bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of ferroresonance in underground distribution network for 15MVA, 33/11 kV injection substation
Authors: Koledowo S.O. , Ashigwuike E.C. , Bawa A. 
Published: June 2020

This provides an overview of ferroresonance phenomena, modeling aspects and practical experience in recognizing and mitigating the effect of ferroresonance in the power network. In particular, we will present symptoms of ferroresonance. In this study, ferroresonance phenomenon are investigated under the modelling of the underground cable of 15 MVA, 33/11/0.415 kV with four feeders supply over 31 distribution transformers of Garki 1 service unit, Abuja, conducted using MATLAB/SIMSCAPE software package. The network is subjected to switching resulting in the formation of a series LC combination prone to ferroresonance. The waveforms and total harmonic distortion charts obtained are observed, analyzed and then used to design Harmonic filters which have been implemented to mitigate ferroresonance in the network. The simulated ferroresonance phenomenon was suppressed using Shunt Active Harmonic Filter connected in parallel to the network. A reduced harmonic content and dampened event when compared to a non-filtered event was observed. Application of Shunt Active Harmonic filter reduces ferroresonance effect by 67.743%.
Keywords: Ferroresonance, Transformer, MATLAB/Simscape, Harmonic Distortion, Power system Modelling, Saturable inductor, Capacitance
Model prediction and climatology of aerosol optical depth (τ550) and angstrom exponent (α470-660) over three aerosol robotic network stations in Sub-Saharan Africa using moderate resolution imaging spectroradiometer data
Authors: Sharafa S.B. , Aliyu R. , Ibrahim B.B. , Tijjani B.I. , Darma T.H. , Gana U.M. , Ayedun F. , Sulu H.T. 
Published: June 2020

The spatial and temporal variations of aerosol optical depth at 550 nm (τ550) and Angstrom exponent derived from 470 and 660 nm (α470-660) over Nairobi (NAI), Skukuza (SKU) and Ilorin (ILO) Aerosol Robotic Network (AERONET) stations in sub-Saharan Africa, as recorded by Moderate Resolution Imaging Spectroradiometer (MODIS) satellites for fifteen years (2000-2015), were examined in relation to their climatologies and prediction. The MODIS measurements of τ550 and α470-660 from aqua (MYD04) and terra (MOD04) satellites were used in this study. Retrievals of τ550 for both satellites were validated with AERONET τ550 for the same period. The validation results showed that they compare favourably over the three stations, but MOD04 performed better than MYD04 data in NAI and ILO for τ550. This shows that the τ550 of NAI and ILO are best captured using the MOD04 data while that of SKU is best with MYD04. It was also discovered that MODIS underestimated AERONET τ550 data over NAI and SKU. The most polluted station is ILO while the least polluted one is NAI. Similarly, the station with the highest concentration of absorbing aerosols is NAI and the least was observed in ILO. The aerosol climatology shows that the most polluted months in NAI, SKU and ILO are October, June and March respectively. On the other hand, February, November and March has the highest amount of scattering aerosols in the atmosphere for NAI, SKU and ILO respectively. The highest amount of absorbing aerosols was found, respectively, in the months of June, June and August. The generated time series (TS) models are all good, though a general underestimation of the parameters by the models was also observed.
Keywords: Aerosol optical depth, Angstrom exponent, MODIS, Time series, sub-Saharan Africa
Estimation and comparison of reference evapotranspiration within Kaduna Central District, Nigeria, using four different methods
Authors: Onwuegbunam N. E. , Onwuegbunam D.O. , Dare A. 
Published: June 2020

The reference evapotranspiration (ETo) within Kaduna Central District, Nigeria was estimated from a 30-year climatological data using four different methods namely, Penman-Monteith (PM), Blaney Criddle (BC), Hargreaves (HGRV) and Piche evaporimeter (PiEv) (atmometer) methods. The study shows that the highest ETo values obtained from PM, BC and PiEv were 6.43 mm/day, 7.58 mm/day and 8.63 mm/day, respectively, and these occurred in February, except for HGRV which estimated its highest ETo (3.73 mm/day) in March. The lowest ETo values were obtained in August for all the methods. By means of the confidence index (c), agreement or concordance index (d) and correlation coefficients (r) statistics the BC, HGRV and PiEv ETo values were correlated with that of PM, as the standard. Results showed that BC, HGRV and PiEv gave c-values of 0.88, 0.48 and 0.67, respectively. Hence, BC-PM, HGRV-PM and PiEv-PM correlations were adjudged as excellent, bad and good, respectively, on the basis of criteria for interpretation of the performance of methods of ETo estimations. Blaney-Criddle reference evapotranspiration method gave the best estimate in comparison to the Penman-Monteith standard in the study area. Hence, the Blaney-Criddle ETo can be calibrated with the Penman-Monteith ETo and used effectively within the Kaduna Central District conditions for irrigation water management decisions.
Keywords: Estimation and comparison, Reference evapotranspiration, Methods, Kaduna Central District, Nigeria.
A taxonomy of building collapse causes in Lagos State Nigeria
Authors: Imafidon M.O. , Ogbu C.P. 
Published: June 2020

This Lagos-based study provides an unsupervised grouping of the causes of building collapse in Lagos State Nigeria using purposively obtained data from construction professionals (n=34) in the state. Hierarchical cluster analysis technique and mean scores were used for the analyses. Findings show that the causes of building collapse in Lagos State can be statistically grouped into design and construction-related, policy-related and quality-related causes. The most important causes of building collapse under each of these groups are respectively: poor maintenance culture, change of use of building and use of substandard materials in construction. Government needs to strengthen efforts at monitoring both the design and construction of buildings, starting with fine-tuning building related policies. A holistic approach should be adopted in addressing building material counterfeiting and circulation of substandard construction materials in the study area.
Keywords: Building Approval, Building Collapse, Building Failure, Cluster Analysis, Lagos State.
Predicting the split tensile strength of Saw Dust Ash - Fine aggregate concrete
Authors: Oba K.M. , Ugwu O.O. , Okafor F.O. 
Published: June 2020

The industrial waste, Saw Dust Ash (SDA), has played a key role in concrete mix research. It has served as an alternative or complementary material to some of the traditional materials of concrete. In this study, SDA was used to replace 5% of the fine aggregate (sand), as the other three ingredients, cement, granite, and water remained constant. Scheffe’s simplex lattice was used for five mix ratios in a {5,2} component mix, which resulted in additional ten mix ratios. Additional fifteen mix ratios were generated for verification and testing. The thirty concrete mix ratios were subjected to laboratory experiments to determine the 28 days Split Tensile Strengths. The results of the first fifteen Split Tensile strengths were used for the calibration of the model constant coefficients using Scheffe’s simplex approach, while those from the second fifteen were used for the model verification. A mathematical regression model was derived from the experimental results, with which the Split Tensile Strengths were predicted. The derived model was subjected to a two-tailed t-test with 5% significance, which ascertained the model to be adequate with an R2 value of 0.8099. The study revealed that SDA can replace 5% of fine aggregate and promote sustainability, without compromising the 28 days Split Tensile Strength.
Keywords: Saw Dust Ash, Scheffe’s simplex lattice, Split Tensile Strength of concrete.
Digestible lysine effects on gene expression by Japanese quails in the pre-laying phase
Authors: Santana T.P. , Gasparino E , Bastos M.S. , Lima A.S. , Pinto A.P.G. , Oliveira Junior G.M. , Brito C.O. , Barbosa L.T. , Del Vesco A.P. 
Published: June 2020

This study aimed to determine the effects of digestible lysine levels in the diets of Japanese quail (Coturnix coturnix japonica) on performance, blood parameters and the expression of insulin-like growth factor I, and growth hormone receptor (GHR), apolipoprotein A-I (APOA-I), acetyl-CoA-carboxylase (ACC), and fatty acid synthase (FAS) genes. A total of 288 seven-day-old female Japanese quails were randomly assigned to one of three diets that contained 0.8%, 1.10%, or 1.40% digestible lysine. The birds were slaughtered at 42 days old, and relative gene expression was evaluated in the liver by qRT-PCR using the 2-ΔCT method. Lysine supplementation had no effect on weight gain and feed conversion. Abdominal fat was lower in birds supplemented with 0.8% digestible lysine than those supplemented with 1.10% and 1.40%. Increased total cholesterol and triglycerides were elevated in quails that received supplementation of 1.10% digestible lysine compared with the other diets. High density lipoproteins were decreased in birds that received 0.8% digestible lysine. Quails fed with 1.40% digestible lysine had greater expression of GHR and APOA-I than quails fed diets with 0.8 and 1.10% (P <0.05). The greatest expressions of ACC and FAS were observed in the liver of quails fed with 0.8% digestible lysine. The current results suggest that lysine supplementation in the pre-laying phase allows birds to deposit muscle mass to reach the optimal conformation and body fatness that provides an energetic reserve for the productive phase by modulating the expression of genes related to growth and lipid metabolism.
Keywords: Coturnix coturnix japonica, growth, growth hormone, lipid synthesis, lipid metabolism
Effects of Lavender (<i>Lavandula angustifolia</i>) augmentation of alfalfa silages
Authors: Duru A.A. 
Published: June 2020

The aim of this study was to determine the chemical, fermentation, and microbiological properties of alfalfa silages that were augmented with lavender (Lavandula angustifolia) and to appraise their in vitro organic matter digestibility (IVOMD), metabolizable energy (ME), and net energy for lactation (NEL) contents. Lavender flowers were added to alfalfa silages at 0.5, 1.0, 1.5, and 2.0% of the weight of alfalfa. An unaugmented alfalfa silage was also evaluated. After 75 day of ensiling, pH, dry matter, NDF and ADF contents of alfalfa silages had decreased and OMD had increased with the addition of lavender. No significant differences in crude protein, ash, ether extract, lactic acid, acetic acid, propionic acid, lactic acid bacteria number, ME and NEL contents were detected. No butyric acid, Enterobacteriaceae, Listeria spp, sulphide reducing anaerobes, and yeasts were found in the alfalfa silages. Mould content decreased with the addition of lavender. Thus, the addition of lavender flowers to alfalfa silages may improve their quality.
Keywords: essential oil, fermentation, nutritional value, supplement
Effect of controlled breeding on performance of beef cattle in Central Bushveld bioregion
Authors: Grobler S.M. , Scholtz M.M. , Neser F.W.C. , Greyling J.P.C. , Morey L 
Published: June 2020

In most extensive beef production systems in South Africa, calves are weaned at specific dates. This implies that cows that calve late in the season wean younger and lighter calves. In the current study, Bonsmara cows were mated naturally after synchronization over six years (2009 - 2014) in an extensive production system on natural veld in the Central Bushveld bioregion. Within the herd, 50% of cows were synchronized prior to the commencement of the summer breeding season and they were mated naturally for 90 days. The results indicated that calving rate did not differ significantly between cows that were synchronized and non- synchronized. However, there was a significant difference between years in calving rate. Oestrous synchronization prior to natural breeding influenced the average days to conception. The difference in percentage of cows that calved within 293 days of the onset of the breeding season between those that were oestrous synchronized and non-synchronized was 15% in favour of the synchronized cows. Although calves from synchronized cows achieved higher average weaning weights, the cost implications of synchronization offset the benefit of higher calf weights.
Keywords: calving rate, oestrous synchronization, natural breeding
Genetic diversity and differentiation among Korean-Holstein, Hanwoo, and Uganda-Holstein breeds
Authors: Bigirwa G , Kim D , Acai O , Na C , Oh J , Song K 
Published: June 2020

The aim of this research was to assess genetic diversity of Korean-Holstein, Korean Hanwoo, and Ugandan-Holstein dairy cattle. DNA was extracted from either blood or hair of Korean-Holstein (n=74), Korean-Hanwoo (n=75) and Ugandan-Holstein (N=77) using AccuPrep® PCR purification kit. The DNA samples were amplified by multiplex polymerase chain reaction, using GeneTrackTM Hanwoo genotyping kit and assayed using ABI genetic analyser 3130XL. Number of alleles, expected heterozygosity (He), observed heterozygosity (Ho), and the polymorphism information content (PIC) were estimated from 10 microsatellite loci in the three breeds. In addition, F-statistics for each of the 10 microsatellites in the three cattle breeds were estimated using fstat version 2.9.3.2 computer program. GENETIX (v.4.02) was used to perform factorial correspondence analysis (FCA) from the allele frequencies and multi-locus clustering was done using STRUCTURE analyses. A total of 124 alleles were detected. The number of alleles per locus varied from eight (TGLA126) to 22 (TGLA122), with an overall mean of 12.2. Expected heterozygosity ranged from 0.617 (SPS115) to 0.854 (TGLA53) and averaged 0.761. Observed heterozygosity ranged from 0.6 (SPS115) to 0.859 (TGLA53); and averaged 0.761. The mean PIC was 0.723; and means of the F-statistics FIT, FST and FIS were 0.077, 0.076 and 0.001 respectively. Although FCA revealed clear differentiation of Uganda-Holstein, Korean-Holstein, and Hanwoo, clustering assignments showed genetic admixture between Ugandan dairy cattle (Uganda-Holstein) and Hanwoo. In conclusion, the allelic variation present at the 10 loci was sufficient to categorize these cattle into distinct breed groups.
Keywords: dairy cattle, genetic differentiation, F-statistics, heterozygosity, microsatellite
Performance of sheep grazing <i>Panicum maximum</i> cv. Massai and supplemented with protein sources during the dry season
Authors: Fernandes L.S. , Difante G.S. , Neto J.V. Emerenciano , Araújo I.M.M. , Veras E.L.L. , Costa M.G. 
Published: June 2020

The low quality of tropical grasses in the dry season justifies the use of dietary supplements to meet the nutritional needs of sheep. The objective of this study was to evaluate the effect of supplementation with high-protein feed on mutton sheep performance and yield in Massai grass pastures during the dry season. The treatments corresponded to four supplements, namely Leucaena leucocephala leaf hay, Gliricidia sepium leaf hay, soybean meal, and a treatment that received only multiple mixture (protein salt) ad libitum. The pasture was evaluated for canopy height, forage supply, and chemical composition of leaf blade, stem and dead material. Average daily gain, weight gain per area, and the stocking rate were also evaluated. There were four grazing cycles because the grazing method was rotational stocking with seven days of occupation and 35 days of rest. The interaction between supplements and grazing cycles was not significant, and no effects of the supplements were found for any of the variables. The highest forage and leaf blade offerings were observed in the first grazing cycle. The highest levels of crude protein and lower neutral detergent fibre and lignin of pasture components were observed in cycles 3 and 4. The highest average daily gains per animal and per area were observed in cycles 1 and 2. Protein supplementation of sheep in Massai grass pastures promotes satisfactory gains during the dry season, and Leucaena and Gliricidia hays can be used as protein sources instead of soybean meal.
Keywords: Gliricidia sepium, leguminous, Leucaena leucocephala, pasture
Effects of soil type on density of trees and nutritive value of tree leaves in selected communal areas of South Africa
Authors: Ravhuhali K.E. , Mlambo V , Beyene T.S. , Palamuleni L.G. 
Published: June 2020

This study aimed to describe the distribution and nutritive value of woody species growing in clay-loamy and red-brown sand from selected localities of North West, South Africa. Three 2.2 km transects, radiating from homesteads, which served as replicates, were established at each of four selected grazing areas. Nine 10 × 10 m homogenous vegetation units (HVU), 20 m apart, were marked in each transect. Woody plant density, height and canopy cover (CC), were recorded, and chemical properties and degradability via in vitro ruminal fermentation of harvested leaves were measured. Raisin bush (Grewia flava), Buffalo thorn (Ziziphus mucronata) and Camel thorn (Vachellia erioloba) were the common species across both soil types. Soil type influenced (P <0.05) plant density, CC, total tree equivalent (TTE) and plant height. Areas with red-brown sandy soil had higher (P <0.05) total plant density (827.7 plant/ha), CC (9.6%) and TTE (2886.4 TTE/ha) than those with clay-loamy soil. Vachellia erioloba leaves in clay-loamy soil had the highest (P <0.05) crude protein content (151.2 g/kg DM). Leaves of Searsia lancea species that were harvested from both the clay-loamy and red-brown sandy soils had the highest (P <0.05) amounts of condensed tannins (0.915 AU550/200 mg and 0.917 AU550/200 mg, respectively). Searsia lancea leaves had the lowest (P <0.05) in vitro ruminal nitrogen degradability values in both soil types. The leaves of Z. mucronata and G. flava leaves have potential as protein supplements for ruminants owing to their higher crude protein content and in vitro ruminal N degradability.
Keywords: canopy cover, feeding value, plant height, semi-arid, species diversity, tree equivalent
Chemical, nutritive, fermentation profile and gas production of citrus pulp silages, alone or combined with maize silage
Authors: Ülger İ , Beyzi S.B. , Kaliber M , Konca Y 
Published: June 2020

Quality attributes of citrus pulp silages that were ensiled alone and combined with maize silage were determined. Fresh samples of lemon, orange and tangerine pulps, maize plants and their combinations were fermented in glass jars for 90 days at about 20 - 25 °C. Treatments included i) 100% maize silage as control (MS); ii) 100% lemon pulp silage (LPS); iii) 100% orange pulp silage (OPS); iv) 100% tangerine pulp silage (TPS); v) 50% LPS and 50% maize silage (LPS + MS); vi) 50% OPS and 50% MS; and vii) 50% TPS and 50% maize silage (TPS + MS). The pH differed among treatment groups. The highest and lowest pH values were recorded for MS group and the OPS + MS group, respectively (3.84 vs. 3.51). The highest dry matter (DM), crude fibre (CF), neutral detergent fibre (NDF), acid detergent fibre (ADF) and hemicellulose (HEM) were observed for MS (P <0.01). Citrus pulp silages alone had significantly greater total digestible nutrients (TDN), organic matter (OM) and non-fibre carbohydrate (NFC) values than MS and the combined silages (P <0.01). Maize silage had higher lactic acid (LA) (101.2 g/kg DM) and acetic acid (AA) (49.3 g/kg DM) concentrations than the citrus groups (P <0.05). In vitro gas production (TG), methane (CH4), metabolizable energy (ME) and organic matter digestibility (OMD) of the silages were similar (P >0.05). Thus, citrus pulps can be ensiled in spite of their moisture content. However, to increased DM and nutrient content, the citrus pulps should be ensiled with 50% maize.
Keywords: fermentation metabolites, methane production, organic matter digestibility
Spraying opened sugar beet pulp silage with oregano essential oil helps to sustain quality and stability
Authors: Çayıroğlu H , Filik G , Coşkun İ , Gül Filik A , Çayan H , Şahin A 
Published: June 2020

This study was conducted to determine the effects of spraying oregano essential oil (OEO) onto sugar beet pulp silage (SBPS) on silage quality and aerobic stability after opening. A factorial experiment with three replicates of three treatments and four time periods was conducted using laboratory-type plastic silos. The treatments were an untreated control, silage sprayed with 10 ml/75 cm2 OEO, and silage sprayed with 20 ml/75 cm2 OEO. The silages were sampled at 0, 72, 120, and 168 hours after spraying. Temperature, L*, a*, and b* colour values, pH, water-soluble carbohydrates, crude nutrient contents, Fleig score, metabolizable energy (ME) value, lactic acid bacteria (LAB), total live bacteria (TLB), yeast, and mould formation were assessed. Spraying OEO onto SBPS did not affect L*, a*, and b* values, pH, water-soluble carbohydrates, and Fleig score values, but decreased temperature. Spraying OEO onto the silage increased organic matter, ether extract, acid detergent fibre, neutral detergent fibre and acid detergent lignin contents without affecting crude protein, crude fibre, nitrogen free extract, and ME contents. Irrespective of treatment, crude protein, ether extract, acid detergent fibre, acid detergent lignin, nitrogen free extract, Fleig score, and ME contents of silages increased with time after spraying. The OEO spraying reduced LAB, TLB, and yeast contents in silages. In conclusion, OEO spraying onto opened SBPS reduced LAB, TLB, and yeast formation and stopped mould growth up to 72 hours without affecting their nutritional properties, suggesting that OEO could be used to ensure the stability of SBPS.
Keywords: aerobic stability, mould growth, silage microbiology, nutrients, feeding management
Effects of silage sealing films on fermentation dynamics of ensiled maize and nutrient utilization by Damara rams
Authors: Ndleleni N.W. , Malebana I.M.M. , Du Toit C.J.L. , Nephawe K.A. , Meeske R , Nkosi B.D. 
Published: June 2020

An experiment was conducted to evaluate the effects of two silage sealing films on whole crop maize (WCM) fermentation, aerobic stability and nutrient digestion by rams. Prior to ensiling (day 0), triplicate samples of the WCM were collected to determine dry matter, pH, water-soluble carbohydrates (WSC), lactic acid (LA) bacterial counts and nutrient concentration. A single bunker silo was divided into eight sections that were ensiled using either a standard polyethylene film (PE) or an orange oxygen barrier (OB) Silostop film for 180 days. After 180 days of ensiling, six silage samples were collected from each replicate. Three samples were used for nutrient analysis and the other three to determine aerobic stability. Sixteen four-year-old Damara rams with an average live weight of ± 54 kg were housed individually in wooden pens (2.2 m2) to determine digestibility of nutrient in the silage. The digestibility study was conducted as a switchover design with four feeding phases. The silage was supplemented daily with 1% urea and fed to the rams ad libitum. Nutritional value of the silage was not (P >0.05) affected by the ensiling films. The OB-ensiled maize had higher (P <0.05) LA, lower pH, CO2 production and yeast and mould populations, and lower WSC compared with the PE-ensiled maize. Dry matter intake, nutrient digestion and nitrogen balance of rams fed the silage were not affected (P >0.05) by treatments. The OB film improved the fermentation and aerobic stability of WCM silage but did not influence its nutrient utilization by rams.
Keywords: cereals, digestibility, forage, rams, nitrogen, supplementation