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Evaluation of the treatment effect of rear slope cutting on hydrodynamic pressure landslides:A case study

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Journal of Mountain Science 2023年第7期20卷 1968-1983页

作者： WANG Li HUANG Jun-jie CHEN Yong WANG Shi-mei FAN Zhi-hong GUO fei LI xiao-wei Key Laboratory of Geological Hazards on Three Gorges Reservoir Area(China Three Gorges University) Ministry of EducationYichang 443002China College of Civil Engineering&Architecture China Three Gorges UniversityYichang 443002China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China Central-South Institute of Metallurgical Geology Yichang 443002China

After the impoundment of the Three Gorges Reservoir,some huge ancient landslides were reactivated and deformed,showing typical hydrodynamic pressure landslide *** Baishuihe landslide was a typical hydrodynamic pressure *** management department conducted slope cutting treatments from 2018 to *** evaluate the treatment effect of rear slope cutting,this study analyzed the data of the surface deformation survey and field monitoring over the past 20 years and the characteristics of the reservoir water-triggered Baishuihe landslide deformation,and calculated the seepage field,displacement field,and stability coefficient before and after landslide *** results showed that the deformation of the Baishuihe landslide was primarily related to a decrease in the reservoir water *** to the poor permeability of the landslide soil,the decrease in the reservoir water level produced a seepage force pointing to the outside of the landslide body,leading to the step deformation of the landslide *** landslide was treated by rear slope cutting,and the“step”deformation of the landslide disappeared after *** hydrodynamic pressure caused by the change in reservoir water after cutting the slope did not ***,as the slope cutting greatly reduced the overall sliding force of the landslide,its stability was greatly ***,high stability can still be ensured under extreme rainfall after *** cutting is effective for treating hydrodynamic pressure *** study can provide effective technical support for the treatment of reservoir landslides.

关键词： Hydrodynamic pressure landslide Three Gorges Reservoir Slope cutting Load reduction Landslide monitoring Ancient landslides Reservoir water level fluctuation

Brake Orbits of First Order Convex Hamiltonian Systems with Particular Anisotropic Growth

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Acta Mathematica Sinica,English Series 2020年第2期36卷 171-178页

作者： xiao fei ZHANG Chun Gen LIU School of Mathematics and Statistics Shanxi Datong UniversityDatong 037009P.R.China School of Mathematics and Information Science Guangzhou UniversityGuangzhou 510006P.R.China

Combining the dual least action principle with Mountain-pass lemma,we obtain the existence of brake orbits for first-order convex Hamiltonian systems with particular anisotropic growth.

关键词： Hamiltonian system brake orbit anisotropic grow th Mountain-pass lemma

Ince-Strutt Stability Charts for Ship Parametric Roll Resonance in Irregular Waves

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China Ocean Engineering 2017年第4期31卷 447-457页

作者： ZHANG xiao YANG He-zhen xiao fei XU Pei-ji National Key Laboratory on Ship Vibration &Noise China Ship Development and Design Center State Key Laboratory of Ocean Engineering School of Naval Architecture.Ocean and Civil EngineeringShanghai Jiao Tong University School of Civil and Environmental Engineering Nanyang Technological University

Ince-Strutt stability chart of ship parametric roll resonance in irregular waves is conducted and utilized for the exploration of the parametric roll resonance in irregular waves. Ship parametric roll resonance will lead to large amplitude roll motion and even wreck. Firstly, the equation describing the parametric roll resonance in irregular waves is derived according to Grim’s effective theory and the corresponding Ince-Strutt stability charts are obtained. Secondly, the differences of stability charts for the parametric roll resonance in irregular and regular waves are compared. Thirdly, wave phases and peak periods are taken into consideration to obtain a more realistic sea condition. The influence of random wave phases should be taken into consideration when the analyzed points are located near the instability boundary. Stability charts for different wave peak periods are various. Stability charts are helpful for the parameter determination in design stage to better adapt to sailing condition. Last, ship variables are analyzed according to stability charts by a statistical approach. The increase of the metacentric height will help improve ship stability.

关键词： parametric instability parametric rolling multi-frequency irregular waves Ince-Strutt stability chart

Asymptotic inference for AR(1) panel data

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Applied Mathematics(A Journal of Chinese Universities) 2020年第3期35卷 265-280页

作者： SHEN Jian-fei PANG Tian-xiao School of Mathematical Sciences Zhejiang UniversityHangzhou 310027China

A general asymptotic theory is given for the panel data AR(1) model with time series independent in different cross sections. The theory covers the cases of stationary process, local to unity process, unit root process, mildly integrated, mildly explosive and explosive processes. It is assumed that the cross-sectional dimension and time-series dimension are respectively N and T. The results in this paper illustrate that whichever the process is, with an appropriate regularization, the least squares estimator of the autoregressive coefficient converges in distribution to a normal distribution with rate at least O(N-1/3). Since the variance is the key to characterize the normal distribution, it is important to discuss the variance of the least squares estimator. We will show that when the autoregressive coefficient ρ satisfies |ρ| 1. ρ = 1 is the critical point where the convergence rate changes radically. The transition process is studied by assuming ρ depending on T and going to 1. An interesting phenomenon discovered in this paper is that, in the explosive case, the least squares estimator of the autoregressive coefficient has a standard normal limiting distribution in the panel data case while it may not has a limiting distribution in the univariate time series case.

关键词： AR(1)model Least squares estimator Limiting distribution Non-stationray Panel data

Information and knowledge behind data from underground rock grouting

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第6期13卷 1326-1339页

作者： fei xiao Qian Liu Zhiye Zhao Department of Civil Engineering Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Civil and Environmental Engineering Nanyang Technological University50 Nanyang Avenue639798Singapore

Data related to the pre-grouting work of a large underground project are systematically analyzed to reveal the mechanism behind,to shed some light on the execution of practical grouting,and to enrich the theory of engineering *** is generally taken as an effective way for controlling nonignorable water seepage during underground rock *** various models have been developed to guide grouting design or to specify criteria for grouting stop,it does not change the fact that grouting is still highly ***,explanation of the current situation due to grouting complexity is given through step-by-step data analysis,where the impact on grouting parameters from the geological and hydrogeological conditions is investigated,and the grouting features of two tunnels located at the same depth below the sea surface are compared and ***,the data from individual grout hole are used to construct the regional geological conditions via inverse *** is found that grouting of fractured rock masses is accompanied with great uncertainty,and field grouting data can contribute significantly to a better understanding of the regional geological conditions around an underground tunnel or rock cavern.

关键词： Field grouting data Water seepage Rock grouting Inverse modelling Data analytics Geological conditions

A New High-throughput Real-time PCR Assay for the Screening of Multiple Antimicrobial Resistance Genes in Broiler Fecal Samples from China

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Biomedical and Environmental Sciences 2019年第12期32卷 881-892页

作者： CHE Jie LU Jin Xing LI Wen Ge ZHANG Yun fei ZHAO xiao fei YUAN Min BAI Xue mei CHEN Xia LI Juan State Key Laboratory of Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious Disease National Institute for Communicable Disease Control and Prevention Chinese Center for Disease Control and Prevention

Objective Antimicrobial resistance(AMR)has become a global concern and is especially severe in *** effectively and reliably provide AMR data,we developed a new high-throughput real-time PCR assay based on microfluidic dynamic technology,and screened multiple AMR genes in broiler fecal *** A high-throughput real-time PCR system with an new designed integrated fluidic circuit assay were performed AMR gene detection.A total of 273 broiler fecal samples collected from two geographically separated farms were screened AMR *** The new assay with limits of detection ranging from 40.9 to 8,000 copies/*** sensitivity rate,specificity rate,positive predictive value,negative predictive value and correct indices were 99.30%,98.08%,95.31%,99.79%,and 0.9755,*** this assay,we demonstrate that AMR genes are widely spread,with positive detection rates ranging from 0 to 97.07%in 273 broiler fecal *** CTX-M,bla TEM,mcr-1,fex A,cfr,optr A,and int I1 showed over 80%*** dissemination of AMR genes was distinct between the two *** We successfully established a new high-throughput real-time PCR assay applicable to AMR gene surveillance from fecal *** widespread existence of AMR genes detected in broiler farms highlights the current and severe problem of AMR.

关键词： Antimicrobial resistance Antimicrobial resistance gene High-throughput real-time PCR array Broiler fecal sample

Growth traits and nitrogen assimilation-associated physiological parameters of wheat(Triticum aestivum L.) under low and high N conditions

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Journal of Integrative Agriculture 2015年第7期14卷 1295-1308页

作者： ZHANG fei-fei GAO Si ZHAO Yuan-yuan ZHAO xiao-lei LIU xiao-man xiao Kai College of Agronomy Agricultural University of Hebei

In this study, 14 wheat cultivars with contrasting yield and N use efficiency （NUE） were used to investigate the agronomic and NUE-related traits, and the N assimilation-associated enzyme activities under low and high N conditions. Under deficient-N, the cultivars with high N uptake efficiency （UpE） and high N utilization efficiency （UtE） exhibited higher plant biomass, yields, and N contents than those with medium and low NUEs. The high UpE cultivars accumulated more N than other NUE type cultivars. Under sufficient-N, the tested cultivars showed similar patterns in biomass, yield, and N content to those under deficient-N, but the varietal variations in above traits were smaller. In addition, the high UpE cultivars displayed much more of root biomass and larger of root length, surface area, and volume than other NUE type cultivars, indicating that the root morphological traits under N deprivation are closely associated with the plant biomass through its improvement of the N acquisition. The high UtE cultivars showed higher activities of nitrate reductase （NR）, nitrite reductase （NIR）, and gluta- mine synthetase （GS） at stages of seediling, heading and filling than other NUE type cultivars under both low and high N conditions. Moreover, the high UpE and UtE cultivars also displayed higher photosynthetic rate under deficient-N than the medium and low NUE cultivars. Together, our results indicated that the tested wheat cultivars possess dramatically genetic variations in biomass, yield, and NUE. The root morphological traits and the N assimilation enzymatic acitivities play critical roles in regulating N accumulation and internal N translocation under the N-starvation stress, respectively. They can be used as morphological and biochemical references for evaluation of UpE and UtE in wheat.

关键词： wheat (Triticum aestivum L.) low and high N biomass yield nitrogen use efficiency root morphological traits,N assimilzation-associated enzyme photosynthetic rate

Regulation of influenza virus infection by microRNAs

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Journal of Integrative Agriculture 2019年第7期18卷 1421-1427页

作者： ZOU Zhong GONG Wen-xiao HUANG Kun SUN xiao-mei JIN mei-lin State Key Laboratory of Agricultural Microbiology Huazhong Agricultural UniversityWuhan 430070P R.China College of Veterinary Medicine Huazhong Agricultural UniversityWuhan 430070P.R. China Key Laboratory of Development of Veterinary Diagnostic Products Ministry of Agriculture and Rural AffairsWuhan 430070P.R. China

MicroRNAs(miRNAs) are small noncoding RNAs of 18–25 nucleotides(nt) in length that represent key regulators of many normal cellular functions through the inhibition of mRNA translation and mRNA *** date,over 2 500 mature miRNAs have been identified in plants,animals and several types of *** A virus(IAV),which is a negativesense,single-stranded RNA virus,does not encode viral ***,IAV infection can alter the expression of host miRNAs,either in cell culture or in *** turn,host miRNAs regulate IAV life cycle through directly binding to IAV genome or indirectly targeting host factors associated with viral *** this review,we briefly summarized the role and significance of miRNA in relation to IAV *** the role of cellular miRNAs during viral infection may be beneficial to the identification of novel therapeutic strategies to block IAV replication.

关键词： microRNAs influenza A virus pathogenesis therapeutic strategies

An efficient parallel algorithm of variational nodal method for heterogeneous neutron transport problems

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Nuclear Science and Techniques 2024年第4期35卷 29-45页

作者： Han Yin xiao-Jing Liu Teng-fei Zhang School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 2002040China

The heterogeneous variational nodal method(HVNM)has emerged as a potential approach for solving high-fidelity neutron transport ***,achieving accurate results with HVNM in large-scale problems using high-fidelity models has been challenging due to the prohibitive computational *** paper presents an efficient parallel algorithm tailored for HVNM based on the Message Passing Interface *** algorithm evenly distributes the response matrix sets among processors during the matrix formation process,thus enabling independent construction without *** the formation tasks are completed,a collective operation merges and shares the matrix sets among the *** the solution process,the problem domain is decomposed into subdomains assigned to specific processors,and the red-black Gauss-Seidel iteration is employed within each subdomain to solve the response matrix ***-to-point communication is conducted between adjacent subdomains to exchange data along the *** accuracy and efficiency of the parallel algorithm are verified using the KAIST and JRR-3 test *** results obtained with multiple processors agree well with those obtained from Monte Carlo *** parallelization of HVNM results in eigenvalue errors of 31 pcm/-90 pcm and fission rate RMS errors of 1.22%/0.66%,respectively,for the 3D KAIST problem and the 3D JRR-3 *** addition,the parallel algorithm significantly reduces computation time,with an efficiency of 68.51% using 36 processors in the KAIST problem and 77.14% using 144 processors in the JRR-3 problem.

关键词： Neutron transport Variational nodal method Parallelization KAIST JRR-3