806 research outputs found
Investment prospects in inshore trawling in Nigeria
Commercial trawling for finfish in Nigeria's inshore water is a recent activity. Intensive industrial trawling started when the Federal Government distributed trawlers to viable fishermen cooperatives during the Third National Development Plan Period (1975-80). Hitherto, industrial fisheries development in the country focused on the assessment of the potential fish stock on Nigeria's continental shelf and measures to increase artisanal production. As a result of increasing demand for fish and shortage of foreign exchange to import fish, measures to increase fish supply leaned towards industrial exploitation of the fisheries potentials of Nigeria's continental shelf. Based on this background, this paper examines the investment prospects of trawling for fish in inshore waters. The fisheries potentials of the inshore zone of Nigeria are identified. Catch efficiency and profitability of inshore trawling are estimated. Measures that can safeguard the longterm interest of the trawling industry are recommende
Protein and amino acid requirements of warm-water fishes: a tool to efficient and low-cost fish feed production in Nigeria
Numerous investigations have utilized various semi-purified and purified diets to estimate the protein and amino acid requirements of several temperate fishes. The vast literature on the protein and amino acid requirements of fishes has continued to omit that of the tropical warm water species. The net effect is that fish feed formulation in Nigeria have relied on the requirement for temperate species. This paper attempts to review the state of knowledge on the protein amino acid requirements of fishes with emphasis on the warm water species, the methods of protein and amino acid requirement determinations and the influence of various factors on nutritional requirement studies. Finally evidence are presented with specific examples on how requirements of warm water fishes are different from the temperate species and used this to justify why fish feed formulation in Nigeria are far from being efficien
Comparative analysis of Polymer Electrolyte Membrane (PEM) fuel cells
Per-Fluoro-Sulphonic-Acid (PFSA) ionomers have been singled out as the preferable ionomers for making the Polymer Electrolyte Membrane Fuel Cells (PEMFC) membranes owing to their extensive intrinsic chemical stability and super sulfonic acid strength which is core to the PEMFC proton conductivity. This thesis presents a deeper analysis into these PFSA ionomer membrane electrode assemblies (MEA), presenting an electrochemical-analytical comparative analysis of the two basic types, which are the Long-Side-Chain (LSC) Nafion® and the ShortSide-Chain (SSC) Aquivion® ionomer MEA with emphasis on performance and durability which are currently not well understood. In particular, electrochemical circuit models and semiempirical models were employed to enable distinguishable comparative analysis. Also, in this thesis, we present a further probe into the effect of ionomer ink making processes, critically investigating the effect of the High Share Dispersion (HSD) process on both the Nafion® and Aquivion® ionomer membrane electrode assembly (MEA). The findings in this research provides a valuable insight into the performance and durability of PFSA ionomer membrane under various application criteria. The effect of operating parameters and accelerated stress testing (AST) on the PFSA ionomers was determined using electrochemical impedance spectroscopy (EIS) and electronic circuit model (ECM) analysis. The result of this study, shows that the ionomer ink making process for Nafion® and Aquivion® MEAs are not transferrable. Analysis of the PEMFC performance upon application of the high shear dispersion (HSD) process showed that Nafion® MEA had a 10.47% increase in voltage while the Aquivion® MEA had a 2.53% decrease in voltage at current density of 1.14A/cm2 . Also, upon accelerated stress testing, the Nafion® showed a 10.49% increase in its voltage while the Aquivion® on the other hand had a 7.16% decrease in voltage at 0.66A/cm2 . Thus indicating the HSD process enhances the performance of the Nafion® MEA and inhibits the performance of the Aquivion® MEA
Foraminiferal analysis of AE-1 well, Agbada formation Onshore, Western Niger Delta Basin: Implication for biozonation and age dating
Foraminiferal and sedimentological analysis was carried out using ditch cutting samples from intervals 2700 ft. - 10,185 ft. in AE-1 well. The samples were composited at 60 ft. into ninety four (94) ditch cutting samples. The standard micropaleontological sample procedures to recover the foraminiferal biofacies assemblages was utilized, followed by analysis and interpretation of the obtained results. The sedimentological analysis reveals five lithofacies - sandstone, sandy shale, shaly sand, mudstone and sandy clay which constitute part of the Agbada Formation of the Niger Delta. The foraminiferal fauna recovered from the samples studied comprised of twenty four species grouped into nineteen genera from niniteen families and nineteen subfamilies. A few number of miscellaneous microfossils such as Ostracoda, Holothuroidea and Echinoderm remains were recovered. The total count of foraminiferal defined from this well is four hundred and nineteen (419). The planktic foraminiferal count was two hundred and forty two (242) (57.8 % of the total count) while the benthics foraminiferal count was one hundred and seventy seven (177) (42.2 % of the total count). Among the benthic forms, the calcareous consists of one hundred and forty nine forms (149) (33.4 % of the total benthic count) while the agglutinating benthic forms were thirty seven (37) (8.8 % of the total benthic count). One (1) planktic (Chiloguembelinacubensis) and three (3) benthic (Eponidesberthelotianus, Hanzawaiastratonii and Nonionellaauris) informal foraminiferal zones were established in the well. The age of the AE-1 well sediments has been interpreted to belong to Early Oligocene - Early Miocene in comparism with foraminiferal markers species whose stratigraphic ranges are well established in the Niger Delta and globally. This inferred the presence of the Rupelian - Burdigalian sediments in the Niger Delta.
Keywords: Foraminiferal, Biozone, Age, Rupelian, Burdigalian
Psycho-sociocultural Analysis of Attitude towards Littering in a Nigerian Urban City
This study examined the influence of altruism, environmental self-efficacy, locus of control, self-concept, age, gender, and level of education as predictors of attitude towards littering among residents of some selected communities in Ibadan metropolis. An ex-post cross-sectional research design was adopted for this study. Using a multi-stage sampling technique, one thousand, three hundred and sixty participants participated in the study. Their ages ranged from 18 to 65 years. Data collection was through a battery of measures combined into a single questionnaire. Pearson product-moment correlation, hierarchical multiple regression, and One-Way ANOVA statistical techniques were tools of testing hypotheses. Findings indicated that a combination of altruism, environmental self-efficacy, locus of control, self-concept, age, and gender explained 57% of the variance in attitude towards littering. The relative contributions reveal that altruism (beta = -.23, p < .01), environmental selfefficacy (beta = -.18, p < .01); locus of control (beta =.34, p < .01), and self-concept (beta = -.51, p < .01) contribute significantly to attitude towards littering. Also, level of educational attainment has significant effect on attitude towards littering. These findings provide link between psychological factors and attitude towards littering, and suggest reasons for ineffectiveness of previous anti-littering campaigns among residents of Ibadan. Thus, the psychological variables in this study have implications for interventions on littering attitude.Key words: Attitude, littering, psychosociocultural, urban city, Nigeri
The investigation of the effect of scheduling rules on FMS performance
The application of Flexible Manufacturing Systems (FMSs) has an effect in competitiveness, not only
of individual companies but of those countries whose manufactured exports play a significant part in
their economy (Hartley, 1984). However, the increasing use of FM Ss to effectively provide customers
with diversified products has created a significant set of operational challenges for managers
(Mahmoodi et al., 1999). In more recent years therefore, there has been a concentration of effort on
FMS scheduling without which the benefits of an FMS cannot be realized.
The objective of the reported research is to investigate and extend the contribution which can be made
to the FMS scheduling problem through the implementation of computer-based experiments that
consider real-time situations. [Continues.
Perception of in-school adolescents about adolescentfriendly characteristics of healthcare services received in Ibadan Metropolis, Nigeria
Introduction: Adolescence was previously assumed to be a diseases free stage of life. It is however now known that adolescents are not only involved in risky health behaviours but they also have their own share of health problems that other age groups face. The adolescent-friendly model helps to create adolescent-responsive health systems, Nigeria currently has no country-specific report on the adolescentfriendly characteristics of the health services rendered to her adolescents. This study identified various health problems for which in-school adolescents in Ibadan North-East Local Government Area sought healthcare and determined their perception of received healthcare services with regards to its “adolescent-friendliness”.Methods: This was a school-based cross-sectional study that utilized quantitative method of data collection. A multi-stage systematic random sampling technique was employed to select 500 students for school survey. Self-administered, semistructured questionnaire was used to collect data. Descriptive statistics and Chisquare test at α=0.05 were used for data analysis.Results: Perceived malaria (52.4%), acne (36.2%), menstrual pain (17.0%) and depression (3.0%) were the common health problems adolescents sought health care for. Majority of the adolescents perceived the health services received as being adolescent-friendly. These health services were perceived to be accessible by (87%), acceptable by (93.2%), appropriate by (81.4%), effective by (91.4%), and equitable by (82.2%) of the respondents. Adolescents who sought mental care perceived least adolescent-friendliness of received healthcare services.Conclusion: Adolescents in Ibadan currently view received health services as adolescent-friendly. However, the management of mental health problems in adolescents should incorporate adolescent friendly elements entrenched at every level of the health system.
Keywords: In-school adolescents, Adolescent health problems, Adolescent-friendly health services, Health seeking behaviour,Nigeria
Internal Model Loss Minimization Control of Permanent Magnet Synchronous Machine
Electric drives are very useful in propelling the wheels of hybrid electric vehicles (HEVs). They also play a central function in the electric power steering (EPS). This paper describes studies carried out on the efficiency optimization of an interior permanent magnet synchronous machine (IPMSM) for application in the EPS. An analytic loss- minimization algorithm for an IPMSM was derived and the optimization problem took into consideration copper, iron and stray losses. The proposed loss minimization algorithm is simple and cost effective to implement. From the simulations carried out, significant efficiency gains are possible with this model. The internal model control (IMC) method was employed to achieve current and speed control with acceptable sensitivity to machine parameters
Seasonal evaluation of groundwater quality around Igando dumpsites in Lagos metropolis using correlation and regression analysis.
Correlation and Multiple linear regression analysis was used to establish the degree of relationship and variability of groundwater quality parameters around Solous 1 and 2 Dumpsites, in Igando, Lagos, for the wet and the dry seasons. The correlation between TDS and other hydrochemical parameters which constituted the independent variables were positive, with significantly high positive correlation exhibited between TDS and EC for the wet season. For the dry season, the correlation between TDS and other groundwater quality parameters (EC, NO3- and Cl- ) was positive, while its correlation with Zn2+ and Fe2+ was negative. The results of the multiple linear regressions for the wet and the dry seasons indicate that the model accounts for 96.8 percent and 93.9 percent, respectively of the variance of TDS concentration of groundwater around the dumpsites.@JASE
Analysis Of Rainfall Distribution In Owerri And Enugu, Nigeria Using Precipitation Concentration Index
The precipitation concentration index (PCI) of Owerri and Enugu for 1974 to 2011 was computed to characterise the rainfall distribution for both locations. The PCI was estimated on an annual and seasonal scale. The seasonal estimation was based on the categorisation of the seasons in eastern Nigeria into long wet season, short wet season, short dry season and dry season. The results of the PCI computed for Owerri showed that 87% of the years for which annual PCI was computed fell within the moderate concentration category range, while for Enugu 71% of the years fell within the moderate concentration category. For the long wet season for the study period, 74% and 66% of the years fell within the uniform precipitation concentration category at Owerri and Enugu, respectively, while 13% of the years at Owerri, and 16% of the years at Enugu fell within the moderate precipitation category. The varying degrees of precipitation concentration as indicated by the study implies that effective management of water resources and agriculture, and the control of erosion in the study locations might be more difficult to achieve under the prevailing climatic conditions.Key Words: Precipitation Concentration Index; Owerri, Enugu, Rainfall; Variabilit
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