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Queuing Theory Approach for Evaluating Rate of Transmission in Wireless Network Using Network Coding
Get PDFDue to the rapid development in the transmission of Wireless Network technologies, the need for rate evaluation using network coding demands urgent attention. This is solely dependent on how to improve on high performance communication channels for user’s interest. In this paper, an approach of using queuing theory in a wireless network is presented. The idea of network coding in a wireless environment address the transmission of packets not only in unicast form but also address the conflict in packet movement across a channel. Network coding also contributes greatly in computer communication system and other computer based electronic appliances. This means that a source is transmitting packets to a particular destination according to the user’s needs in a communication system. Packet transmission is enhanced within the wireless network using queuing theory. In this approach, the first routers are set to be the user access router and another directly connected router is set to be the source router. The user access router is set to connect 11 number of other routers where mainly the network coding is conducted. The results show an improvement in transmission rate by applying network coding as compared to other scenarios where networks coding are not utilized or the conventional routing either
Potential Impact of Cypermethrin on Selected Groups of Soil Microorganisms
Get PDFApplication of cypermethrin as insecticide during agricultural practices
is a global concern due to its toxicity and potential accumulation of its
metabolites in the aquatic environment. A mesocosm plot of agricultural land
(500 m2) was demarcated and deliberately contaminated with cypermethrin to
study its impact on the autochthonous microorganisms. Potential effects of 3-
phenoxybenzoic acid (3-PBA), a known suicide metabolite of cypermethrin,
on hydrolytic activities were also investigated by using fluorescein diacetate
assay (FDA). A significant increase in the abundance of total heterotrophic
bacteria from 3.55 x 106cfu g-1to 1.30 x 108cfu g-1in 12 weeks as against the
control was induced by the insecticide in the mesocosm. The number of
starch hydrolysing bacteria increased after the second insecticide treatment
from 6.25 x 106cfu g-1to 2.70 x 107 cfu g-1in three weeks. However, there was
no significant increase in the microbial count of fungi, presumptive
actinomycetes and nitrogen fixing bacteria during the twelve weeks of
experiment. The hydrolytic activity of soil microorganisms was apparently
inhibited insoil treated with different concentration of 3-PBAthan in untreated
soil. These results suggest that the application of a commercial cypermethrin
formulation increased the abundance of selected soil microorganisms while3-
PBA reduced the soil microbial hydrolytic activity
In vitro Degradation of Extracted Cassava Linamarin by Bacillus Species Isolated from cassava wastewater
Get PDFLinamarin is the most abundant cyanoglucoside present in cassava cells and may generate the equivalent amount of hydrocyanic acid. This study was aimed to assess degradative capacities of Bacillus pumilus strain WOB3 and WOB7on linamarin. The test organisms for linamarase activity were identified on the basis of phenotype, biochemical properties and 16S rDNA gene sequencing as: Bacillus pumilus strain WOB3 KX774195 and Bacillus pumilus strain WOB7 KX774196. Growth studies showed that the strains grew in all the substrates tested. The doubling times of Bacillus pumilus strain WOB3 and Bacillus pumilus strain WOB7 were 8.25 d and 7.53 d on cassava effluent, 6.30 dand 5.78 d on supplemented cassava effluent, 8.66 dand 9.90 d on waste leachate and 6.30 d and 9.24 d on supplemented waste leachate respectively; with specific growth rates of 0.084 d-1 and 0.092 d-1 on cassava effluent, 0.11 d-1 and 0.12 d-1 on supplemented cassava effluent, 0.080 d-1 and 0.070 d-1 on waste leachate and 0.11 d-1 and 0.075 d-1 on supplemented waste leachate respectively. High-performance liquid chromatographic analysis studies revealed that linamarin degradation by the strains followed a linamarase pathway involving CO2 and HCN as metabolic intermediates. Based on HPLC analysis, linamarin residual concentration at day 12 by the strains WOB3 and WOB7 was 26.73 mgL-1(19.79 %) and 29.79 mgL-1 (21.92 %). These novel features make the bacteria suitable candidates for in-situ application on sites contaminated with cassava processing wastes
Prediction of dry ice mass for firefighting robot actuation
Get PDFThe limitation in the performance of electric actuated firefighting robots in hightemperature fire environment has led to research on the alternative propulsion system for the
mobility of firefighting robots in such environment. Capitalizing on the limitations of these
electric actuators we suggested a gas-actuated propulsion system in our earlier study. The
propulsion system is made up of a pneumatic motor as the actuator (for the robot) and carbon
dioxide gas (self-generated from dry ice) as the power source. To satisfy the consumption
requirement (9cfm) of the motor for efficient actuation of the robot in the fire environment, the
volume of carbon dioxide gas, as well as the corresponding mass of the dry ice that will
produce the required volume for powering and actuation of the robot, must be determined. This
article, therefore, presents the computational analysis to predict the volumetric requirement and
the dry ice mass sufficient to power a carbon dioxide gas propelled autonomous firefighting
robot in a high-temperature environment. The governing equation of the sublimation of dry ice
to carbon dioxide is established. An operating time of 2105.53s and operating pressure ranges
from 137.9kPa to 482.65kPa were achieved following the consumption rate of the motor. Thus,
8.85m3 is computed as the volume requirement of the CAFFR while the corresponding dry ice
mass for the CAFFR actuation ranges from 21.67kg to 75.83kg depending on the operating
pressure
Development and performance evaluation of an effective dryer for poundo yam flour processing plant
No full textThe process of making pounded yam, from yam, Dioscorea spp., which is
mostly consumed by people of sub-Sahara region as source of carbohydrate is energy consuming, therefore, the pounded yam flour, commonly called poundo yam,
through which pounded yam is prepared faster and easier, has become popular in
West Africa. Although there is an existing niche market for the design and production of poundo yam processing plant, proper drying, one of the most important
stages in the production line of poundo yam flour is drying to remove moisture from
parboiled (a stage before drying) yam chips still remains the limitation to an effective application of the processing plant in the food industry. The development and
performance evaluation of an effective drier that will allow the movement of the
dried yam chips to the next machine in poundo yam process plant and its suitability to the food industrial applications was carried out in this research. The volume
of the drying drum was estimated to be 0.03 m3
. The capacity of the dryer is the
amount of yam the drying drum can contain per batch. 28 kg of yam chips was dried
at a temperature of 50°C for 3.7 h being the safe drying temperature. The efficiency
of the machine was evaluated by estimating the moisture removal rate from the
yam in comparison with the power consumption rate and this gave 72.71%
Performance Study of University of Ado Ekiti (UNAD) Transit Shuttle Buses
Get PDFTraffic engineering uses engineering methods and techniques to achieve the safe and time efficient movement of
people and goods on roadways. The safe and time efficient movement of people and goods is dependent on the transit system
performance, which is directly connected to the traffic characteristics. The main parameters of performance of transport
shuttles are traffic volume, speed, density and revenue; and all these are evaluated in this study. In the absence of effective
planning and traffic management, current road infrastructure will not be able to cater for the future needs of the University.
Students, staff and vehicle volumes have increased significantly in the last decade in the Institution, yet the performance of the
transport shuttle have been dismal and unable to achieve its objectives. Findings of the study show that the morning peak
period (8.00am to 9.00am) has 234 vehicles/hr, evening peak period (2.00pm to 3.00pm) has 284 vehicles/hr, while the offpeak period (11.00am to 12.00pm) has 156 vehicles/hr. The journey time from the Post Office bus stop to the University
campus, measured as 34.01 minutes, was too long for the distance of 15.0km road which according to the Nigeria Highway
Code should not be more than 18 minutes. The average stopping time was 6.55 minutes, average interval between arrivals of
motorists was 16.40 seconds, the average queue length was 14.23 people, and the average waiting time at the bus-stop 4.17
minutes. These values were obtained using the queuing theory and shows much commuters time is lost on transit queues. The
financial condition of the transit unit shows that amount generated is less than the amount expended by the transit operators.
This means, in effect, that the shuttle bus operators are operating in deficit
Biodegradation of selected polycyclic aromatic hydrocarbons by axenic bacterial species belonging to the genera Lysinibacillus and Paenibacillus
Get PDFThe quest for competent degraders of recalcitrant polynuclear aromatic hydrocarbons (PAHs) for use in
sustainable bioremediation technology has justified the execution of this work. In this study, three bacterial strains (FB-1, FB-2 and FB-3) were isolated from a former industrial site in Bloomington, Indiana. The catabolic
versatility of these obtained strains was evaluated on some
selected PAH-naphthalene, anthracene, fluoranthene and pyrene. Using the 16S rRNA sequencing analyses, our strains belonged to the family Firmicutes whereby strain FB-1 was identified as Lysinibacillus sp. FB-1, strain FB-2 as Bacterium FB-2 and strain FB-3 as Lysinibacillus fusiformis FB-3. The biodegradation of the selected PAHs was determined using gas chromatography, and the calculated percentage utilization of the selected PAHs varied between 97 and 4%. We further determined the mean biodegradation rates for fluoranthene when supplemented with molasses. The mean biodegradation rates were between (mg L-1 ) 0.214 ± 0.006 and 0.318 ± 0.002, while MSfluoranthene only ranged from (mg L-1) 0.210 ± 0.056 to 0.437 ± 0.176. However, with ANOVA at 5% (P\0.05) there seemed to be no significant difference in the mea
Development of hybrid artificial intelligent based handover decision algorithm
Get PDFThe possibility of seamless handover remains a mirage despite the plethora of existing handover algorithms. The underlying factor responsible for this has been traced to the Handover decision module in the Handover process. Hence, in this paper, the development of novel hybrid artificial intelligent handover decision algorithm has been developed. The developed model is made up of hybrid of Artificial Neural Network (ANN) based prediction model and Fuzzy Logic. On accessing the network, the Received Signal Strength (RSS) was acquired over a period of time to form a time series data. The data was then fed to the newly proposed ahead ANN-based RSS prediction system for estimation of prediction model coefficients. The synaptic weights and adaptive coefficients of the trained ANN was then used to compute the ahead ANN based RSS prediction model coefficients. The predicted RSS value was later codified as Fuzzy sets and in conjunction with other measured network parameters were fed into the Fuzzy logic controller in order to finalize handover decision process. The performance of the newly developed ahead ANN based RSS prediction algorithm was evaluated using simulated and real data acquired from available mobile communication networks. Results obtained in both cases shows that the proposed algorithm is capable of predicting ahead the RSS value to about ±0.0002 dB. Also, the cascaded effect of the complete handover decision module was also evaluated. Results obtained show that the newly proposed hybrid approach was able to reduce ping-pong effect associated with other handover techniques
Physiological behavior of newly isolated Bacterium CB1 and Stenotrophomonas maltophilia strain CB2 on Chrysene, Pyrene, Naphthalene and Fluoranthene
Get PDFThe biodegradability of some polycyclic aromatic hydrocarbons were studied in liquid culture media using bacterial strains (Bacterium CB1 and Stenotrophomonas maltophilia strain CB2) isolated from a former industrial site contaminated with organic and inorganic contaminants. The enrichment experiment was done with chrysene. The partial 16S rRNA gene analyses of Bacterium CB-1 possessed 100% similarity to an uncultured bacterium clone nbt020a while Stenotrophomonas maltophilia strain CB2 had 99% similarity to Paenibacillus sp. Y412MC10. Bacterium CB1 and Stenotrophomonas maltophilia strain CB2 degraded naphthalene between the range of 27% and 42%, chrysene 47% and 12%, fluoranthene 5% and 16%, pyrene 12% and 17% respectively. The strains utilized the test compounds as sole source of carbon and energy. As anticipated, the controls (abiotic and killed) losses were insignificant. The residual PAH obtained in some cases correlated to an increase in cell number indicating that our strains were responsible for the degradation
Pectinase production by Bacillus megaterium, Bacillus bataviensis, and Paenibacillus sp. isolated from decomposing wood residues in the Lagos lagoon
Get PDFThree wood decomposing bacteria isolated from the Lagos lagoon, Bacillus megaterium, Bacillus bataviensis and Paenibacillus sp. were screened for their pectinase producing abilities using pectin as substrate under submerged fermentation (SMF) conditions. The results showed that all three isolates produced appreciable pectinolytic activities. Paenibacillus sp. showed the highest pectinase activity when compared with the other two isolates. The optimum pH for pectinase activity for both B. megaterium and B. bataviensis was 8.0 while it was 6.5 for Paenibacillus sp., B. bataviensis, and B. megaterium showed optimum pectinase activity at 60°C and Paenibacillus sp. at 40°C. Metal ions such as Na+ and K+ improved the activity of pectinase produced by the three isolates when compared to the effect of Zn2+ and Mn2+. The molecular weights of the enzymes were also estimated by gel filtration as 29,512 da, 32,359 da, and 25,119 da for Paenibacillus sp., B. megaterium and B. bataviensis respectively. The study has provided a platform for further investigation into the biochemical characterization of the enzyme, and optimization of culture conditions to scale up pectinase production for commercial exploitation