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Prediction of the solidification structure of casting and heterogeneous nucleation

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Journal of University of Science and Technology Beijing 2003年第3期10卷 43-46页

作者： K.Ohsasa H.Shirosawa T.Narita Hokkaido University Kita-kuSapporo 060-8626JapanHokkaido UniversityKita-kuSapporo 060-8626JapanHokkaido UniversityKita-kuSapporo 060-8626Japan

The frequency of heterogeneous nucleation during the solidification of Al-Sibinary alloy was estimated by comparing experimentally obtained macrostructures of castings withnumerically simulated ones. A molten alloy was unidirectionally solidified from a water-cooledcopper chill in an adiabatic mold. The location of columnar to equiaxed transition (CET) in thesolidified alloy ingot was measured. A numerical simulation for grain structure formation based onthe Monte Carlo method was carried out, and the frequency of heterogeneous nucleation in the alloywas evaluated by producing similar structure with the experimental one. The frequency ofheterogeneous nucleation was expressed as a probabilistic function with an exponential form ofundercooling that deter-mines the probability of nucleation event in the simulation. The value ofthe exponent is regarded as the nucleation parameter. The nucleation parameter of Al-Si binary alloyvaried with initial Si content.

关键词： Al-Si binary alloy nucleation prediction of macro structure probabilistic method

Lower Bounds of Size Ramsey Number for Graphs with Small Independence Number

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 841-846页

作者： Chun-lin YOU Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108 China

Let r≥3 be an integer such that r−2 is a prime power and let H be a connected graph on n vertices with average degree at least d andα(H)≤βn,where 0nd2(r−2)2−Cn−−√for all sufficiently large n,where C is a constant depending only on r,d andβ.In particular,for integers k≥1,and r≥3 such that r−2 is a prime power,we have that there exists a constant C depending only on r and k such that R^(Pkn;r)>kn(r−2)2−Cn−−√−(k2+k)2(r−2)2 for all sufficiently large n,where P k n is the kth power of Pn.

关键词： size ramsey number affine plane probabilistic method

probabilistic Constructions of B_2[g] Sequences

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Acta Mathematica Sinica,English Series 2010年第7期26卷 1309-1314页

作者： Javier CILLERUELO Instituto de Ciencias Matermáticas(CSIC-UAM-UCM) Department of Mathematics Universidad Autónoma de Madrid

We use the probabilistic method to prove that for any positive integer g there exists an infinite B2[g] sequence A = {ak} such that ak ≤ k^2＋1/g（log k）^1/g＋0（1） as k→∞. The exponent 2＋1/g improves the previo... 详细信息

关键词： Sidon sets B2 [g] sequences probabilistic method

Non-homogeneous Tb Theorem for Bi-parameter g-function

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Acta Mathematica Sinica,English Series 2018年第9期34卷 1445-1459页

作者： Ming Ming CAO Qing Ying XUE School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education

The main result of this paper is a bi-parameter Tb theorem for Littlewood-Paley g-function, where b is a tensor product of two pseudo-accretive function. Instead of the doubling measure, we work with a product measure μ = μn × μm, where the measures μn and μm are only assumed to be upper doubling. The main techniques of the proof include a bi-parameter b-adapted Haar function decomposition and an averaging identity over good double Whitney regions. Moreover, the non-homogeneous analysis and probabilistic methods are used again.

关键词： Bi-parameter square function probabilistic method b-adapted Haar functions

A Note on the Existence of Fractional f-factors in Random Graphs

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 677-680页

作者： Jian-sheng CAI Xiao-yang WANG Gui-ying YAN School of Mathematics and Information Science Weifang University Beijing Anzhen Hospital Capital Medical University Academy of Mathematics and System Science Chinese Academy of Science

Let G ： Gn,p be a binomial random graph with n vertices and edge probability p = p（n）, and f be a nonnegative integer-valued function defined on V（G） such that 0 〈 a ≤ f（x） ≤ b 〈 np- 2√nplogn for every E V（G）. An fractional f-indicator function is an function h that assigns to each edge of a graph G a number h（e） in [0, 1] so that for each vertex x, we have d^hG（x） = f（x）, where dh（x） = ∑ h（e） is the fractional degree xEe ofx inG. Set Eh = {e ： e e E（G） and h（e） ≠ 0}. IfGh isaspanningsubgraphofGsuchthat E（Gh） = Eh, then Gh is called an fractional f-factor of G. In this paper, we prove that for any binomial random graph Gn,p 2 with p 〉 n^-2/3, almost surely Gn,p contains an fractional f-factor.

关键词： random graph probabilistic method f-factor fractional f-factor

Estimating the expected value of multiple prospects in bidding blocks

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Energy Geoscience 2022年第3期3卷 263-269页

作者： Jun Li Xuebin Huang Petroleum Exploration and Production Research Institute SINOPECBeijing100083China

In recent years,China has accelerated the reform of its oil and gas management system,especially in competitive transfer of mining *** the expected value(EV)of lease blocks is crucial for the bidding decision of oil *** bidding for a block with several individual prospects,the simple addition of each prospect EV usually leads to overly high and optimistic resource volume and value *** the assessment of the EV of a multi-prospect block,two factors should be ***,the geological setting of the prospects,including their relative spatial relationship,their chance of geological success,their resources and their geological dependency,*** second factor is the exploration strategy of oil companies,concerned with the dry hole tolerance,the committed wells and the drilling priorities for the prospects,etc.A probabilistic method to assess the EV of a multi-prospect block is proposed,which proves to be favorable for formulating a bidding strategy for oil *** addition,a case study on two specific blocks with several prospects is presented to illustrate the effect of the above mentioned factors on the EV.

关键词： Expected value(EV) Multiple prospects Bidding block probabilistic method

probabilistic QOS Aware Congestion Control in Wireless Multimedia Sensor Networks

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Circuits and Systems 2016年第9期7卷 2081-2094页

作者： Muthuselvi Mayandi Kavitha Velayudhan Pillai Department of Computer Science and Engineering University College of Engineering Nagercoil Anna University Chennai India Department of Computer Science and Engineering University College of Engineering Kancheepuram Anna University Chennai India

The general problem faced in the field of Wireless Multimedia Sensor Networks (WMSNs) is congestion. The most common method in the area of WMSNs to minimize congestion is traffic control. Quality Of Service (QOS) is widely used in WMSNs to guarantee preferential service for critical applications by controlling end-to-end delay, reducing data loss and by providing adequate bandwidth. The present work is on probabilistic QOS Aware Congestion Control (PQACC) which employs probabilistic method based congestion prediction and priority based data transmission rate adjustment, where inelastic real-time traffic and elastic non-real-time traffic are treated separately. Using the present PQACC approach, average throughput, average source-to-sink delay and average packet loss probability are improved by 9%, 10.33% and 16.03% compared to EWPBRC and achieved 5.97%, 7.05% and 11.69% improvement compared to FEWPBRC. Simulation result reveals that, congestion is effectively predicted, controlled and provides necessary level of QOS in terms of delay, throughput and packet loss, hence making this approach possible in mission critical applications.

关键词： Congestion Control WMSN Traffic Control QOS probabilistic method Inelastic Traffic Elastic Traffic

非齐次抛物型方程的随机Dirichlet问题(1)(英文)

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哈尔滨工业大学学报 1993年第2期 119-123页

作者：邢振祥王勇哈尔滨工业大学数学系

The classical Dirichlet problem requires very strict boundary conditions(***-

关键词： Stochastic Dirichlct problem probabilistic method