Miracle-dz/UniFAR-FTUs huggingface dataset:
Oil price volatility and US dollar exchange rate volatility of some oil-dependent economies

This paper examines the relationship and related causality patterns of oil price volatility and exchange rate volatility of a group of oil-dependent economies before and after the 2008–2009 global financial crisis. We employed weekly time-series data of oil price and exchange rates for 2000–2007 (pre-crisis) and 2010–2016 (post-crisis). United States dollar exchange rates are for Ghanaian cedi, Nigerian naira, Russian ruble, Indian rupee, South African rand, and the Euro. To investigate the volatility impacts that exist between oil price and exchange rates during both sub-sample periods, we merged Vector Autoregressive (VAR) with GARCH and EGARCH models in the form of Bivariate VAR-GARCH and VAR-EGARCH. We further adopted the Toda-Yamamoto causality test to investigate related causality patterns. Empirical findings revealed both bidirectional and unidirectional relationship between oil price volatility and the exchange rates volatility of four out of the six oil-dependent economies considered for the study. These findings were more prevalent in the post-crisis period than the pre-crisis period. We also confirmed both bidirectional and unidirectional causality pattern between oil price volatility and exchange rate volatility of the same four currencies as observed with the VAR results in both sub-sample periods.
Influence of fabrication tolerances on the surface accuracy of large antenna structures

One of the sources of error in radio frequency antennas is the lack of dimensional precision of the surface. This paper presents an approach for estimating the amount of error caused by random dimensional imperfections of the many structural elements which make up a truss-type antenna. A principle of equivalence between the analyses of statistical errors and of the natural vibration frequencies of the structure is developed. Examples are presented to show the application of this equivalence principle to the determination of average surface errors of several types and proportions of antenna structures.
Impacts of the COVID-19 Pandemic on Family Mental Health in Canada: Findings from a Multi-Round Cross-Sectional Study

Pandemic-related disruptions, including school, child care, and workplace closures, financial stressors, and relationship challenges, present unique risks to families’ mental health. We examined the mental health impacts of the coronavirus disease 2019 (COVID-19) pandemic among parents with children <18 years old living at home over three study rounds in May 2020 (n = 618), September 2020 (n = 804), and January 2021 (n = 602). Data were collected using a cross-sectional online survey of adults living in Canada, nationally representative by age, gender, household income, and region. Chi-square tests and logistic regression compared outcomes between parents and the rest of the sample, among parent subgroups, and over time. Parents reported worsened mental health compared with before the pandemic, as well as not coping well, increased alcohol use, increased suicidal thoughts/feelings, worsened mental health among their children, and increases in both negative and positive parent–child interactions. Mental health challenges were more frequently reported among parents with pre-existing mental health conditions, disabilities, and financial/relationship stressors. Increased alcohol use was more frequently reported among younger parents and men. Sustained mental health challenges of parents throughout nearly a year of the pandemic suggest that intervention efforts to support family mental health may not be adequately meeting families’ needs. Addressing family stressors through financial benefit programs and virtual mental health supports should be further explored.
Multiple intensity reference interferometry for the correction of sub-fringe displacement non-linearities

Displacement measuring interferometers, commonly employed for traceable measurements at the nanoscale, suffer from non-linearities in the measured displacement that limit the achievable measurement uncertainty for microscopic displacements. Two closely related novel non-linearity correction methodologies are presented here that allow for the correction of non-linearities in cases where the displacement covers much less than a full optical fringe. Both corrections have been shown, under ideal conditions, to be capable of reducing all residual non-linearity harmonics to below the 10 pm level.
Performance enhancements in next generation wireless networks using network coding : a case study in WiMAX

In this thesis, we design and implement a network-coding-enhanced network architecture for next generation wireless networks. The architecture applies intra-session random linear network coding as a packet erasure code below the IP layer. Using WiMAX as a case study, a series of point-to-point single-interface experiments are conducted to compare the performance of the architecture to that of HARQ and ARQ mechanisms. The performance measures are packet loss percentage, throughput and file transfer delay. The experiments use the Global Environment for Network Innovations (GENI) WiMAX platforms. UDP traffic is considered; Iperf and UDP based File Transfer Protocol (UFTP) are used as measurement applications. The proposed architecture substantially decreases packet loss percentage from around 11-32% to nearly 0%. Compared to HARQ and ARQ mechanisms, the architecture can offer up to 5.9 times gain in throughput and 5.5 times reduction in end-to-end file transfer delay. Thesis Supervisor: Muriel Medard Title: Professor of Electrical Engineering Thesis Co-Supervisor: Marie-Jose Montpetit Title: Research Scientist Thesis Co-Supervisor: Kerim Fouli Title: Postdoctoral Fellow
Simple scalar finite element approach to optical rib waveguides

A simple approach based on the scalar finite element method is described for the evaluation of the effective index, modal field profile, and far-field pattern of the guided mode of an optical rib waveguide and of the coupling efficiency of a butt-joint structure of two single-moded rib waveguides. Calculations are performed for several different rib waveguide structures, and the accuracy of the present approach is examined and assessed by comparing the results obtained with the other existing methods.
Is Local Bias a Cross-Border Phenomenon? Evidence from Individual Investors’ International Asset Allocation

Extant literature consistently documents that investors tilt their domestic equity portfolios towards regionally close stocks (local bias). We hypothesize that individual investors’ local bias is not limited to the domestic sphere but instead also determines their international investment decisions. Our results confirm the presence of a cross-border local bias. Specifically, we show that the stockholdings of individual investors living within regional proximity to a foreign country display a significantly lower foreign investment bias towards investment opportunities in that country and that this drop in foreign investment bias levels is disproportionately driven by investments in regionally close neighbor-country companies. The impact of cross-border local bias on investors’ bilateral foreign equity investments is economically significant and holds even after controlling for previously identified explanations of international asset allocation.
Joint Response of Existing Pipe Culverts under Surface Live Loads

AbstractThis study investigates the field performance of culvert joints in five existing pipe culverts. Test culverts consisted of two corrugated metal culverts, two reinforced concrete culverts, and one high-density polyethylene culvert. Culverts were selected for backfill depths less than 1.5 m and inner diameters ranging from 0.9 to 2.1 m. Static loading was applied to the culverts by parking a heavily loaded truck at different positions above the culvert joint. Dynamic loading was applied by driving the truck over the culvert at speeds ranging from 8 to 48 km/h. Culvert deflections and strains were measured near one of the culvert’s joints. Separation at the joint was also measured. The results indicate that separation at the joint was quite significant at times. In the worst case, the measured separation at the joint was equal to 50% of the measured deflection. Strains measured near the joint in steel culverts were significantly smaller than the yield strain. The dynamic deflections were typically 1.
Evaluation of the Impact of Pedestrian Countdown Signals on Crossing Behavior

The objective of this research is to evaluate the impact of pedestrian countdown signals on crossing behavior at intersections. Data were collected by means of questionnaire and video recording at two signalized intersections: one was with pedestrian countdown signal and the other was with traditional signal. The questionnaire aims to reveal pedestrians' preference to countdown signals. It shows that 91.8% of pedestrians believe that countdown signals are helpful in determining the time to enter crosswalk, and 72.6% of pedestrians think that countdown signals are more comfortable for crossing. To evaluate effects of countdown signals, four measures of effectiveness, that is, proportion of compliers, adventurers, violators, and trapped pedestrians, are applied. Hypothesis testing results show that countdown signals can significantly increase proportions of compliers and reduce proportions of violators and trapped pedestrians compared with traditional signals. However, countdown signals have weak impact on adventurers since many pedestrians do not understand the meaning of flashing signal.
Electrical and Electronic Waste Management Practice by households in Shah Alam, Selangor, Malaysia

Increase in the end of life of electrical and electronic products depends on the economic growth of the country, population growth, market penetration, technology upgradation, and obsolescence rates. It can be assumed that the disposal of electronic products is fundamentally driven by the production of new ones. The management of electronic waste has become an environmental concern in many developing countries as urbanization continues to take place. Hence, this study was conducted in Shah Alam City which is the state capital of Selangor, Malaysia. The aim of this paper is to identify current electronic waste management practices by households in Shah Alam, Selangor. In other to ensure a higher response rate, face­to­face interviews were employed for primary data collection as the interview survey method. Information on knowledge level, attitude and practice on use and EEE disposal was collected using questionnaires. The findings show that the preferred methods of electronic waste disposal by Shah Alam residents are storage and sale as second­ hand equipment, is about 48% and 37% respectively. Only a fraction of electronic waste (22%) finds it way to recycling facilities as there is no efficient take­back scheme for consumers. Most of the households do not know where and how to dispose of electronic waste in a proper manner. Consequently, they resort to disposing electronic waste outside their premises together with other household wastes. The government needs to improve collaboration among stakeholders in order to enhance public awareness on electronic waste.
GRANSHOT Iron Granulation for Optimized Plant Logistics

This article describes GRANSHOT iron granulation technology, operational experience and the usability of the end product in steelmaking operations. The GRANSHOT granulation process converts liquid metal into granules by rapid solidification in water. A ready–to–use bulk material is produced directly from liquid metal, without any intermediate crushing and sieving steps and producing little to no fume emissions and no dust. The equipment is more robust than comparable size pig casters due to its simplicity and absence of moving components. A GRANSHOT plant decouples ironmaking and steelmaking operations when required, and can be designed to process the entire output of the blast furnace. Optimization of plant logistics is illustrated by means of cases. Operational experiences with GRANSHOT plants of different sizes installed at integrated steelmaking plants are discussed. Metallurgical properties are summarized, such as carbon content in the metal matrix that reduces the energy usage when used as feedstock for Electric Arc Furnaces (EAFs).
Permeability of High-Strength Concrete Containing Low Cement Factor

Coal-burning powerplants generate about 72,000,000 t (80,000,000 ton) of combustion by-products per year in the United States. Each tonne (I.I ton) of by-products used in lieu of portland cement in concrete saves about 7,600,000 kJ (7,150,000 Btu) of energy, and prevents 1 t (l.l ton) of CO2 released in the air due to avoided cement manufacture. This specific project was directed toward stud­ ying the influence of ASTM Class C fly ash on concrete permeability. A plain portland cement concrete mixture was proportioned to have a 28-day compressive strength of 40 MPa. Concrete mixtures were also proportioned to have cement replacement with Class C fly ash in the range of 0-70% by weight. Each concrete mixture was tested for compressive strength, air permeability, water permeability, and chloride ion permeability. Air and water permeabilities were evaluated by using the Figg method. Chloride ion permeability was measured in accordance with ASTM C 1202. Air permeability of plain portland cement concrete was lower than that for concrete containing fly ash at the age of 14 and 28 d. At the age of 91 d, the 55% fly ash mixture exhibited the highest resistance to air permeability. All the concrete mixtures showed "fair" resistance to water permeability at ages up to about 40 d. 11le maximum resistance to water permeability was observed for the 35% fly ash mixture at ages of 28 and 91 d. At the 2 month age, chloride ion permeability of all mixtures except the 74% fly ash mixture were rated as "mod­ erate" to "very low" in accordance with ASTM C 1202 criteria. When duration of curing was increased to three months, the fly ash concrete mixtures with fly ash to cementitious materials in the range of 18-55% showed lower chloride ion per­ meability than the concrete without fly ash. 11le same trend was observed at the age of I yr.
Boosting Children’s Persistence through Scientific Storybook Reading

ABSTRACT Eighty-six 4- and 5-year-old children were assigned to one of four conditions, three experimental conditions, in which children read a story about a famous scientist, and one baseline condition. In the Achievement condition: the scientist was described as receiving awards and recognition through their lifetime, with no discussion of setbacks; in the Intellectual Struggles, the scientist was described as making mistakes along the way to success; and in the Life Struggles, the book emphasized personal struggles, such as having no money for food. In the Baseline condition, children completed a persistence task without having first read the story. In each experimental condition, children were asked 12 questions adapted from the Dimension of Mastery Questionnaire-18, which examined their persistence and motivation when faced with a challenging task. Finally, children were presented with the persistence task. Analyses revealed that children in the Intellectual Struggles and Life Struggles conditions persisted longer on the task than children in the Achievement Condition. These findings suggest that storybooks that emphasize the process of science, rather than solely focusing on achievement can impact persistence as well as feelings of relatedness in STEM.
Testing the consequences of alcohol, cannabis, and nicotine use on hippocampal volume: a quasi-experimental cotwin control analysis of young adult twins

Abstract Background Alcohol, cannabis, and nicotine use are highly comorbid and alarmingly prevalent in young adults. The hippocampus may be particularly sensitive to substance exposure. This remains largely untested in humans and familial risk may confound exposure effects. We extend prior work on alcohol and hippocampal volume in women by testing common and unique substance use effects and the potential moderating role of sex on hippocampal volume during emerging adulthood. A quasi-experimental cotwin control (CTC) design was used to separate familial risk from exposure consequences. Methods In a population-based sample of 435 24-year-old same-sex twins (58% women), dimensional measures (e.g. frequency, amount) of alcohol, cannabis, and nicotine use across emerging adulthood were assessed. Hippocampal volume was assessed using MRI. Results Greater substance use was significantly associated with lower hippocampal volume for women but not men. The same pattern was observed for alcohol, cannabis, and nicotine. CTC analyses provided evidence that hippocampal effects likely reflected familial risk and the consequence of substance use in general and alcohol and nicotine in particular; cannabis effects were in the expected direction but not significant. Within-pair mediation analyses suggested that the effect of alcohol use on the hippocampus may reflect, in part, comorbid nicotine use. Conclusions The observed hippocampal volume deviations in women likely reflected substance-related premorbid familial risk and the consequences of smoking and, to a lesser degree, drinking. Findings contribute to a growing body of work suggesting heightened risk among women toward experiencing deleterious effects of substance exposure on the still-developing young adult hippocampus.
Business Cycle Implications of Firm Market Power in Labor and Product Markets

In this paper, we analyze the business cycle implications of firms having oligopsony power in labor markets, as well as oligopoly power in product markets, within the context of a New Keynesian dynamic stochastic general equilibrium model with firm entry and exit. Relative to the standard setup with monopolistic competition in both goods and labor markets, the strategic interaction between intermediate goods firms in the current setup results in larger price markups as well as wage markdowns, while the slopes of the aggregate price and wage Phillips curves become flatter. These effects are strengthened in a strongly non-linear fashion as the number of firms in each sector decline. Oligopsonistic labor markets also render wage shocks expansionary, unlike in the standard setup. Results indicate that a secular increase in industry concentration would not only reduce the labor share of income, but also weaken the pass-through from firms’ marginal costs to prices and from productivity increases to real wages.
Trade Networks in Latin America: Spatial Inefficiencies and Optimal Expansions

The Policy Research Working Paper Series disseminates the findings of work in progress to encourage the exchange of ideas about development issues. An objective of the series is to get the findings out quickly, even if the presentations are less than fully polished. The papers carry the names of the authors and should be cited accordingly. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the International Bank for Reconstruction and Development/World Bank and its affiliated organizations, or those of the Executive Directors of the World Bank or the governments they represent.
Behavioral and Emotional Reactions of the Russian Population to the Beginning of the COVID-19 Pandemic: An On-Line Survey Results.

BACKGROUND The study aimed to identify the patterns of adaptive and behavioral strategies in different population groups, also to evaluate their association with the infection prevention strategies and the distress during the COVID-19 pandemic. METHODS The data were obtained from the on-line survey of 1958 respondents (mean age 31±12 years) from March 30, 2020 to April 5, 2020. 578 respondents reported a history of affective disorders; 884 respondents - a history of somatic disease. The level of anxiety distress was evaluated with the Psychological Stress Measure (PSM-25). The analysis of variance was used for statistics. p<0.05 was considered significant. The effect sizes (ES) were evaluated according to Cohen's d and Cramer's V criteria. RESULTS The average PSM-25 score corresponded to moderate stress intensity. An increased level of psychological stress was associated with the young age of the respondents, the history of affective disorders and somatic diseases, the compliance with self-isolation, the practice of social distancing, and the use of sanitizer. Concerns about the availability of protective equipment were specifically associated with the self-isolation compliance (ES=0.1); the combination of concerns about the contagiousness of the virus (ES=0.12) and the inaccessibility of daily medications (ES=0.11) - with the principles of social distance. Moreover, the concerns about the lack of specific treatment, the danger to one's own life, the contagiousness of the virus, and the lack of protective equipment were associated with the protective behavior resulting in increased hand hygiene. The history of affective disorders was rarely associated with wearing masks and gloves, but more often - with the use of self-isolation strategies. CONCLUSIONS The psychological reactions of the population during the COVID-19 pandemic are specifically associated with adaptive behavior in the process of anti-epidemic measures. Respondents with affective disorders experienced specific patterns of anxiety about coronavirus infection in combination with high rates of psychological stress.
Estimation of Vertical Fuel Layers in Tree Crowns Using High Density LiDAR Data

The accurate prediction and mitigation of wildfire behaviour relies on accurate estimations of forest canopy fuels. New techniques to collect LiDAR point clouds from remotely piloted aerial systems (RPAS) allow for the prediction of forest fuels at extremely fine scales. This study uses a new method to examine the ability of such point clouds to characterize the vertical arrangement and volume of crown fuels from within individual trees. This method uses the density and vertical arrangement of LiDAR points to automatically extract and measure the dimensions of each cluster of vertical fuel. The amount and dimensions of these extracted clusters were compared against manually measured clusters that were collected through the manual measurement of over 100 trees. This validation dataset was composed of manual point cloud measurements for all portions of living crown fuel for each tree. The point clouds used for this were ground-based LiDAR point clouds that were ~80 times denser than the RPAS LiDAR point clouds. Over 96% of the extracted clusters were successfully matched to a manually measured cluster, representing ~97% of the extracted volume. A smaller percentage of the manually measured clusters (~79%) were matched to an extracted cluster, although these represented ~99% of the total measured volume. The vertical arrangement and dimensions of the matched clusters corresponded strongly to one another, although the automated method generally overpredicted each cluster’s lower boundary. Tree-level volumes and crown width were, respectively, predicted with R-squared values of 0.9111 and 0.7984 and RMSE values of 44.36 m2 and 0.53 m. Weaker relationships were observed for tree-level metrics that relied on the extraction of lower crown features (live crown length, live crown base height, lowest live branch height). These metrics were predicted with R-squared values of 0.5568, 0.3120, and 0.2011 and RMSE values of 3.53 m, 3.55 m, and 3.66 m. Overall, this study highlights strengths and weaknesses of the developed method and the utility of RPAS LiDAR point clouds relative to ground-based point clouds.