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Search Results: 1 - 10 of 167639 matches for " Donatus E. Baasey "
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Impact of Element Spacing on the Radiation Pattern of Planar Array of Monopole Antenna  [PDF]
Ofem U. Omini, Donatus E. Baasey, Sulaiman A. Adekola
Journal of Computer and Communications (JCC) , 2019, DOI: 10.4236/jcc.2019.710004
Abstract: In recent years, several attempts have been made in designing planar array antennas with high directivity. This paper is aimed at investigating the impact of element spacing on the directivity of planar array of monopole antenna. The directivity of antenna with reduced grating lobes can be obtained by carefully varying the inter-element spacing of array antenna. Based on this conception, this paper presents the investigation carried out on the relationship between inter-element spacing and the directivity of planar array of monopole antenna. It went further to highlight the effect on the total fields radiated by the antenna. The inter-element spacing is one of the most important antenna parameters that determine the directivity of the antenna. For a planar array of monopole, the directivity can be improved by varying the inter-element spacing. Four elements uniform planar array antenna and Hadamard matrix method was used to determine element positioning in the array matrix. The simulated results obtained using Matlab, showed that good directivity was obtained by using element spacing between 0.1λ - 0.5λ. Increasing the spacing beyond 0.6λ - 1.0λ also improved the directivity, but generated many grating lobes. As inter-element spacing increased, the grating lobes increased in size, number and levels. The study, therefore, inferred that the best directivity (radiation pattern) can only be obtained when the element spacing is within 0.1 - 0.5λ.
Productivity and Efficiency of Nigeria s Seaports: A Production Frontier Analysis
E. Onwuegbuchunam Donatus
International Business Management , 2012, DOI: 10.3923/ibm.2012.41.46
Abstract: Productivity and efficiency are key expectation of every production decision. Estimation of a port s production frontier is therefore critical in the assessment of port s productivity and efficiency. In this study, the production function of Nigeria s seaport is modeled using the Stochastic Frontier Framework. Panel data analyzed consists of records on eight coastal ports with details on output and multiple input variables covering a period of 22 years. The analysis reveals that total factor productivity of the ports averages >2.5 million ton per annum and 3 of them operate below frontier. In addition, capital inputs variables are found to significantly contribute to port productivity while labour input variable which represents manual cargo handling effort in the ports is found statistically insignificant. Thus, total mechanization of cargo handling operation, especially in developing and transition countries ports to boost port infrastructure productivity and efficiency is again supported in the Nigeria s case.
Productivity and Efficiency of Nigeria s Seaports: A Production Frontier Analysis
C. Ibe Callistus,E. Onwuegbuchunam Donatus
International Business Management , 2012, DOI: 10.3923/ibm.2011.382.387
Abstract: Productivity and efficiency are key expectation of every production decision. Estimation of a port s production frontier is therefore critical in the assessment of port s productivity and efficiency. In this study, the production function of Nigeria s seaport is modeled using the stochastic frontier framework. Panel data analyzed consists of records on eight coastal ports with details on output and multiple input variables covering a period of 22 years. The analysis reveals that total factor productivity of the ports averages >2.5 million tons annum-1 and three of them operate below frontier. In addition, capital inputs variables are found to significantly contribute to port productivity while labour input variable which represents manual cargo handling effort in the ports is found statistically insignificant. Thus, total mechanization of cargo handling operation, especially in developing and transition countries ports to boost port infrastructure productivity and efficiency is again supported in the Nigeria s case.
A Modified Averaging Composite Implicit Iteration Process for Common Fixed Points of a Finite Family of k-Strictly Asymptotically Pseudocontractive Mappings  [PDF]
Donatus Igbokwe, Oku Ini
Advances in Pure Mathematics (APM) , 2011, DOI: 10.4236/apm.2011.14036
Abstract: The composite implicit iteration process introduced by Su and Li [J. Math. Anal. Appl. 320 (2006) 882-891] is modified. A strong convergence theorem for approximation of common fixed points of finite family of k-strictly asymptotically pseudo-contractive mappings is proved in Banach spaces using the modified iteration process.
Nation Branding: An Analysis of Botswana’s National Brand
Edward E. Marandu,Donatus N. Amanze,Tirubaza C. P. Mtagulwa
International Journal of Business Administration , 2012, DOI: 10.5430/ijba.v3n2p17
Abstract: This paper evaluates Botswana’s national branding using the Gilmore (2002) and the Echtner & Ritchie (2003) models. The methodology involved an examination of the extant literature to identifying key factors that influence brand perceptions for a nation and the nature of those factors. The findings showed that the Botswana branding incorporated most of the variables depicted in the Gilmore model. The nature of the variables chosen were also consistent with the Echtner and Ritchie model in the sense that it made use of functional and psychological characteristics and combined them in a holistic manner to come up with the slogan “our pride, your destination”. The paper advises future researcher to empirically test the robustness of the Botswana brand in terms of its effectiveness on the ground.
The Beam-Forming Technique for Enhancement of Noisy Seismic Refraction Data  [PDF]
Arewa James Ogah, Ani Donatus Chinedu
International Journal of Geosciences (IJG) , 2012, DOI: 10.4236/ijg.2012.324087
Abstract: We have described a method of obtaining useful information from noisy seismic refraction data. The simple method, tagged beam-forming technique, is based on the basic time-distance equations of refraction seismology. It involves basically of introducing relative time delays to individual seismic traces of seismic refraction spread to correct for the non-coincidence of the incidence seismic energy at different geophones, and averaging the traces to obtain the beam. The assumption here is that the signal is coherent between the geophones while the noise is random, and for groups of geophones corresponding to the same refraction segments of the travel time curve, this basic assumption is valid. The process of beam forming therefore leads to improvement in signal-to-noise ratio (SNR) and correct determination of the intercept times which are subsequently used to compute other geologic layer parameters. The ability of the applied technique to filter out or minimize random noise has been tested using a modified random number routine. The performance test on computation of geologic layer parameters using very noisy synthetic data reveals that the method is still very reliable even with very poor quality data having SNR as small as 0.05.
The Qualitative Dermatoglyphics PATTERNS in Both Hands for Males and Females in Ubang Clan Cross River State Nigeria  [PDF]
Andrew Donatus Abue, Rose Christopher, Adebisi Sunday
Advances in Anthropology (AA) , 2018, DOI: 10.4236/aa.2018.82004
Abstract: Dermatoglyphics patterns otherwise known as toe or fingerprints are defined as the scientific study of fingerprints or toe prints. This started in 1892 when one of the most original biologists of his time, Sir Francis Galton, a cousin of Charles Darwin published his now classic work on fingerprints. The Ubang community has a total population of about four thousand, six hundred (4600) people (2006 Census figures). They are four autonomous communities vizOkweriseng, New Jerusalem, Ofambe and Okiron. Their dominant religion is traditional religion and Christianity. They are mostly peasant farmers, located at the foot of the Obudu hills in Obudu LGA of Cross River State, Nigeria.This is an amazing Anthropological community where the Men speak Ofre and the women speak Arasere. The researchers were looking out for exceptional dermatoglyphics feature very unique to this community probably because of the unique language variation observed in the community. The researchers also aimed at establishing the qualitative dermatoglyphic features for the community. The ink procedure established by Cummins was adopted in collecting the prints on the palms and fingers of the selected sample size. A total of 800 persons were used for the research (400 males, 380 females and 20 samples were discarded). Inclusion and Exclusion criteria were used to select samples. The simple random sampling method was used in selecting the clusters and the subjects. Data were analyzed using SPSS for windows version 21 (IBM Corporation WY, USA) and Statistical Analysis System, SAS JMP10, user guide statistics, version 10 edition, SAS Institute Inc.
Analyses of Dermatoglyphic Patterns in Ntamante, Boki Local Government Area (LGA) of Cross River State, Nigeria  [PDF]
Andrew Donatus Abue, Christopher Rose, Nappier Courage
Advances in Anthropology (AA) , 2018, DOI: 10.4236/aa.2018.83005
Abstract: Analysis of the dermatoglyphics pattern in Ntamante Boki LGA of Cross River State, South-South, Nigeria is a research work carried out with the sole aim of analysing the dermatoglyphics pattern of the Ntamante people of Boki LGA in Cross river. Two hundred persons were randomly selected for the research comprising male and females. The collection of the finger prints was done using the ink procedure described by Cummins and Midlo analysis of data that was done using SPSS. The result obtained was thus: for females, the mean standard deviation was least in the radial loop (1 ± 1.6), followed by the Arches (4.9 ± 3.8), the Whorls (6.4 ± 4.4) and highest on the Ulnar loop (9.1 ± 9.7). Variables measured differed significantly (p = 0.05) with a Chi-square (X2) value of 17.41. Pr > Chisq = 0.053. For males, the mean standard deviation was highest in the Ulnar Loop pattern (12.6 ± 9.2), followed by the arch pattern (4.7 ± 2.8), then the whorls (3.3 ± 3) and then the radial loops (0.1 ± 0.4). This index study shows a higher frequency distribution of patterns of the Ulnar Loop, followed by the arches, then the whorls and finally the radial loop in the male samples which is different from the usual trend of Ulnar loop > Whorls > Arches > Radial loop obtained in other ethnic groups in Nigeria following the work of Jaja et al. among the Ijaws, Ekanem et al. amongst the Annangs, Ujaddughe et al. amongst the Esan of Edo state. Sexual dimorphism was evident in this research work with males showing a higher Ulnar loop distribution (12.6 ± 9.2), while the female percentage frequency distribution was (9.1 ± 9.7). In conclusion, this study shows the percentage frequencies of patterns among the Ntamante with the Ulnar Loop >Arch > Whorls> Radial loop amongst the males. Amongst the females, this was the distribution of pattern: Ulnar Loop > Whorls > Arches > Radial Loop. This is in line with what was obtained in different ethnic groups in Nigeria with regards to the percentage frequency distribution in the females, while amongst the males, the distribution shows the distribution pattern in Asia and Europe.
Antidepressant Effects of Mallotus oppositifolius in Acute Murine Models
Kennedy K. E. Kukuia,Priscilla K. Mante,Eric Woode,Elvis O. Ameyaw,Donatus W. Adongo
ISRN Pharmacology , 2014, DOI: 10.1155/2014/324063
Abstract: Objective. Hydroalcoholic extract of leaves of Mallotus oppositifolius (MOE), a plant used for CNS conditions in Ghana, was investigated for acute antidepressant effects in the forced swimming (FST) and tail suspension tests (TST). Results. In both FST and TST, MOE (10, 30, and 100?mg?kg?1) significantly decreased immobility periods and frequencies. A 3-day pretreatment with 200?mg?kg?1, i.p., para-chlorophenylalanine (PCPA), a tryptophan hydroxylase inhibitor, reversed the decline in immobility and the increase of swimming score induced by MOE in the modified FST. Pretreatment with reserpine alone (1?mg?kg?1), α-methyldopa alone (400?mg?kg?1, i.p.), or a combination of both drugs failed to reverse the decline in immobility or the increase in swimming score caused by the extract in the modified FST. The extract potentiated the frequency of head twitch responses induced by 5-hydroxytryptamine. Pretreatment with D-serine (600?mg?kg?1, i.p.), glycine/NMDA agonist, abolished the behavioural effects of MOE while D-cycloserine (2.5?mg?kg?1, i.p.), a glycine/NMDA partial agonist, potentiated it in both TST and modified FST. Conclusion. The extract exhibited antidepressant effects in mice which is mediated by enhancement of serotoninergic neurotransmission and inhibition of glycine/NMDA receptor activation. 1. Introduction Depression is an extremely common pathological complex with psychological, neuroendocrine, and pathological symptoms [1]. It is a leading cause of disability worldwide and has a very significant impact on morbidity, mortality, and health care cost [2–4]. Disconcertion in monoaminergic neurotransmission especially serotonin and noradrenaline neurotransmission is considered the major cause of the observed symptoms of depression. Unfortunately the efficacy of these medications is unsatisfactory and multiple side effects are common [5]. It is estimated that about 40% of patients have conditions refractory to current medications. Furthermore, these drugs require at least 2–4 weeks of administration before producing clinically meaningful improvement in the symptoms [6]. These reasons underpin the need for novel therapeutic agents with less side effects and faster onset of action [7, 8]. Also both preclinical and clinical studies support the role of NMDA receptor antagonists as possible therapeutic agents for depression [5, 9, 10]. For instance ketamine and memantine have demonstrated rapid and profound antidepressant effects clinically [11, 12]. Numerous behavioural studies have further demonstrated that antagonists and partial agonists at the
Development Efforts Of Oil Companies As Perceived By Rural Households In Selected Oil Producing Communities Of Rivers State, Nigeria
Matthew Ukpongson, Donatus Onu
Journal of Agriculture and Social Research (JASR) , 2004,
Abstract: A total of 120 respondents participated in the study to determine the perceptions of rural households toward oil companies' efforts to reach the hosts (rural dwellers) in 40 randomly selected oil-producing communities of Rivers State. Findings indicated that a lot of efforts have been geared by oil companies to reach their hosts (rural communities) however, 50% of the respondents agreed that such efforts are inadequate and ill-distributed to meet the expectations of the people. About 90.8% of the respondents disagreed that the host communities are highly satisfied with companies' efforts (projects and services) to them. Based on these findings, recommendations were made.
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