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Open synchronous cellular learning automata
, Article Advances in Complex Systems ; Volume 10, Issue 4 , 2007 , Pages 527-556 ; 02195259 (ISSN) ; Meybodi, M. R ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2007
Abstract
Cellular learning automata is a combination of learning automata and cellular automata. This model is superior to cellular learning automata because of its ability to learn and also is superior to single learning automaton because it is a collection of learning automata which can interact together. In some applications such as image processing, a type of cellular learning automata in which the action of each cell in the next stage of its evolution not only depends on the local environment (actions of its neighbors) but it also depends on the external environments. We call such a cellular learning automata as open cellular learning automata. In this paper, we introduce open cellular learning...
A mathematical framework for cellular learning automata
, Article Advances in Complex Systems ; Volume 7, Issue 3-4 , 2004 , Pages 295-319 ; 02195259 (ISSN) ; Meybodi, M. R ; Sharif University of Technology
2004
Abstract
The cellular learning automata, which is a combination of cellular automata, and learning automata, is a new recently introduced model. This model is superior to cellular automata because of its ability to learn and is also superior to a single learning automaton because it is a collection of learning automata which can interact with each other. The basic idea of cellular learning automata, which is a subclass of stochastic cellular learning automata, is to use the learning automata to adjust the state transition probability of stochastic cellular automata. In this paper, we first provide a mathematical framework for cellular learning automata and then study its convergence behavior. It is...
Asynchronous cellular learning automata
, Article Automatica ; Volume 44, Issue 5 , 2008 , Pages 1350-1357 ; 00051098 (ISSN) ; Meybodi, M. R ; Sharif University of Technology
2008
Abstract
Cellular learning automata is a combination of cellular automata and learning automata. The synchronous version of cellular learning automata in which all learning automata in different cells are activated synchronously, has found many applications. In some applications a type of cellular learning automata in which learning automata in different cells are activated asynchronously (asynchronous cellular learning automata) is needed. In this paper, we introduce asynchronous cellular learning automata and study its steady state behavior. Then an application of this new model to cellular networks has been presented. © 2008
Extract Non-Line-of-Sight state of base stations and error mitigation technique for wireless localization in micro-cell networks
, Article Computer Communications ; Volume 35, Issue 7 , 2012 , Pages 885-893 ; 01403664 (ISSN) ; Golmohammadi, S ; Shadi, K ; Sharif University of Technology
2012
Abstract
Non Line of Sight (NLOS) propagation is a challenging issue which the performance of network based wireless localization is limited by errors primarily caused by NLOS corruption. NLOS is inherently a dominant source of errors in metropolitan area wireless networks, like cellular one, so in this paper we discuss our proposed algorithm within cellular network terminology. This paper contributes two novel algorithms. The first one is to extract the NLOS state of base station (BS) and the second one is a correction algorithm to enhance the measurements accuracy. Our proposed algorithm discuses a novel localization technique to estimate true mobile terminal (MT) location from a set of possibly...
Cellular learning automata based dynamic channel assignment algorithms
, Article International Journal of Computational Intelligence and Applications ; Volume 8, Issue 3 , 2009 , Pages 287-314 ; 14690268 (ISSN) ; Meybodi, M. R ; Sharif University of Technology
2009
Abstract
A solution to channel assignment problem in cellular networks is self-organizing channel assignment algorithm with distributed control. In this paper, we propose three cellular learning automata based dynamic channel assignment algorithms. In the first two algorithms, no information about the status of channels in the whole network will be used by cells for channel assignment whereas in the third algorithm, the additional information regarding status of channels may be gathered and then used by cells in order to allocate channels. The simulation results show that by using the proposed channel assignment algorithms the micro-cellular network can self-organize itself. The simulation results...
Cavitation During Creep Deformation in AA7075-T76: Cellular Automata Simulation and Experiments
, Article Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science ; Volume 52, Issue 9 , 2021 , Pages 4146-4160 ; 10735623 (ISSN) ; Serajzadeh, S ; Sharif University of Technology
Springer
2021
Abstract
In this work, cavitation during creep in AA7075-T76 was simulated employing a probabilistic cellular automata scheme. Two-dimensional cellular automata coupled with the governing equations for cavity growth were utilized to define the size and distribution of cavities during creep. Both diffusion and strain-controlled mechanisms were taken into account while the first and second neighboring cells were considered for determination of the cavity growth as well as to generate the initial microstructure. Moreover, uni-axial creep experiments on AA7075-T76 were carried out under different temperatures and applied stresses including 170 MPa at 150 °C and 150 MPa at 160 °C. The microstructural...
An adaptive filter for noise cancelling in mammography images based on Cellular Automata
, Article International Review on Modelling and Simulations ; Volume 5, Issue 3 , June , 2012 , Pages 1322-1326 ; 19749821 (ISSN) ; Masoumzadeh Tork, A ; Yazdan Talab, E ; Ramezanpour, H ; Darmani, G ; Sharif University of Technology
2012
Abstract
In recent years, several techniques based on repetition of the image are used to remove noise. In this paper a new method based on Cellular Automata for image noise removal in mammography images is recommended. We present a new formulation that makes improvements. The formulation uses a neighborhood with sizes and format adapted to the features of the image on reconstruction. We demonstrated through experiments and comparison with other common used techniques that this procedure produces excellent results for the problem of restoring true color images
Collaboration alignment in distributed interference management in uplink cellular systems
, Article 2016 IEEE International Symposium on Information Theory, 10 July 2016 through 15 July 2016 ; Volume 2016-August , 2016 , Pages 1456-1460 ; 21578095 (ISSN) ; 9781509018062 (ISBN) ; Maddah Ali, M. A ; Shariatpanahi, S. P ; Khalaj, B. H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
Abstract
We consider a cellular wireless system including several interfering multi-user multi-antenna uplink channels, where the base station of each cell has to locally recover the messages of its corresponding users. We use a linear Wyner model, where each base station experiences interference only from the users in the two neighboring cells. Each base station is connected to the two nearby base stations through a backhaul link. The objective is to achieve the maximum degrees of freedom per cell, with minimum aggregated load in the backhaul. We propose a successive cooperative alignment scheme, in which each base station forms backhaul messages by combining the previous received backhaul messages...
Adverse effect of red light violation (RLV) in urban signalized intersections in iran
, Article International Journal of Civil Engineering ; Volume 15, Issue 8 , 2017 , Pages 1107-1116 ; 17350522 (ISSN) ; Nassiri, H ; Sharif University of Technology
Abstract
One of the frequent aspects of lawlessness at signalized intersections is red light violation (RLV). In addition to adverse effects on intersection safety, RLV can cause delay in the startup of the vehicles in the competing phase, defined as the green flow in this study. In this research, a video camera was used to collect the required data from intersections to investigate the adverse effect of RLV in the city of Esfahan, Iran. Then, by assigning a cellular network to the conflict points of the vehicles path in successive phases, the vehicles arrival times to these cells were measured and the imposed delays to the green flow were measured. The results of this study showed that the behavior...
Investigation of phase diagrams for cylindrical Ising nanotube using cellular automata
, Article Physics Letters, Section A: General, Atomic and Solid State Physics ; Volume 382, Issue 19 , May , 2018 , Pages 1291-1297 ; 03759601 (ISSN) ; Ghaemi, M ; Afzali, K ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Recent developments in the field of applied nanoscience and nanotechnology have heightened the need for categorizing various characteristics of nanostructures. In this regard, this paper establishes a novel method to investigate magnetic properties (phase diagram and spontaneous magnetization) of a cylindrical Ising nanotube. Using a two-layer Ising model and the core-shell concept, the interactions within nanotube has been modelled. In the model, both ferromagnetic and antiferromagnetic cases have been considered. Furthermore, the effect of nanotube's length on the critical temperature is investigated. The model has been simulated using cellular automata approach and phase diagrams were...
Cellular learning automata with multiple learning automata in each cell and its applications
, Article IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics ; Volume 40, Issue 1 , 2010 , Pages 54-65 ; 10834419 (ISSN) ; Meybodi, M. R ; Sharif University of Technology
2010
Abstract
The cellular learning automaton (CLA), which is a combintion of cellular automaton (CA) and learning automaton (LA), is introduced recently. This model is superior to CA because of its ability to learn and is also superior to single LA because it is a collection of LAs which can interact with each other. The basic idea of CLA is to use LA to adjust the state transition probability of stochastic CA. Recently, various types of CLA such as synchronous, asynchronous, and open CLAs have been introduced. In some applications such as cellular networks, we need to have a model of CLA for which multiple LAs reside in each cell. In this paper, we study a CLA model for which each cell has several LAs....
Downlink resource allocation for autonomous infrastructure-based multihop cellular networks
, Article Eurasip Journal on Advances in Signal Processing ; Volume 2009 , 2009 ; 16876172 (ISSN) ; Sousa, E. S ; Sharif University of Technology
2009
Abstract
Considering a multihop cellular system with one relay per sector, an effective modeling for the joint base-station/relay assignment, rate allocation, and routing scheme is proposed and formulated under a single problem for the downlink. This problem is then formulated as a multidimensional multichoice knapsack problem (MMKP) to maximize the total achieved throughput in the network. The well-known MMKP algorithm based on Lagrange multipliers is modified, which results in a near-optimal solution with a linear complexity. The notion of the infeasibility factor is also introduced to adjust the transmit power of base stations and relays adaptively. To reduce the complexity, and in order to...
Cache-Aided interference management in wireless cellular networks
, Article IEEE Transactions on Communications ; Volume 67, Issue 5 , 2019 , Pages 3376-3387 ; 00906778 (ISSN) ; Maddah Ali, M. A ; Salman Avestimehr, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
We consider the problem of interference management in wireless cellular networks with caches at both base stations and receivers, and we characterize the degrees of freedom (DoFs) per cell to within an additive gap of (1/3) and a multiplicative gap of 2 for all system parameters, under one-shot linear schemes. Our result indicates that the one-shot linear DoF per cell scales linearly with the total amount of cache available in the cell, i.e., the sum of the caches at the central base station and all the receivers within the cell, resembling a similar phenomenon previously observed for the case of fully connected wireless networks. To establish the result, we propose a decentralized and...
Frequency planning of GSM cellular communication network in urban areas including traffic distribution, a practical implementation
, Article 2008 Asia-Pacific Symposium on Electromagnetic Compatibility and 19th International Zurich Symposium on Electromagnetic Compatibility, APEMC 2008, Suntec, 19 May 2008 through 23 May 2008 ; 2008 , Pages 891-894 ; 9810806280 (ISBN); 9789810806286 (ISBN) ; Farzaneh, F ; Sharif University of Technology
2008
Abstract
Using an in-house developed software the signal level, the best server cells, and the amount of interference using standard propagation models are determined in a cellular environment. The program is also able to assign the frequency channels automatically to the TRXs taking into account the carrier to interference and the traffic distribution using a genetic algorithm. In this paper, the cost function is based on the total Carrier to Interference ratio (C/I) and the traffic density of the serving area. The software by means of a genetic algorithm approaches a frequency assignment which increases the overall quality of service throughout the cellular network. The package has been used in a...
Lower and upper bounds for throughput capacity of a cognitive ad hoc network overlaid on a cellular network
, Article 2008 IEEE Wireless Communications and Networking Conference, WCNC 2008, Las Vegas, NV, 31 March 2008 through 3 April 2008 ; 2008 , Pages 2759-2764 ; 15253511 (ISSN) ; 9781424419968 (ISBN) ; Ashtiani, F ; Sharif University of Technology
2008
Abstract
In this paper, we compute lower and upper bounds for the throughput capacity of an ad hoc network overlaid on a cellular network. The ad hoc network is comprised of a specific number of wireless cognitive nodes that opportunistically exploit the inactive frequency channels in the cellular network. In this respect, we employ a model recently proposed for single-channel mobile ad-hoc network after some minor modifications. The proposed framework consists of two queueing networks, a closed BCMP queueing network comprised of M/G/∞nodes capable of mobility modeling, and an open BCMP queueing network comprised of symmetric M/G/1 nodes capable of modeling the packet transmission process. By...
Determining Mode of Travel Using Cell Phone Data
, M.Sc. Thesis Sharif University of Technology ; Shafahi, Yousef (Supervisor)
Abstract
There has been growing interest in exploiting cellular network data for transportation planning purposes in recent years. In this thesis, we utilize these data for determining mode of travel in the city of Shiraz, Iran. Cellular data records -including location updates in 5minute time intervals- of 300,000 users from the city of Shiraz has been collected for 40 hours in three consecutive days in a cooperation with the major telecommunications service provider of the country. Depending on the density of mobile BTS’s in different zones of the city, the user location can be located within an average of 200 meters. Considering data filtering and smoothing, data preparation and converting them to...
Coded caching with small subpacketization via spatial reuse and content base replication
, Article 2019 IEEE International Symposium on Information Theory, ISIT 2019, 7 July 2019 through 12 July 2019 ; Volume 2019-July , 2019 , Pages 2982-2986 ; 21578095 (ISSN) ; 9781538692912 (ISBN) ; Caire, G ; The Institute of Electrical and Electronics Engineers, Information Theory Society ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In the context of coded caching in a K-user, L-cells cellular network, we show that by using a simple decentralized content base replication scheme and exploiting spatial reuse, a very good file delivery throughput with small file subpacketization order can be achieved. In particular, this is close to the throughput achieved in a L-servers linear network or L-antenna fully connected MIMO network (up to a multiplicative factor that depends mainly on the cellular frequency reuse), where the coded caching gain and the L-fold spatial multiplexing act additively. This is another manifestation of the fact that spatial reuse is a key approach to tackle the subpacketization order problem of coded...
Cellular design for a dense RFID reader environment
, Article APCCAS 2008 - 2008 IEEE Asia Pacific Conference on Circuits and Systems, Macao, 30 November 2008 through 3 December 2008 ; January , 2008 , Pages 1124-1127 ; 9781424423422 (ISBN) ; Bakhtiar, M. S ; Atarodi, M ; Sharif University of Technology
2008
Abstract
This paper presents a method for positioning a large number of readers in an RFID cellular deployment zone while taking advantage of frequency and time domain multiplexing. The safe distance among the readers in the proposed cellular structure is calculated considering features such as collisions, local regulations and propagation issues. Using hexagonal cells, the RFID readers and tags are placed in an assumptive environment such as a warehouse building or a supermarket and the reliability of the implementation is estimated by means of calculating the total Bit Error Rate (BER). © 2008 IEEE
Modelling drivers' behaviour as a crash risk reduction process
, Article Promet - Traffic - Traffico ; Volume 20, Issue 3 , Volume 20, Issue 3 , 2008 , Pages 139-146 ; 03535320 (ISSN) ; Vaziri, M ; Sharif University of Technology
Faculty of Transport and Traffic Engineering
2008
Abstract
The evermore widespread use of microscopic traffic simulation in the analysis of road systems has refocused attention on sub models, including car-following and lane-changing models. In this research a microscopic model is developed which combines car-following and lane-changing models and describes driver behaviour as a crash risk reduction process of drivers. This model has been simulated by a cellular automata simulator and compared with the real data. It has been shown that there is no reason to consider the model invalid for drivers' behaviour in the basic segments of freeways in Iran, during not-congested conditions. Considering that uncertainty of position of vehicles is caused by...
Applying simulated annealing to cellular manufacturing system design
, Article International Journal of Advanced Manufacturing Technology ; Volume 32, Issue 5-6 , 2007 , Pages 531-536 ; 02683768 (ISSN) ; Saidi, M ; Abbasi, B ; Sharif University of Technology
2007
Abstract
Cell formation and cellular layout design are the two main steps in designing a cellular manufacturing system (CMS). In this paper, we will present an integrated methodology based on a new concept of similarity coefficients and the use of simulated annealing (SA) as an optimization tool. In comparison with the previous works, the proposed methodology takes into account relevant production data, such as alternative process routings and the production volumes of parts. The SA-based optimization tool is parallel in nature and, hence, can reduce the computation time significantly, so it is capable of handling large-scale problems. Finally, the SA-based procedure is compared with a genetic...