Papers by Hossein Ghaffarian
Research Square (Research Square), Jan 19, 2023
Software-de ned networks separate the controlling and data layers in computer networks. It will e... more Software-de ned networks separate the controlling and data layers in computer networks. It will enable central management and the ability to de ne policies and apply them to network hardware. Tra c engineering, which measures and manages network tra c, is a major activity in these networks. Data should be monitored when tra c is excessive and tra c should be manipulated. Among the most important issues to consider in a network is monitoring. In this case, the network is based on SDN. Over ows on a network do not allow switches to manipulate the network. As mentioned above, this over ow is aggregation and usually based on broadcasting principles. This article describes how links work at the network level using parameters of ow, link capacity, and the optimal allocation of pro ts. This paper attempts to reduce congestion, reduce packet losses, and optimize delay through a number of methods. This paper proposes a method (PSOCB) based on SDN. Using the meta-heuristic methods to allocate the cluster switches existing in the network between the source and destination and the method of optimizing, the throughput of particles is increased by 13% in switches, and 8% in links. There is a reduction in delay when compared to the base paper. The proposed method experienced congestion at one time higher than the base paper, and at other times lower. In case of congestion removal, the network returns to its normal state. Overall, this method improves congestion as well.
Wireless Personal Communications, Nov 22, 2020
In this paper, we propose vertical and horizontal methods to reduce size of search area in indoor... more In this paper, we propose vertical and horizontal methods to reduce size of search area in indoor localization applications. Although, larger fingerprints means better accuracy, mostly indoor localization applications are running in mobile devices with limited battery, memory, and even processing power. In the proposed approaches, we reduce the size of fingerprints using reducing Access Points (APs) information (vertical reduction) and reducing fingerprint records (horizontal reduction). In vertical reduction, we focus on the importance of APs based on their appearance in fingerprint records. In horizontal reduction, we use regression and decision tree classifiers for primary location estimation. Then, only records in a predefined neighbourhood radius are selected for final localizations. Our studies show that the results of the vertical reduction approaches have a better performance against the results of the horizontal reduction approaches during the indoor localization phase. Also, these findings show that the best way to reduce the size of the fingerprints file is by removing the most common APs from the list.
In the new millennium, world has experienced a fast development in information and communications... more In the new millennium, world has experienced a fast development in information and communications technology (ICT) and divide gap has grown between poor and rich, developed and undeveloped countries. In this situation, lack of attention to outland and rural zones, makes variant prejudices between people, and finally, it causes wide variety of unorganized problems in the countries and serious problems for governments. An efficient low cost developing is the key note in ICT development. While lack of communication infrastructures in rural and outland zones, will increase costs. Because of worldwide approval of wireless networks, using Wireless Metropolitan Area Networks can address an efficient low cost way for developing ICT infrastructures. In this paper, we will consider role of these networks in development of ICT infrastructures and challenges facing them. Also, we will compare them with other existing communication technologies with respect to performance and security parameters in order to establish which technology meet to wideband, high speed and low cost connections requirements.
Wireless Personal Communications, Jun 21, 2017
The optimum deployment of sensors to provide the highest rate of environmental coverage in wirele... more The optimum deployment of sensors to provide the highest rate of environmental coverage in wireless sensor networks is one of the most important challenges in these types of networks. Apart from the analysis of data, the impact of an intrusion detection system on the performance of system is in a direct relation with the amount of collected data by sensors. Thus, proper deployment of the data collection sensors in intrusion detection systems is quite an important issue. In this article, we consider the subject of optimizing the coverage for wireless sensor networks without infrastructures by using wireless intrusion detection sensors. Due to the efficiency of wireless networks without infrastructures in inner and outer environments, both of these environments are considered in the simulations. Moreover, some of effective parameters in installation the sensors, such as existence of connecting chains between the sensors for transferring collected data, preferred areas for coverage, along with negative effects in distribution of wireless waves like environmental obstacles, the signal strength after weakening and the minimum receiving potentials in the original receiver are considered in simulations. In such situations, a real-world environment and actual conditions are provided in covering and deployment of the sensors. Simulations are done by MATLAB and the covering rates are given both numerically and graphically as the outcomes of each experiment. The
Road traffic management: traffic controllers, mobility and VANET
Institution of Engineering and Technology eBooks, Jul 24, 2013
With a long history, traffic controllers have great impact in our lives. In this chapter, we revi... more With a long history, traffic controllers have great impact in our lives. In this chapter, we review five critical components in controlling traffic. We show that how different elements of these components can affect the traffic systems. Also, we present a quick review on mobility models, from communication engineers' and traffic engineers' perspectives. We show how these views are different from each other's. Intelligent transportation system (ITS) and its presence in the traffic controllers are the next topic of this chapter. Architecture of macroscopic and microscopic traffic controllers is explained too. Finally, we review the current issues in collaboration between VANET and traffic controllers before the conclusion of the chapter. The reviewed issues are deploying VANET infrastructures and using VANET-based P2P networks in traffic information systems.
A New Fast Framework for Anonymizing IoT Stream Data
The Internet of Things (IoT) plays an important role in human life today. Millions of devices gen... more The Internet of Things (IoT) plays an important role in human life today. Millions of devices generate and transmit vast amounts of data. Exploring this data without compromising privacy practices may expose to risk of users’ identities. One of the measures used to protect data privacy is anonymity methods. IoT data anonymization is not possible using traditional methods because such data, unlike database data, are not static and are very large. In this paper, we propose a new framework that can anonymize the received stream data by considering their expiration time. This anonymization is performed using a new clustering method using a streaming data processing engine. The introduced clustering method has a significant effect on reducing data delay. It supports both numerical and categorical data types too. Also, merging remaining clusters at the end of the method has minimized information loss. Comparing the performance results of the introduced method with similar methods shows that the proposed method performs better in terms of information loss and data delay.
Input value prediction of parameters in laser bending using Fuzzy and PSO
Soft Computing, Jan 30, 2017
This paper presents a novel Fuzzy-based bending angle predictor in laser bending process. Upon th... more This paper presents a novel Fuzzy-based bending angle predictor in laser bending process. Upon the case, and situations, different input data, membership functions and rules are developed dynamically for the Fuzzy predictor. Our main focus in developing the proposed controller is keeping generality of design. So, the controller can be adapted in different cases easily. To compensate for the possible lack of knowledge of experts for developing rule base of a Fuzzy controller, here, nonlinear regression is used as an alternative approach for developing the rule base. Furthermore, the performance of the controller is improved using particle swarm optimization (PSO) method. Also, based on the proposed Fuzzy controller and PSO, another predictor able to find one possible set of input values to catch a predefined angle is proposed. Several experimental tests were conducted to evaluate performance of the proposed controllers. Comparing experimental and predicted results shows that they are in a proper agreement with our claim.
Advances in Micro Electro Mechanical Systems (MEMS)
— In this paper a new fuzzy based approach for improving network coverage in wireless mobile sens... more — In this paper a new fuzzy based approach for improving network coverage in wireless mobile sensor networks is proposed. In the proposed approach firstly each mobile sensor node determines its neighbors and its distance from borders and obstacles. According to these values, fuzzy inference engine calculates the priority of node for movement. Then according to the priority, in turn, nodes move away from each other to increase coverage area in the target field. Simulation results show that our fuzzy approach can reach higher degree of coverage against other common approaches like FOA, VEC and TRI algorithms.
Apache Flink and clustering-based framework for fast anonymization of IoT stream data
Intelligent Systems with Applications
A Framework for Distributed Feature Selection
International Journal of Pattern Recognition and Artificial Intelligence
Many current multivariate filter feature selection approaches consider redundancy and relevance b... more Many current multivariate filter feature selection approaches consider redundancy and relevance between features and class vectors simultaneously. However, these multivariate filter algorithms calculate the suitability of features by only the intrinsic characteristics of the data. In this paper, we suggest a new distributed framework to offset the multivariate feature selection problem. We propose the interaction with classifiers in multivariate filter feature selection. Our proposed framework calculates the relevance of each feature to class labels by embedded algorithms. Then, this technique examines redundancy among features through multivariate filter algorithms. In addition, in the proposed framework, we use horizontal distribution of data instead of using all them once. This approach reduces the runtime of the process in datasets with many samples and environments without centralized data. The results of the evaluation show that the proposed framework can improve classificatio...
Research Square (Research Square), Jan 19, 2023
Software-de ned networks separate the controlling and data layers in computer networks. It will e... more Software-de ned networks separate the controlling and data layers in computer networks. It will enable central management and the ability to de ne policies and apply them to network hardware. Tra c engineering, which measures and manages network tra c, is a major activity in these networks. Data should be monitored when tra c is excessive and tra c should be manipulated. Among the most important issues to consider in a network is monitoring. In this case, the network is based on SDN. Over ows on a network do not allow switches to manipulate the network. As mentioned above, this over ow is aggregation and usually based on broadcasting principles. This article describes how links work at the network level using parameters of ow, link capacity, and the optimal allocation of pro ts. This paper attempts to reduce congestion, reduce packet losses, and optimize delay through a number of methods. This paper proposes a method (PSOCB) based on SDN. Using the meta-heuristic methods to allocate the cluster switches existing in the network between the source and destination and the method of optimizing, the throughput of particles is increased by 13% in switches, and 8% in links. There is a reduction in delay when compared to the base paper. The proposed method experienced congestion at one time higher than the base paper, and at other times lower. In case of congestion removal, the network returns to its normal state. Overall, this method improves congestion as well.
Proposing a New Fast and Robust Framework for Anonymizing IoT Data Streams Using Apache Flink
SSRN Electronic Journal
Comparison of Data Mining Algorithms' Efficiency in Thyroid Disease Diagnosis
Journal of Payavard Salamat, 2020
In this paper, we focus to find desired node position in indoor environments using a sequence of ... more In this paper, we focus to find desired node position in indoor environments using a sequence of observations and user movement records. For this purpose, we first record the user's movements in indoor environments by defining a set of states and several matrices, which are Viterbi inputs. In order to record the fingerprints of the environment, we move across the entire coordinates of the building to collect and record the fingerprints of different places. In online phase, we use the Weighted K-Nearest Neighbors (WKNN) algorithm in parallel to check the accuracy of both WKNN and Viterbi algorithms and to correct the WKNN behavior by Viterbi. During this phase, an experimental node is inserted into the environment and moves in the desired direction by determining the destination. The proposed method calculates the current location of the node and its most probable location in the next step. The results of the implementation and testing of the proposed algorithm in the Faculty of ...
— In this paper, a new MAC based approach has been proposed to improve fairness in TCP and UDP fl... more — In this paper, a new MAC based approach has been proposed to improve fairness in TCP and UDP flows in VANET. Since TCP has been developed for wired networks, in wireless networks, especially the ones based on IEEE 802.11 standard, it has fairness problems. The common proposed MAC based approaches, using a timer, have only worked on fairness improvement among TCP flows. UDP flows form major parts of network traffics. According to the lack of flow and congestion control mechanisms in UDP traffics, in our proposed approach, both types of traffic have been considered together. We add different amount of delay into packets, based on their types. The simulation results indicate fairness improvement in VANETs.
Vehicular ad hoc networks enabled traffic controller for removing traffic lights in isolated intersections based on integer linear programming
IET Intelligent Transport Systems, 2012
Traffic management, especially in intersections, is an important part of intelligent transportati... more Traffic management, especially in intersections, is an important part of intelligent transportation systems (ITS). In this study, a new traffic controller is proposed which removes traffic lights in intersections. The heart of the proposed controller is a simple integer linear program (ILP) code. This program manages safe driving patterns crossing a junction while it tries to maximise number of passed vehicles across the intersection. The demanded data are prepared by vehicular ad hoc networks (VANET). The proposed safe driving pattern assures the safety of moving vehicles and avoiding any accident. Simulation results show that the proposed controller performs efficiently. The average queue lengths and also tolerated delay by vehicles are far better than traditional approaches. Also, for different probabilities of output selection, the proposed approach remains stable yet.
Investigation of Wireless Metropolitan Area Networks Effect on Information and Communication Tech... more Investigation of Wireless Metropolitan Area Networks Effect on Information and Communication Technology Development
In this paper a new fuzzy based approach for improving network coverage in wireless mobile sensor... more In this paper a new fuzzy based approach for improving network coverage in wireless mobile sensor networks is proposed. In the proposed approach firstly each mobile sensor node determines its neighbors and its distance from borders and obstacles. According to these values, fuzzy inference engine calculates the priority of node for movement. Then according to the priority, in turn, nodes move away from each other to increase coverage area in the target field. Simulation results show that our fuzzy approach can reach higher degree of coverage against other common approaches like FOA, VEC and TRI algorithms.
A New Fast Framework for Anonymizing IoT Stream Data
2021 5th International Conference on Internet of Things and Applications (IoT), 2021
The Internet of Things (IoT) plays an important role in human life today. Millions of devices gen... more The Internet of Things (IoT) plays an important role in human life today. Millions of devices generate and transmit vast amounts of data. Exploring this data without compromising privacy practices may expose to risk of users’ identities. One of the measures used to protect data privacy is anonymity methods. IoT data anonymization is not possible using traditional methods because such data, unlike database data, are not static and are very large. In this paper, we propose a new framework that can anonymize the received stream data by considering their expiration time. This anonymization is performed using a new clustering method using a streaming data processing engine. The introduced clustering method has a significant effect on reducing data delay. It supports both numerical and categorical data types too. Also, merging remaining clusters at the end of the method has minimized information loss. Comparing the performance results of the introduced method with similar methods shows th...
Distributed Scheduling in Wireless Mesh Networks
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Papers by Hossein Ghaffarian