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Numerical investigation on free air blast loads generated from center-initiated cylindrical charges with varied aspect ratio in arbitrary orientation

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Defence Technology（防务技术） 2022年第9期18卷 1662-1678页

作者： Chu Gao xiang-zhen kong Qin Fang Jian Hong Yin Wang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLAJiangsuNanjing210007China Inner Mongolia University of Finance and Economics Inner MongoliaHohhot010070China Engineering Research Center for Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityJiangsuNanjing211189China

In current guidelines, the free air blast loads(overpressure and impulse) are determined by spherical charges, although most of ordnance devices are more nearly cylindrical than spherical in geometry. This may result in a great underestimation of blast loads in the near field and lead to an unsafe ***, there is still a lack of systematic quantitative analysis of the blast loads generated from cylindrical charges. In this study, a numerical model is developed by using the hydrocode AUTODYN to investigate the influences of aspect ratio and orientation on the free air blast loads generated from center-initiated cylindrical charges. This is done by examining the pressure contours, the peak overpressures and impulses for various aspect ratios ranged from 1 to 8 and arbitrary orientation monitored along every azimuth angle with an interval of 5°. To characterize the distribution patterns of blast loads,three regions, i.e., the axial region, the vertex region and the radial region are identified, and the propagation of blast waves in each region is analyzed in detail. The complexity of blast loads of cylindrical charges is found to result from the bridge wave and its interaction with primary waves. Several empirical formulas are presented based on curve-fitting the numerical data, including the orientation where the maximum peak overpressure emerges, the critical scaled distance beyond which the charge shape effect could be neglected and blast loads with varied aspect ratio in arbitrary orientation, all of which are useful for blast-resistant design.

关键词： Cylindrical charge Blast loads Aspect ratio Azimuth angle Bridge wave

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Mesoscopic modelling of UHPCC material under dynamic tensile loadings

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Defence Technology（防务技术） 2023年第5期23卷 75-91页

作者： xiang-zhen kong Shang-bin Yang Tao Zhang Qin Fang Heng-bo xiang Rui-wen Li Engineering Research Centre for Safety and Protection of Explosion&Impact of Ministry of Education Southeast UniversityJiangsu Nanjing211189China State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLAJiangsu Nanjing210007China Research Institute for National Defense Engineering of Academy of Military Science PLALuoyang471023China School of Civil Engineering and Architecture Xi'an University of TechnologyXi'an710048China

This paper presents a new 3D mesoscopic model of ultra-high performance cement-based composite(UHPCC)to investigate its dynamic tensile *** this model,the UHPCC is regarded as a two-phase material composed of cementitious matrix and randomly distributed *** model is established using the commercial software LS-DYNA and involves generating the randomly distributed fiber elements with considerations of diameter,length,orientation and volume fraction,and then fully constraining them with the *** particular,to capture the slipping effect between fibers and matrix that has a strong influence on the dynamic tensile behavior,the fibers are modelled by a fictitious material represented by the load-slip *** strain-rate effect of slipping force neglected in most of previous studies is considered by calibrating constitutive parameters of the fictitious material under different strain-rates based on the single fiber pullout ***,the 3D mesoscopic model is validated against three sets of tension-dominated experiments covered a wide range of loading *** predictions demonstrate that strain-rate effect of slipping force must be considered,and the neglect of it may lead to a great underestimation of the dynamic tensile strength of UHPCC material and would unavoidably underestimate the blast resistance of UHPCC components.

关键词： UHPCC Dynamic tensile behavior Mesoscopic model Strain-rate effect Impact and blast loadings

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Gene Expression Data Classification Using Consensus Independent Component Analysis

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Genomics, Proteomics & Bioinformatics 2008年第2期6卷 74-82页

作者： Chun-Hou zheng De-Shuang Huang xiang-zhen kong Xing-Ming Zhao College of Information and Communication Technology Qufu Normal University Rizhao 276826 China Intelligent Computing Lab Institute of Intelligent Machines Chinese Academy of Sciences Hefei 230031China

We propose a new method for tumor classification from gene expression data, which mainly contains three steps. Firstly, the original DNA microarray gene expression data are modeled by independent component analysis （ICA）. Secondly, the most discriminant eigenassays extracted by ICA are selected by the sequential floating forward selection technique. Finally, support vector machine is used to classify the modeling data. To show the validity of the proposed method, we applied it to classify three DNA microarray datasets involving various human normal and tumor tissue samples. The experimental results show that the method is efficient and feasible.

关键词： independent component analysis feature selection support vector machine gene expression data

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Scanning reproducible brain-wide associations:sample size is all you need?

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Psychoradiology 2022年第3期2卷 67-68页

作者： xiang-zhen kong Chenghui Zhang Yinuo Liu Yi Pu Department of Psychology and Behavioral Sciences Zhejiang UniversityHangzhou 310028China Department of Psychiatry of Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou 310016China Department of Neuroscience Max Planck Institute for Empirical AestheticsFrankfurt am Main 60322Germany

Back to 1874,John Hughlings Jackson,a pioneer in neurology who had profound knowledge about the structure of the brain,posited that“difference of[brain]structure of necessity implies difference in function”.Since then,understanding the relationship between the brain structure and function in humans has become an important endeavor in neuroscience research.

关键词： size function implies

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Adaptive total variation constraint hypergraph regularized NMF for single-cell RNA-seq data analysis

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Quantitative Biology 2021年第4期9卷 451-462页

作者： Ya-Li Zhu Xiao-Ning Zhang Chuan-Yuan Wang Jin-Xing Liu xiang-zhen kong School of Computer Science Qufu Normal UniversityRizhao 276826China

Background:Single-cell RNA sequencing(scRNA-seq)data provides a whole new view to study disease and cell differentiation *** the explosive increment of scRNA-seq data,effective models are demanded for mining the intrinsic biological ***:This paper proposes a novel non-negative matrix factorization(NMF)method for clustering and gene coexpression network analysis,termed Adaptive Total Variation Constraint Hypergraph Regularized NMF(ATV-HNMF).ATV-HNMF can adaptively select the different schemes to denoise the cluster or preserve the cluster boundary information between clusters based on the gradient ***,ATV-HNMF incorporates hypergraph regularization,which can consider high-order relationships between cells to reserve the intrinsic structure of the ***:Experiments show that the performances on clustering outperform other compared methods,and the network construction results are consistent with previous studies,which illustrate that our model is effective and ***:From the clustering results,we can see that ATV-HNMF outperforms other methods,which can help us to understand the *** can discover many disease-related genes from the constructed network,and some are worthy of further clinical exploration.

关键词： adaptive total variation single-cell RNA sequencing network analysis nonnegative matrix factorization hypergraph

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Bending failure of a concrete gravity dam subjected to underwater explosion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第12期21卷 976-991页

作者： Xie-ping HUANG Jing HU Xue-dong ZHANG Zi-tao ZHANG xiang-zhen kong Institute of Geotechnical Engineering Zhejiang UniversityHangzhou 310058China China Institute of Water Resources and Hydropower Research Beijing 100048China Army Engineering University of PLA Nanjing 210007China

Dam structures are prime targets during wars,and a tragedy is likely to happen in a populated area downstream of a dam exposed to ***,experimental investigations of the failure of a concrete gravity dam subjected to underwater explosion(UNDEX)are extremely *** this study,centrifuge tests and numerical simulations were performed to investigate the failure of a concrete gravity dam subjected to a near-field *** results revealed the existence of two tensile fractures inside the dam,one in the upper part and the other in the lower *** to the narrowness of the upper part,there were coupled effects of bending tensile loads in the upstream face and a reflected tensile stress wave in the downstream face,resulting in severe tensile damage to the upper part in both the upstream and downstream *** fracture in the lower part was measured at around one third of the height of the *** fracture was produced mainly by the bending tensile loads in the upstream *** by those loads,this fracture started from the upstream face and developed towards the downstream face,with a horizontal angle of about 15?.The underlying mechanisms behind the two tensile fractures were confirmed by recorded strain *** dam failures presented in this study are similar to those produced in historical wars,in which dams were under similar attack scenarios.

关键词： Centrifuge test Numerical simulation Concrete gravity dam Underwater explosion(UNDEX) Bending failure

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贝叶斯因子及其在JASP中的实现

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心理科学进展 2018年第6期26卷 951-965页

作者：胡传鹏孔祥祯 Eric-Jan Wagenmakers Alexander Ly 彭凯平清华大学心理学系北京100084 Neuroimaging Center Johannes Gutenberg University Medical Center55131 MainzGermany Language and Genetics Department Max Planck Institute for Psycholinguistics6500 AH NijmegenThe Netherlands Department of Psychological Methods University of Amsterdam1018 VZ AmsterdamThe Netherlands Centrum Wiskunde&Informatica 1090 GB AmsterdamThe Netherlands

统计推断在科学研究中起到关键作用,然而当前科研中最常用的经典统计方法——零假设检验(Null hypothesis significance test,NHST)却因难以理解而被部分研究者误用或滥用。有研究者提出使用贝叶斯因子(Bayes factor)作为一种替代和(或... 详细信息

统计推断在科学研究中起到关键作用,然而当前科研中最常用的经典统计方法——零假设检验(Null hypothesis significance test,NHST)却因难以理解而被部分研究者误用或滥用。有研究者提出使用贝叶斯因子(Bayes factor)作为一种替代和(或)补充的统计方法。贝叶斯因子是贝叶斯统计中用来进行模型比较和假设检验的重要方法,其可以解读为对零假设H_0或者备择假设H_1的支持程度。其与NHST相比有如下优势:同时考虑H_0和H_1并可以用来支持H_0、不"严重"地倾向于反对H_0、可以监控证据强度的变化以及不受抽样计划的影响。目前,贝叶斯因子能够很便捷地通过开放的统计软件JASP实现,本文以贝叶斯t检验进行示范。贝叶斯因子的使用对心理学研究者来说具有重要的意义,但使用时需要注意先验分布选择的合理性以及保持数据分析过程的透明与公开。

关键词：贝叶斯因子贝叶斯学派频率学派假设检验 JASP

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Critical Behaviour of the Gaussian Model on Sierpinski Carpets

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Chinese Physics Letters 2001年第7期18卷 882-884页

作者： LIN zhen-Quan kong xiang-Mu Department of Physics Wenzhou Normal CollegeWenzhou 325027 Department of Physics Qufu Normal UniversityQufu 273165

The Gaussian model on Sierpinski carpets with two types of nearest neighbour interactions K and Kw and two corresponding types of the *** constants b and bw is constructed by generalizing that on translationally invariant square *** critical behaviours are studied by the renormalization-group approach and spin rescaling *** are found to be quite different from that on translationally invariant square *** are two critical points at(K^(*)=b,K^(*)_(w)=0)and(K^(*)=0,K^(*)_(w)=bw),and the correlation length critical exponents are calculated.

关键词： method critical invariant

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Kinetic Behavior of Exchange-Driven Growth with Catalyzed-Birth Processes

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Communications in Theoretical Physics 2006年第6X期46卷 1113-1120页

作者： WANG Hai-Feng LIN zhen-Quan kong xiang-Mu Department of Physics Wenzhou University Wenzhou 325027 China Department of Physics Qufu Normal University Qufu 273165 China

Two catalyzed-birth models of n-species （n ≥ 2） aggregates with exchange-driven growth processes are proposed and compared. In the first one, the exchange reaction occurs between any two aggregates Ak^m and Af^m of the same species with the rate kernels Km（k,j）= Kmkj （m = 1, 2,... ,n, n ≥ 2）, and aggregates of A^n species catalyze a monomer-birth of A^l species （l = 1, 2 , n - 1） with the catalysis rate kernel Jl（k,j） -Jlkj^v. The kinetic behaviors are investigated by means of the mean-field theory. We find that the evolution behavior of aggregate-size distribution ak^l（t） of A^l species depends crucially on the value of the catalysis rate parameter v：（i） ak^l（t） obeys the conventional scaling law in the case of v ≤ 0, （ii） ak^l（t） satisfies a modified scaling form in the case of v 〉 0. In the second model, the mechanism of monomer-birth of An-species catalyzed by A^l species is added on the basis of the first model, that is, the aggregates of A^l and A^n species catalyze each other to cause monomer-birth. The kinetic behaviors of A^l and A^n species are found to fall into two categories for the different v：（i） growth obeying conventional scaling form with v ≤ 0, （ii） gelling at finite time with v 〉 0.

关键词： behavior exchange-driven growth catalyzed-birth scaling law rate equations

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Molecular characterization and phylogenetic analysis of three odorant binding protein gene transcripts in Dendrolimus species （Lepidoptera： Lasiocampidae）

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Insect Science 2014年第5期21卷 597-608页

作者： Su-Fang Zhang zhen Zhang xiang-Bo kong Hong-Bin Wang Key Laboratory of Forest Protection Research Institute of Forest Ecology Environment and Protection Chinese Academy of ForestryState Forestry Administration Beijing China

Pine caterpillar moths, Dendrolimus spp. （Lepidoptera： Lasiocampidae）, are serious economic pest of pines. Previously, phylogenetic analyses of Dendrolimus using different methods yielded inconsistent results. The chemosensory systems of insects may play fundamental roles in promoting speciation. Odorant-binding proteins （OBPs） participate in the first step of odor detection. Studying the evolution of OBPs in closely related species may help us to identify their role in speciation. We identified three OBPs - one pheromone-binding protein and two general odorant-binding proteins - from male antennae of four Dendrolimus species, D. superans （Butler）, D. punctatus （Walker）, D. kikuchii Matsumura, and D. houi Lajonquiere, the olfactory recognition systems of which had not been previously investigated. We analyzed their molecular characteristics and compared their sequences to those of OBPs in D. tabulaeformis Tsai et Liu. Ka/Ks ratio analyses among the five Dendrolimus species indicate that PBP1 genes experienced more evolutionary pressure than the GOBPs. Phylogenetic relationships of PBP1 and GOBP1 both indicated that D. houi was the basal species, then branched D. kikuchii, while D. tabulaeformis, D. punctatus, and D. superans evolved more recently. These relationships are consistent with the changes in sex pheromone components of these five species. Dendrolimus tabulaeformis and D. punctatus are closely related sister species. However, the distances among GOBP2 sequences in the five Dendrolimus were very short, and the relationships of D. houi and D. la＇kuchii could not be resolved. Integrating our results with those of previous studies, we hypothesized that D. kikuchii, D. punctatus and D. superans evolved from the basal ancestor because of sex pheromone mutations and environmental pressure.

关键词： Dendrolimus general odorant-binding protein Ka/Ks pheromone-binding proteins phylogenetic sex pheromone

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