Automatic Modulation Recognition Using Minimum-Phase Reconstruction Coefficients and Feed-Forward Neural Network

Sunday Ajala,Emmanuel Adetiba,Oluwaseun T. Ajayi,Abdultaofeek Abayomi,Anabi Hilary Kelechi,Joke A. Badejo,Sibusiso Moyo,Murimo Bethel Mutanga 한국정보과학회 2022 Journal of Computing Science and Engineering Vol.16 No.1

Identification of signal waveforms is highly critical in 5G communications and other state-of-the-art radio technologies such as cognitive radios. For instance, to achieve efficient demodulation and spectrum sensing, cognitive radios need to implement automatic modulation recognition (AMR) of detected signals. Although many works have been reported in the literature on the subject, most of them have mainly focused on the additive white Gaussian noise (AWGN) channel. However, addressing the AWGN channel, only, does not sufficiently emulate real-time wireless communications. In this paper, we created datasets of six modulation schemes in GNU Radio. Wireless signal impairment issues such as center frequency offset, sample rate offset, AWGN, and multipath fading effects were applied for the dataset creation. Afterward, we developed AMR models by training different artificial neural network (ANN) architectures using real cepstrum coefficients (RCC), and minimum-phase reconstruction coefficients (MPRC) extracted from the created signals. Between these two features, MPRC features have the best performance, and the ANN architecture with Levenberg-Marquardt learning algorithm, as well as logsig and purelin activation functions in the hidden and output layers, respectively, gave the best performance of 98.7% accuracy, 100% sensitivity, and 99.33% specificity when compared with other algorithms. This model can be leveraged in cognitive radio for spectrum sensing and automatic selection of signal demodulators.

The physicochemical, safety and antimicrobial properties of Phyllanthus amarus herbal cream and ointment

Tolulope O. Ajala,Mbang N. Femi-Oyewo,Oluwatoyin A. Odeku,Oluwasanmi O. Aina,Adebowale B. Saba,Olayinka O. Oridupa 한국약제학회 2016 Journal of Pharmaceutical Investigation Vol.46 No.2

The ethanol extract of Phyllanthus amarus (Schum and Thonn), a plant of ethnomedicinal importance, was formulated into herbal cream and ointment and evaluated using physicochemical, safety and antimicrobial properties. The extract was obtained by maceration and the antimicrobial properties tested on clinically isolated pathogenic bacteria (Staphylococcus aureus and Pseudomonas aeruginosa) and dermatophytes (Trichophyton rubrum and Candida albicans) using established methods. Cream and ointment formulations containing 1–10 % w/w extract was prepared and 4 % w/w humectant (glycerin) was incorporated into the cream while 5 % w/w surfactant (cetomacrogol 1000) was incorporated to the ointment. The results showed that the pH of the formulations was acidic and the viscosity ranged from 1250 to 4950 cP for ointments and 570–1233 cP for creams. The presence of humectant and surfactant significantly (p\0.05) reduced the viscosities of the formulations. The results of dermal irritation showed negligible irritation index while subchronic toxicity tests showed that the formulations did not cause any visible lesions in the skin of the animals after application for twenty-one days. The in vitro antimicrobial properties of formulations were concentration-dependent with the creams showing higher activity. Furthermore, the in vivo activity of the cream on S. aureus showed increased antibacterial activity with increase in extract concentration and humectant presence. The herbal cream and ointment of Phyllanthus amarus extract had acceptable physicochemical and safety profiles with significant (p\0.05) in vitro and in vivo antimicrobial activity. Thus, the formulations could be useful in the treatment of skin infections instead of using the extract for bathing and rubbing.

Chrysophyllum albidum mucilage as a binding agent in paracetamol tablet formulations

Tolulope O. Ajala,Olufunke D. Akin-Ajani,Chinemerem Ihuoma-Chidi,Oluwatoyin A. Odeku 한국약제학회 2016 Journal of Pharmaceutical Investigation Vol.46 No.6

Chrysophyllum mucilage obtained from the fruit of Chrysophyllum albidum (Family Sapotaceae) has been characterised and evaluated as a binding agent in comparison with methylcellulose in paracetamol tablet formulations. Chrysophyllum mucilage was characterised using elemental and proximate analyses as well as material properties. The Heckel and Kawakita plots were used to assess the compressional properties and the tablet properties were evaluated using tensile strength, friability, disintegration and dissolution times. The results showed the presence of calcium, magnesium, potassium, sodium, manganese, iron, copper, zinc and absence of heavy metals from the mucilage. The mucilage exhibited excellent flow and swelling properties, but poor water solubility. The viscosity of chrysophyllum mucilage increased with decrease in temperature in a similar manner with methylcellulose. C. albidum mucilage when used as a binder in paracetamol tablet formulation induced faster onset of plastic deformation and higher amount of total plastic deformation than methylcellulose. The results of the tablet properties showed that the tensile strength, disintegration and dissolution times, increased with increase in binder concentration while friability decreased. Tablets containing chrysophyllum mucilage as binder also had lower tensile strength, disintegration and dissolution times but higher friability values than those containing methylcellulose. However, tablets containing chrysophyllum mucilage at low concentrations conformed to pharmacopeial standard on disintegration indicating its potential usefulness as binder for immediate release tablets. Thus, C. albidum mucilage could be used as an alternative binding agent in pharmaceutical tablets.

The effect of pharmaceutical properties on the acid neutralizing capacity of antacid oral suspensions

Tolulope O. Ajala,Boladale O. Silva 한국약제학회 2015 Journal of Pharmaceutical Investigation Vol.45 No.5

Acid neutralizing capacity (ANC) of antacids is an important indicator of the efficacy of such products. The purpose of this study is to evaluate the effect of pharmaceutical properties on the ANC of antacid oral suspensions. Fifteen antacid oral suspensions randomly sourced from different manufacturers and coded A1-A15 were assessed using ANC, raft formation, sedimentation profiles, ease of re-dispersibility, density, alkalinity, particle size, viscosity and rheological patterns. The effects of the pharmaceutical properties were discussed on the ANC and conclusions drawn. The results showed that ten (66.67 %) of the samples passed the ANC test among which 5 (83.33 %) were nonsedimenting highly viscous suspensions. One sample (A5) presented raft formation. Sedimentation volume reduces with time, ease of re-dispersibility was in seconds and the density range for all samples was 1.06–1.26 g/mL. The particle sizes of the antacid oral suspensions were within the range for coarse dispersions. The viscosity values ranged from 39.33 ± 1.53 to 2508 ± 24.33 cp. The rheogram of A3 shows a Newtonian flow with a regression coefficient of 0.999 and it had the least ANC. Other samples present non- Newtonian flow in a pseudoplastic pattern. Comparison of the viscosity of samples with ANC shows no direct relationship between the two variables although most samples with low viscosity failed the ANC test. The acid neutralizing capacity of the antacid oral suspensions is influenced by the dynamics of different parameters including type of active pharmaceutical ingredient, sedimentation profile, viscosity and overall rheology of the suspension.

An Experimental Comparison of Three Machine Learning Techniques for Web Cost Estimation

Olawande Daramola,Ibidun Ajala,Ibidapo Akinyemi 보안공학연구지원센터(IJSEIA) 2016 International Journal of Software Engineering and Vol.10 No.2

Many comparative studies on the performance of machine learning (ML) techniques for web cost estimation (WCE) have been reported in the literature. However, not much attention have been given to understanding the conceptual differences and similarities that exist in the application of these ML techniques for WCE, which could provide credible guide for upcoming practitioners and researchers in predicting the cost of new web projects. This paper presents a comparative analysis of three prominent machine learning techniques – Case-Based Reasoning (CBR), Support Vector Regression (SVR) and Artificial Neural Network (ANN) – in terms of performance, applicability, and their conceptual differences and similarities for WCE by using data obtained from a public dataset (www.tukutuku.com). Results from experiments show that SVR and ANN provides more accurate predictions of effort, although SVR require fewer parameters to generate good predictions than ANN. CBR was not as accurate, but its good explanation attribute gives it a higher descriptive value. The study also outlined specific characteristics of the 3 ML techniques that could foster or inhibit their adoption for WCE.

Some Calculated (p,α) Cross-Sections Using the Alpha Particle Knock-On and Triton Pick-Up Reaction Mechanisms: An Optimisation of the Single-Step Feshbache-Kermane-Koonin (FKK) Theory

Olise, Felix S.,Ajala, Afis,Olaniyi, Hezekiah B. Korean Nuclear Society 2016 Nuclear Engineering and Technology Vol.48 No.2

The Feshbache-Kermane-Koonin (FKK) multi-step direct (MSD) theory of pre-equilibrium reactions has been used to compute the single-step cross-sections for some (p,${\alpha}$) reactions using the knock-on and pick-up reaction mechanisms at two incident proton energies. For the knock-on mechanism, the reaction was assumed to have taken place by the direct ejection of a preformed alpha cluster in a shell-model state of the target. But the reaction was assumed to have taken place by the pick-up of a preformed triton cluster (also bound in a shell-model state of the target core) by the incident proton for the pick-up mechanism. The Yukawa forms of potential were used for the proton-alpha (for the knock-on process) and proton-triton (for the pick-up process) interaction and several parameter sets for the proton and alpha-particle optical potentials. The calculated cross-sections for both mechanisms gave satisfactory fits to the experimental data. Furthermore, it has been shown that some combinations of the calculated distorted wave Born approximation cross-sections for the two reaction mechanisms in the FKK MSD theory are able to give better fits to the experimental data, especially in terms of range of agreement. In addition, the theory has been observed to be valid over a wider range of energy.

Chemometric Study, Homology Modeling of G Protein-Coupled Bile Acids Receptor (GPBAR_HUMAN) of Type-2 Diabetes Mellitus, Virtual Screening Evaluation, Drug-Likeness and ADME Prediction for Newly Designed Compounds

Shola Elijah Adeniji,Abduljelil Ajala,David Ebuka Arthur,Mustapha Abdullahi,Omole Isaac Areguamen 한국고분자학회 2022 Macromolecular Research Vol.30 No.9

Chemometric validation of the reported experimental activities of nicotinamide and carboxamide analogues against diabetes were determined via quantitative structure-activity relationship (QSAR) model using ATS1p, AATSC1m, nHother and RDF80p descriptors. Meanwhile, GPBAR_HUMAN with a UniProtKB code (Q8TDU6) for G protein-coupled bile acid was known as a potential drug target in human TGR5 of Type 2 diabetes mellitus (T2DM) whose crystal structure wasn’t found in the Protein Data Bank. With the aid of in-Silico approach via homology modeling helps to build a 3D protein (target) model with the availability of GPBAR_HUMAN sequence data. The swiss-Model online workspace was used to model the GPBAR_HUMAN receptor using the Cryo-EM structure of the INT-777-bound GPBAR-Gs complex with PDB code (7CFN) as a potential template. The built receptor was evaluated, validated, and used as a target protein for molecular docking simulation of some potent nicotinamide and carboxamide series. The virtual screening studies via molecular docking revealed the binding pockets, binding modes and poses of the GPBAR_HUMAN receptor with some prominent anti-diabetic agents. Analysis of these interactions led to computational design via a structure-based approach of new potent anti-diabetic compounds with significant binding scores and better interactions with the GPBAR_HUMAN receptor. Validation of the designed compounds via Drug-likeness and ADME prediction confirmed that these compounds are orally bioavailable with a good lipophilicity index for lipid environments and show zero violation to the drug assessment rules in order to be considered as drug candidates. Therefore, in-vitro and an in-vivo test to transform these findings into potent therapeutics are strongly recommended.

Understanding the Technical Properties of Delonix regia (HOOK.) RAF. Wood : A Lesser Used Wood Species

Funke Grace Adebawo,Olayiwola Olaleye Ajala,Olaoluwa Adeniyi Adegoke,Timileyin Samuel Aderemi 강원대학교 산림과학연구소 2023 Journal of Forest Science Vol.39 No.1

Properties of a lesser-used wood species were investigated to determine its potential for structural utilization. Trees of Delonix regia were felled and sampled at the base, middle and top and then sectioned to inner wood, middle wood, and outer wood for variation across the axial and radial directions. Hence, selected physical and mechanical properties as well as natural durability of D. regia along the radial and axial directions were examined. Obtained data were analyzed using analysis of variance (ANOVA) at 0.05. There was no significant difference in the Moisture content (MC) of the wood but specific gravity (SG) decreased from base to top ranging from 0.35-0.44. Water absorption, volumetric swelling, and volumetric shrinkage range from 46.18-51.86%, 2.57-4.02%, and 2.26-3.96% respectively along the axial plane. The weight loss for graveyard exposure and accelerated laboratory decay test ranged from 25.14-48.00% and 32.02-44.45% respectively. Modulus of Rupture and Modulus of Elasticity values range from 29.42-72.68 Nmm2 and 3,834.54-8,830.37 Nmm2 respectively. The SG values has confirmed the species as a medium density wood and values of other properties tested showed that the wood is dimensional stable and moderately resistance to fungi and termite. Hence, it could be used for light construction purposes such as furniture and other interior woodwork.

Formulation of floating metronidazole microspheres using cassava starch (Manihot esculenta) as polymer

Oluwatoyin A. Odeku,Aderemi A. Aderogba,Tolulope O. Ajala,Olufunke D. Akin‑Ajani,Adenike Okunlola 한국약제학회 2017 Journal of Pharmaceutical Investigation Vol.47 No.5

Floating gastroretentive microspheres have been used to prolong the gastric residence time after oral administration and improve the local effect of metronidazole in the stomach in the treatment of peptic ulcer caused by Helicobacter pylori. In the present study, cassava starch, obtained from the tubers of Manihot esculenta has been pregelatinized and used as polymer in combination with sodium alginate for the formulation of floating gastroretentive metronidazole microspheres. Metronidazole microspheres were prepared by ionic gelation method using pregelatinized cassava starch and sodium alginate at different concentrations as polymers and calcium chloride (2% w/v) as chelating agent. Sodium bicarbonate (2% w/w) was used as gas releasing agent. Microspheres were characterized using the particle size, swelling index, floating lag time (FLT), total floating time and drug release properties. Spherical discrete microspheres with size ranging from 1.52 to 2.23 mm were obtained with FLT of less than 5 min and drug entrapment efficiency of 42–60% w/w. The microsphere maintained buoyancy for over 19 h and the microspheres provided controlled release of metronidazole for up to 18 h. Drug release from the microspheres, swelling index and buoyancy depended on the concentration of cassava starch in the polymer blend. Formulations containing high concentration of cassava starch showing shorter floating lag time and faster drug release. Thus, buoyancy and rate of drug release appeared to be modulated by the concentration of cassava starch in the polymer blend. The results showed that pregelatinized cassava could be useful in the formulation of floating gastroretentive metronidazole microspheres.