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Border Gateway Protocol to provide failover in multihoming environment
Get PDFNowadays Internet access across the globe is very crucial because of the huge size of useful data
that the Internet stores. This stimulates most ISPs to choose a reliable routing protocol in order to
preserve the security and guarantee of customer’s data on the Internet. By multi-homing a network
using BGP, a more control of balancing the traffic load and achieving redundancy becomes
possible. This will enhance network performance, quality throughput and better routing policies
on the Internet. Single-homed Internet communication link between networks’ Internet service
provider does not inspire with confidence because of excessive traffic and device or human error
that may arise. We use BGP because of its ability to choose the best path to a destination
particularly in a Multihoming environment. Our simulation results are achieved using GNS3
emulator and Wireshark network analyser. We carried out two simulations to run BGP
Multihoming to the same service provider and to different service provider. In both scenarios we
run the simulations in failover mode and in load-shearing mode. Simulation results show that BGP
Multihoming to different service providers provides failover to ISP networks. For a home and
enterprise network to have a certain level of failover or redundancy there is a need to employ the
use of BGP Multihoming to different service provider
Experimental Investigation of Lard and Tallow Oils Suitability in Turning Operation of Hypo-Eutectoid Steels
Get PDFThis research is aimed at evaluating the performance suitability of lard and tallow based cutting fluids as potential cutting fluids in turning of hypo-eutectoid steels using carbide cutting tool steels. This was achieved via investigation of the effect of those selected fluids on certain parameters like tool temperature, tool life, spindle power consumption, Work-piece under roughness and chip formations etc., as compared to the conventional mineral oil-based MCFs.Cooling and lubrication in machining are important in reducing the severity of the contact processes at the cutting tool-workpiece interface. Currently, there are wide scale evaluations of the use of metal working fluids (MWFs) in machining, so as to reduce the amount of lubricants in metal removing operations. The increasing awareness of the general public on the environment and health impact of mineral oil-based metal cutting fluids (MCFs) is forcing machine workshop operators to reduce their use as cutting fluids and in search for more environmental friendly animal oil-based cutting fluids. Based on this, commercially available animal oils are currently been exploited as potential oils for formulation of animal oil-based cutting fluids. It is therefore necessary to conduct machining trials to determine the suitability of these oils in metal cutting operations such as turning, drilling and milling etc. This study investigates the effect of the selected cutting fluids on certain machining parameters in turning operations of hypo-eutectoid steels using carbide cutting tool. The selected oils purchased from a local market in Ibadan, Nigeria were sieved to remove any foreign particles or dirt. The solution (water, additives, and base-oil) were mixed at an elevated temperature of 55oC in a proportion 5:1:2.The essence of the emulsifier (additive) was to prevent separation of water from oil. The steel samples obtained from a steel company in Nigeria after spectrochemical analysis, were machined on a variable speed center lathe under different machining parameters. Experimental results clearly showed that Conventional cutting fluid might be replaced with Non-conventional one like LOCFs and TOCFs as they give better performances. With slight modifications and deliberate but careful alterations in some of the components of such oils, better performing cutting fluids could be obtainedSelf-Sponsore
A case analysis on the adequacy of work-life balance practices in UK small-and medium-sized enterprises
Get PDFThe purpose of this study is to examine whether work-life balance (WLB) practices are satisfactorily provided in UK small and medium-sized enterprises (SMEs) and the impact of the availability of these work-life policies on turnover intentions. A review of extant literature reveals scarce knowledge in this area of research and this study presents a rudimentary effort to fill this gap.Research Design & Methods: Using qualitative design, the data set comprised of in-depth interviews with thirty-six employees working in small and medium-sized UK convenience stores and supermarkets with less than ninety employees.Findings: Informal nature of human resource management policies emerged from the findings as one of the constraining forces impeding work-life agendas in SMEs and causing low staff retention in UK. Although other themes were found to contribute to retention challenges, however, these additional reasons were not independent, but all considered integrated.Implications & Recommendations: Consequently, the practical implication of devising ways to overcome WLB and retention deficiencies in this context were also explored.Contribution & Value Added: The originality of this work lies in studying the importance of WLB practices to some of these grass root businesses that make up a large proportion of the economy in the UK. As the limitation of this study is that it is wholly qualitative in nature, it is suggested that future research should rely on quantitative designs that provides more internally valid tests via computational techniques
Contexts and Proximisation Features in President Muhammadu Buhari’s Speech on Regional Security in West Africa
Get PDFThis paper complements the pragmatic attempts in its adoption of Auer’s contextual model and
Cap’s proximisation theory in carrying out a context-driven and discourse space pragmatic
analysis to track the speaker-imposed construal distance and proximity in political discourse on
security. President Buhari’s speech at the 2nd regional security summit delivered on the 14th
May, 2016 has been purposively selected for this exploration. The study identified three contexts
namely securitisation, rehabilitation and solidarity within which President Buhari seeks
legitimization by using spatial, temporal and axiological proximisation features in the
representation of the actors involved. The study identified pragmatic usage of verb phrases as
category accommodating markers and the symbolic movement between the discourse space
centre inside-the-deictic centre noun phrases and discourse space periphery outside-the-deictic
centre noun phrases is used by the speaker to achieve his vantage intentions. The study also
found out that the President deployed lexico-grammatical expressions to label Boko Haram
against the ideologies of extremist, terrorist, and killer. The study concludes that President
Buhari’s orientation to shared situational knowledge and mutual contextual belief within the
social context of securitisation, solidarity and rehabilitation imply that African politicians’ use of
language on war on terror promotes solidarity, galvanise support of the general public by
legitimising actions against insurgency or terrorism with a view to curbing the menace
Empirical Assessment on Financial Regulations and Banking Sector Performance
Get PDFThis study examines financial regulation and banking sector performance in Nigeria. Specifically, the study determines the impact of reforms on banking sector performance and also assesses the nexus between capital adequacy and banking sector performance. Time series data for the period 1993 to 2014 was used. As an analytical tool, the study uses unit root test to determine the stationary state of the variables. We also employed the Johansson co-integration and error correction model (ECM) statistical techniques to establish both short-run and long-run dynamic relationships between the endogenous and exogenous variables. The empirical findings indicate that financial regulation significantly impacts the banking sector performance while financial regulation has both short-run and long-run dynamic relationships with the banking sector performance in Nigeria. It was found that the four-period lag of capital adequacy negatively affects banking sector performance and is not statistically significant. The paper suggests that the Central Bank of Nigeria (CBN) should continually make public the impacts that the various financial regulations and reforms have on the performance of Nigerian banks. Majority of the policies on financial regulation by the apex bank (CBN) need to be long-run which can
enable confidence of stakeholders, shareholders and the general public in the Nigerian banking industry when critically evaluated
Isolation, Molecular Characterization and Antibiotics Susceptibility Pattern of Methylotrophic Bacteria Occuring in the Human Mouth
Get PDFMethylotrophic bacteria are ubiquitous bacteria that are capable of using one carbon compounds such as methane, methanol, halogenated methane, and methylated amine as sources of carbon and energy for their diverse metabolic activities. Methylotrophic bacteria were isolated from the tongue, and supra-and subgingival plaque in the mouths of volunteers and patients with periodontitis. The isolation, identification, antibiotic susceptibility pattern and molecular characterization of methylotrophic bacteria from 150 volunteers and patients with periodontitis were done using standard method. Nutrient agar fortified with methylamine as a growth factor was used to aid the growth of these bacteria. The result show that a total of twelve (12) bacteria were identified. These are Bacillus licheniformis, Neisseria flava, Neisseria meningitis, Micrococcus flava, Pseudomonas aeruginosa, Streptococcus pneumoniae, Methylobacteria radiotolerance, Methylotrophic thiocynatum, Methylococcus capsulatum, Methylotrophic rubra and Branhamella catarhalis. The antibiotics susceptibility test showed that B. licheniformis, N. meningitis and P. aeruginosa exhibited the highest resistance against the antibiotics. The 12 bacteria were characterized molecularly with Polymerase chain reaction PCR amplified method using primers for the virulence genes of Methylotroph. The mxaF gene of methanol dehy-drogenase MxaF was detected in 3 bacteria: pilc of pilin gene in 3 bacteria, stx1 of shiga toxin nana of neuraminidase and pila of pilin gene was detected in all the bacteria. The results obtained in this research showed that methylotrophs may be responsible for periodontitis and that healthy people are carriers
Pyrene Biodegradation Potential of an Actinomycete, Microbacterium Esteraromaticum Isolated from Tropical Hydrocarbon-Contaminated Soi
Get PDFA novel pyrene-degrading actinomycete, phylogenetically identified as Microbacterium esteraromaticum strain SL9 was isolated from a polluted hydrocarbon-contaminated soil in Lagos, Nigeria. Growth of the isolate on pyrene was assayed using total viable counts, pyrene degradation was monitored using gas chromatography (GC-FID) while UV-Vis spectrophotometry was used to detect metabolites of pyrene degradation. The isolate tolerated salt concentration of up to 6%, grew luxuriantly on crude oil and exhibited weak utilization of fluorene, acenaphthene and engine oil. It resisted cefotaxime, ciprofloxacin and amoxicilin, but was susceptible to meropenem, linezolid and vancomycin. It also resisted elevated concentrations of heavy metals such as 1-5 mM lead and nickel. On pyrene, the isolate exhibited growth rate and doubling time of 0.023 h-1 and 1.25 h, respectively. It degraded 55.16 (27.58 mg L-1) and 89.28% (44.64 mg L-1) of pyrene (50 mg L-1) within 12 and 21 days respectively, while the rate of pyrene utilization was 0.09 mg L-1h-1. Catechol dioxygenase assay using UV-Vis spectrophotometry revealed the detection of meta cleavage compound, 2-hydroxymuconic semialdehyde in the crude cell lysate. The results of this study showed the catabolic versatility of Microbacterium species on hydrocarbon substrates and their potential as seeds for bioremediation of environments co-contaminated with polycyclic aromatic hydrocarbons and heavy metals
The degradation of coniferyl alcohol and the complementary production of chlorogenic acids in the growth culture of Streptomyces albogriseolus KF977548 isolated from decaying wood residues
Get PDFConiferyl alcohol is one of the major precursors of lignin; the most abundant aromatic compound and
a natural resource currently receiving attention because of the value-added metabolites resulting from
its degradation. Growth study of Streptomyces albogriseolus KF977548 (strain AOB) isolated from decaying wood residues in a tropical estuarine ecosystem was carried out using coniferyl alcohol as a sole
carbon source. Cell growth and metabolite production were monitored at 24 h interval by dry weight
measurements and HPLC, LC–MS-DAD analyses. Biochemical and PCR assays were carried out to detect
the major catabolic enzymes of interest. Strain AOB utilized coniferyl alcohol completely within 72 h
( = 0.204 h−1, Td = 3.4 h). Laccase and peroxidase were released into the growth medium up to 0.099
and 98 mol/mL respectively. Protocatechuate 3, 4-dioxygenase and demethylase were detected in the
genome whilst ortho-adipate pathway was clearly indicated. Growth on coniferyl alcohol or caffeic acid
as mono substrates resulted in the production of secondary metabolites identified by HPLC–MS as 1-
caffeoylquinic and 3,4,5-tricaffeoylquinic acids, known as chlorogenic acids, in the culture medium. The
microbial production of chlorogenic acids from a lignin-related substrate base by strain AOB could arouse
a plausible biotechnological process
Occurrence of hydrocarbon-degrading nitrogen-fixing bacteria in the rhizosphere of Paspalum vaginatum Sw.
Get PDFSeveral nitrogen-fixing and hydrocarbon utilizing bacteria were isolated from the rhizosphere of the turf grass Paspalum vaginatum Sw. using four different hydrocarbons; crude oil, decane, diesel and engine oil as substrates. The isolates showed between 98%-99% 16S rRNA gene similarity with species of Alcaligenes, Brevundimonas and Klebsiella. Only Alcaligenes faecalis C1B, Klebsiella varicola C3B and Klebsiella varicola C3BB had the nifH gene; and the genes responsible for nitrogen-fixing abilities of all the isolates were not plasmid borne. Three of the isolates, Brevundimonas diminuta C4B, Alcaligenes faecalis B5 and Alcaligenes faecalis D4A with the ability to grow well in crude oil as carbon and energy source were selected for further studies. Alcaligenes faecalis B5 had the highest growth rate constant of 0.038 µ-1 with a mean generation time of 18.46 h. Analysis of culture extracts by gas chromatography with flame ionization detector showed that Alcaligenes faecalis B5 degraded 90.5% of crude oil in 24 days, while Alcaligenes faecalis D4A and Brevundimonas diminuta C4B biodegraded 84.6% and 82.1% of the oil respectively. Confirmation of nitrogen fixing ability was determined by the acetylene reduction assay (ARA). Alcaligenes faecalis B5 produced the highest amount of ethylene (15.18 nmol) after 24 h of incubation, while Alcaligenes faecalis D4A and Brevundimonas diminuta C4B produced 12.10 nmol and 9.60 nmol of ethylene respectively. Nitrogen-fixing hydrocarbon utilizers are therefore potential seeds in the bioaugmentation of nitrogen-limited hydrocarbon-polluted environments
Analysis of Formant Frequencies of the Correct Pronunciation of Quranic Alphabets Between Kids and Adults
Get PDFIt is an obligation for a Muslim to become skilled and proficient in reciting Al-Quran considering that
Al-Quran is the fundamental source of revelation from Allah SWT. In Al-Quran, there are 28 alphabets where
each of them has their own unique sound. The Quranic alphabets produce sound that are characterized from
their point of articulation (Makhraj) and their characteristics (Sifaat). Knowing the correct way of pronunciation
through engineering perspective may help Muslim in learning Al-Quran, in the sense that the signal of the
experts can be used in Quranic teaching and learning as a reference model. Since both adults and children
possess different vocal tract, therefore there will be different outcomes of the pronunciation between both
experts. The features identification of the pronunciation of both experts is needed to represent the actual and
correct pronunciation that will be used as a reference for Quranic teaching and learning at later. In this paper,
the focus was on the identification and analysis of the correct pronunciation of the Quranic alphabets on the
data obtained from adults and children experts. The first and second formant frequencies (F1 and F2) were
used as the features where they were used to represent the pronunciation of each alphabet for both adults and
children category. The speech analysis software PRAAT was used to accomplish the pre-processing of the data using Spectral Subtraction technique and also used to measure the F1 and F2 values. Linear Discriminant
Analysis (LDA) was used for classification of the signals and results shows that some of the alphabets can be
identified uniquely using F1 and F2 features of the two categories