Bayesian Mass Averaging in Rigs and Engines

This paper introduces the Bayesian mass average and details its computation. Owing to the complexity of flow in an engine and the limited instrumentation and the precision of the sensor apparatus used, it is difficult to rigorously calculate mass averages. Building upon related work, this paper views any thermodynamic quantity's spatial variation at an axial plane in an engine (or a rig) as a Gaussian random field. In cases where the mass flow rate is constant in the circumferential direction but can be expressed via a polynomial or spline radially, this paper presents an analytical calculation of the Bayesian mass average. In cases where the mass flow rate itself can be expressed as a Gaussian random field, a sampling procedure is presented to calculate the Bayesian mass average. Examples of the calculation of the Bayesian mass average for temperature are presented, including with a real engine case study where velocity profiles are inferred from stagnation pressure measurements.

Onset and stabilization of delay-induced instabilities in piezoelectric digital vibration absorbers

The stability of a piezoelectric structure controlled by a digital vibration absorber emulating a shunt circuit is investigated in this work. The formalism of feedback control theory is used to demonstrate that systems with a low electromechanical coupling are prone to delay-induced instabilities entailed by the sampling procedure of the digital unit. An explicit relation is derived between the effective electromechanical coupling factor and the maximum sampling period guaranteeing a stable controlled system. Since this sampling period may be impractically small, a simple modification procedure of the emulated admittance of the shunt circuit is proposed in order to counteract the effect of delays by anticipation. The theoretical developments are experimentally validated on a clamped-free piezoelectric beam.

The Impact of a Graded Maximal Exercise Protocol on Exhaled Volatile Organic Compounds: A Pilot Study

Exhaled volatile organic compounds (VOCs) are of interest due to their minimally invasive sampling procedure. Previous studies have investigated the impact of exercise, with evidence suggesting that breath VOCs reflect exercise-induced metabolic activity. However, these studies have yet to investigate the impact of maximal exercise to exhaustion on breath VOCs, which was the main aim of this study. Two-litre breath samples were collected onto thermal desorption tubes using a portable breath collection unit. Samples were collected pre-exercise, and at 10 and 60 min following a maximal exercise test (VO2MAX). Breath VOCs were analysed by thermal desorption-gas chromatography-mass spectrometry using a non-targeted approach. Data showed a tendency for reduced isoprene in samples at 10 min post-exercise, with a return to baseline by 60 min. However, inter-individual variation meant differences between baseline and 10 min could not be confirmed, although the 10 and 60 min timepoints were different (p = 0.041). In addition, baseline samples showed a tendency for both acetone and isoprene to be reduced in those with higher absolute VO2MAX scores (mL(O2)/min), although with restricted statistical power. Baseline samples could not differentiate between relative VO2MAX scores (mL(O2)/kg/min). In conclusion, these data support that isoprene levels are dynamic in response to exercise.

ETHOS: a multi-label hate speech detection dataset

Online hate speech is a recent problem in our society that is rising at a steady pace by leveraging the vulnerabilities of the corresponding regimes that characterise most social media platforms. This phenomenon is primarily fostered by offensive comments, either during user interaction or in the form of a posted multimedia context. Nowadays, giant corporations own platforms where millions of users log in every day, and protection from exposure to similar phenomena appears to be necessary to comply with the corresponding legislation and maintain a high level of service quality. A robust and reliable system for detecting and preventing the uploading of relevant content will have a significant impact on our digitally interconnected society. Several aspects of our daily lives are undeniably linked to our social profiles, making us vulnerable to abusive behaviours. As a result, the lack of accurate hate speech detection mechanisms would severely degrade the overall user experience, although its erroneous operation would pose many ethical concerns. In this paper, we present ‘ETHOS’ (multi-labEl haTe speecH detectiOn dataSet), a textual dataset with two variants: binary and multi-label, based on YouTube and Reddit comments validated using the Figure-Eight crowdsourcing platform. Furthermore, we present the annotation protocol used to create this dataset: an active sampling procedure for balancing our data in relation to the various aspects defined. Our key assumption is that, even gaining a small amount of labelled data from such a time-consuming process, we can guarantee hate speech occurrences in the examined material.

Relative free-energy calculations for scaffold hopping-type transformations with an automated RE-EDS sampling procedure

The calculation of relative free-energy differences between different compounds plays an important role in drug design to identify potent binders for a given protein target. Most rigorous methods based on molecular dynamics simulations estimate the free-energy difference between pairs of ligands. Thus, the comparison of multiple ligands requires the construction of a “state graph”, in which the compounds are connected by alchemical transformations. The computational cost can be optimized by reducing the state graph to a minimal set of transformations. However, this may require individual adaptation of the sampling strategy if a transformation process does not converge in a given simulation time. In contrast, path-free methods like replica-exchange enveloping distribution sampling (RE-EDS) allow the sampling of multiple states within a single simulation without the pre-definition of alchemical transition paths. To optimize sampling and convergence, a set of RE-EDS parameters needs to be estimated in a pre-processing step. Here, we present an automated procedure for this step that determines all required parameters, improving the robustness and ease of use of the methodology. To illustrate the performance, the relative binding free energies are calculated for a series of checkpoint kinase 1 inhibitors containing challenging transformations in ring size, opening/closing, and extension, which reflect changes observed in scaffold hopping. The simulation of such transformations with RE-EDS can be conducted with conventional force fields and, in particular, without soft bond-stretching terms.

Predisposing Factors to Drug Abuse Among In-School Adolescents in Ilorin, Kwara State, Nigeria

Drug abuse among in-school adolescents is a problem which the government of Nigeria and indeed some other countries are yet to find a lasting solution to. Drug abuse among school children can disrupt the smooth running of teaching and learning in school. One of the ways of solving the problem is by trying to find out what leads in-school adolescents into the act. The objectives of this study were to examine the predisposing factors to drug abuse among in-school adolescents in Kwara State and to examine the influence of the variables of gender, age, religion and level of study on the respondents’ response on the predisposing factors. A descriptive research design was adopted for the study. The population for the study comprised of the adolescents in secondary school and university. A sample of 403 students were selected through a multistage sampling procedure in order to participate in the study. Data was collected via a questionnaire titled ‘Predisposing Factors to Drug Abuse (PFDA)’. The questionnaire was validated by experts in test and measurement design. It has a reliability coefficient of 0.68 which adjudged the instrument to be reliable. Data was analysed with mean, rank order, t-test and analysis of variance. Hypotheses were tested at a 0.05 level of significance. Findings showed that the factors that predispose in-school adolescents to drug abuse were: peer influence, depression, lack of good parental care, low self-esteem, poor academic performance, among other factors. Findings further revealed that age, gender, religion and level of education did not make the respondents differ in their responses on the predisposing factors to drug abuse among in-school adolescents. It is recommended that counsellors, parents and stake holders in education should initiate a serious campaign regarding sensitization against drug abuse. It is also recommended that academic programs should be learner-centred.

Prevalence of Infections Bronchities Virus at Four Selected Districts (Damot Gale, Sodozuri, Humbo and Kindokoy) In Southern Nations, Nationalities and Peoples

Infectious bronchitis is an important virial disease affecting poultry production which causes significant economic losses. A cross-sectional study was carried out from November 2019 to January 2020. To estimating the prevalence of infectious bronchitis and determines the risk factors. A total 420 poultry were by a simple random sampling procedure. Data was analyzed using STATA version 11. Chi square test and logistic regression analysis were used to determine the association between prevalence of infectious bronchitis and potential risk factors. From the total 420 poultry examined for infectious bronchitis were found positive. There was significance difference between the risk factors and bronchitis infections. More infectious bronchitis infected poultry were found in kindokoy 90.4%, odd ratio: 0.3 Confidence Interval :0.1-0.7, p = 0.00 than humbo, sodozuri and damotgale. There was high prevalence of infectious bronchitis in gerater than 6 months than less than 3 months and between 3 and 6-month age of poultry. The presence of infectious bronchitis in poultry production might entail morbidity and mortality. Therefore, further detailed molecular epidemiological studies are warranted. Good hygienic and husbandry practices are essential to limit the spread of infection

The Determinants of Agricultural Crop Productivity among Smallholder Households in Haramaya Distinct, Eastern Ethiopia

The agricultural crop is a backbone in Ethiopia since the country's economy is mainly dependent on agriculture, which is dominated by subsistence smallholder farmers who are partially integrated into the market. The objective of this study was to identify the determinants of crop productivity among smallholder farmers in Haramaya distinct, Eastern Ethiopia. A two-stage random sampling procedure was employed to detect a sample containing 260 smallholder households in the study area. Data was collected through semi-structured questionnaire schedules administered to the selected household farmers. The features of smallholder farmers were analyzed through descriptive statistics and multiple linear regression models. The results indicated that the length of farming experience of the household head, number of economically active members in family, amount of organic fertilizer applied, irrigated land area, and soil fertility status of farmland were the significant determinants of agricultural crop productivity. To increase the production and productivity of smallholder farms, the farmers were provided with land irrigation. Based on these findings, the study recommends the provision of organic fertilizer to farmers. Policies should also target supplying improved technology and improved seed to enhance agricultural crop production in Ethiopia.

Religious Institutions and Poverty Reduction: Evidence from Akwa Ibom State, Nigeria

In spite of the numerous poverty reduction policies and programs of successive administrations in Nigeria, the generality of the populace are still in a web of deprivation and hunger. It is apparent that government is unable to stem the tide of poverty and thus the need for surrogate stakeholders to lift the poor out of poverty. Therefore, an empirical study was conducted to estimate the factors influencing the willingness of religious institutions to undertake poverty reduction programs for it members and the constraints limiting their ability to initiate programs that will ameliorate the suffering of poor members in the congregation. A total of 60 churches were sampled through the multistage sampling procedure and information were elicited using questionnaire. Data were analyzed using probit model and Kendall’s coefficient of concordance. Result revealed that the most critical factors influencing the willingness of churches to undertake programs that will lift poor members of the congregation out of poverty were age and educational level of the church leaders, size of congregation, church income and age of the church. Result of Kendall’s coefficient of concordance indicated that there was 54 percent (moderate agreement) between the ranking of constraints associated with the willingness of churches to undertake programs that will lessen the pains of poverty among its members. Findings further showed that the top five most limiting constraints were lack of finance, lack of trained personnel, inadequate knowledge about the programs, unfavorable government policies and low membership strength.