Lossless variable-length source coding with codeword cost is considered for general sources. The problem setting, where we impose on unequal costs on code symbols, is called the variable-length coding with codeword co...
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Lossless variable-length source coding with codeword cost is considered for general sources. The problem setting, where we impose on unequal costs on code symbols, is called the variable-length coding with codeword cost. In this problem, the infimum of average codeword cost have already been determined for general sources. On the other hand, the overflow probability, which is defined as the probability of codeword cost being above a threshold, have not been considered yet. In this paper, we first determine the infimum of achievable threshold in the first-order sense and the second-order sense for general sources with additive memoryless codeword cost. Then, we compute it for some special sources such as i.i.d. sources and mixed sources. A generalization of the codeword cost is also discussed.
Recent traffic measurements in corporate local-area networks (LAN's), variable-bit-rate video sources, ISDN control-channels, and other communication systems, have indicated traffic behavior of self-similar nature...
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Recent traffic measurements in corporate local-area networks (LAN's), variable-bit-rate video sources, ISDN control-channels, and other communication systems, have indicated traffic behavior of self-similar nature, This paper first discusses some definitions and propel ties of (second-order) selfsimilarity and gives simpler criteria for it, It then gives a model of self-similar traffic suitable for queuing system analysis of an asynchronous transfer mode (ATM) queue, A lower bound to the overflow probability of a finite ATM buffer is obtained, as also a lower bound to the cell loss probability, Finally, the stationary distribution of the cell delay in an infinite ATM buffer is obtained.
It was recently shown, from real measurements in high-speed communications networks, that network traffic may demonstrate properties of long-range dependency peculiar to the self-similar stochastic process. It was als...
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It was recently shown, from real measurements in high-speed communications networks, that network traffic may demonstrate properties of long-range dependency peculiar to the self-similar stochastic process. It was also shown by measurements that with increasing buffer capacity, the resulting cell loss is not reduced exponentially fast, as it is predicted by queueing theory applied to traditional telecommunication Markovian models, but in contrast, decreases very slowly. The problem is how to present a theoretical understanding to those experimental phenomena. The paper presents mathematical models for self-similar cell traffic and analyzes the overflow behavior of a finite-size ATM buffer fed by such a traffic. An asymptotical upper bound to the overflow probability, which decreases hyperbollically, h(-a), with buffer size h is obtained. The lower bound given in Tsybakov and Georganas (1997) and the upper bound obtained here demonstrate the same h(-a) asymptotical behavior, thus showing the actual hyperbolical decay of overflow probability for a self-similar-traffic model. (C) 1998 Elsevier Science B.V.
In this letter, we generalize the achievability of variable-length coding from two viewpoints. One is the definition of an overflow probability, and the other is the definition of an achievability. We define the overf...
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In this letter, we generalize the achievability of variable-length coding from two viewpoints. One is the definition of an overflow probability, and the other is the definition of an achievability. We define the overflow probability as the probability of codeword length, not per symbol, is larger than eta(n) and we introduce the epsilon-achievability of variable-length codes that implies an existence of a code for the source under the condition that the overflow probability is smaller than or equal to epsilon. Then we show that the epsilon-achievability of variable-length codes is essentially equivalent to the epsilon-achievability of fixed-length codes for general sources. Moreover by using above results, we show the condition of epsilon-achievability for some restricted sources given epsilon.
Flooding from the overflow of rivers and streams can cause major disruption in urban areas that is likely to have significant effects on human activities and the environment. Such consequences could be exacerbated by ...
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Flooding from the overflow of rivers and streams can cause major disruption in urban areas that is likely to have significant effects on human activities and the environment. Such consequences could be exacerbated by enhanced levels of precipitation resulting from future climate change. Various options are available for responding to flooding;however, further studies are needed to improve the design flood criteria in order to cope with the uncertainties of a changing climate. This study investigated an improved methodology for the evaluation of the overflow probability of urban streams. This was achieved through the application of Monte Carlo simulations (MCSs) and climate change scenarios that incorporated an increased probability of overbank flooding. An estimation of the probability of future rainfall in the Uicheon Basin of Korea, using chaos disintegration with regional climate model (RCM) scenario data, indicated a projected increase of 4.4%-9.6%. The results for 100-year flooding under projected conditions of climate change, based on a hydrologic overflow inundation model, showed that flooded areas could increase by 58.1% compared with current levels, depending on the climate change scenarios. However, forecasts based on MCSs indicated that extreme rainfall could increase by 94.9%. Thus, an overflow analysis that reflects both extreme hydrologic events and more frequent flooding due to climate change could provide a more reliable means of forecasting extreme events, as well as helping to prevent natural disasters associated with unexpected extreme flooding. The results obtained in this study would provide useful data for stakeholders and decision makers to both enhance policy standards and formulate measures to reduce the risk of urban flooding within the context of a changing climate. (C) 2015 International Association for Hydro-environment Engineering and Research, Asia Pacific Division. Published by Elsevier B.V. All rights reserved.
In this paper we study the asymptotic relationship between the loss ratio in a finite buffer system and the overflow probability (the tail of the queue length distribution) in the corresponding infinite buffer system....
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In this paper we study the asymptotic relationship between the loss ratio in a finite buffer system and the overflow probability (the tail of the queue length distribution) in the corresponding infinite buffer system. We model the system by a fluid queue which consists of a server with constant rate c and a fluid input. We provide asymptotic upper and lower bounds on the difference between log P {Q > x} and log P-L (x) under different conditions. The conditions for the upper bound are simple and are satisfied by a very large class of input processes. The conditions on the lower bound are more complex but we show that various classes of processes such as Markov modulated and ARMA type Gaussian input processes satisfy them.
The overflow probability is one of criteria that evaluate the performance of fixed-to-variable length (FV) codes. In the single source coding problem, there were many researches on the overflow probability. Recently, ...
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The overflow probability is one of criteria that evaluate the performance of fixed-to-variable length (FV) codes. In the single source coding problem, there were many researches on the overflow probability. Recently, the source coding problem for correlated sources, such as Slepian-Wolf coding problem or source coding problem with side information, is one of main topics in information theory. In this paper, we consider the source coding problem with side information. In particular, we consider the FV code in the case that the encoder and the decoder can see side information. In this case, several codes were proposed and their mean code lengths were analyzed. However, there was no research about the overflow probability. We shall show two lemmas about the overflow probability. Then we obtain the condition that there exists a FV code under the condition that the overflow probability is smaller than or equal to some constant.
This paper presents an approximation formula for the overflow probability for GI/GI/c(N) queues in terms of a queue-length distribution for the corresponding GI/GI/c (infinity) queues, where N is the total capacity of...
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This paper presents an approximation formula for the overflow probability for GI/GI/c(N) queues in terms of a queue-length distribution for the corresponding GI/GI/c (infinity) queues, where N is the total capacity of the system. The approximation is based on the conservation law, and on assumptions which might be acceptable if N much greater than c. The authors' approximation formula is numerically examined for various phase-type GI/GI/c(N) queues and the results show that the approximation is very good for practical parameter settings. The authors' approximation stands merely on a stationarity assumption. Therefore, it is also expected to be good for G/G/c(N) queues with a large N.
In this paper we consider Mamdani fuzzy inference system to study for optimizing the buffer overflow probability in a single M/M/1 queue and two M/M/1 queue in tandem Jackson networks. Mamdani fuzzy inference system i...
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ISBN:
(纸本)9781479932641
In this paper we consider Mamdani fuzzy inference system to study for optimizing the buffer overflow probability in a single M/M/1 queue and two M/M/1 queue in tandem Jackson networks. Mamdani fuzzy inference system is proposed to estimate the service rate for the Jackson queueing network. The arrival rate and the highest overflow level of a particular queue are provided to the Mamdani fuzzy inference system which generates the service rate according to the fuzzy rule base. The arrival rate, the highest overflow level and the new service rate will be used to estimate the buffer overflow in a single M/M/1queueing network then in two queues in tandem queueing network. Simulation results shows that Mamdani fuzzy inference system reduce the buffer overflow probability as compared with the normal estimation of buffer overflow probability.
We consider the source coding problem with side information. Especially, we consider the FV code in the case that the encoder and the decoder can see side information. We obtain the condition that there exists a FV co...
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ISBN:
(纸本)9780769539942
We consider the source coding problem with side information. Especially, we consider the FV code in the case that the encoder and the decoder can see side information. We obtain the condition that there exists a FV code under the condition that the overflow probability is smaller than or equal to some constant.
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