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Fractional moments of Automorphic L-Functions on GL(m)

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Chinese Annals of mathematics,series B 2011年第4期32卷 631-642页

作者： Qinghua pi school of mathematics Shandong University Jinan 250100 China.

Let πr be an irreducible unitary cuspidal representation of GL,^（AQ）, m ≥ 2. Assume that π is self-contragredient. The author gets upper and lower bounds of the same order for fractional moments of automorphic L-function L（s, π） on the critical line under Generalized Ramanujan Conjecture; the upper bound being conditionally subject to the truth of Generalized Riemann Hypothesis.

关键词： moments Automorphic L-functions GRC

NANOGrav hints on planet-mass primordial black holes

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science China(Physics,mechanics & Astronomy) 2022年第3期65卷 26-32页

作者： Guillem Domenech shi pi INFN sezione di Padova Padova 1-35131Italy CAs Key'Laboratory of Theoretical Physics.Institute of Theoretical Physics ChinesAcademy of SciencesBeijing 100190China Kavli Institute for the Physics and mathematics of the Universe(Wpi) The University of Tokyo Institutes for Advanced StudyThe University of TokyoKashiwaChiba 277-8583Japan

Recently, the North American Nanohertz Observatory for Gravitational Waves(NANOGrav) claimed the detection of a stochastic common-spectrum process of the pulsar timing array(PTA) time residuals from their 12.5 year data, which might be the first detection of the stochastic background of gravitational waves(GWs). We show that the amplitude and the power index of such waves imply that they could be the secondary GWs induced by the peaked curvature perturbation with a dust-like post inflationary era with-0.091 ≤ w ≤ 0.048. such stochastic background of GWs naturally predicts substantial existence of planet-mass primordial black holes(PBHs), which can be the lensing objects for the ultrashort-timescale microlensing events observed by the Optical Gravitational Lensing Experiment(OGLE).

关键词： pulsar timing array stochastic gravitational waves the early universe

DOEs INVEsTOR sENTImENT PREDICT sTOCK RETURNs? THE EVIDENCE FROm CHINEsE sTOCK mARKET

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Journal of systems science & Complexity 2014年第1期27卷 130-143页

作者： BU Hui pi Li school of Economics and management Beihang University

This paper examines the proxy variables of investor sentiment in Chinese stock market carefully, and tries to construct an investor sentiment index indirectly. We use cross correlation analysis to examine lead-lag relationship between the proxy variables and Hs300 index. The results show that net added accounts （NAA）, ssE share turnover （TURN）, and closed-end fund discount （CEFD） are leading variables to stock market. The average first day return of IPOs （RIPO） and relative degree of active trading in equity market （RDAT） are contemporary variables, while number of IPOs （NIPO） is a lagging variable of stock market. Using the sentiment proxy variables with most possible leading order, and forward selection stepwise regression method, the empirical results on monthly stock returns reveal that three leading proxy variables can be used to form a sentiment index. And the out of sample tests prove that this sentiment index has good predictive power of Chinese stock market, and it is robust.

关键词： Chinese stock market investor sentiment return predictability.

On the Characterization of maximal Planar Graphs with a Given signed Cycle Domination Number

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Acta mathematica sinica,English series 2018年第5期34卷 911-920页

作者： Xiao ming pi Department of mathematics Harbin Normal University

Let G = （V, E） be a simple graph. A function f ： E → {＋1,-1} is called a signed cycle domination function （sCDF） of G if ∑e∈E（C） f（e） ≥ 1 for every induced cycle C of G. The signed cycle domination number of G is defined as γ′sc（G） = min{∑e∈E f（e）｜ f is an sCDF of G}. This paper will characterize all maxima] planar graphs G with order n ≥ 6 and γ′sc（G） =n.

关键词： Domination number signed cycle domination function signed cycle domination number planar graph maximal planar graph

Azimuth space-variant properties of BisAR with nonequal velocities

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Journal of systems Engineering and Electronics 2008年第5期19卷 919-922页

作者： Yang Yonghong pi Yiming school of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

Bistatic sAR possesses characteristic of the azimuth space-variant when the velocities of transmitter and receiver are not equal. The geometric model of BisAR with the parallel trajectories and the nonequal platform velocities is presented. Analyzing the motion relationship of transmitter and receiver, the formula of azimuth spacevariant is derived in time domain. Via Taylor polynomial expansions, the azimuth space-variant is factorized by four terms： zero-order, first-order, second-order, and third-order term. And, their impacts on impulse response are illuminated. some characteristics about azimuth space-variant of airborne BisAR case are exhibited by simulation experiments, and these simulated results are coincident with the formulae of azimuth space-variant.

关键词： bistatic sAR range migration azimuth space-variant imaging formation algorithm.

Investigation of kinetics in bioaugmentation of crude oil via high-throughput sequencing: Enzymatic activities, bacterial community composition and functions

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Petroleum science 2022年第4期19卷 1905-1914页

作者： Yong-Rui pi mu-Tai Bao school of Ocean Yantai UniversityYantai264005China Key Laboratory of marine Chemistry Theory and Technology Ministry of Education/Institute for Advanced Ocean StudyOcean University of China Qingdao266100China

The enzymes and the characteristics of the community of the petroleum-degrading bacteria play a crucial role in the crude oil biodegradation. The prediction of kinetics of the key groups of hydrocarbons in crude oil was important to evaluate the bioremediation speed and constant. most of the n-alkanes(C9-C29) were degraded in 25 days, and the average degradation rates of C_(18)~C_(27) higher than 100 μg g^(-1) d^(-1).The hopanes, such as H_(30), had a biodegradation rate more than 10 μg g^(-1) d^(-1). The related enzymes activities changed along with the crude oil biodegradation, especially dehydrogenase. The 16 s rRNA gene amplicon sequencing revealed that Proteobacteria, Firmcutes, Bacteroidetes, Actinobacteria, Acidobacteria were the main petroleum hydrocarbon degraders during the crude oil biodegradation, and the top two highest relative abundance of the genera were Alcaligenes and Acinetobacter. Acinetobacter presented positive correlation to biodegradation of n-alkanes and PAHs. Based on COG analysis, the largest group involved in the general function was amino acid transport and metabolism. The functional categories of bacterial communities were mainly focused on the carbohydrate and amino acid metabolism, xenobiotics biodegradation and metabolism, membrane transport, and so on. Overall, these findings highlight the potential guideline for more adequate monitoring of microbial degradation of crude oil.

关键词： Crude oil Bioaugmentation Kinetics Enzyme activities microbial functions

Review of computer-generated hologram algorithms for color dynamic holographic three-dimensional display

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Light(science & Applications) 2022年第9期11卷 1962-1978页

作者： Dapu pi Juan Liu Yongtian Wang Beijing Engineering Research Center for mixed Reality and Advanced Display School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China

Holographic three-dimensional display is an important display technique because it can provide all depth information of a real or virtual scene without any special *** recent years,with the development of computer and optoelectronic technology,computer-generated holograms have attracted extensive attention and developed as the most promising method to realize holographic ***,some bottlenecks still restrict the development of computer-generated holograms,such as heavy computation burden,low image quality,and the complicated system of color holographic *** overcome these problems,numerous algorithms have been investigated with the aim of color dynamic holographic three-dimensional *** this review,we will explain the essence of various computer-generated hologram algorithms and provide some insights for future research.

关键词： holographic dynamic overcome

software Reliability Growth model for Imperfect Debugging Process Considering Testing-Effort and Testing Coverage

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 455-463页

作者： Zang sicong pi Dechang College of Computer science and Technology Nanjing University of Aeronautics and Astronautics

Because of the inevitable debugging lag,imperfect debugging process is used to replace perfect debugging process in the analysis of software reliability growth *** neither testing-effort nor testing coverage can describe software reliability for imperfect debugging completely,by hybridizing testing-effort with testing coverage under imperfect debugging,this paper proposes a new model named *** the assumption that the number of faults is proportional to the current number of detected faults,this model combines generalized modified Weibull(GmW)testing-effort function with logistic(LO)testing coverage function,and inherits GmW's amazing flexibility and LO's high fitting ***,the fitting accuracy and predictive power are verified by two series of experiments and we can draw a conclusion that our model fits the actual failure data better and predicts the software future behavior better than other ten traditional models,which only consider one or two points of testing-effort,testing coverage and imperfect debugging.

关键词： software reliability testing-effort testing coverage imperfect debugging(ID) non-homogeneous Poisson process(NHPP)

The mechanism and pathway of the ozonation of 4-chlorophenol in aqueous solution

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science China Chemistry 2006年第4期49卷 379-384页

作者： pi Yunzheng WANG Jianlong Laboratory of Environmental Technology Institute of Nuclear Energy Technology Tsinghua University Beijing 100084 China Laboratory of Environmental Technology Institute of Nuclear Energy Technology Tsinghua University Beijing 100084 China

The removal efficiency of 4-chlorophenol by ozonation was studied, and the reaction mechanism and characteristic of ozonation of 4-chlorophenol were investigated. Ozone and hydroxyl radicals are two strong oxidants during the process of ozonation. The experimental results showed that when there was no scavenger to inhibit OH· radicals, an intermediate product, hydrogen peroxide was formed during the ozonation of 4-chlorophenol. Hydrogen peroxide reacted with ozone at neutral pH and produced hydroxyl radicals. Ozone at the dosage of 113 mg/L could remove 20 mg/L 4-chlorophenol and 39% TOC. With the complete inhibition of hydroxyl radicals, molecular ozone could effectively destroy 4-chlorophenol to form 4-quinone, which was subsequently oxidized to formic acid and oxalic acid. Two reaction pathways of the degradation of 4-chlorophenol by ozone and O3/OH· were proposed in this study. Ozonation is an effective method for reducing 4-chlorophenol, and has potential to practical application.

关键词： 4-chlorophenol, ozone, hydrogen peroxide, 4-quinone, hydroxyl radicals.