KMITL

Permanent URI for this communityhttps://dspace.kmitl.ac.th/handle/123456789/1

Browse

Search Results

Now showing 1 - 9 of 9

Some of the metrics are blocked by your
consent settings
A Novel Precomputed Optimal Procrastination Time Interval for Re-Clustering to Maximize Operation Time of Wireless Sensor Networks
(2023-09-01)
Pornavalai, Chotipat
;
Tanessakulwattana, Sarayoot
;
Chakraborty, Goutam
In wireless sensor networks, the energy consumption of sensors is not uniform over the whole region of deployment. The uneven energy usage occurs because some sensors have to transmit data to farther distances or have to transmit more data packets than others. This leads to a shorter duration of operation because some sensors' energy will deplete fast creating holes in the network. To alleviate this problem, we proposed an algorithm we named Procrastinated Clustering and Multi-Hop Routing (PCMR). To prolong the operation, it will optimally assign sensors with different precomputed procrastination periods to schedule the clustering and routing processes. In PCMR, sensors' clustering and routing intervals depend on their locations in the network with respect to the sink. The algorithm could reduce and balance energy consumption for sensors distributed over a wide area. Procrastination periods are precomputed off-line before deployment. Therefore, it is easy to implement and is efficient, even for a large network for which real-time reorganization would involve transmitting a large number of signaling packets. The results from simulations show that the proposed PCMR algorithm could balance energy usage among sensors, and prolong the network lifetime compared to existing works based on techniques such as adjusting cluster size and/or multi-path transmission.
Some of the metrics are blocked by your
consent settings
Optimal Distribution of Traffic in Manhattan Road Networks for Minimizing Routing-Time
(2021-11-01)
Sarma, Sayan Sen
;
Sinha, Koushik
;
Sub-R-Pa, Chayanon
;
Chakraborty, Goutam
;
Sinha, Bhabani P.
In a natural disaster, when there is a sudden rush in vehicle movement from dense residential areas of a city towards some designated evacuation centers, traffic needs to be distributed along the road network in an optimal way so as to minimize the travel time for reaching those evacuation centers. We address this traffic distribution problem in a k \times k Manhattan road network with multiple traffic generating sources and a single fixed destination (sink) at a corner point. We first consider queuing delay at each grid point along with a fixed link delay. We then extend our idea to consider a rectangular grid and also real-life road networks where some of the links may be absent. We present a traffic distribution algorithm that would minimize the average time of all vehicles to reach the given destination point. Simulation of our algorithm using SUMO on the grid-structured road map of Manhattan borough in New York city and also on a part of non-grid road map of city of Carbondale, IL USA shows a much shorter average travel time compared to the existing popular algorithms based on dynamic traffic assignments (DTA). The proposed technique is also robust in the sense that even with 20% deviation from optimal assignment of traffic distribution at cross-points, we get significantly better results compared to the existing traffic distribution policies. We then propose a congestion control technique based on detouring of vehicles and show how variable link delay as a function of the volume of traffic flow through a link can be incorporated in our traffic distribution policy. Finally, we show how to extend our technique to consider a scenario with the destination point being anywhere on the grid, instead of being at the corner point.
Some of the metrics are blocked by your
consent settings
Adaptive multi-hop routing for wireless sensor networks
(2013-09-09)
Tanessakulwattana, Sarayoot
;
Pornavalai, Chotipat
;
Chakraborty, Goutam
A large portion of energy-aware routing protocol for wireless sensor networks are cluster-based. In cluster based approach, energy at the cluster head nodes are drained more rapidly compared to other member nodes. Dynamically change cluster heads periodically could partialy mitigate this problem, but clusters that are far from base station still suffer from large amount of energy for directly transmit their cluster data back to base station. Multi-hop routing was introduced to reduce energy dissipation of cluster heads that far away from base station by relaying data through nearer cluster heads. However it may overload cluster heads that are near the base station. In this paper, we propose an adaptive multi-hop hierarchical routing approach where member nodes in cluster may send their data, based on distance information, to cluster head or to base station directly to reduce energy dissipation of cluster heads. This decision is independent at each node which makes this approach highly distributed. Simulation results show that the proposed routing protocol has longer node lifetime than the original LEACH and M-LEACH protocol. © 2013 IEEE.
Some of the metrics are blocked by your
consent settings
Optimal multi-path energy-aware routing protocol for wireless sensor networks
(2012-10-02)
Tanessakulwattana, Sarayoot
;
Pornavalai, Chotipat
;
Chakraborty, Goutam
;
Naik, Sagar
A large portion of energy-aware routing protocol for wireless sensor networks are cluster-based. In cluster based approaches, power of the cluster head (CH) nodes are drained more rapidly compared to other member nodes. Dynamic CH approach could partially alleviate this problem. But even with dynamic CH approach, energy is not uniformly dissipated among all nodes. In this paper, we propose a new energy-aware routing protocol where the communication protocol is such that, even when the clusters are fixed, power dissipation is same over all nodes (except CHs). Every node co-operates with each other to carry the payload to the CH so as the power dissipation is uniform. Therefore reconfiguration of cluster is not necessary, thereby saving a huge signalling cost and interruption in service. Simulation results show that the proposed protocol has longer node lifetime and better distribution of energy dissipation than the original LEACH protocol. © 2012 IEEE.
Some of the metrics are blocked by your
consent settings
An MLP-based face authentication technique robust to orientation
(2009-11-20)
Chakraborty, Goutam
;
Chakraborty, Basabi
;
Patra, Jagdish C.
;
Pornavalai, Chotipat
The need for stricter security, availability of sophisticated algorithms and improved hardware at cheaper price, are the driving forces for increasing popularity of biometric authentication. Machine authentication from face images or fingerprints at the entrance of a building or at bank-teller is getting more and more common. The popularity of using face image features for authentication is due to its ease of use. But its success depends on proper orientation and illumination. Facial features change with the angle of orientation, and even a genuine person would be rejected by the machine due to improper orientation of the face towards the camera. In this work, we proposed a multi-layer perceptron based face identification technique which is robust to orientation of the face image under similar illumination condition. Training data of facial features against orientation angle features is used to train a Multi-Layer Perceptron (MLP). It is then used for interpolation of facial features at different angles. Experiments were conducted with two types of face image identifying features, using PCA and ICA. A good interpolation property could be obtained by the trained MLP, and a zero equal error rate (EER) could be achieved. © 2009 IEEE.
Some of the metrics are blocked by your
consent settings
Fuzzy-spray: Efficient routing in delay tolerant ad-hoc network based on fuzzy decision mechanism
(2009-01-01)
Mathurapoj, Akadet
;
Pornavalai, Chotipat
;
Chakraborty, Goutam
Delay Tolerant Network (DTN) is a sparse and intermittently connected mobile wireless network where reliable communication and end-to-end connectivity cannot be assured. In DTN, a node delivers messages to the destination using store and forward scheme. Messages are copied and transferred to multiple relay-nodes in order to increase the opportunity for that message to reach the intended destination. Contact is the time duration for which two or more mobile nodes encounter each other within their radio transmission ranges, and are able to transfer messages. Due to arbitrary node movement, contact time will be varied, and is unlikely to be predictable. In this paper, we propose a fuzzy decision mechanism we called "fuzzy-spray", to improve the routing and packet transfer efficiency in DTN environment. Fuzzy-spray can reduce overall latency in DTN by intelligently selecting appropriate messages to send to the relay-node during its next contact time. It uses fuzzy logic to prioritize messages that are stored in the buffer, based only on local parameters from each message, namely forward transmission count and message size. There is no need to know a priori information about network such as node mobility model, or node-distribution across the deployed area. The simulation results show that fuzzy-spray has the best performance in terms of overall speed of delivery, and lowest average message delay compared with other existing algorithms. ©2009 IEEE.
Some of the metrics are blocked by your
consent settings
An adaptive alert message dissemination protocol for VANET to improve road safety
(2009-01-01)
Suriyapaiboonwattana, Kanitsorn
;
Pornavalai, Chotipat
;
Chakraborty, Goutam
Vehicular Ad-hoc Network (VANET) is gaining much attention recently because of its many important applications in transportation, to improve road safety, reduce traffic congestion, to enable efficient traffic management etc. However, there are several technical issues to be addressed for its effective deployment. Stability in communication in VANET is difficult to achieve due to rapid network changes. Restoration is inefficient while using traditional protocols based on broadcast storm. In this paper, we propose a new adaptive protocol to improve performance for on road safety alert application in VANET. It can alleviate the broadcast storm problem using adaptive wait-windows and adaptive probability to transmit. Simulation shows that our proposed approach has better performances in terms of number of collision, success rate, and delay, when compared with other existing protocols. ©2009 IEEE.
Some of the metrics are blocked by your
consent settings
Dynamic multicast routing in advance resource reservation environment
(2000-01-01)
Pornavalai, Chotipat
;
Chakraborty, Debasish
;
Chakraborty, Goutam
;
Shiratori, Norio
Since usually the network resource is limited, the abilities to do resource reservation in advance, as well as efficient dynamic multicasting when destination nodes can join and leave the group during the communication period, are essential in all distributed multi-party applications. Total or partial re-routing of multicast tree for dynamic multicast groups can optimize the tree cost to some extent but they are complex. Furthermore, optimal multicast routing has been proved to be an NP-complete problem. In this paper, we propose an efficient dynamic multicast routing algorithm, which optimize the total cost of the Steiner tree over the whole session period in advance resource reservation environment, where information about the resource reservation (i.e. leaving times of participants at the time of joining) are available. The efficiency of our algorithm over other existing algorithms is shown by various simulation results.
Some of the metrics are blocked by your
consent settings
Optimal routing for dynamic multipoint connection
(1999-01-01)
Chakraborty, Debasish
;
Shiratori, Norio
;
Chakraborty, Goutam
;
Pornavalai, Chotipat
Multimedia applications are becoming increasingly important as networks arc now capable to carry continuous media traffic, such as voice and video, to the end user. Most of the multimedia applications need multicast support too. In dynamic multicasting, destination nodes can join and leave the group during the communication period. Total or partial rerouting can optimize the tree cost to some extent. But rerouting for optimization is complex as cell-ordering at ATM switches has to be preserved. Optimum Steiner tree is NP-complete and therefore the present problem too. We propose a heuristic centralized routing algorithm, which optimize the total cost of the Steiner tree over the whole session period, where information about the joining and leaving of participants are available, at the time s/he actually joins. With this algorithm, the average hop-length from source to destination has also reduced considerably. The efficiency of our algorithm and comparison with other proposed algorithms is shown by various simulation results.

KMITL

Browse

Filters

Settings

Sort By

Results per page

Search Results