fan Wang hao feng Jie Xing Shengtao Zhu hao Zhang Yang Li Wenqiang Wei Shutian Zhang Department of Gastroenterology Beijing Friendship HospitalCapital Medical UniversityNational Clinical Research Center for Digestive DiseaseBeijing Digestive Disease CenterBeijing Key Laboratory for Precancerous Lesion of Digestive DiseaseBeijing 100050China Center for Applied Statistics and School of Statistics Renmin University of ChinaBeijing 100872China Statistical Consulting Center Renmin University of ChinaBeijing 100872China National Cancer Center National Clinical Research Center for CancerCancer InstituteChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Department of Gastroenterology Jizhong Energy Fengfeng Group HospitalHandanHebei 056000China RSS and China-Re Life Joint Lab on Public Health and Risk Management Renmin University of ChinaBeijing 100872China

To the Editor:Esophageal cancer,one of the most common cancer types in China,with an estimated 346,633 new cases and 323,600 deaths in 2022,is becoming an increasingly serious clinical and public health problem.^([1])The successful promotion of the self-management strategy has indicated that lifestyle modifications can be valuable in the primary prevention of cancer development.Adopting a healthy lifestyle has become a novel strategy for primary prevention and risk reduction in high-risk areas.Previous epidemiological studies have identified several lifestyle-related risk factors for esophageal cancer,including smoking and diet.^([2])Each factor can typically explain a modest proportion of cancer risk.However,when combined,these known risk factors may substantially affect the risk of esophageal cancer.Nevertheless,some risk factors for esophageal cancer are non-modifiable,including age,low socioeconomic status,and family history.Whether and how these non-modifiable risk factors affect primary cancer prevention by intervening with modifiable risk factors remain unclear.

关键词： esophageal prevention promotion

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Achieving high-efficient photocatalytic persulfate-activated degradation of tetracycline via carbon dots modified MIL-101(Fe)octahedrons

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Chinese Journal of Chemical Engineering 2024年第2期66卷 298-309页

作者： hao Yuan Xinhai Sun Shuai Zhang Weilong Shi feng Guo School of Material Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China

The synergistic reaction of photocatalysis and advanced oxidation is a valid strategy for the degradation of harmful antibiotic wastewater.Herein,carbon dots(CDs)modified MIL-101(Fe)octahedrons to form CDs/MIL-101(Fe)composite photocatalyst was synthesized for visible light-driven photocatalytic/persulfate(PS)-activated tetracycline(TC)degradation.The electron spin resonance(ESR)spectra,scavenging experiment and electrochemical analysis were carried out to reveal that the high visible light-driven photocatalytic degradation activity of TC over CDs/MIL-101(Fe)photocatalysts is not only ascribed to the production of free active radicals in the CDs/MIL-101(Fe)/PS system(·OH,·SO_(4-),^(1)O_(2),h^(+)and·O_(2)^(-))but also attributed to the consumption of electrons caused by the PS,which can suppress the recombination of photo-generated carriers as well as strong light scattering and electron trapping effects of CDs.Finally,the possible degradation pathways were proposed by analyzing intermediates via liquid chromatography-mass spectrometry technique.This research presents a rational design conception to construct a CDs/PS-based photocatalysis/advanced oxidation technology with high-efficient degradation activity for the remediation of organic antibiotic pollutant wastewater and for the improvement of carrier transport kinetics of photocatalysts.

关键词： Carbon dots MIL-101(Fe) Photocatalytic Persulfate activation Tetracycline degradation

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