Optimization of RBF-SVM hyperparameters using genetic algorithm for face recognit

Manual grid-search tuning of machine learning hyperparameters is very time-consuming. Hence, to curb this problem, we propose the use of a genetic algorithm (GA) for the selection of optimal radial-basis-function based support vector machine (RBF-SVM) hyperparameters; regularization parameter C and cost-factor γ. The resulting optimal parameters were used during the training of face recognition models. To train the models, we independently extracted features from the ORL face image dataset using local binary patterns (handcrafted) and deep learning architectures (pretrained variants of VGGNet). The resulting features were passed as input to either linear-SVM or optimized RBF-SVM. The results show that the models from optimized RBFSVM combined with deep learning or hand-crafted features yielded performances that surpass models obtained from Linear-SVM combined with the aforementioned features in most of the data splits. The study demonstrated that it is profitable to optimize the hyperparameters of an SVM to obtain the best classification performance. Keywords: Face Recognition, Feature Extraction, Local Binary Patterns, Transfer Learning, Genetic Algorithm and Support Vector  Machines

Yield stability analysis of pearl millet hybrids in Nigeria

Genotype x environment interaction in pearl millet [Pennisetum glaucum (L.) R.Br.] was studied for grain yield by growing 90 genotypes consisting of 81 hybrids and 9 inbred parents at 5 locations for 2 years. Genotype x environment interaction was observed, a large component of which was accounted for by non-linear regression on the environment means. Although the linear portion was significant, its magnitude was smaller than that of the non-linear component indicating the significance of environmental effects on the genotypes. Six hybrids were found to be stable across the environments. They yielded above the average mean yield of all the genotypes under test, with a slope of unity and the mean square due to deviation from regression equal to zero.Keywords: Genotype x environment interaction, yield, stability, pearl mille

Prevalence studies of human T-Lymphotrophic virus type 1 among pulmonary tuberculosis patients in Dutse metropolis, north-western Nigeria

Human T-lymphotrophic virus type 1 (HTLV-1) is a causative agent of tropic spastic paraparesis and adult Tcell leukaemia, Information regarding the involvement of HTLV-1 in presentation of some subclinical immune  suppression that may results in increased rate of HIV and TB infections has long been documented. Sixty (60) Confirmed Pulmonary TB subjects  consisting of 41 males and 19 females were recruited in this study,  Tuberculosis was confirmed by collecting their sputum samples and analysed using GeneXpert. The prevalence of HTLV-1 IgG antibodies among TB subjects was 6.6%, while that of IgM was 1.6%. Accordingly, sexually active couple  group has the highest prevalence of 2.3% when compared to single and widow categories, age group 15-24 has the highest percentage of 3.3% for HTLV-1 IgG antibodies.Key words: HTLV-1, Tuberculosis, IgG, IgM

Comparative analysis of genetic crossover operators in knapsack problem

The Genetic Algorithm (GA) is an evolutionary algorithms and technique based on natural selections of individuals called chromosomes. In this paper, a method for solving Knapsack problem via GA (Genetic Algorithm) is presented. We compared six different crossovers: Crossover single point, Crossover Two point, Crossover Scattered, Crossover Heuristic, Crossover Arithmetic and Crossover Intermediate. Three different dimensions of knapsack problems are used to test the convergence of knapsack problem. Based on our experimental results, two point crossovers (TP) emerged the best result to solve knapsack problem.Keywords: Genetic Algorithm, Crossover, Heuristic, Arithmetic, Intermediate, Evolutionary Algorith

Herpetofauna community diversity and composition of a changing coastal wetland in Ghana

Despite concern about the negative effects of tropical wetland loss and degradation on biodiversity, data on impacts on amphibians and reptiles, remain scarce. Here, we assessed the herpetofauna at the Muni-Pomadze ramsar site for the first time in 14 years and report on the changes in diversity and composition at the coastal wetland. The methodology involved pitfall trapping, refuge examination and acoustic searches in the forest and grassland/thickets habitats, as well as interviews of a cross-section of local inhabitants. Overall, 39 herpetofauna species were recorded at the study area. These comprised 19 amphibian species belonging to six families (Bufonidae, Ranidae, Hemisotidae, Hyperoliidae, Arthroleptidae and Petropedetidae), and 20 reptile species of nine families. The reptiles consisted of four lizard families (Agamidae, Scincidae, Gekkonidae and Varanidae), four snake families (Boidae, Colubridae, Elapidae and Viperidae) and one chelonian family (Pelome dusidae). Three families, Hemisotidae, Arthroleptidae and Viperidae are first records for the study area. Survey at the site in 1998 recorded 28 species, comprising 15 species of reptiles and 13 species of amphibians. Two families (Microhylidae and Testudinidae) recorded in 1998 were not recorded in the present survey. Although we recorded higher species richness in the present study, there was no significant change in the proportion of savanna and generalist species in the forest because of compensatory dynamics. Given that habitat loss at the patch and landscape levels is the main threat to herpetofauna at the ramsar site, conservation managers should focus on preventing further deforestation, particularly at Yenku Block A Forest Reserve to preserve the herpetofana at the Muni-Pomadze ramsar site

Implication of Career Development and Demograpic Factors on Quality of Work Life

The objective of this research is to study the implication of career development and demographic factors on quality of work life. The research was done cross sectional, by conducting 429 subjects who work in public service. Data was collected from a set of questionnaires which consists of scale of quality of work life, scale of career development and bio data. The result of Pearson correlation analysis indicated positive and significant correlation between career development and quality of work life. The correlation indicated that the positive perception of career development, the higher of quality of work life. Also, the Point Biserial correlation indicated demographic factors such as; sex, age, education, length of service and marital status showed positive and significant with quality of work life. These findings contribute to an understanding of ways by top management in attempts to attain a quality of work life between the needs of the employees and the needs of the organization

Productivity of Apple as Influenced by Rates of Nitrogen, Phosphorus and Irrigation Interval

Field experiment was conducted on an established orchard of the Kaduna State Agricultural Development Project (KADP) at Maigana during the 1998- 2001 to evaluate the effect of nitrogen, phosphorus and irrigation interval on some selected growth attributes of apple. The treatments consisted of four levels of nitrogen (0, 60, 120 and 180 kg N h -1, three levels of phosphorus (0, 22 and 44) and irrigation intervals (3, 5 and 7 days). Treatments were laid out in a split plot design with factorial combination of nitrogen and irrigation interval allocated to main plots and phosphorus assigned to sub-plots and replicated three times. The result showed that application of nitrogen up to 180 kg N ha -1 resulted to taller plants with more branches and wider canopy as well as thicker stem and heavier fruit yield. Likewise, applications of phosphorus up to 44 kg P ha -1 resulted to taller plants, more branches, wider canopy, thicker stem and heavier fruit yield. There was inconsistency in response of the parameters to irrigation interval, however the yield responded up to 7 days irrigation interval. It can be concluded that for proper apple growth, application of 180 kg N ha -1 plus 44 kg P ha -1, with 7 days irrigation interval should be adopted. Keywords: fruit yield, nitrogen, phosphorus, irrigation and nitrogen conten

Effect of Heat Treatment and Sulfuric Acid Anodization on Corrosion Resistance of Aluminum Alloy (AA7075)

This paper, studied the effect of heat treatment and anodization on corrosion resistance of aluminum alloy 7075 (AA7075), with a view to improving its corrosion resistance. Microstructure and micro hardness of the anodic film of the samples were studied with the aid of optical metallurgical microscope and automated micro hardness testing machine. Linear polarization methods were used to assess the corrosion behaviour of the alloy in 0.5M HCl. The microstructure of the annealed sample showed formation of dendrites while precipitation hardened samples in palm kernel oil and SAE 40 engine oil showed precipitates of MgZn2. The SEMS result showed pores and micro cracks on the surfaces of the anodized samples, with the as cast and anodized sample in sulfuric acid exhibiting most compact with few pores. The as cast and sulfuric acid anodized sample shows highest micro hardness value of 205.33 HV, while the least value of 150.67 HV was recorded in sample precipitation hardened in SAE 40 engine oil and anodized in sulfuric acid. Analysis of the potentiodynamic polarization data and curves showed a linear relationship (decrease in icorr, decreases the corrosion rate) between current density and the corrosion rate in all the samples. Higher polarization resistance of 15.093 Ω/cm2 was recorded by the as cast and Sulfuric acid (SA) anodized sample while the precipitation treated in SAE 40 engine oil plus SA anodized sample recorded lowest polarization resistance of 5.2311 Ω/cm2. Heat treatment alone improves corrosion resistance of AA 7075 in 0.5 M HCl solution but heat treatment plus SA anodization does not improve corrosion resistance in the same environment

Returnable transport packaging in developing countries: drivers,barriers and business performance

This study, drawing on natural resource-based view, identifies drivers, barriers and the potential benefits of returnable transport packaging (RTP) – that is, the repeated use of packaging items – and conceptualises RTP as a technology and resource that supports organisational competitiveness. Specifically, it investigates the impact of RTP adoption on business performance, the effects of drivers, barriers and size of organisations. The data collection took place in Nigeria and South Africa. The findings suggest that RTP has a significant positive impact on business performance. Whilst prior studies seem to suggest that shrinkage and attrition are the major problems identified with the usage of RTP, our findings indicate that there are several other barriers affecting RTP adoption and the resultant performance advantage. The results also show that there is an increasing move towards adoption of RTP but some organisations are faced with financial constraints, especially the small and medium size enterprises. In addition, the results show that RTP is largely a ‘sustainability facing’ initiative with adopters motivated primarily by potential environmental, economic, social and operational benefits of adoption

Analytical study of flexible stimulation waveforms in muscle fatigue reduction

This paper presents the analytical study of flexible stimulation waveforms in muscle fatigue reduction for functional electrical stimulator (FES)-assisted hemiplegic muscle activities. The major challenge of muscle contraction induced by FES is early muscle fatigue which greatly limits activities such as FES-assisted standing and walking. The fixed stimulation pattern applied on a same motor unit has resulted the motor unit to be overworked and fatigue easily. Therefore, in this work, the stimulus parameters, which include the pulse width duration and the frequency were varied to create a few flexible stimulation waveforms using MATLAB/Simulink. The pulse width duration was modulated from 100µs – 500µs to generate five types of flexible stimulation waveforms such as Rectangular, Trapezoidal, Ramp Up, Ramp Down and Triangular. Concurrently, a few ranges of stimulus frequency were also used, which include 20Hz, 30Hz and 50Hz. The generated flexible stimulation waveforms were applied onto a humanoid muscle model to investigate and analyse the muscle output response and early muscle fatigue reduction. From the conducted simulation results and analyses, it was observed that flexible stimulation waveforms such as Triangular, Ramp Up and Ramp Down could reduce early muscle fatigue phenomenon by having lower average of negative slope, in the range of 0.012 to 0.013 for the muscle fitness. In contrast, the Rectangular and Trapezoidal shapes were found to have higher negative slope of muscle fitness in the range of 0.028 to 0.031. The Ramp Down shape was found to have the lowest average of negative slope (0.012) while Rectangular was found to have the highest average of negative slope (0.031). Therefore, it can be concluded that flexible stimulation waveforms such Ramp Down, Ramp Up and Triangular shapes could reduce early muscle fatigue phenomenon with Ramp Down shape having the highest muscle fatigue reduction