Effect of Relay Nodes on End-To-End Delay in Multi-Hop Wireless Ad-Hoc Networks

Channel access delay in a wireless adhoc network is the major source of delay while considering the total end to-end delay. Channel access delays experienced by different relay nodes are different in multi-hop adhoc network scenario. These delays in multi-hop network are analysed in the literature assuming channel access delays are independent and are of same magnitude at all the nodes in the network. In this work, the end to-end delay in a multi-hop adhoc network is analysed taking into account the silent relay nodes. Along with silent relay node effect, Channel access probability (p), transmission radius (r) analogous to transmit power, network throughput and density of nodes arête other factors considered for the end-to-end delay analysis. Effect of network parameters along with silent relay nodes on end-to-end delay is found to be considerably high compared to the previous literature results. Given a bound on end-to-end delay with percentage of silent relay nodes, throughput, node density requirements for a multi-hop adhoc network, optimal ranges of transmission radius and channel access probability can be obtained from the proposed analysis. End-to-end delay increases with silent relay nodes along with transmission radius(r), channel access probability(p), node density and throughput. It is clear from the analysis, that the effect of silent relay nodes on end to-end delay cannot be ignored to maintain certain Quality of service (QoS) metrics for the multi-hop wireless adhoc networ

FLAVONOID CONTENT AND ANTIBACTERIAL ACTIVITY OF ALBIZIA JULIBRISSIN. DURAZZ LEAF, STEM AND FLOWER EXTRACTS AGAINST CLINICALLY ISOLATED BACTERIAL PATHOGENS

Objective: To test the antibacterial efficacy of leaf, stem, and flower extracts of Albizia julibrissin against bacterial pathogens. Methods: Extraction of active metabolites was carried out by using six different solvents, and total flavonoid content in each extract was determined by Aluminium chloride method. To determine the antibacterial activity of extracts, disc diffusion method and tube dilution method were carried out. Zone of inhibition and Minimum inhibitory Concentration (MIC) were calculated. Results: Methanolic extracts of leaf samples of A. julibrissin showed highest extractive value (5.14g/100g) and total flavonoid content (35.14mg/g). In overall leaf extracts of A. julibrissin showed maximum zone of inhibition towards P. vulgaris (10.1 mm*) and least susceptible microorganism is S. typhi (3.5 mm*). Stem and flower extracts inhibited bacterial growth only at higher concentrations (MIC, 160-215 and 65-180µg/ml respectively). Conclusion: Apart from the energy crop, based on the results and value-added compounds present in A. julibrissin, it may be considered as antibacterial agent in future

Effect of relay nodes and transmit power on end-to-end delay in multi-hop wireless ad hoc networks

Channel access delay in a wireless multi-hop ad hoc network is the major source of delay while considering end-to-end delay. In this work, end-to-end delay is analysed considering silent relay nodes and effect of network parameters like node density and throughput. Given network parameter requirements and bound on end-to-end delay, optimal ranges of transmission radius and channel access probability can be obtained from the proposed analysis. Effect of silent relay nodes must be considered to maintain quality of service (QoS) metrics. Transmission power adaptability to reduce end-to-end delay is analysed considering the interference model. Increase in transmission power is not reducing end-to-end delay linearly. Simulation results show that increase in end-to-end delay due to channel access probability and throughput is onsiderably higher than node density. Also given the network parameters, end-to-end delay can be minimised only up to certain value irrespective of increase in transmit power

Neural Network based Short Term Forecasting Engine To Optimize Energy And Big Data Storage Resources Of Wireless Sensor Networks

Energy efficient wireless networks is the primary research goal for evolving billion device applications like IoT, smart grids and CPS. Monitoring of multiple physical events using sensors and data collection at central gateways is the general architecture followed by most commercial, residential and test bed implementations. Most of the events monitored at regular intervals are largely redundant/minor variations leading to large wastage of data storage resources in Big data servers and communication energy at relay and sensor nodes. In this paper a novel architecture of Neural Network (NN) based day ahead steady state forecasting engine is implemented at the gateway using historical database. Gateway generates an optimal transmit schedules based on NN outputs thereby reducing the redundant sensor data when there is minor variations in the respective predicted sensor estimates. It is observed that NN based load forecasting for power monitoring system predicts load with less than 3% Mean Absolute Percentage Error (MAPE). Gateway forward transmit schedules to all power sensing nodes day ahead to reduce sensor and relay nodes communication energy. Matlab based simulation for evaluating the benefits of proposed model for extending the wireless network life time is developed and confirmed with an emulation scenario of our testbed. Network life time is improved by 43% from the observed results using proposed model

Analytical Model of Adaptive CSMA-CA MAC for Reliable and Timely Clustered Wireless Multi-Hop Communication

Reliability and delay of a single cluster wireless network is well analysed in the literature. Multi-hop communication over the number of clusters is essential to scale the network. Analytical model for reliability and end-to-end delay optimization for multi-hop clustered network is presented in this paper. Proposed model is a three dimensional markov chain. Three dimensions of markov model are the adaptable mac parameters of CSMA-CA. Model assumes wakeup rates for each cluster. Results show that reliability and delay are significantly improved than previous analytical models proposed. It has been observed that overall reliability of multi-hop link is improved, with reduction in end-to-end delay is reduced even at lower wakeup rates of a cluste

FPGA based implementation of low complex adaptive speckle suppression filter for B-mode medical ultrasound images

Speckles are considered as noise, which masks the fine information present in B-mode ultrasound images. Speckles appears as small snakes and dense granular like structures which has serious impact on visual perception of an image. Adaptive filter based on local statistics of an image is used to enhance the image by suppressing the noise. Adaptive speckle suppression filter enhance the image by reducing the variance between intrapixel intensities in homogeneous regions and preserving variance across interpixel intensities across the nonhomogeneous regions. In this paper, we implemented low complex adaptive speckle suppression filter on FPGA based kintex7 board. The performance of the filter is evaluated by plotting the pixel variations of original image with filtered image of an ultrasound phantom. The results show that proposed algorithm can be implemented on mobile ultrasound platforms due to 50% less computations needed per pixel compared to traditional adaptive speckle suppression algorithms, which aids better diagnosis for healthcare

PHARMACOGNOSTIC EVALUATION OF ABIES WEBBIANA LEAF: A SIDDHA HERBAL INGREDIENT

ABSTRACTObjectives: To evaluate the therapeutic potential of Abies webbiana (Wall ex D. Don) Lindl, plants leaves belongs to Pinaceae family are grown inNorthern India, Afghanistan, China (Tibet), Nepal, and Pakistan. It is a large tree grows up to 50 m height. Leaves of this plant are useful in Siddha andAyurveda Systems of Medicine. It acts as an expectorant, carminative, stomachic, and tonic. It is the main ingredient in the Siddha formulations suchas Thalisathi choornam and Thalisadi vadagam, which are used for respiratory problems such as cold, cough, wheezing, tuberculosis, indigestion, lossof appetite, and vatha diseases.Methods: In this study, we have investigated the phytochemical profile, pharmacognostic characters, and gas chromatography-mass spectrometry(GC-MS) compounds of methanolic extract of A. webbiana leaves.Results: Phytochemical screening showed the presence of steroids, terpenes, sugars, phenols, flavonoids, tannins, saponins, and quinones. The leafmaterial revealed loss on drying (6.90%), total ash (5.23%), acid-insoluble ash (0.57%), water-soluble extractive (23.79%), alcohol-soluble extractive(18.37%), and pH was 5.25. 29 compounds were detected in GC-MS analysis and benzenepropanol, 4-hydroxy-à-methyl, 2-furancarboxaldehyde, and5-(hydroxymethyl) are the predominant components.Conclusions: This study provides the pharmacognostic standards of A. webbiana leaf for their authentication and utilization in herbal medicine.Keywords: Abies webbiana, Pharmacognosy, Phytochemicals, Gas chromatography-mass spectrometry, Herbal medicine

Real time Power Capping with Smart Circuit Breaker to maximize Power Utilization of Local Generator

Effective energy management and control is an important and urgent issue in the emerging and developing countries, so as to achieve their sustainable growth, because of poor quality of power supply by their electric power companies. In order to come up with the frequent electric power outage by the power company, most of buildings in developing and emerging countries install a power generator. Although because of poor control system in the premises, utilization factor of output capability of power generators is typically low except at peak periods. To improve the utilization factor of power generator, we propose a system, which can manage power segments in the building using SCB (Smart Circuit Breaker). SCBs are connected by wireless technologies with battery backup, and set their power capping based on the indication issued by central manager. The central manager computes power capping threshold of each SCB using the proposed algorithm, in real-time fashion. Experimental results show that the proposed algorithm can optimize the required capacity of the local power generator and that we need a feedback-looped adaptive threshold calculation algorithm

Reliability and delay analysis of slotted anycast multi-hop wireless networks targeting dense traffic iot applications

Studies on IEEE 802.15.4 MAC in the current literature for anycast multi-hop networks do not capture a node's behaviour accurately. Due to the inaccurate modeling of state-wise behaviour of a node, the optimization of network parameters has not been efficient so far. In this work, we include the state-wise behaviour of a relay node into a 3D Markov model to more accurately investigate the protocol performance. Performance analysis of the proposed analytical model is evaluated for different variants of active state length, packet length and wake up rates considering reliability and delay as key performance metrics. Performance analysis shows that the model captures the behaviour of relay nodes most accurately

Real Time Net Zero Energy Building Energy Manager with Heterogeneous Wireless Ad hoc Network Adaptable To IoT Architectures

Significant energy consumption by buildings from utility grid has made researchers revisit existing Building Energy Management Systems (BEMS). Most of the developing countries have taken a green initiative of Net Zero Energy Buildings (NZEB) to reduce carbon foot print and fast depletion of conventional energy sources. Though the integration of solar and wind based systems to grid is successful in recent years, residential building energy management systems with renewable energy sources is still an evolving research area. Monitoring, control and actuation systems should be tightly coupled with the help of any to any device communication namely Internet of Things (IoT) to realize an efficient NZEB. In this paper a real time NZEB is proposed and developed with bi-directional wireless sensor and actuation system. Proposed NZEB central server collects and maintains a database of on site solar generation, battery state of charge and load power consumption data of a building with help of IEEE 802.15.4 and IEEE 802.11 wireless networks. Proposed system was deployed as a test bed with sensing, control, actuation and server modules and connecting them with a bi-directional wireless network architecture similar to IoT. Data observed at experimental test bed confirm that developed system can estimate on site solar power generation, state of charge on battery bank and load power consumption with negligible error. A simulation study with experimental data collected at NZEB test bed shows that NZEB can optimally schedule loads between local generation and utility grid thereby minimizing peak demand on the grid