CURRENT ISSUE   Vol. 6 No. 1 – March 2022


Spectral Noise Estimation: A Python 3 Implementation of the Minimum Statistics Estimation
Bello N. and Ogbeide K. O.
https://doi.org/10.36263/nijest.2022.01.0300


ABSTRACT
Noise estimation has been used majorly in imaging processing and voice speech recognition applications. Therefore, researchers have found optimal solutions to non-stationary noise estimation. Particularly, there is a proposed method that estimates spectral noise in a noisy speech signal which is based on two observations; speech pauses and approximation of power spectral densities of the noisy signal to the true noise during speech pauses. Though from recent studies, the observations obtained cannot be inferred for other types of signals especially RF signals and have not been tested on signals in the frequency domain, this paper bridges that gap of research and presents the results, analysis, and conclusion on the findings concerning the noise estimation with RF signals using an extension of the proposed method in the frequency domain. It presents a detailed methodology of implementation of the minimum statistics method for noise estimation in python 3 code which was tested with RF signals and thus met the requirement of dynamic thresholding with spectrum occupancy measurement.

Keywords: Spectral estimation, Minimum statistics, Smoothing, Noise estimation, RF signals, Dynamic thresholding

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Design of a Robust Orthogonal Frequency Division Multiplexing (OFDM) Transceiver for a Cognitive Radio Testbed
Bello N. and Edeko F. O.
https://doi.org/10.36263/nijest.2022.01.0301


ABSTRACT
Primarily, a Cognitive Radio (CR) resolves the problem of spectrum scarcity and underutilization. However, it should also attain a good throughput and Quality of Service (QoS) as its objectives. These requirements are solely dependent on the modulation used. Though single carrier modulations such as Gaussian Minimum Shift Keying (GMSK) are highly spectral efficient, they are not robust to frequency selective fading. An implementation of multicarrier modulation supports high spectral efficiency and resistance to multipath fading. Therefore, in this paper, there is a comprehensive how-to-guide of the design of Orthogonal Frequency Division Multiplexing (OFDM) in cognitive radio using GNU Radio (GR) 3.8 that interfaces with Universal Software Radio Peripheral (USRP) B210s for video transmission. The implementation achieved allows for the choice of any modulation schemes out of four commonly used ones for communication of the payloads thus offering dynamism for use in a cognitive radio system. The effective implementation of the proposed methods in this paper is verified by the successful transmission and reception of a 4 minute 37 seconds MP4 video across the different choices of modulation schemes. It was observed that the error performance of the payloads degraded with higher constellation points however, the throughput was increased. Hence, the trade-off between error probability and throughput in the cognitive radio is based on the radio-scene metrics about the signal-to-noise ratio (SNR) of the available channels.

Keywords: OFDM, GNU Radio, SDR, USRP, VLC, wireless streaming, cognitive radio, GStreamer

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Efficacy of the Methanolic and Aqueous Extracts of Carica Papaya and Azadirachta Indica against Wood Termite (Odontotermes Badius) in Uyo, Akwa Ibom State, Nigeria
Akpan A. U., Ehisianya C. N., Ukpai O. M., Johnny I. I., Oboho D. E., Sam M. E. and Usanga E. E.
https://doi.org/10.36263/nijest.2022.01.0306


ABSTRACT
Evaluation of the efficacy of methanolic and aqueous extracts of Carica papaya and Azadirachta indica against the wood termite (Odontotermes badius) was carried out in the Botany garden, University of Uyo main campus, Akwa Ibom State. The phytochemical properties of the extracts were carried out in the Department of Pharmacognosy and Natural Medicine, Faculty of Pharmacy, University of Uyo, Akwa Ibom State, using the standard procedures. The untreated wood (Ceiba pentandra) was cut into 60 pieces of equal sizes of 11cmx8cm. 40ml and 80ml concentrations (Using 100ml unit syringe) of each of the extracts of the leave and stem parts of C. papaya and A. indica were applied on the woods using soft-faced brush, the control treated with water. The treated woods well marked using marker together with the control were inserted horizontally into the termitarium and were monitored for 24, 48, 72 and 96 hours. The data collected were analyzed using two ways Analysis of Variance (ANOVA), and their means separated using p < 0.05 probability. The phytochemical screening result of aqueous and methanolic extract of C. papaya and A. indica indicates the presence of flavonoids, saponins, tannins, terpernoids, phenols, cardiac glycosides, alkaloids and anthraquinine. In conclusion, from the results showed that the methanolic plant extract of C. papaya and A. indica leaves and stem offered greater effectiveness for wood protection against termite (O. badius) compared to aqueous extracts of the plants.

Keywords: Extracts, Aqueous, Carica papaya, Azadirachta indica, Odontotermes badius

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Occurrence and Health Risk of Heavy Metals and Microorganisms in Wastewater Collected from selected Eateries in Lekki, Lagos, Nigeria
Tajudeen Y., Abdulganiyu Y., Alkali M., Ukpere M., Ayodeji S. O., Ahmadu A. I. and Faluyi B. A.
https://doi.org/10.36263/nijest.2022.01.0316


ABSTRACT
The number of eateries is growing around the world because they provide jobs and food to urban people who do not have time to cook. However, there are concerns that eatery wastewater may contain hazardous compounds and microorganisms. In view of the above, this study determined the chemical characteristics, heavy metal concentrations, and microbiological loads of wastewater collected from three eateries in Lekki, Lagos, Nigeria. The human exposure to heavy metals via oral and dermal contact, as well as the hazard quotient of daily exposure to these heavy metals, was also calculated. The chemical characterization revealed that nitrate, ammonia, and phosphate levels in all of the wastewater samples were above the limits of the Federal Environmental Protection Agency, while sulphate levels were normal. Copper, lead, cadmium, nickel, and chromium levels were within the permissible levels, but zinc was above the limits in the three eateries. The average daily oral and dermal exposure to heavy metals was normal, while the hazard quotient of daily dermal exposure to zinc and chromium in the three eateries was abnormal (> 1). In all of the eateries, bacterial and fungal levels were above permitted limits, but no coliforms were found. The results imply that the wastewater from the three eateries are hazardous and could pose environmental and health hazards. It is recommended that eatery owners treat wastewater before releasing it into the environment.

Keywords: Ammonia, Average daily Ingestions, Bacteria, Eateries, Lead, Wastewater

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Factors Influencing Users’ Preference for Green Features in Residential Buildings: Experience from Ibadan Municipality, Nigeria
Adejumo A. O., Oyewole M. O., Araloyin F. M. and Adebara T. M.
https://doi.org/10.36263/nijest.2022.01.0328


ABSTRACT
The study examines factors influencing users’ preference for green features in residential buildings of Ibadan municipality, Nigeria. The study population comprised residents in the five local government area of Ibadan municipality. Using systematic sampling, 267 households were selected for questionnaire survey. Questionnaire was administered on the household heads in the study area. Data obtained were analyzed using percentages and relative importance index (RII). The result showed that ‘knowledge regarding benefits of green building’ with RII of 4.50 ranked first among factors that influence preference for green features. Other factors with high degree of influence on users’ preference for green features in residential building in the study area are the ‘level of education’ and ‘level of income’ with RII of 4.48 and 4.46 respectively. The knowledge of the outcome of this study is expected to benefit real estate investors and other stakeholders in property market and promote policy regarding green building development and investment in the country and other emerging nations of the world.

Keywords: Green buildings, Green features, Environmental degradation, Climate change, Global warming, Ibadan

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Sensitivity Analysis of Suspected External Driving Factors Contributing to Land Use Land Cover Dynamics in Jos Plateau State, Nigeria
Zitta N., Musa A. A. and Muhammed I.
https://doi.org/10.36263/nijest.2022.01.0297


ABSTRACT
Land use land cover change (LULCC) processes are directly or indirectly product of underlying causative factors playing out on the landscape. This study examines the contributing factors responsible for LULCC in Jos Plateau state using two different methods. The Analytical hierarchical process (AHP) and Binary models were used to prepare sixteen (16) suspected external driving factors (EDFs). Euclidean distance analysis was carried out on the proximity EDFs as well as reclassification based on AHP scale 1 – 9 and binary mode as 1 & 0. Saaty’s pairwise comparison matrix was employed to generate the weights for all the EDFs with a consistency index (CI) of 0.17was achieved. Suitability images were generated by multiplying each EDF with the corresponding weight. The fuzzy set membership standardization was carried out on the AHP image through sigmoidal function type with monotonically increasing membership function.The multiple regression technique was used to measure the sensitivity of each driver against the change period (1986 – 2019). The result shows that five (5) EDFs where consistent in both approaches (AHP & Binary). They are: distance to conflict areas, distance to major roads, LULC, distance to settlements and distance to river/ channels. It is therefore, appropriate to examine EDFs to know how each driver is contributing to the changing landscape in the study area. The findings has revealed the main factors driving LULC changes in the study area and has provided a reference frame for assisting in the development of sustainable land management and ecological protection policy making and decisions.

Keywords: Analytical, Binary, Regression, Factors, Sensitivity

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A Critique of the Capital Market Content in Nigerian Real Estate Education
Onwuanyi N. and Adekanmi A.
https://doi.org/10.36263/nijest.2022.01.0327


ABSTRACT
The Nigerian Stock Exchange (NSE) is taking on an increasing relevance for the Nigerian estate surveyor and valuer as it grows in capitalization and sophistication. This can be seen in the NSE’s second-largest status in sub-Saharan Africa, the introduction of property securitization and the listing of property companies. Since these changes have implications for the valuer’s professional practice, they necessitate an evaluation of the real estate training curriculum. The capital market content of real estate education in Nigeria is examined in this paper by assessing the knowledge held by recent graduates of estate management. A questionnaire founded on a checklist of pertinent issues which realistically depict a working knowledge of Nigeria’s much improved stock market was used to collect data. This was analyzed by simple descriptive tools to provide a basis for evaluation. The results point to a scanty curriculum. In addition, there is a low awareness of the administrative and economic functions of the NSE. Furthermore, respondents have a poor understanding of core issues in equity investment analysis. Again, there is an inadequate grasp of the relationship between the two investment alternatives, although a majority rightly credit property as a better option. Lastly, respondents mainly do not consider an understanding of the market as relevant to their professional function in a modern economy. The study concludes that the demonstrated knowledge of respondents suggests that the curriculum does not have adequate content on the capital market. It is, therefore, recommended that the capital market content of the estate management course be enriched with more depth and detail which adequately reflect the increasing significance of the market to the valuer’s practice and his true role as an investment adviser in an increasingly financially interconnected world.

Keywords: Capital market, Estate management, Nigeria, Property market, Real estate

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Soil Nutrient Dynamics and Potentially Toxic Elements of Sand Mining Impacted Agrarian Land in Obowo, Southeastern Nigeria
Ubuoh E. A., Uzonu I. U., Uchendu U. I. and Ndukauba F. C.
https://doi.org/10.36263/nijest.2022.01.0329


ABSTRACT
The study assessed the effect of inland sand mining activities on the physicochemical properties and potentially toxic elements in soils in Umuna, Obowo LGA, Imo State, and Southeastern Nigeria. Triplicate soil samples were collected from soil depths ranging from 0-15, 15-30 cm) in eight traverse points and control. Points were designated soil sampling point (SSP) ranging between SSP1-SSP8 and control sample point (CSP1). The results of the particle distribution were in order of Sand ≥ Clay ≥ Silt, with Textural class ranging from sandy loams to loamy sandy. Chemical tracers: Soil pH ranged from 4.8 – 5.7 signifying moderate to strong acidity. The available P, Total N., SOC,SOM and BS ≤ control and Maximum Tolerable limits and FAO /World Reference Base. Effective cation exchange capacity (ECEC) (cmol/kg) (Ca2+, Mg2+, K+ and Na+), with mean Ca2+ 3.02, Mg2+, 0.64, K+ 0.09, Na+ 0.10 ≤ control respectively. Exchangeable acidity recorded 1.04 ≥ control, and CEC: 6.22 ≤ the control. Based on the ratings of soil nutrients for agricultural soil, the soil nutrients status of the sand mined sites ranged from very low to low status for total N(0.02 -0.04), avail. P (6.55-9.96), exchangeable K, (0.07-0.14), exchangeable Ca (2.25-3.55), and exchangeable Mg (0.25-0.85). Copper the mean value of 15.21, Lead: 12.20 and Cadmium (1.80) ≥ control (zero) above the FAO/WHO permissible levels respectively. Chromium (2.65) ≤ the FAO/WHO, limit. The potentially toxic heavy metals are in order of abundance in sand –mined soil: Cu ≥ Pb ≥ Cr ≥ Cd, with copper dominating the soil. The conservation of the area requires ecological restoration and regeneration of degraded mining site and the prohibition of mining activities as well as strict local control and enforcement of mining laws.

Keywords: Mining, Heavy metal, Soil degradation, Land restoration

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Warfare Disaster Ecology: Connecting Warfare Ecology and Disaster Risk Management Curricula
Agheyisi J. E.
https://doi.org/10.36263/nijest.2022.01.0333


ABSTRACT
This paper examines the topics of ecological change induced by war and the interactions between environment and warfare which though have received major attention from warfare ecology but not yet conceptualized as an area of enquiry in disaster risk management studies. This paper therefore compares warfare ecology and disaster risk management in order to bring out some of their more general characteristics with the purpose of greater conversation and collaboration across the two fields. The aim is to develop a new curriculum of ‘warfare disaster ecology’ (WDE) in disaster risk management studies. The objective is to better identify their potential linkages and synergies. This paper is based on desktop review of extant literature on disaster ecology. Criteria for inclusion of the reviewed articles were based on (1) the article’s relevance to the proposed curriculum, and (2) the article’s applicability to disaster risk management. The paper provides justifications for the development and domiciliation of warfare disaster ecology in disaster risk management studies, pointing to research themes and scales at which warfare disaster ecology can be studied. It suggests greater opportunities for interdisciplinary approach and closer connections between warfare ecology and disaster risk management, thereby expanding the curriculum and areas of specialization for graduate students in disaster risk management studies. It proposes a research direction for academics and policy implications of WDE to guide military policy-making and planning, peace-building and conflict resolution, and environmental protection for all the concerned bodies.

Keywords: Armed conflict, Coupled system, Curriculum, Environment, Military

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Vulnerability of Coastal Communities to Sea Level Rise in Brass Local Government Area, Nigeria
Efere Z. S. and Ohwo O.
https://doi.org/10.36263/nijest.2022.01.0329


ABSTRACT
Coastal communities are continuously under threat of survival due to sea level rise, which has increased their vulnerability to inundation resulting to loss of livelihood, property and land area. Hence, this study investigated the vulnerability of the communities in the Brass coast to the impacts of sea level rise. Three communities (Twon-Brass, Okpoama and Diema) located within 0 – 1.2km from the shoreline, and where economic activities are prominent were purposively selected for the study. To assess the level of vulnerability of these communities to sea level rise, the coastal vulnerability index method comprising of six variables (topography, geomorphology, relative sea level rise rate, annual shoreline erosion rate, proximity to coast and population growth rate) were adopted. Landsat imageries at 10years interval for the period 1999 to 2019 were acquired to analyze the Brass shoreline dynamics. The results revealed that for a period of 20 years (1999-2019), the Brass coast has experienced a net land loss of 364.0km2 and a projected land loss of 910km2 by 2050, based on the current scenario. The study further revealed that Twon-Brass and Okpoama communities have high risk of inundation due to sea level rise with a calculated coastal vulnerability index values of 23.1 and 25.3, respectively; while Diema community had moderate risk of being inundated with a coastal vulnerability index value of 21.9. The study recommends the development of an integrated mitigation and adaptation strategy that would increase the resilience of the coastal communities to withstand the threat of sea level rise.

Keywords: Coastal communities, Brass, sea level rise, shoreline change, vulnerability index

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Groundwater Storage Analysis Using Deterministic Model Approach for Water Resources Management of Zamfara part of Sokoto-Rima Basin, Nigeria
Shuaibu A.M. Garba M.L. and Abubakar I.Y.
https://doi.org/10.36263/nijest.2022.01.0337


ABSTRACT
The study area is entirely located within the Sokoto-Rima hydrological basin of Northwest, Nigeria. Groundwater is widely used for drinking, domestic and agricultural purposes in Zamfara water catchment. The mismanagement of groundwater resources could cause negative effects including depletion of aquifer storage and groundwater level decline. To assure sustainability of the available resources, determination of groundwater budget is necessary. Deterministic model approach was used, which required three quantities (Available water quantity, Abstractible and Storable water volume). In this study meteorological water budget (MWB), water level fluctuation (WTF), and groundwater budget based on geological framework (GBBDF) were used to estimate water budget. Groundwater recharge and abstraction rate were calculated from 280 borehole data across the water catchment area. The average groundwater budget of the study area was calculated as 111,693,470 m3/year with the MWB method and it was calculated as 111,342,057.3m3/year and 73,463,099 m3/year with the WTF and (GBBDF) methods respectively. The groundwater abstraction for domestic/agricultural uses was calculated to be higher to that of aquifer recharge. Thus prudent measure has to be adopted for adequate water use per head as population increase and demographic change will exacerbate more stress on the availability of this precious resources aside the climate change impact. The implication is that further proliferation of borehole wells will deplete the entire aquifer and subject it to be devoid of manageable storage capacity, particularly in the crystalline aquiferous units. It is clear that, if conceptual hydrogeological modelling of the catchment is well known and reliable data are obtained, the MWB method gives accurate results in the basins. However, comparison of multiple methods is valuable for determining the plausible budget amount and for highlighting the uncertainty of the estimate.

Keywords: Zamfara Hydrogeological Catchment, Groundwater budget, Aquifer Recharge/Abstraction, Sustainable Management

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Tidal Constants Derivation for Imo River
Udoh I. B. and Ekpa A. U.
https://doi.org/10.36263/nijest.2022.01.0335


ABSTRACT
Tides play critical role in coastal processes, marine operations and navigation. Determination of tidal characteristics and prediction of water levels require knowledge of tide harmonic constants (amplitudes and phase lags) of all relevant tidal constituents. 37 days hourly water level observation was taken at established tide gauge station along Imo River and analysis of observed data using harmonic method implemented with T_Tide. 35 tidal constituents were generated and used for water level prediction. Tidal constants of four principal tidal constituents (K1, O1, M2 and S2) were used to compute tidal form factor and water level datum for the river. The analyses revealed that M2 constituent was the most dominant tidal constituent with amplitude of 0.7375. Computed form factor (0.2076) revealed Imo River to have a semidiurnal tidal regime which is the characteristics of Nigerian coastal waters. The river has a tidal range of 2.231m and mean water level of 1.660m. Comparison of predicted and observed tide gave root mean square error of 0.0177 and correlation coefficient of 0.9943. Results obtained from the study indicated that derived tidal constants are reliable for prediction of Imo River water levels and tide.

Keywords: Imo River, Water level, Harmonic analysis, T_tide, Tidal constant

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Environmental Sanitation Practices: Residents’ Involvement in Ilesa, Nigeria
Olatunji S., Yoade A. and Olanrewaju S.
https://doi.org/10.36263/nijest.2022.01.0213


ABSTRACT
This study examined residents’ involvement in environmental sanitation in Ilesa, Nigeria. Using multistage sampling, six political wards were selected: three from the high-density area, two from the medium-density area, and one from the low-density area. In all 300 copies of the questionnaire were administered. Data obtained were analysed using percentages and the Pearson correlation. This was with a view to suggesting policy response capable of enhancing healthy environment in the city and others with similar background. Information on the kind of toilet available revealed that 50.9% used flush toilet, 30.1% used pit latrine while 19.0% had no toilet. Likewise, there is paucity of public toilet in the city as 5.0% of the residents claimed availability of public toilet in their neighbourhood while 95.0% said public toilet was not available in their neighbourhood. Furthermore, the agencies responsible for environmental management were found to be wanting in some key functions with implications for healthy living in the area. Based on the findings, policy recommendations are proffered to enhance environmental friendliness in the city.

Keywords: Environmental, Sanitation, Involvement, Hygiene, Health

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Ecological Effects and Vulnerability Assessment of Flooding in Udu Local Government Area, Delta State, Nigeria
Ndakara O. E. and Atuma I. M.
https://doi.org/10.36263/nijest.2022.01.0330


ABSTRACT
This study is based on the ecological effects and vulnerability assessment of flooding within Udu Local Government in the Delta State region. This research adopted the survey design. Five (5) flood vulnerable communities which represent the major subdivisions in Udu were investigated. Stratified random technique of sampling was used to divide the communities into quarters for effectiveness in data collection, while simple random technique was adopted in the collection of data. Data collection was on the communities covered by flood, causative factors of flooding, and the resultant effects on human inhabitants, environment, and the prevailing economic activities within the region. Data collection was through direct field survey and the use of questionnaires. The instrument’s level of reliability was achieved at 0.89 using the test-retest method; while instrument validity was determined by experts’ judgements. Data collected were analysed using the descriptive, ANOVA and regression statistics. Results showed that the communities investigated are vulnerable to flooding; significant difference was not found in the observed causative factors of flooding among the vulnerable communities; the effect of flooding is high within the study area; the differences in the effects of flooding within the different flood vulnerable communities in the study area is not significant at 0.05 level of confidence; and no significant relationship exists between the causative factors and the effects of flooding at 0.05 level of confidence. Therefore, good settlement planning, construct of drainage, and selective terrain cultivation are recommended.

Keywords: Ecosystem, environmental hazard, flood, interaction, vulnerability

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Hydraulic and Water Quality Modelling of Water Distribution Networks Using EPANET Software
Junaid C. T. and Izinyon O. C.
https://doi.org/10.36263/nijest.2022.01.0342


ABSTRACT
In this study, hydraulic analysis of two water distribution networks was carried out using EPANET 2.0 software developed by the US Environmental Protection Agency. The study networks are: a hypothetical 65-pipe water distribution network that had been solved by the Linear Theory method; and an existing water distribution network serving the University of Benin Ekehuan campus, for which hydraulic analysis and study for the system improvement had been previously carried out using WaterCAD software. This present study was therefore undertaken to investigate EPANET’s capability in executing hydraulic analysis and deploying it for water quality simulation studies of the campus’ water distribution system, which was not part of the scope of the previous study. The hydraulic analysis results showed that the average of deviations from solved values for total head, pressure head, and flow are 4.23%, 7.69%, and 7.15% respectively, which falls within an acceptable range. Results from the water quality analysis study in which water age and optimum residual chlorine dosage required were used as surrogates for water quality indicate that the existing water distribution network of the campus has a water age and optimum residual chlorine of 1.68 hours and 0.220mg/L respectively, while same for the proposed improved water distribution network of the campus are 5.56 hours and 0.255mg/L respectively. Expectedly, the water age and optimum residual chlorine of the improved network are higher than those of the existing network, as the pipe sizes and storage capacity in the improved network are larger to serve the increased future population of the ultimate design period. Even at that, the obtained values are within acceptable limits prescribed by the Nigerian Standard for Drinking Water Quality (NSDWQ) guidelines. Hence, it is concluded that EPANET and WaterCAD are efficient piped-water network simulation software and can be relied on for use in developing countries.

Keywords: Hydraulic analysis, Water quality modelling, Water age, Residual chlorine, Pipe network design, Pressure head, Flow

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