Effective Activation Functions for Homomorphic Evaluation of Deep Neural Networks

CryptoNets and subsequent work have demonstrated the capability of homomorphic encryption (HE) in the applications of private artificial intelligence (AI). While convolutional neural networks (CNNs) are primarily composed of linear functions which can be homomorphically evaluated, layers such as the activation layer are non-linear and cannot be homomorphically evaluated. One of the most commonly used alternatives is approximating these non-linear functions using low-degree polynomials. However, it is difficult to generate efficient approximations and often, dataset specific improvements are required. This thesis presents a systematic method to construct HE-friendly activation functions for CNNs. We first determine the key properties in a good activation function that contribute to performance by analyzing commonly used functions such as Rectified Linear Units (ReLU) and Sigmoid. We then analyse the inputs to the activation layer and search for an optimal range of approximation for the polynomial activation. Based on our findings, we propose a novel weighted polynomial approximation method tailored to this input distribution. Finally, we demonstrate effectiveness and robustness of our method using three datasets; MNIST, FMNIST, CIFAR-10

Heavy Metal Levels in Pine (Pinus caribeae Morelet) Tree Barks as Indicators of Atmospheric Pollution Calabar Municipality, South Eastern Nigeria

Biomonitoring of the air quality in Calabar was carried out by analyzing barks from pine tree (Pinus caribeae Morelet). Barks were collected from trees along highways with heavy traffic; residential areas with low traffic and the control, and analysed using atomic absorption spectrophotometer for lead (Pb) and Manganese (Mn). The result showed the highest Pb level in the heavy traffic site U. J. Stadium by Calabar Road, 0.66± 02 mg/kg and lowest 0.01mg/kg in the control. Manganese was highest in the heavy traffic site, Stadium by Calabar Road 0.57± 0.02 mg/kg and lowest at the control 0.05± 0.01. The relatively low level of lead might be due to the unleaded petrol imported into the country Keywords: Bio-monitoring, Emission, Toxicity, Contamination, Pine bar

Heavy Metal Levels in Pine (Pinus caribeae Morelet L) Tree Barks as Biomonitors of Atmospheric Pollution in Calabar Municipality, South Eastern Nigeria

Biomonitoring of the air quality in Calabar was carried out by analyzing barks from pine trees (Pinus caribeae Morelet). Barks were collected from trees along highways with heavy traffic; residential areas with low traffic and the control (Cross River University of Technology, Staff Residential Area, Calabar); and analysed using atomic absorption spectrophotometer for lead (Pb) and manganese (Mn). The result showed the highest Pb level in the heavy traffic site U. J. Esuene Stadium by Calabar Road, 0.66± 0.02 mg/kg and lowest 0.01mg/kg in the control. Manganese was highest in the heavy traffic site, U. J. Esuene Stadium by Calabar Road 0.57± 0.02 mg/kg and lowest at the control 0.05± 0.01.mg/kg. The apparently low level of lead obtained in this study, compared to values that have been obtained in some other countries might be due to the unleaded petrol imported into this country. However the level of manganese might be due to its inclusion in petrol to improve its antiknock properties. Keywords: Biomonitoring, Emission, Toxicity, Contamination, Pine bar

Proposal of a New Porous Concrete Dosage Methodology for Pavements

Although porous concrete pavement design methods are mainly focused on maintaining high permeability rates in order to improve their ability to manage stormwater runoff, the mixture strength is paramount for its durability and service life. This paper proposes a new mixture design method for porous concrete, named PCD (porous concrete design), derived from the ACI 522R-10 and ACI 211.3R-02 standards. The aim is to improve mechanical strength in porous concrete mixtures, while ensuring enough permeability for its use in urban roads. With PCD methodology it is possible to obtain mechanical strengths 30% higher than those produced with ACI methodologies, while maintaining permeability rates close to 2 cm/s, lower than those obtained with ACI methods but still enough to manage extreme storm events. Finally, with the analytical Hierarchy Process (AHP) multi-criteria decision-making methodology and also bearing in mind safety variables, the best porous concrete mixtures are the ones produced with PCD methodology.This research was funded by the Spanish Ministry of Economy and Competitiveness and the European Union (ERDF) through the project SUPRIS.SUReS (Ref. BIA2015-65240-C2-1-R)

Professional variables and staff readiness to utilise internet-based channels for research communication in an Era of Covid-19

This study assessed the professional variables of academic staff in African varsities and their readiness to Utilise Internet-Based Channels for Research Communication in an era of Covid-19. Drawing from Maslow’s hierarchy of needs theory, the study was guided by four null hypotheses. The quantitative research method based on the virtual cross-sectional survey design was adopted. A total of 8,591 academics in African universities were the targeted demographic of this study. However, data were collected from a virtual snowball sample of 1,977 respondents (males, N = 1347; females, N = 630) from 24 African countries. A validated electronic survey, with three major aspects, was employed for data collection. The e-survey was released on the Association of African Universities' Telegram forum, which includes 1,622 participants from diverse African nations and regions. Members of the forum, who are all academics, were invited to complete the survey and publish it on their universities' internet-based forums. Coded data were analysed using descriptive and inferential statistics such as the Kruskal Wallis Non-parametric test. The non-parametric test was used because the data failed to meet the normality assumptions required to perform a parametric test. Results indicated, amongst others, that there are considerable variances in staff preparedness to use internet-based channels for research communication based on their educational credentials, educational qualification, rank and areas of research interest. According to the survey, academics with a doctoral degree; grade II lecturers; staff with 3 to 6 years of service; and staff in the medical sciences demonstrated a higher propensity of readiness to use internet-based channels for research communication. Based on these findings key theoretical, practical and research implications are discussed

Gender, age and staff preparedness to adopt Internet tools for research sharing during Covid-19 in African varsities

This study assessed the partial as well as the collaborative impact of age and gender on academic staff preparedness to adopt Internet tools for research sharing in African universities during Covid-19. Although evidence abounds in the literature on gender and age as they affect relatively, scholars’ utilisation of digital tools for research communication, such studies did not examine scholars’ preparedness to adopt from a broad perspective of Africa. This study was conducted based on the argument that the preparedness of scholars may affect their future interest to utilize digital tools for research sharing. A quantitative method, based on the descriptive survey research design, was adopted to provide answers to four prevailing research questions. The examination focused on a populace of 8,591 staff in African universities, nonetheless, information was gathered from 1,977 of them, who deliberately took part from 24 African nations. A validated electronic rating scale, which was mailed/posted to targeted participants, was used as the instrument for data collection. Gender and age significantly affected academic staff preparedness to adopt Internet tools for research sharing partially and interactively in African Universities during Covid-19. Female staff were more prepared than males to adopt internet tools for research sharing during the pandemic. Older lecturers reported a higher rate of preparedness than their younger colleagues to adopt Internet tools for research sharing during Covid-19. In light of these proofs, ramifications and proposals for future exploration are discusse

Students' awareness, willingness and utilisation of facebook for research data collection: Multigroup analysis with age and gender as control variables

Previous research has extensively analysed teachers' and students' Facebook use for instructional engagement, writing, research dissemination and e-learning. However, Facebook as a data collection mechanism for research has scarcely been the subject of previous studies. The current study addressed these gaps by analysing students' awareness, willingness, and utilisation of Facebook for research data collection [RDC]. This study aimed to predict students’ Facebook use for research data collection based on their awareness and willingness and to determine age and gender differences in such predictions. A sample of 11,562 students of tertiary institutions participated in an online survey. The researchers designed and validated the online survey. Exploratory Factor Analysis was used for dimensionality. Average Variance Extracted [AVE] was used for convergent validity, whilst the Fornel-Larcker criterion and Heterotrait-Monotrait ratio were used for discriminant validity. Composite reliability indices of .97, .94 and .90 proved the instrument’s three sub-scales usable. One sample t-test and multigroup analysis were conducted using SPSS 27 and Smart PLS 3. The study found high awareness but low usage of Facebook for RDC among Nigerian university students. Younger and male students showed higher willingness and actual use of Facebook for RDC. Awareness directly impacted by awareness, and acted as Facebook usage for RDC, with stronger impacts for males and students aged 19 to 28. Willingness was positively impacted and acted as a negative mediator between awareness and usage for some age groups and genders. These findings provide important insights into using Facebook for RDC among students in Nigerian universities and highlight the need to consider the impact of demographic factors such as age and gender when promoting social media platforms for academic purposes

Students' awareness, willingness and utilisation of facebook for research data collection: Multigroup analysis with age and gender as control variables

Previous research has extensively analysed teachers' and students' Facebook use for instructional engagement, writing, research dissemination and e-learning. However, Facebook as a data collection mechanism for research has scarcely been the subject of previous studies. The current study addressed these gaps by analysing students' awareness, willingness, and utilisation of Facebook for research data collection [RDC]. This study aimed to predict students’ Facebook use for research data collection based on their awareness and willingness and to determine age and gender differences in such predictions. A sample of 11,562 students of tertiary institutions participated in an online survey. The researchers designed and validated the online survey. Exploratory Factor Analysis was used for dimensionality. Average Variance Extracted [AVE] was used for convergent validity, whilst the Fornel-Larcker criterion and Heterotrait-Monotrait ratio were used for discriminant validity. Composite reliability indices of .97, .94 and .90 proved the instrument’s three sub-scales usable. One sample t-test and multigroup analysis were conducted using SPSS 27 and Smart PLS 3. The study found high awareness but low usage of Facebook for RDC among Nigerian university students. Younger and male students showed higher willingness and actual use of Facebook for RDC. Awareness directly impacted by awareness, and acted as Facebook usage for RDC, with stronger impacts for males and students aged 19 to 28. Willingness was positively impacted and acted as a negative mediator between awareness and usage for some age groups and genders. These findings provide important insights into using Facebook for RDC among students in Nigerian universities and highlight the need to consider the impact of demographic factors such as age an

Deciphering the introduction and transmission of SARS-CoV-2 in the Colombian Amazon Basin

La pandemia del SARS-CoV-2 ha obligado a las autoridades sanitarias de todo el mundo a tomar importantes decisiones para reducir su propagación. La epidemiología genómica se ha convertido en una herramienta valiosa para comprender las introducciones y la propagación del virus en una ubicación geográfica específica.The SARS-CoV-2 pandemic has forced health authorities across the world to take important decisions to curtail its spread. Genomic epidemiology has emerged as a valuable tool to understand introductions and spread of the virus in a specific geographic location