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Asynchronous variable hop size transmission with stochastic data model for sensor networks

- Azad, Arman, Kamruzzaman, Joarder

  • Authors: Azad, Arman , Kamruzzaman, Joarder
  • Date: 2008
  • Type: Text , Conference proceedings
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  • Description: Most existing data models and transmission policies for sensor network assume uniform periodic data generation and unconstrained transmission range for sensor nodes, both assumptions being too restrictive to capture and analyze real- world operation for practical deployment. In this paper, we consider these two practical aspects and present a new transmission policy formulated after (i) stochastic data model where a set of events occur with certain probabilities and rate of data generation by a sensor varies based on sensed event and (ii) limited transmission range of sensors. Assuming co-centric rings around the base station, located at a generic location (internal or external to the network area), ring thickness and hope sizes over lifetime is determined by formatting an optimization problem where nodes in each ring may transmit data at different hop sizes at a given instant and also vary hop sizes over lifetime. Performance analysis shows significant improvement in network lifetime and better uniformity in energy usage distribution in the proposed policy irrespective of network size and maximum allowable transmission range of nodes.

An adaptive self-configuration scheme for severity invariant machine fault diagnosis

- Yaqub, Muhammad, Gondal, Iqbal, Kamruzzaman, Joarder

  • Authors: Yaqub, Muhammad , Gondal, Iqbal , Kamruzzaman, Joarder
  • Date: 2013
  • Type: Text , Journal article
  • Relation: IEEE Transactions on Reliability Vol. 62, no. 1 (2013), p. 116-126
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  • Description: Vibration signals, used for abnormality detection in machine health monitoring (MHM), exhibit significant variation with varying fault severity. This signal variation causes overlap among the features characterizing different types of faults, which results in severe performance degradation of the fault diagnostic model. In this paper, a wavelet based adaptive training set and feature selection (WATF) self-configuration scheme is presented, which selects the optimum wavelet decomposition level, and employs adaptive selection of the training set and features. Optimal wavelet decomposition level selection is such that the maximum fault signature-signal energy bands are achieved. The severity variant features, which could cause detrimental class overlap for MHM, are avoided using adaptive selection of the training set and features based on the location of a test data in feature space. WATF uses Support Vector Machines (SVM) to build the fault diagnostic model, and its performance and robustness has been tested with data having different severity levels. Comparative studies of WATF with eight existing fault diagnosis schemes show that, for publicly available data sets, WATF achieves higher fault detection accuracy, even when training and testing data sets belong to different severity levels.

Agile spectrum evacuation in cognitive radio networks

- Shahid, Mohammad, Kamruzzaman, Joarder

  • Authors: Shahid, Mohammad , Kamruzzaman, Joarder
  • Date: 2010
  • Type: Text , Conference paper
  • Relation: 2010 IEEE International Conference on Communications p. 1-6
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  • Description: One of the most important aspects of cognitive radio technology is to avoid interference on the primary system. Typically, the interference is avoided by sensing a particular spectrum band for the existence of primary transmitter while all secondary users are kept quiet. Hence, a periodic sensing method is used which incorporates alternate phases of sensing and transmission by all secondary users. In this paper, we introduce a new method of agile spectrum evacuation that allows any secondary user to continue using the band until the return of the primary user is detected through the formation of a set of users that exclusively engages in sensing primary user in a cooperative manner. The proposed method yields better interference protection and enhanced spectrum utilization.

VoIP call capacity over wireless mesh networks

- Siddique, Md, Kamruzzaman, Joarder

  • Authors: Siddique, Md , Kamruzzaman, Joarder
  • Date: 2008
  • Type: Text , Conference paper
  • Relation: 2008 IEEE Global Telecommunications Conference p. 1-6
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  • Description: In recent years, research on VoIP over wireless mesh network (WMN) has gained particular attention because of its commercial prospect. This paper presents an analytical method to estimate VoIP call capacity in an WMN employing IEEE 802.11 devices. We used Markov chain analysis of IEEE 802.11 for network delay and loss to estimate the capacity while using rating factor, R score, defined by ITU-T, to ensure call quality. A detailed analysis of queueing delay and loss in terms of network parameters is also carried out along with their impacts on voice quality. The capacity model estimates call capacity in a single hop WLAN and is extendable to multi hop scenario and for video communications. The theoretical results are verified by simulation and compared to related previous works.

An adaptive approach to opportunistic data forwarding in underwater acoustic sensor networks

- Nowsheen, Nusrat, Karmakar, Gour, Kamruzzaman, Joarder

  • Authors: Nowsheen, Nusrat , Karmakar, Gour , Kamruzzaman, Joarder
  • Date: 2014
  • Type: Text , Conference proceedings
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  • Description: Reliable data transfer for underwater acoustic sensor networks (UASNs) is a major research challenge in applications such as pollution monitoring, oceanic data collection, and surveillance due to the long propagation delay and high error rate of the acoustic channel. To address this issue, an opportunistic data forwarding protocol was proposed which achieves high packet delivery success ratio with less routing overhead and energy consumption by selecting the next hop forwarder among a set of candidates based on its link reliability and data transfer reach ability. However, the protocol relies on fixed data hold time approach, i.e., Each node holds data packets for a fixed amount of time before a forwarder discovery process is initiated. Depending on the value of the fixed hold time and deployment contextual scenario, this may incur large end-to-end delay. Moreover, lack of consideration of network condition in hold time limits its performance. In this paper, we propose an adaptive technique to improve its performance. The adaptive approach calculates data hold time at each node dynamically considering a number of 'node and network' metrics including current buffer occupancy, delay experienced by stored data packets, arrival and service rate, neighbors' data transmissions and reach ability. Simulation results show that compared with fixed hold time approach, our adaptive technique reduces end-to-end delay significantly, achieves considerably higher data delivery and less energy consumption per successful packet delivery.

Hidden Markov models Incorporating fuzzy measures and integrals for protein sequence identification and alignment

- Bidargaddi, Niranjan, Chetty, Madhu, Kamruzzaman, Joarder

Cooperative spectrum sensing in realistic RF environment

- Shahid, Mohammad, Kamruzzaman, Joarder

  • Authors: Shahid, Mohammad , Kamruzzaman, Joarder
  • Date: 2009
  • Type: Text , Conference paper
  • Relation: 20th Personal Indoor & Mobile Radio Communications Symposium 2009 (PIMRC2009) p. 2290-2294
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  • Description: Fixed spectrum licensing policies are unsuitable to meet RF spectrum demand by emerging technologies. Spectrum scarcity is hindering the enhancement of current services or deployment of new services operating in RF spectrum. On the contrary, many portions of the licensed spectrum remain unused or underused for significant period of time creating possibility of opportunistic spectrum access without license. Spectrum sensing is practiced in most of the existing opportunistic spectrum access methods. However, these methods consider identical fading or shadowing channels and ignore spatial variation of unlicensed users, hence fail to capture realistic scenario. We introduce an improved cooperative spectrum sensing technique which incorporates non-identical fading and shadowing, and weighs each non-licensee user's contribution appropriately considering the received power and positional displacements of the users. The proposed method demonstrates better detection accuracy and higher spectrum utilization with fewer cooperating users than other existing methods.

Application of artificial intelligence to improve quality of service in computer networks

- Ahmad, Iftekhar, Kamruzzaman, Joarder, Habibi, Daryoush

  • Authors: Ahmad, Iftekhar , Kamruzzaman, Joarder , Habibi, Daryoush
  • Date: 2012
  • Type: Text , Journal article
  • Relation: Neural Computing & Applications Vol. 21, no. 1 (2012), p. 81-90
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  • Description: Resource sharing between book-ahead (BA) and instantaneous request (IR) reservation often results in high preemption rates for ongoing IR calls in computer networks. High IR call preemption rates cause interruptions to service continuity, which is considered detrimental in a QoS-enabled network. A number of call admission control models have been proposed in the literature to reduce preemption rates for ongoing IR calls. Many of these models use a tuning parameter to achieve certain level of preemption rate. This paper presents an artificial neural network (ANN) model to dynamically control the preemption rate of ongoing calls in a QoS-enabled network. The model maps network traffic parameters and desired operating preemption rate by network operator providing the best for the network under consideration into appropriate tuning parameter. Once trained, this model can be used to automatically estimate the tuning parameter value necessary to achieve the desired operating preemption rates. Simulation results show that the preemption rate attained by the model closely matches with the target rate.

VoIP capacity over PCF with imperfect channel

- Siddique, Md, Kamruzzaman, Joarder

  • Authors: Siddique, Md , Kamruzzaman, Joarder
  • Date: 2009
  • Type: Text , Conference paper
  • Relation: IEEE Global Communications Conference (IEEE GLOBECOM2009) p. 1-6
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  • Description: Voice, in the form of VoIP, has emerged as a dominating traffic category in the Internet. VoIP traffic suffers from severe voice quality degradation if the end-to-end delay and loss becomes high. PCF medium access mechanism offers delay bound delivery which is a crucial attribute for delay sensitive applications like VoIP. But due to its unavailability in most commercial products, little analysis has been done on PCF for supporting VoIP traffic. Most importantly, standard voice quality assessment methods are not used in the capacity studies. We propose a VoIP capacity model for PCF that uses voice quality as the limiting factor and takes imperfect channel condition into account. The effects of aggregation level, packet error rate and voice quality on VoIP capacity are investigated, and a comparison between voice capacities under PCF and DCF is presented. The proposed model will be extremely useful in designing networks to support quality voice calls.

Performance analysis of PCF based WLANs with imperfect channel and failure retries

- Siddique, Md, Kamruzzaman, Joarder

  • Authors: Siddique, Md , Kamruzzaman, Joarder
  • Date: 2010
  • Type: Text , Conference paper
  • Relation: 2010 IEEE Global Telecommunications Conference p. 1-6
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  • Description: Wi-Fi enabled hand-held devices quickly occupied the consumer market as a result of the remarkable customer acceptance of IEEE 802.11 standard. But the widely used contention based medium access mechanism is unable to meet the increasing traffic demand of today's home users. Especially, delay sensitive multimedia contents suffer heavily from quality degradation under high traffic load. However, the time synchronized medium access mechanism of 802.11 called PCF offers lower delay and loss, and holds true potential in supporting high traffic load. For design and planning of such networks, a thorough performance analysis of PCF based 802.11 WLANs is of profound importance. But existing studies on this lack proper and accurate mathematical modeling considering realistic assumptions, which is investigated in this paper. We develop a Markov chain to analyze the time synchronized PCF based medium access mechanism considering error prone channels, and determine throughput, delay, and packet loss in a WLAN. The impact of traffic load and retry limit is also analyzed. We use our model to analyze performance of PCF mechanism in supporting both data and multimedia traffic.

Regularly frequent patterns mining from sensor data stream

- Rashid, Md. Mamunur, Gondal, Iqbal, Kamruzzaman, Joarder

  • Authors: Rashid, Md. Mamunur , Gondal, Iqbal , Kamruzzaman, Joarder
  • Date: 2013
  • Type: Text , Conference paper
  • Relation: International Conference on Neural Information Processing (ICONIP 2013) p. 417-424
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  • Description: Mining interesting and useful knowledge from the huge amount of data gathered in wireless sensor networks is a challenging task. Works reported in literature use support metric-based sensor association rule which employs the occurrence frequency of patterns as criteria. Such criteria may not be appropriate for finding significant patterns. Moreover, temporal regularity in occurrence behavior should be considered as another important measure for assessing the importance of patterns in WSNs. Frequent sensor patterns that occur after regular intervals is called regularly frequent sensor patterns. Even though mining regularly frequent sensor patterns from sensor data stream is extremely important in many real-time applications, no such algorithm has been proposed yet. In this paper, we propose a novel tree structure called Regularly Frequent Sensor Pattern-tree (RSP-tree) and an efficient mining approach for finding regularly frequent sensor patterns from WSNs. Extensive performance analyses show that our technique is time and memory efficient in finding regularly frequent sensor patterns.

Increasing voice capacity over IEEE 802.11 WLAN using virtual access points

- Siddique, Md, Kamruzzaman, Joarder

  • Authors: Siddique, Md , Kamruzzaman, Joarder
  • Date: 2010
  • Type: Text , Conference paper
  • Relation: Global Telecommunications Conference (GLOBECOM 2010), 2010 IEEE p. 1-6
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  • Description: Voice capacity over IEEE 802.11 networks can be increased with time synchronized medium access, but it is restricted to single hop networks only. We propose a collaborative mechanism that enables client nodes to carry out the time synchronization on ad hoc basis, thereby extends the time synchronized access mechanism over multiple hops, and increases voice capacity considerably. To model real scenario closely, we consider the impact of channel error and employ a Markov chain to determine delay and loss in both medium access and in queue which is then used to derive user perceived voice quality using ITU-T E-model. Our model is then used to determine voice capacity of multichannel, multihop networks. The impact of data rate, interference range, and multiple channels are also analyzed

Geographic constraint mobility model for ad hoc network

- Ahmed, Sabbir, Karmakar, Gour, Kamruzzaman, Joarder

  • Authors: Ahmed, Sabbir , Karmakar, Gour , Kamruzzaman, Joarder
  • Date: 2008
  • Type: Text , Conference paper
  • Relation: Proceedings of the 2008 IEEE International Symposium on Modeling, Analysis & Simulation of Computer & Telecommunication Systems
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  • Description: In this paper, we propose a mobility model and present its simulation tool to generate realistic mobility traces for mobile ad hoc network. The mobility model is capable of creating realistic node movement pattern in the presence of geographic constraints by exploiting the concepts of anchors. The model dynamically places anchors depending upon the context of the environment through which nodes are guided to move towards the destination, and obstacles of arbitrary shapes with or without doorways and any existing pathways, in full or part of the terrain can be incorporated which makes the simulation environment more realistic. The characteristics of the proposed mobility model tested on a real world university campus map at various movement patterns are presented that illustrate the impact of the mobility model on the performance of a routing protocol and usefulness of the proposed scenario generation tool.

Dynamic dwell timer for hybrid vertical handover in 4G coupled networks

- Haider, Ammar, Gondal, Iqbal, Kamruzzaman, Joarder

QoS support in event detection in WSN through optimal k-coverage

- Alam, Kh Mahmudul, Kamruzzaman, Joarder, Karmakar, Gour, Murhsed, Manzur, Azad, Arman

  • Authors: Alam, Kh Mahmudul , Kamruzzaman, Joarder , Karmakar, Gour , Murhsed, Manzur , Azad, Arman
  • Date: 2011
  • Type: Text , Conference paper
  • Relation: 11th International Conference on Computational Science, ICCS 2011; Singapore, Singapore; 1st-3rd June 2011; published in Procedia Computer Science Vol. 4, p. 499-507
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  • Description: Wireless sensor networks promise to guarantee accurate, fault tolerant and timely detection of events in large scale sensor fields. To achieve this the notion of k-coverage is widely employed in WSNs where significant redundancy is introduced in deployment as an event is expected to be sensed by at least k sensors in the neighborhood. As sensor density increases significantly with k, it is imperative to find the optimal k for the underlying event detection system. In this work, we consider the detection probability, fault tolerance and latency as the Quality of Service (QoS) metrics of an event detection system employing k-coverage and present a probabilistic model to guarantee given QoS support with the minimum degree of coverage taking into account the noise related measurement error, communication interference and sensor fault probability. This work eventually resolves the problem of over or under deployment of sensors, increases scalability and provides a well defined mechanism to tune the degree of coverage according to performance needs.

Hybrid in-network query processing framework for wireless sensor networks

- Pervin, Shaila, Kamruzzaman, Joarder, Karmakar, Gour, Azad, Arman

  • Authors: Pervin, Shaila , Kamruzzaman, Joarder , Karmakar, Gour , Azad, Arman
  • Date: 2011
  • Type: Text , Conference paper
  • Relation: 2011 IEEE International Conference on Communications, ICC 2011; Kyoto, Japan; 5th-9th June 2011 p. 1-6
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  • Description: Existing in-network query processing techniques are categorized as approximation and aggregation based approaches, where the former achieves lower network traffic at the expense of query response accuracy, whereas the later reduces query response inaccuracy by executing queries at the actual sensor nodes which necessitates the overhead of query specific sensor selection mechanism. In this paper, we propose a hybrid query processing framework that combines the advantages of both the approximation and aggregation based techniques and avoids their limitations. In our approach, we construct a hierarchical probabilistic data model representing the overall sensor data characteristics across the network, which is query independent and is later used for selecting sensor nodes to process user queries. Experimental results illustrate the efficacy of the proposed framework compared to contemporary approximation and aggregation based query processing techniques.

Detecting intrusion in the traffic signals of an intelligent traffic system

- Chowdhury, Abdullahi, Karmakar, Gour, Kamruzzaman, Joarder, Saha, Tapash

  • Authors: Chowdhury, Abdullahi , Karmakar, Gour , Kamruzzaman, Joarder , Saha, Tapash
  • Date: 2018
  • Type: Text , Conference proceedings
  • Relation: 20th International Conference on Information and Communications Security, ICICS 2018; Lille, France; 29th-31st October 2018; published in Lecure Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) Vol. 11149 LNCS, p. 696-707
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  • Description: Traffic systems and signals are used to improve traffic flow, reduce congestion, increase travel time consistency and ensure safety of road users. Malicious interruption or manipulation of traffic signals may cause disastrous instants including huge delays, financial loss and loss of lives. Intrusion into traffic signals by hackers can create such interruption whose consequences will only increase with the introduction of driverless vehicles. Recently, many traffic signals across the world are reported to have intruded, highlighting the importance of accurate detection. To reduce the impact of an intrusion, in this paper, we introduce an intrusion detection technique using the flow rate and phase time of a traffic signal as evidential information to detect the presence of an intrusion. The information received from flow rate and phase time are fused with the Dempster Shaffer (DS) theory. Historical data are used to create the probability mass functions for both flow rate and phase time. We also developed a simulation model using a traffic simulator, namely SUMO for many types of real traffic situations including intrusion. The performance of the proposed Intrusion Detection System (IDS) is appraised with normal traffic condition and induced intrusions. Simulated results show our proposed system can successfully detect intruded traffic signals from normal signals with significantly high accuracy (above 91%).
  • Description: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

A contender-aware backoff algorithm for CSMA based MAC protocol for wireless sensor network

- Miraz Al-Mamun, Miraz, Karmakar, Gour, Kamruzzaman, Joarder

  • Authors: Miraz Al-Mamun, Miraz , Karmakar, Gour , Kamruzzaman, Joarder
  • Date: 2010
  • Type: Text , Conference proceedings
  • Full Text: false
  • Description: Existing contention based nonpersistent medium access control protocols in Wireless Sensor Network (WSN) do not perform well in high contention. Their performances are affected by occurrence of collision due to uniform probability distribution in choosing Time Slot (TS) during backoff period. To address this issue nonuniform probability distribution was proposed. However success rate still drops for higher number of contenders. In this paper we propose CSMA/s (Collision Sense Multiple Access /per Slot based), a new approach in nonuniform contender-aware probability distribution for choosing TS in the backoff period. Rather than taking a premeditated fixed value for contender population size, our proposed scheme embeds neighborhood population size into its bedrock to automatically converge to the actual number of contenders which enables the contender to adaptively choose TS in the backoff period for reducing collision. This method produces better success rate and lower latency for even very high number of contenders.

QoS-centric collision window shaping for CSMA-CA MAC protocol

- Miraz Al-Mamun, Miraz, Karmakar, Gour, Kamruzzaman, Joarder

  • Authors: Miraz Al-Mamun, Miraz , Karmakar, Gour , Kamruzzaman, Joarder
  • Date: 2010
  • Type: Text , Conference proceedings
  • Full Text: false
  • Description: Collision Sense Multiple Access (CSMA) has been preferred to Time Division Multiple Access (TDMA) as medium access scheme for Wireless Multimedia Sensor Network (WMSN) in the scenarios where the traffic is bursty in nature and multiple consecutive and contiguous packets generated from the same collision neighborhood need to be sent. Protocols based on nonuniform probability distribution do not perform well in high contention and heterogeneous traffic scenarios due to nonadaptive nature to contention neighborhood. In this paper we have proposed a scheme to adapt the Contention Window (CW) size according to the collision neighborhood population complying with the application specific latency and success probability constraints. This scheme shows improved performance compared with SIFT, a stereotype of non-uniform probability based CSMA protocol and can be deployed with any CSMA-CA (CSMA with Collision Avoidance) based backoff algorithm

Coexistence mechanism for industrial automation network

- Yaqub, Muhammad, Gondal, Iqbal, Kamruzzaman, Joarder

  • Authors: Yaqub, Muhammad , Gondal, Iqbal , Kamruzzaman, Joarder
  • Date: 2010
  • Type: Text , Conference paper
  • Relation: 12th IEEE International Conference on High Performance Computing and Communications
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  • Description: Increase in the number of coexisting networks in license free Industrial, Scientific and Medical (ISM) band causes interferences for industrial automation, e.g., shop floors of manufacturing facilities. In order to ensure the reliability for automation networks, interference avoidance schemes are required. This paper proposes a novel Predefined Hopping Pattern (PHP) technique for frequency hopping in ISM band, which mitigates self-interferences and static interferers as well. This technique generates optimized frequency hopping sequences which ensure sufficient frequency diversity and frequency offset among the coexisting Bluetooth piconets and exploits transmission experiences for a particular frequency in eliminating interference. Simulation studies have shown that PHP has better collision avoidance rate than well known adaptive frequency hopping (AFH) and adaptive frequency rolling (AFR) schemes.