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Trial application of the envelope method to the potential ambiguity problem

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Nuclear Science and Techniques 2024年第1期35卷 73-80页

作者： Li-Yuan hu Yu-Shou Song Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin Engineering UniversityHarbin 150001China College of Nuclear Science and Technology Harbin Engineering UniversityHarbin 150001China Key Laboratory of Nuclear Safety and Advanced Nuclear Energy Technology Ministry of Industry and Information TechnologyHarbin 150001China

The optical potential ambiguity is a long-standing problem in the analysis of elastic scattering data.For a specific collid-ing system,ambiguous potential families can lead to different behaviors in the nearside and farside scattering components.By contrast,the envelope method can decompose the experimental data into two components with negative and positive deflection angles,respectively.Hence,a question arises as to whether the comparison between the calculated nearside(or farside)component and the derived positive-deflection-angle(or negative-deflection-angle)component can help analyze the potential ambiguity problem.In this study,we conducted a trial application of the envelope method to the potential ambiguity problem.The envelope method was improved by including uncertainties in the experimental data.The colliding systems of 16O+28Si at 215.2 MeV and 12C+12C at 1016 MeV were considered in the analyses.For each colliding system,the angular distribution experimental data were described nearly equally well by two potential sets,one of which is“surface transpar-ent”and the other is refractive.The calculated angular distributions were decomposed into nearside and farside scattering components.Using the improved envelope method,the experimental data were decomposed into the positive-deflection-angle and negative-deflection-angle components,which were then compared with the calculated nearside and farside components.The capability of the envelope method to analyze the potential ambiguities was also discussed.

关键词： Elastic scattering Optical potential ambiguities Envelope method Nearside/farside decomposition

Exploring the correlation between temperature and crime:A case-crossover study of eight cities in America

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Journal of Safety Science and Resilience 2024年第1期5卷 13-36页

作者： Jinming hu Xiaofeng hu Xin’ge Han Yan Lin huanggang Wu Bing Shen School of Information Technology and Cyber Security People’s Public Security University of ChinaBeijing 100038China Center for Capital Social Safety People’s Public Security University of ChinaBeijing 100038China China Association for Public Safety Beijing 100084China School of Emergency Management and Safety Engineering China University of Mining and TechnologyBeijing 100083China School of International Police Studies People’s Public Security University of ChinaBeijing 100038China

Recent years have seen increasing academic interest in exploring the correlation between temperature and crime.However,it is uncertain whether similar long-term trends or seasonality(rather than causal effect)of temper-ature and crime is the major reason for the observed correlation between them.To explore whether there is still a correlation between temperature and crime when long-term trends and seasonal cycles are filtered out,we use the Kalman filter to decompose the time series of temperature and crimes,and then the fast Fourier transform is used to calculate the exact circle of their seasonality separately.Based on that,the box-plot method and linear regression are used to explore the correlation between temperature residuals and crime residuals.The results show that more than half of the crime types have similar seasonal cycles(approximately 1 year)to that of temperature.Moreover,the daily residual analyses show that temperature residuals have a positive correlation with assault and robbery residuals in all cities,whose average slopes are more than 0.1.The other four types of crimes vary greatly from case to case.The temperature residuals show a weak correlation with the residuals of some crime types.

关键词： Time series decomposition Crime Temperature Kalman filter Fast fourier transform

High-order time-reversal symmetry breaking normal state

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 136-148页

作者： Meng Zeng Lun-hui hu Hong-Ye hu Yi-Zhuang You Congjun Wu Department of Physics University of CaliforniaSan DiegoCalifornia 92093USA Department of Physics Zhejiang UniversityHangzhou 310058China New Cornerstone Science Laboratory Department of PhysicsSchoolof ScienceWestlake UniversityHangzhou 30024China Institute for Theoretical Sciences Westlake UniversityHangzhou 310024China Key Laboratory for Quantum Materials of Zhejiang Province School of ScienceWestlake UniversityHangzhou 310024China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Spontaneous time-reversal symmetry breaking plays an important role in studying strongly correlated unconventional superconductors.When two superconducting gap functions with different symmetries compete,the relative phase channel(θ_(-)≡θ_(1)-θ_(2))exhibits an Ising-type Z_(2) symmetry due to the second order Josephson coupling,where θ_(1,2) are the phases of two gap functions.In contrast,the U(1) symmetry in the channel of θ_(+)≡(θ_(1)+θ_(2))/2 is intact.The phase locking,i.e.,ordering of θ_(-),can take place in the phase fluctuation regime before the onset of superconductivity,i.e.,when θ_(+) is disordered.If θ_(-) is pinned at ±π/2,then timereversal symmetry is broken in the normal state,otherwise,if θ_(-)=0,or,π,rotational symmetry is broken,leading to a nematic normal state.In both cases,the order parameters possess a 4-fermion structure beyond the scope of mean-field theory,which can be viewed as a high order symmetry breaking.We employ an effective two-component XY-model assisted by a renormalization group analysis to address this problem.As a natural by-product,we also find the other interesting intermediate phase corresponds to ordering of θ_+ but with θ_(-)disordered.This is the quartetting,or,charge-4e,superconductivity,which occurs above the low temperature Z_(2)-breaking charge-2e superconducting phase.Our results provide useful guidance for studying novel symmetry breaking phases in strongly correlated superconductors.

关键词： superconductivity strong correlation time-reversal breaking charge-4e

Electricity Theft Detection Method Based on Ensemble Learning and Prototype Learning

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 213-224页

作者： Xinwu Sun Jiaxiang hu Zhenyuan Zhang Di Cao Qi huang Zhe Chen Weihao hu the School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengduChina Southwest University of Science and TechnologyChengduChina

With the development of advanced metering infrastructure(AMI),large amounts of electricity consumption data can be collected for electricity theft detection.However,the imbalance of electricity consumption data is violent,which makes the training of detection model challenging.In this case,this paper proposes an electricity theft detection method based on ensemble learning and prototype learning,which has great performance on imbalanced dataset and abnormal data with different abnormal level.In this paper,convolutional neural network(CNN)and long short-term memory(LSTM)are employed to obtain abstract feature from electricity consumption data.After calculating the means of the abstract feature,the prototype per class is obtained,which is used to predict the labels of unknown samples.In the meanwhile,through training the network by different balanced subsets of training set,the prototype is representative.Compared with some mainstream methods including CNN,random forest(RF)and so on,the proposed method has been proved to effectively deal with the electricity theft detection when abnormal data only account for 2.5%and 1.25%of normal data.The results show that the proposed method outperforms other state-of-the-art methods.

关键词： Electricity theft detection ensemble learning prototype learning imbalanced dataset deep learning abnormal level

Total synthesis of a putative yuzurimine-type Daphniphyllum alkaloid C_(14)–epi-deoxycalyciphylline H

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Chinese Chemical Letters 2024年第4期35卷 336-339页

作者： Jingping hu Jing Xu Shenzhen Grubbs Institute and Department of Chemistry and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis Southern University of Science and TechnologyShenzhen 518055China

One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contiguous stereogenic centers, and vicinal all-carbon quaternary centers make these alkaloids formidable challenge for synthetic chemists. Recently, synthesis of these alkaloids has received extensive attention from our community. Herein, we wish to report the total synthesis of C_(14)–epideoxycalyciphylline H, a putative member of yuzurimine-type alkaloid subfamily. Key transformations employed in our approach include an intramolecular Prins reaction and a Pd-catalyzed enyne cycloisomerization. In addition, synthesis of a daphnezomine L-type alkaloid, paxdaphnidine A, was also studied.

关键词： Total synthesis Daphniphyllum alkaloids Yuzurimine-type alkaloids Prins reaction Enyne cycloisomerization

Dynamic Response of Foundations during Startup of High-Frequency Tunnel Equipment

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 821-844页

作者： Dawei Ruan Mingwei hu College of Civil and Transportation Engineering Shenzhen UniversityShenzhen518060China State Key Laboratory of Intelligent Geotechnics and Tunnelling Shenzhen UniversityShenzhen518060China Key Laboratory of Coastal Urban Resilient Infrastructures of Ministry of Education Shenzhen UniversityShenzhen518060China Underground Polis Academy Shenzhen UniversityShenzhen518060China Shenzhen Key Laboratory of Green Efficient and Intelligent Construction of Underground Metro StationShenzhen UniversityShenzhen518060China

The specialized equipment utilized in long-line tunnel engineering is evolving towards large-scale,multifunctional,and complex orientations.The vibration caused by the high-frequency units during regular operation is supported by the foundation of the units,and the magnitude of vibration and the operating frequency fluctuate in different engineering contexts,leading to variations in the dynamic response of the foundation.The high-frequency units yield significantly diverse outcomes under different startup conditions and times,resulting in failure to meet operational requirements,influencing the normal function of the tunnel,and causing harm to the foundation structure,personnel,and property in severe cases.This article formulates a finite element numerical computation model for solid elements using three-dimensional elastic body theory and integrates field measurements to substantiate and ascertain the crucial parameter configurations of the finite element model.By proposing a comprehensive startup timing function for high-frequency dynamic machines under different startup conditions,simulating the frequency andmagnitude variations during the startup process,and suggesting functions for changes in frequency and magnitude,a simulated startup schedule function for high-frequency machines is created through coupling.Taking into account the selection of the transient dynamic analysis step length,the dynamic response results for the lower dynamic foundation during its fundamental frequency crossing process are obtained.The validation checks if the structural magnitude surpasses the safety threshold during the critical phase of unit startup traversing the structural resonance region.The design recommendations for high-frequency units’dynamic foundations are provided,taking into account the startup process of the machine and ensuring the safe operation of the tunnel.

关键词： Tunnel equipment high-frequency units startup conditions transient dynamics dynamic response foundation design

Epidemiological features of seasonal influenza transmission among 11 climate zones in Chinese mainland

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Infectious Diseases of Poverty 2024年第1期13卷 27-41页

作者： Xiaohan Si Liping Wang Kerrie Mengersen Wenbiao hu Ecosystem Change and Population Health Research Group School of Public Health and Social WorkQueensland University of TechnologyBrisbaneQLD 4059Australia Information Center Chinese Center for Disease Control and PreventionBeijing 102206China School of Mathematical Sciences Queensland University of TechnologyBrisbaneQLD 4000Australia

Background Previous studies provided some evidence of meteorological factors influence seasonal influenza transmission patterns varying across regions and latitudes.However,research on seasonal influenza activities based on climate zones are still in lack.This study aims to utilize the ecological-based Koppen Geiger climate zones classif-cation system to compare the spatial and temporal epidemiological characteristics of seasonal influenza in Chinese mainland and assess the feasibility of developing an early warning system.Methods Weekly influenza cases number from 2014 to 2019 at the county and city level were sourced from China National Notifiable Infectious Disease Report Information System.Epidemic temporal indices,time series seasonality decomposition,spatial modelling theories including Moran's/and local indicators of spatial association were applied to identify the spatial and temporal patterns of influenza transmission.Results All climate zones had peaks in Winter-Spring season.Arid,desert,cold(BWk)showed up the first peak.Only Tropical,savannah(Aw)and Temperate,dry winter with hot summer(Cwa)zones had unique summer peak.Temper-ate,no dry season and hot summer(Cfa)zone had highest average incidence rate(IR)at 1.047/100,000.The Global Moran's/showed that average IR had significant clustered trend(z=53.69,P<0.001),with local Moran's/identi-fied high-high cluster in Cfa and Cwa.IR differed among three age groups between climate zones(O-14 years old:F=26.80,P<0.001;15-64 years old:F=25.04,P<0.001;Above 65 years old:F=5.27,P<0.001).Age group 0-14 years had highest average IR in Cwa and Cfa(IR=6.23 and 6.21)with unique dual peaks in winter and spring season showed by seasonality decomposition.Conclusions Seasonal influenza exhibited distinct spatial and temporal patterns in different climate zones.Seasonal influenza primarily emerged in BWk,subsequently in Cfa and Cwa.Cfa,Cwa and BSk pose high risk for seasonal influ-enza epidemics.The research finds will provide scientific evidence for developing seasonal infl

关键词： Seasonal influenza Koppen Geiger climate zones classification system Chinese mainland Seasonality decomposition Local indicators of spatial association

Phosphorylation of PB2 at serine 181 restricts viral replication and virulence of the highly pathogenic H5N1 avian influenza virus in mice

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Virologica Sinica 2024年第1期39卷 97-112页

作者： Jiao hu Zixiong Zeng Xia Chen Manyu Zhang Zenglei hu Min Gu Xiaoquan Wang Ruyi Gao Shunlin hu Yu Chen Xiaowen Liu Daxin Peng Xiufan Liu Animal Infectious Disease Laboratory School of Veterinary MedicineYangzhou UniversityYangzhou225009China Joint International Research Laboratory of Agriculture and Agri-Product Safety The Ministry of Education of ChinaYangzhou University225009China Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonosis Yangzhou UniversityYangzhou225009China Key Laboratory of Prevention and Control of Biological Hazard Factors(Animal Origin)for Agri-food Safety and Quality Ministry of Agriculture of China(26116120)Yangzhou UniversityYangzhou225009China

Influenza A virus(IAV)continues to pose a pandemic threat to public health,resulting a high mortality rate annually and during pandemic years.Posttranslational modification of viral protein plays a substantial role in regulating IAV infection.Here,based on immunoprecipitation(IP)-based mass spectrometry(MS)and purified virus-coupled MS,a total of 89 phosphorylation sites distributed among 10 encoded viral proteins of IAV were identified,including 60 novel phosphorylation sites.Additionally,for the first time,we provide evidence that PB2 can also be acetylated at site K187.Notably,the PB2 S181 phosphorylation site was consistently identified in both IP-based MS and purified virus-based MS.Both S181 and K187 are exposed on the surface of the PB2 protein and are highly conserved in various IAV strains,suggesting their fundamental importance in the IAV life cycle.Bioinformatic analysis results demonstrated that S181E/A and K187Q/R mimic mutations do not significantly alter the PB2 protein structure.While continuous phosphorylation mimicked by the PB2 S181E mutation substantially decreases viral fitness in mice,PB2 K187Q mimetic acetylation slightly enhances viral virulence in mice.Mechanistically,PB2 S181E substantially impairs viral polymerase activity and viral replication,remarkably dampens protein stability and nuclear accumulation of PB2,and significantly weakens IAV-induced inflammatory responses.Therefore,our study further enriches the database of phosphorylation and acetylation sites of influenza viral proteins,laying a foundation for subsequent mechanistic studies.Meanwhile,the unraveled antiviral effect of PB2 S181E mimetic phosphorylation may provide a new target for the subsequent study of antiviral drugs.

关键词： H5N1 influenza virus PB2 Phosphorylation Acetylation Viral fitness Mice

On n-universal quadratic forms over dyadic local fields

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Science China Mathematics 2024年第7期67卷 1481-1506页

作者： Zilong He Yong hu School of Computer Science and Technology Dongguan University of TechnologyDongguan523808China Department of Mathematics Southern University of Science and TechnologyShenzhen518055China

Let n≥2 be an integer. We give necessary and sufficient conditions for an integral quadratic form over dyadic local fields to be n-universal by using invariants from Beli's theory of bases of norm generators.Also, we provide a minimal set for testing n-universal quadratic forms over dyadic local fields, as an analogue of Bhargava and Hanke's 290-theorem(or Conway and Schneeberger's 15-theorem) on universal quadratic forms with integer coefficients.

关键词： integral quadratic forms n-universal quadratic forms dyadic fields 290-theorem