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An Upper Bound for the Adjacent Vertex Distinguishing Acyclic Edge Chromatic Number of a Graph

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 137-140页

作者： Xin-sheng Liu Ming-qiang An Yang gao College of Mathematics and Information Science Northwest Normal University Lanzhou 730070 China Tianjin University of Science and Technology Tianjin 300222 China

A proper k-edge coloring of a graph G is called adjacent vertex distinguishing acyclic edge coloring if there is no 2-colored cycle in G and the color set of edges incident to u is not equal to the color set of edges incident to v, where uv ∈E（G）. The adjacent vertex distinguishing acyclic edge chromatic number of G, denoted by χ＇αα（G）, is the minimal number of colors in an adjacent vertex distinguishing acyclic edge coloring of G. In this paper we prove that if G（V, E） is a graph with no isolated edges, then χ＇αα（G）≤32△.

关键词： Adjacent strong edge coloring adjacent vertex distinguishing acyclic edge coloring adjacent vertexdistinguishing acyclic edge chromatic number the LovNsz local lemma

Effect of clay content to the strength of gravel soil in the source region of debris flow

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Journal of Mountain Science 2018年第10期15卷 2320-2334页

作者： CHEN Ning-sheng gao Yan-chao Yang Cheng-lin HU Gui-sheng Key Laboratory of Mountain Hazards and Land Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 60041China Chengdu Center China Geological SurveyChengdu 610081China University of Chinese Academy of Sciences Beijing 100049China

The production of runoff in the source area of a debris flow is the consequence of a reduction in soil strength. Gravel soil is widely distributed in the source region, and the influence of its clay content on soil strength is one of the important questions regarding the formation mechanism of debris flows. In this paper, the clay content in gravel soil is divided into groups of low clay content(1%, 2, 5%), moderate clay content(3.75%, 5.00%, 6.25%, 7.5%) and high clay content(10.0%, 12.5%, 15%). Tests of the unconsolidated undrained shear strength and consolidated drained shear strength were performed. The unconsolidated undrained shearing(UU) experiment simulates the rapid shear failure of loose gravel soil under the conditions of brief heavy rainfall. The consolidated drained shearing(CD) experiment simulates creep failure of consolidated sediment during extended rainfall. The pore water pressure first increased and then decreased as the clay content increased, and the increase in pore pressure was relatively high in the gravel soil sample when the clay content is in the range of 3.25-7.50%, and stress in the gravel soil is relatively low for a moderate clay content. Gravelly soils with a moderate clay content are moreprone to debris-flow initiation. This paper presents a mathematical formula for the maximum shear stress and clay content of gravel soil under two conditions. The key processes whereby the soil fails and triggers a debris flow—volume contraction of soil, expansion of clay soil, and rise of pore pressure―cause reductions in the soil friction force and enhancement of the water content in the clay particles, and subsurface erosion of soil reduces the soil viscosity, which eventually reduces the soil strength so that the soil loses its stability, liquefies and generates a debris flow.

关键词： Debris flows Gravel soil Clay content Maximum shear stress Pore water pressure

APRS: a privacy-preserving location-aware recommender system based on differentially private histogram

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Science China(Information Sciences) 2017年第11期60卷 297-306页

作者： sheng gao Xindi MA Jianming ZHU Jianfeng MA School of Information Central University of Finance and Economics School of Computer Science and Technology Xidian University School of Cyber Engineering Xidian University

Appendix A Preliminaries In this section,we present some preliminaries that server as the basis of *** convenience,the notations used in this paper are listed in Tabel A1.

关键词： a privacy-preserving location-aware recommender system based on differentially private histogram Si

同方期刊数据库

Magnitude-frequency relationship of debris flows in the Jiangjia Gully, China

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Journal of Mountain Science 2019年第6期16卷 1289-1299页

作者： gao Yan-chao CHEN Ning-sheng HU Gui-sheng DENG Ming-feng Key Laboratory of Mountain Hazards and Land Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 610041China Chengdu Center China Geological SurveyChengdu 610081China University of Chinese Academy of Sciences Beijing 100049China

The magnitude-frequency(MF) relationship of debris flows is the basis for engineering designs and risk quantification. However, because of the lack of debris flow monitoring data, research progress in this area has been relatively slow. The MF relationship of debris flows in Jiangjia Gully, Yunnan Province was evaluated based on a regression analysis of 178 debris flow events that occurred from 1987-2004. The magnitude-cumulative frequency(MCF) relationship of the debris flows in the Jiangjia Gully is consistent with the linear logarithmic transformation function. Moreover, observed data for debris flows in Hunshui Gully of Yunnan Province and Huoshao Gully, Liuwan Gully, and Niwan Gully of Gansu Province were used to verify the function. The results showed that the MCF relationship of highfrequency debris flows is consistent with the power law equation, although the regression coefficients in the equation are considerably different. Further analysis showed a strong correlation between the differences in the constants and the drainage area and daily maximum precipitation.

关键词： Debris flow Magnitude Cumulative frequency Drainage area Precipitation Jiangjia Gully

Remodeling of host membranes during herpesvirus assembly and egress

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Protein & Cell 2019年第5期10卷 315-326页

作者： Ying Lv sheng Zhou shengyan gao Hongyu Deng CAS Key Laboratory of Infection and Immunity Institute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Many viruses,enveloped or non-enveloped,remodel host membrane structures for their replication,assembly and escape from host *** are important human pathogens and cause many *** large enveloped DNA viruses,herpesviruses undergo several complex steps to complete their life cycles and produce infectious ***,herpesvirus assembly initiates in the nucleus,producing nucleocapsids that are too large to cross through the nuclear *** nucleocapsids instead bud at the inner nuclear membrane to form primary enveloped virions in the perinuclear space followed by fusion of the primary envelopes with the outer nuclear membrane,to translocate the nucleocapsids into the ***,nucleocapsids obtain a series of tegument proteins in the cytoplasm and bud into vesicles derived from host organelles to acquire viral *** vesicles are then transported to and fuse with the plasma membrane to release the mature virions to the extracellular ***,at least two budding and fusion events take place at cellular membrane structures during herpesviruses assembly and egress,which induce membrane *** this review,we describe and discuss how herpesviruses exploit and remodel host membrane structures to assemble and escape from the host cell.

关键词： herpesviruses assembly egress budding fusion membrane deformations

T-PBFT: An EigenTrust-Based Practical Byzantine Fault Tolerance Consensus Algorithm

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China Communications 2019年第12期16卷 111-123页

作者： sheng gao Tianyu Yu Jianming Zhu Wei Cai School of Information Central University of Finance of EconomicsBeijing 100081China Grain Information Processing and Control Key Laboratory of Ministry of Education Henan University of TechnologyZhengzhou 450001China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China

Blockchain with these characteristics of decentralized structure, transparent and credible, time-series and immutability, has been considering as a promising technology. Consensus algorithm as one of the core techniques of blockchain directly affects the scalability of blockchain systems. Existing probabilistic finality blockchain consensus algorithms such as PoW, PoS, suffer from power consumptions and low efficiency;while absolute finality blockchain consensus algorithms such as PBFT, HoneyBadgerBFT, could not meet the scalability requirement in a largescale network. In this paper, we propose a novel optimized practical Byzantine fault tolerance consensus algorithm based on EigenTrust model, namely T-PBFT, which is a multi-stage consensus algorithm. It evaluates node trust by the transactions between nodes so that the high quality of nodes in the network will be selected to construct a consensus group. To reduce the probability of view change, we propose to replace a single primary node with a primary group. By group signature and mutual supervision, we can enhance the robustness of the primary group further. Finally, we analyze T-PBFT and compare it with the other Byzantine fault tolerant consensus algorithms. Theoretical analysis shows that our T-PBFT can optimize the Byzantine fault-tolerant rate,reduce the probability of view change and communication complexity.

关键词： blockchain consensus protocol Byzantine fault tolerance trust model

Stochastic Model for Estimating Extreme Water Level in Port and Coastal Engineering Design

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Journal of Ocean University of China 2018年第4期17卷 744-752页

作者： DONG sheng CHEN Chengchao TAO Shanshan gao Junguo College of Engineering Ocean University of China

Extreme water level is an important consideration when designing coastal protection structures. However, frequency analysis recommended by standard codes only considers the annual maximum water level, whereas water levels should actually be regarded as a combination of astronomical tide and storm surge. The two impacting factors are both random variables, and this paper discusses their dependency structures and proposes a new joint probability method to determine extreme design water levels. The lognormal, Gumbel, Weibull, Pearson type 3, traditional maximum entropy, and modified maximum entropy distributions are applied to fit univariate data of astronomical tides and storm surges separately, and the bivariate normal, Gumbel-Hougaard, Frank and Clayton copulas are then utilized to construct their joint probability distributions. To ensure that the new design method is suitable for use with typhoon data, the annual occurrence frequency of typhoon processes is considered and corresponding bivariate compound probability distributions are proposed. Based on maximum water level data obtained from Hengmen hydrological station in the Pearl River Basin, China, these probability models are applied to obtain designs for extreme water levels using the largest sum of the astronomical tide and storm surge obtained under fixed joint return periods. These design values provide an improved approach for determining the necessary height of coastal and offshore structures.

关键词： extreme water level astronomical tide storm surge typhoon copula

An investigation of weed seed banks reveals similar potential weed community diversity among three different farmland types in Anhui Province, China

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Journal of Integrative Agriculture 2019年第4期18卷 927-937页

作者： HE Yun-he gao Ping-lei QIANG sheng Weed Research Laboratory Nanjing Agricultural University School of Landscape Architecture Zhejiang Agricultural & Forestry University

Crop type is one of main factors influencing weed community structure. However, the identity of weed communities associated with the cultivation of different crops in farmlands remains largely unclear. A field survey of weed seed banks was conducted in 2 280 fields at 228 sites of 62 locations representing three different types of farmland(95 paddy, 73 summer-ripe, and 60 autumn-ripe farmlands) along the bank of the Yangtze River in Anhui Province, China. A total of 43 families and 174 species of weeds were found in these weed seed banks. A comparison of the composition of weed groups in the seed banks showed that the species number and density percentage of grass, sedge and broadleaf weed groups were similar among the different types of farmland. The seed banks of all three farmland types shared 71 common weed species, accounting for 40.80% of the total number of species. These common weeds, which were both associated and not associated with crops, accounted for 91.71% of the total dominance degree among all farmland types. The crop-associated weed species were distributed in all soil layers of each farmland type. The Shannon-Wiener index H′(description of species diversity which is more sensitive to dense species) and Pielou's evenness index J(description of species evenness) in summer-ripe farmland were similar to those in autumn-ripe farmland but differed from those in paddy farmland. However, the Simpson's index D(description of species diversity which is more sensitive to sparse species) was similar among all three farmland types. The results of similarity comparison indicated that although the aboveground weed community differed among the different cropping patterns, the weed species composition in the soil seed bank was still similar. Consequently, our results demonstrate that after the implementation of long-term monoculture patterns, weed species compositions in the soil seed bank in different farmlands become homogenized regardless of the crop type.

关键词： species compositi on domi nance degree comm unity similarity comm unity variati on Anhui Province

Failure mode and dynamic response of a double-sided slope with high water content of soil

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Journal of Mountain Science 2018年第4期15卷 859-870页

作者： YANG Bing gao Fu-ping JENG Dong-sheng School of Civil Engineering Southwest Jiaotong University Institute of Mechanics Chinese Academy of Sciences School of Engineering and Built Environment Griffith University Gold Coast Campus

A double-sided slope with high water content in sandy clay was considered under the action of seismic load. Its failure mode and dynamic response were investigated using a hydraulic servo shaking table test. The typical characteristic of failure mode and dynamic responses of the double-sided slope were analyzed. Experimental results show that slope failure undergoes a process of progressive deformation. The slope failure mode can be explained as creep sliding landslide. AFA(Amplification Factor of Acceleration) at the surface and inner parts of the slope shows an increasing trend with the increase of relative elevation. The relationship between AFA and EAA(Excitation Amplitude of Acceleration) is nonlinear. An empirical formula is proposed to describe preferably the relationship between AFA,relative elevation and dimensionless EAA. The AFA at the middle and upper parts of the slope increases apparently with increasing EFA(Excitation Frequency of Acceleration).

关键词： Slope displacement Slope failure mode Soil water content Shaking table test Landslides