The proposed model composes the strongpoints of the centralized in and distributed in , and the corresponding load controlling algorithm contains overload control and route control , which come from the analyses of the queuing model , the call model , and the call processing procedure in the multi - scps in 該模型是通過深入分析多scp智能網(wǎng)排隊(duì)模型、多scp智能網(wǎng)呼叫模型和典型的呼叫處理過程的基礎(chǔ)上得出的,其負(fù)載控制算法包括過載控制和路由控制兩部分,融合了集中式和分布式智能網(wǎng)的優(yōu)點(diǎn)。
First of all , we have established models of microcosmic traffic flow , such as : car _ send out model , car _ dynamical model , following model , changing driveway model , queuing model , toll station model , adding and diverting traffic flow model , car _ arriving model , model of basic road , net of road model , etc . then i have programmed modules of all models , and determined the method of system simulation 本文主要立足與高速公路微觀交通流仿真系統(tǒng)的建模與實(shí)現(xiàn),首先確立微觀交通流各仿真模型,如:發(fā)車模型,車輛運(yùn)動(dòng)模型,跟馳模型,換車道模型,排隊(duì)模型,收費(fèi)站模型,匝道合流與分流模型,車輛到達(dá)消失模型,基本道路模型,路網(wǎng)仿真模型等。然后編制各模型的實(shí)現(xiàn)模塊,確定系統(tǒng)的仿真方法。
We then consider the n policy m / g / 1 queueing model with two priorities . by using the supplementary variable method to analyze the state probability equations , we derive the generating function of queueing length distribution and the mean queue length in the buffer of the communications network . and through further discussing for the queue with various priorities , we derive the generating function of queueing length distribution and the stationary queueing length in queue models with various priorities 其次研究帶有兩個(gè)優(yōu)先權(quán)的n策略m g 1排隊(duì)模型,利用補(bǔ)充變量法對狀態(tài)概率方程組進(jìn)行分析,得出了此排隊(duì)系統(tǒng)隊(duì)長分布母函數(shù)及通信網(wǎng)緩沖器中的平均隊(duì)長,并對不同優(yōu)先權(quán)隊(duì)列的進(jìn)一步討論,得出了不同優(yōu)先權(quán)隊(duì)列的隊(duì)長分布母函數(shù)及穩(wěn)態(tài)隊(duì)長。
When studying the network performance , flow control and resource provisioning of communication networks , traffic model plays a very important role . the recent studies show that the date network traffic is self - similar , so the markovian model , which describes telephone networks accurately , is not suitable for date networks . the self - similarity of the network traffic has severe impact on flow control and queuing analysis in date networks , therefore it has received significant attention . in this paper , g m 1 queuing model is used to analyze the queuing performance of generic variable length packet networks for the first time . the self - similar traffic is generated by multiplexing a large set of independent pareto heavy - tailed interarrival on off sources . the simulation results show that the heavy - tailed traffic results in queuing performance deterioration for variable length packet networks , which is in accordance with the analytical results for atm switches 業(yè)務(wù)量的自相似特征顯著影響網(wǎng)絡(luò)的流量控制與排隊(duì)分析,已經(jīng)引起人們的極大重視。采用g m 1排隊(duì)模型對分組長度可變的網(wǎng)絡(luò)的排隊(duì)性能進(jìn)行了分析和仿真,其中自相似業(yè)務(wù)量是通過疊加大量獨(dú)立的到達(dá)間隔為pareto重尾分布的on off源來生成的。仿真結(jié)果表明,自相似業(yè)務(wù)量導(dǎo)致網(wǎng)絡(luò)的排隊(duì)性能劣化,這與有關(guān)文獻(xiàn)對atm交換的分析結(jié)果一致。
In the chapter 4 , we make an extension to the model of the chapter - 2 . the service speed change is instant , that is say , during the service using speed - 1 to serve , if the number exceeds the threshold n , then the server should immediately use speed - 2 not speed - 1 to serve current customer and the next till entered the empty state . we especially point out that the classical m / g / 1 queuing model and the m / g / 1 queuing with n - policy are the particular cases of model discussed in chapter - 4 第四章對第二章討論的模型進(jìn)行了進(jìn)一步的擴(kuò)展,其服務(wù)速度1到速度2的轉(zhuǎn)移規(guī)則是瞬間轉(zhuǎn)移,也即當(dāng)服務(wù)臺(tái)以速度1服務(wù)顧客的過程中如發(fā)現(xiàn)系統(tǒng)中的顧客數(shù)已超過門限n值時(shí)就即刻調(diào)整為以速度2服務(wù)當(dāng)前顧客和后續(xù)顧客直到系統(tǒng)變空的可修m g ( m g ) 1排隊(duì)系統(tǒng),并指出經(jīng)典的m g 1和具有n -策略的m g 1排隊(duì)是本章研究的兩種特例。
At last , the service performance of the middleware is analyzed . aimed at the analysis and optimization for the service performance of middleware , the nonpreemptive priority m / m n queue model and analyses on the queue length , wait time , remain time and service window are presented . a general method and a set of algorithms for the analysis and optimization are also proposed 最后,從消息排隊(duì)的角度對中間件系統(tǒng)模型進(jìn)行了抽象,針對中間件服務(wù)能力建立了多優(yōu)先級(jí)非搶占m m n隊(duì)列模型,對中間件系統(tǒng)的排隊(duì)隊(duì)列長度、消息等待時(shí)間、消息逗留時(shí)間、服務(wù)窗口數(shù)等指標(biāo)進(jìn)行了深入分析,并給出了一套完整的對中間件服務(wù)能力進(jìn)行分析與優(yōu)化的通用方法和計(jì)算公式。
3 , 4 , 5 and ? 6 of this chapter deal respectively with the transient distribution of the queue length of these four queueing systems . such results are obtained as follows : under the condition of the interarrival times distributions and service times distributions of these queueing models which have density function , their transient distribution of the queue length can be represented as an integral , and the integrated term of this integral can be recursively obtained 在這一章的夸3 、芬4 、縣5和號(hào)6中,分別針對這四個(gè)排隊(duì)模型,討論了瞬時(shí)隊(duì)長的分布,最終得到了以下的結(jié)果:在這幾個(gè)模型的到達(dá)間隔分布和服務(wù)時(shí)間分布均具有密度函數(shù)的條件下,它們的瞬時(shí)隊(duì)長分布可以表示為一個(gè)積分,該積分的被積項(xiàng)可以遞歸地求取。