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In pulp and paper the modelling and simulation of the pulp production processes was the first major application. Since then several other applications have been realised though papermaking has never been on the lead concerning the use of computer-based modelling and simulation. The complex nature of the materials is one of the most demanding challenges and the biggest hurdle for any electronic description of the papermaking process or paper itself. So other industries took the lead and it is now for the paper industry to learn from these industries what can be done with the help of computers to control or optimise processes or to design new grades. The application of results gained with the use of modelling and simulation techniques in pulp and paper manufacturing processes has helped the industry to, for example, reduce emissions and increase the productivity and cost-efficiency of the processes. Still there are many important tasks open. A better understanding of the mechanisms of the processes and their control loops has to be achieved in order to further improve the paper quality, stabilise the wet-end chemistry, and enhance the runnability. Important features to be developed are new process designs, efficient process monitoring and systems that offer decision support during operation. In this paper a review of the state of the art on modelling and simulation in the pulp and paper industry is presented as well as further research needs. [ABSTRACT FROM AUTHOR]

Operations Research (OR) is a branch of applied mathematics that deals with optimization problems arising from different real contexts. The solving process of its problems is based on the construction and resolution of mathematical models, showing the possible connections between mathematics and the real world. Nevertheless, OR is not typically included in most curricula of higher secondary schools (i.e. Grades 9–12), but it is usually presented mainly at university level. To show how OR could be significant for these school students' education, the authors of this paper developed an educational project consisting of three teaching units. In this paper, we share the result of the teaching experiment related to the first unit, addressed to Grade 10. Qualitative and quantitative analyses show how it is appropriate to include OR and its typology of problems in regular school mathematics lectures. Second, these data also show how modelling and problem-solving skills, developed working with OR, can be fostered by implementing a collaborative way of working, also by making use of digital technologies. Last but not least, we demonstrate the positive impact such activities have on students' appreciation of OR. [ABSTRACT FROM AUTHOR]

Migration due to indirect contact with packaging caused several major sanitary crises, including the spread contamination of dry food by mineral oils and printing ink constituents from cardboard. The issues are still not fully resolved because the mechanisms have been insufficiently described and the relationship between design, contamination level, type of contaminant, and conditions of storage (time and temperature) are poorly understood. This study proposes a forensic analysis of these phenomena when food is separated from cardboard by a plastic layer. Practical relationships and advanced simulation scenarios were devised and validated against the long-term migration between 20 and 60°C of 15 substances. They were chosen to be representative of the main contaminants of cardboard: aliphatic and aromatic mineral oils, photo-initiators and plasticisers. Data were summarised as iso-contamination curves and iso-contamination times up to 2 years. Simple rules are illustrated to extrapolate the results to arbitrary conditions in order to identify critical substances and to estimate the plastic film’s thickness to keep the contamination within acceptable limits. Recommendations for the risk management of contamination routes without contact are finally drafted. [ABSTRACT FROM AUTHOR]

Papermaking is an industrial process that is becoming more competitive nowadays. In this process there are numerous techniques and measurements to indicate paper quality. To increase competitiveness a good control of paper quality is needed through paper properties predictions from different process measurements. However, complex physico-chemical processes take place during papermaking, and thus, paper property predictions are not easy to obtain, especially in the wet-end area. In the wet end flocculation takes place, which will determine the floc properties during the formation of the sheet, and therefore, it will influence retention, drainage and formation. These strongly affect the runnability of the machine and the properties of the final product, and thus, using wet-end measurements for the predictions implies advanced data treatment. Artificial neural networks have been used in this article to predict newsprint paper properties from wet-end parameters. Results show that formation and strength properties can be robustly predicted from pulp properties at the headbox, flocculation parameters and machine speed. [ABSTRACT FROM AUTHOR]

This study presents an inquiry into the relevance of Bildung for students in (pre-) vocational education. While Bildung has seen a remarkable revival in international educational theory, its relevance for educational practice(s) remains under-investigated, particularly in vocational education. This paper presents the insights offered by a multi-method curriculum study, conducted as part of a larger project in which (pre)vocational teachers in the Netherlands experimented with their own role as a model of and for their students' Bildung. Building on a thematic analysis of teacher observations, teacher interviews and student focus groups, we explore how six teachers enacted and perceived their modelling role, and how their students experienced it. While all teachers modelled elements of what they found important for their students' Bildung, the teachers actually perceived as models of Bildung by their students were those who shared their own experiences and stories with students, and who related to them on a personal level by offering them support, trust and inspiration to pave their own paths in life. Based on our findings, we suggest implications for broadening common understandings of Bildung and modelling, as well as practical implications for teachers, teacher education and policy to foster vocational students' Bildung. [ABSTRACT FROM AUTHOR]

Because of the gradual depletion of gravel and river sand resources and restrictions on quarrying activities to maintain the ecological balance, limestone crushed sand with a high content of limestone fillers is being explored to be used, as an alternative source of supply, in Portland cement concrete (PCC) for rigid pavement. This paper aims to first present mechanical test results carried out on three types of PCC formulated with crushed limestone sand as fine aggregates, devoid of superplasticizers. Since shrinkage cracking is an important problem for rigid pavement, the shrinkage behaviour of these concretes is then experimentally investigated. Furthermore, three existing models (ACI-209, Eurocode2, and triple-sphere models) and a novel-developed model are used to estimate the mixtures' shrinkage. Results showed that the designed mixtures exhibited normal shrinkage values. The shrinkage modelling revealed that the proposed model well fitted the experimental data. Besides, Eurocode2 and ACI-209 models may be adapted for the case of limestone concretes containing a high content of limestone fillers and then used to accurately estimate their shrinkage strains. However, the triple-sphere model was unsuitable for these concretes and overestimated their ultimate shrinkage since it does not take into account their high filler content. Nevertheless, by adjusting the paste shrinkage expression, the ultimate shrinkage strain values of the tested mixtures were improved. [ABSTRACT FROM AUTHOR]

Machine learning approaches are increasingly being adopted as data analysis tools in scientific behavioral predictions. This paper utilizes a machine learning approach, Random Forest Model, to determine the top prediction variables of food safety behavioral changes during the pandemic. Data was collected among U.S. consumers on risk perception of COVID-19 and foodborne illness (FBI), food safety practice behaviors and demographics through online surveys at ten different time points from April 2020 through to May 2021; and post pandemic in May 2022. Random forest model was used to predict 14 food safety-related behaviors. The models for predicting Handwashing before cooking and Handwashing after eating had a good performance, with F-1 score of 0.93 and 0.88, respectively. Attitudes- related variables were determined to be important in predicting food safety behaviors. The importance ranking of the predicting variables were found to be changing over time. [ABSTRACT FROM AUTHOR]

The central question of this paper is whether and how, from a virtue ethical perspective, teacher modelling and student emulation hang together in moral education. This matters, because philosophers have often focussed either on the moral psychology of emulation or on modelling as a moral educational method, neglecting the interplay between the two. It starts by analysing the conceptual framework underlying the influential Manner in Teaching (MiT) and Moral Work of Teaching (MWT) projects. It reconstructs how modelling is understood as ‘teaching morally’ or ‘teaching morality’. These two interpretations of modelling are developed further by drawing on additional literature on teacher education and moral education. Then, the conceptual framework is extended by focusing on how students may learn from modelling through mimicry, imitation or emulation. This results in several conceptual relations that illuminate the complex dynamics between teacher modelling and student emulation. For example, teacher modelling does not guarantee student emulation, which challenges the common advocacy for teachers as role models. At the same time, students may emulate teachers without teachers being aware of their impact. This results in a more nuanced understanding of what it takes for teachers to be moral role models. [ABSTRACT FROM AUTHOR]

The availability of overhead views of the environments around mobile robots always present useful information provided that these views are correctly perceived. In this paper, a novel approach for vision-based path planning and obstacle avoidance for mobile robots is presented. The approach uses visual perception integrated with a proposed field-based path-planning algorithm to overcome some common path-planning issues such as local minima, problematic destinations, and following long paths around obstacles. An exponential angle field is generated around each obstacle that deviates from the robot’s orientation as it directs towards the destination. Obstacle field is activated or deactivated based on a proposed collision prediction algorithm. To satisfy robot convergence to the goal point, the obstacle field parameters are determined using the Lyapunov stability criterion. The method also proposes a search algorithm for proper exit in the case of robot and/or goal point trapping. Both simulation and experiments are used in validating the algorithm. The results show the effectiveness of the proposed algorithm in converging towards target points, avoiding collision with stationary obstacles and overcoming famous path-planning problems. [ABSTRACT FROM AUTHOR]

This paper aims to offer a new perspective on role modelling by examining adolescents' own efforts to lead a morally virtuous life. While traditional approaches to moral education emphasize the importance of teachers as role models, this study proposes a shift in focus towards adolescents' own role models. Drawing on the philosophical concept of moral self-cultivation and psychological insights on identity development and social cognitive learning, it is argued that adolescents have the ability to cultivate their moral character by emulating others. However, empirical evidence suggests that adolescents often do not perceive teachers as their role models. Consequently, moral educational theories are advised to demand less of teachers as role models. Teachers could invest more time in understanding students' personal role models and encourage them to compare these role models with their own behavior. By acknowledging and addressing students' role models, teachers can facilitate the moral self-cultivation of adolescents. [ABSTRACT FROM AUTHOR]

Students exit calculus with understandings of change that want for conceptual depth and are disconnected from real-world contexts. In this paper, we present a problem that will develop their skills in using change concepts for learning differential equations through modelling. The problem comes from a qualitative study of how STEM majors approach and think about differential equations as models for real-world scenarios. Our purpose is to inform faculty who are using open, authentic, scenario-driven instructional materials about the ways their students think about what are often taken-for-granted concepts in advanced mathematics and to support faculty in ensuring their students get the most from their innovative instructional materials. [ABSTRACT FROM AUTHOR]

After waiting in a long line for your favourite cup of coffee, you finally sit down with your mug and find that the coffee is still scalding hot! How long do you need to wait before you can enjoy it? Once it cools enough, how much time do you have to enjoy it? Are there ways to speed up the process? These questions motivate the presented modelling scenario about tracking the temperature of a cup of coffee as it cools. Students are put in the role of an inquisitive coffee enthusiast who does their due diligence in preventing burns and carefully experimenting on their coffee so that they, and others to come, can enjoy that perfect cup. They identify their assumptions and interventions before developing model differential equations for each case, which force discontinuities on the derivative and even on the solution itself. Being familiar with basic Laplace transforms and learning key properties of the unit step and unit impulse functions, they solve these differential equations and compare the interval of time when the coffee will be at its peak level of enjoyment. This paper includes an implementation guide, grading rubric, example solutions, and example assessment questions. [ABSTRACT FROM AUTHOR]

Lidar data have been regarded as the most important data source for accurate forest biomass estimation. Different platforms such as terrestrial Laser scanning, unmanned aerial vehicle Laser scanning, airborne Laser scanning, and spaceborne Lidar (e.g. ICESat-1/2, GEDI, GF-7 Lidar) provide new opportunities to map forest biomass distribution at different scales. The ground-based Lidar data are mainly used for extracting individual tree parameters such as diameter at breast height (DBH) and tree height, attempting to replace or reduce field work, while spaceborne Lidar data are often used to extract canopy height data at national and global scales, but cannot provide wall-to-wall mapping. The airborne Lidar may be the most frequently used data for forest biomass estimation at local scale. Many studies have been conducted for mapping forest biomass distributions in different climate zones, but current research situations and challenges of using airborne Lidar data have not been fully overviewed. This paper attempts to provide an overview of using airborne Lidar data for forest biomass estimation and discuss current research problems and future directions, which will be valuable for professionals and practitioners to better understand the important role of using airborne Lidar data for forest biomass estimation at the local scale. [ABSTRACT FROM AUTHOR]

MWCNTs and ultra-fine steel microwires double-doped RPC are researched to determine the modification law of flexural strength and post-folding compressive strength in order to investigate the impact of nanoscale admixtures on the strength of high-rise building concrete. This research also examines the elastic modulus of the prismatic specimen as well as the flexural toughness and compressive toughness of the load-displacement curve. Through theoretical calculations of composite materials, this paper also investigates how MWCNTs and ultra-fine steel microwires double-doped fillers improve the mechanical properties of RPC. Additionally, this work uses experimental techniques for material preparation, performance analysis and simulation research in conjunction with intelligent models. The method suggested in this research has a certain effect, and has a certain promotion effect on the subsequent performance improvement of concrete materials, as can be observed from the data statistics. [ABSTRACT FROM AUTHOR]

Moringa oleifera utilization in water treatment to eliminate emerging pollutants such as heavy metal ions, pesticides, pharmaceuticals, and pigments has been extensively evaluated. The efficacy of Moringa oleifera biosorbent has been investigated in diverse research work using various techniques, including its adsorption capacity kinetic, thermodynamic evaluation, adsorbent modifications, and mechanism behind the adsorption process. The Langmuir isotherm provided the most remarkable experimental data fit for batch adsorption investigations, whereas the best fit was obtained with the pseudo-second order kinetic model. Furthermore, only a few papers that combined batch adsorption with fixed-bed column investigations were examined. In the latter articles, the scientists modified the adsorbent to increase the material's adsorption capacity as determined by analytical methods, including IR spectroscopy, scanning electronic microscope (SEM), and X-ray diffraction (XRD). However, the raw material can show appreciable adsorption capacity values, proving moringa's potency as a biosorbent. Hydrogen bonds, electrostatic interaction, and van der Waals forces were the main processes in the found and reported adsorbent-adsorbate interactions. These mechanisms could change depending on the physiochemical nature of adsorption. Although frequently employed for heavy metal ions and dye adsorption, Moringa oleifera can still be explored in pesticide and medication adsorption investigations due to the few publications in this comprehensive review. This study, therefore, examined different Adsorbents from the Moringa oleifera plant, as well as parameters and models for enhancing the adsorption process. [ABSTRACT FROM AUTHOR]

This paper studies the potential effects of Reclaimed Asphalt Pavement (RAP) fine particles on bituminous mixtures by means of a laboratory investigation performed at the mastic scale. Bituminous mastics, characterised by a constant filler to bitumen volume ratio, were prepared by combining virgin filler and virgin bitumen with several dosages of RAP fine particles. The influence of RAP type was evaluated by employing two RAP products supplied by different sources. The rheological behaviour of the mastics was investigated by means of oscillatory tests carried out with a dynamic shear rheometer. The time-temperature superposition principle and the generalised self-consistent scheme (GSCS) micromechanical model were used to explore the role played by RAP at the mastic scale. Results indicate that the adopted experimental and modelling approach allows a proper assessment of the effects of RAP on the linear viscoelastic properties of mastics and of the degree of blending occurring between virgin and RAP binder. [ABSTRACT FROM AUTHOR]

This paper studies the potential effects of Reclaimed Asphalt Pavement (RAP) fine particles on bituminous mixtures by means of a laboratory investigation performed at the mastic scale. Bituminous mastics, characterised by a constant filler to bitumen volume ratio, were prepared by combining virgin filler and virgin bitumen with several dosages of RAP fine particles. The influence of RAP type was evaluated by employing two RAP products supplied by different sources. The rheological behaviour of the mastics was investigated by means of oscillatory tests carried out with a dynamic shear rheometer. The time-temperature superposition principle and the generalised self-consistent scheme (GSCS) micromechanical model were used to explore the role played by RAP at the mastic scale. Results indicate that the adopted experimental and modelling approach allows a proper assessment of the effects of RAP on the linear viscoelastic properties of mastics and of the degree of blending occurring between virgin and RAP binder. [ABSTRACT FROM AUTHOR]

Gilboa, Postlewaite, Samuelson and Schmeidler (2022, Economic theories and their dueling interpretations. Journal of Economic Methodology, 1–20. https://doi.org/10.1080/1350178X.2022.2142270; henceforth GPSS) give a ‘sociological’ account of various ways in which economists claim to find value in ‘analytical’ models – i.e. models that investigate formal relationships between concepts without deriving substantive empirical or normative conclusions. In this paper, I argue that some of the claims that GPSS report economists as making are defensible, but that others are used in support of modelling strategies that have little or no scientific value. [ABSTRACT FROM AUTHOR]

This study aims to determine the impact of Industry 4.0 innovations, namely infographics and product modelling, on students’ academic performance and visual thinking skills. The experiment involved 164 students. Teaching tools promote the student’s academic performance and visual thinking. The average grade of academic performance was higher in the experimental group (15.70) than in the control group (13.73) after testing. The statistical analysis (t = 2.620) provided evidence supporting the research hypothesis that students who utilised infographics and modelling exhibited significantly enhanced visual thinking skills compared to the students in the control group. These studies allow the development of a paradigm of infographics for further understanding of its capabilities in the process of education. Subsequent scientific papers may study the influence of infographics and modelling on students of other professional fields. It is also necessary to study their influence on other mental parameters, such as cognitive load, motivation, involvement, and others. [ABSTRACT FROM AUTHOR]

The present paper is concerned with the investigation of the inelastic behaviour observed in load-unload cyclic tests performed at 50°C in single lap joints composed of a polyurethane based composite reinforced with fibreglass bonded to an ASTM A1020 steel substrate using an epoxy adhesive. The experiments presented in this research show that the inelastic behaviour of the joint is strongly dependent on the load frequency, eventually leading the structure to exhibit a progressive deformation when submitted to load-unload cyclic loading. The main goal of this study was to propose a preliminary rate-dependent mechanical model capable to describe the cyclic inelastic behaviour for an arbitrary load-unload history at low frequencies and a reasonable agreement was obtained between the experimental results and the model predictions. [ABSTRACT FROM AUTHOR]

This paper presents a comparison between the black box Nonlinear Auto-Regressive with eXogenous inputs-Neural Network (NARX-NN) and the conceptual Hydrologic Engineering Centre-Hydrologic Modelling System (HEC-HMS) Rainfall-Runoff models. The two models were applied on a small urban watershed to assess its response to fourteen hourly real storm events. The differences between the steps engaged in each model to reach the hydrograph were presented in detail. The estimation of the best parameters is carried out using a weighted average function during the calibration phase. A statistical evaluation was conducted to assess the model's performance thereafter; a critical comparison was made to illustrate the differences and discuss the steps involved. The results indicate that both models successfully reflect the urban basin runoff. However, the NARX-NN outperforms in the testing phase owing to their strength generalization feature. The NARX-NN model has more strength to produce the shape bending of the hydrograph. Consequently, this model is better to highlight the curvatures resulting from the local peaks of rainfall. [ABSTRACT FROM AUTHOR]

In this paper, a statistical model for COVID-19 infection dynamics is described, using only the observed daily statistics of infected individuals. For this purpose, two special classes of branching processes without or with an immigration component are considered. These models are intended to estimate the main parameter of the infection and to give a prediction of the mean value of the non-observed population of the infected individuals. This is a serious advantage in comparison with other more complicated models where the officially reported data are not sufficient for estimation of the model parameters. The model is applied for different regions in the world and the corresponding parameters of the infection dynamics are estimated. [ABSTRACT FROM AUTHOR]

National uniform legislation exists in federations to implement national reforms where the central government does not have the direct authority to legislate under the Constitution. The State jurisdictions must work together on legislation to address urgent issues of national concern, national uniform legislation. Developing and drafting national uniform legislation are complicated and complex because they require the cooperation of many units with asymmetrical knowledge, competing priorities, limited budgets and timeframes, and at times irreconcilable differences. Empirical data analysis and statistics could provide an aid for decision-making in these circumstances. On examination of a large body of legal information on the 69 most significant Australian national reforms, this article finds factors that inhibit or promote sustainable uniformity of enacted legislation by using ordinal regression for the first time. This work provides significant evidence-based insights into the process of harmonisation in federations. Overall, our findings contradict the general belief that the uniformity is mostly dependent on structures alone (referred, applied, mirror, and hybrid). If sustainable uniformity is the goal,the decision-makers must allow resources for establishing the national regulator, ensure maximum uptake by the majority of the nine Australian jurisdictions, support the development of national uniform legislation through the National Cabinet, and be prepared for the second wave of national reforms through consecutive reforms. These findings have valuable strategic implications for policymakers, law reform agencies, and legislative drafters who intend to rely on evidence for future decision-making in terms of the most important national reforms. This paper provides recommendations for governments intending to ensure the sustainability of uniformity and adaptability of the Australian legislation for any future changes without losing the important consensus that has been achieved. The findings are also important for other federations seeking to implement harmonised legislation. [ABSTRACT FROM AUTHOR]

In this paper, we analyse the model of pure carving turns in alpine skiing and snowboarding based on the usual assumption of approximate balance between forces and torques acting on the skier during the turn. The approximation of torque balance yields both lower and upper limits on the skier speed, which depend only on the sidecut radius of skis and the slope gradient. We use the model to simulate carving runs on slopes of constant gradient and find that pure carving is possible only on slopes of relatively small gradient, with the critical slope angle in the range of 8 ∘ − 20 ∘ . The exact value depends mostly on the coefficient of snow friction and to a lesser degree on the sidecut radius of skis. Comparison with the practice of ski racing shows that the upper speed limit and the related upper limit on the slope gradient set by the model are too restrictive and so must be the assumption of torque balance used in the model. A more advanced theory is needed. [ABSTRACT FROM AUTHOR]

Solar power provides a great promise and hope to minimize the gap between energy requirement and delivery and availability as well. The simultaneous energy demand in connection with the depleting predictable power sources requires the efficient use of the inexhaustible energy resources. The green property and inexhaustibility are the two basic properties inherited naturally to solar energy make it most suitable to get the maximum of it. The solar energy has significantly increased its share recently both in rural and urban regions in the form of solar farming and building installations. The energy so far harnessed from the sun radiations has been proved to be a proficient elucidation to the world's power aspirations. It becomes paramount to acquire absolute knowledge and precise comprehension of various aspects dealing with solar energy. The paper is compilation of a complete narrative reassess and guesstimation of the solar energy harnessing techniques such as MPPT, econometrics, equations for finding angles, temperature of the cell and forecasting methodologies that are being discussed. Among the accessible previous and latest available methods a few of them notably have been projected and presented with their appropriate flowcharts, block diagrams and algorithms. The paper is valuable for a researcher to opt any of these proposed methodologies, equations depending upon his necessity, constraints, relevance and concern as well. [ABSTRACT FROM AUTHOR]

This paper proposes a mathematical model approach to predict the Ultrasonic Pulse Velocity (UPV) of concrete. This paper presents the formulation, calibration, evaluation, and validation of the proposed UPV model. An experimental program was developed to calibrate and evaluate the proposed model. Furthermore, the model was validated using a separate group of measurements in the experimental program, to test its accuracy and generalization capability. Analysis of the results reveals that the proposed model provides a good fit to the experimental data and does not contain outliers or discerning pattern. The corresponding standard error and determination coefficient are 45 m/s and 0.92, respectively. Model validation demonstrates high predictability and generalization capability. The corresponding standard error and determination coefficient are 74 m/s and 0.91, respectively. [ABSTRACT FROM AUTHOR]

Landfill gas generated from waste degradation comprises a significant fraction of methane. Methane emission modelling is of utmost importance for sizing landfill methane collection system and for assessing viability of waste to energy projects. This paper reviews all the methane emission models developed till date and identifies their drawbacks. This paper will assist in developing a more accurate methane emission model for waste to energy projects. [ABSTRACT FROM AUTHOR]

Cohesive soil was often submitted to the shrinkage when it is dried. Constrained shrinkage and heterogeneity of the soil in terms of density or porosity and water content conduct to cracks of the fine soil. The unsaturated permeability as a function of suction changes significantly with cracks number and opening. The paper aims to study the flow exchange flow in the unsaturated cracked clay flow, by measurement of the unsaturated permeability using tensiometer and hygrometer sensors in cracked specimens under drying and controlled in an environmental chamber. The instantaneous profile method was used to interpret these tests. Cracks were characterised by Image Analysis which conducted to define some known quantitative parameters as the Cracks Intensity Factor (CIF). Aiming at reproducing the experimental results, the paper presents a model which leads to the prediction of the suction field and the flow rate exchange. This model integrates analytical equations of the unsaturated permeability and water retention property of the cracked soil and also the shrinkage behaviour. A good agreement between numerical and experimental results is highlighted in terms of flow exchange rate. [ABSTRACT FROM AUTHOR]

Modelling source water quality in drinking water treatment systems could be useful for anticipating changes in specific raw water quality parameters. Those changes entail adjustments in drinking water treatment plant (DWTP) operations. Artificial intelligence (AI) has been used for modelling water quality for different purposes and has yielded reliable results. However, there has not yet been wide investigation of raw water quality modelling for treatment purposes using AI. For the first time, in this critical review, we analyzed AI models founded on machine learning techniques that are used for surface water quality modelling and which could be applied in the domain of source water treatment. In a novel approach, we convened an expert panel that helped us define the appropriate criteria for use in the selection of the papers for review. We analysed the selected papers according to several criteria, including the feasibility of input data generation, the modelled data applicability and the benefits and limitations. We evaluated whether the selected models could be applied to forecast raw water quality as decision support systems (DSS) in drinking water treatment. The highest rated were turbidity hourly models based on Support Vector Machines (SVM), as well as daily turbidity and pH models based on Artificial Neural Networks (ANN). We found there is a shortage of models used to specifically estimate raw water quality, which could assist in DSS at DWTPs. There should be an increased effort to model raw water quality, especially with AI models using hourly and sub-hourly time step. [ABSTRACT FROM AUTHOR]

The paper proposes a spreadsheet-based model to simulate the hydrological response of a pilot installation of modular tray-based blue roof (BR). The BR is installed on the roof terrace of a building in the Campus of the University of Catania (Italy). The paper firstly describes the results of preliminary field experiments on the pilot aimed at evaluating hydrological parameters used in the model, i.e. the runoff coefficient and the initial abstraction of the terrace, and the evaporation from the BR. Then, the model was applied to 26 precipitation events recorded in the period from 2018 to 2020. Results of the application show a good ability of the model to reproduce the hydrological behaviour of the BR during precipitation events. Finally, the paper discusses limitations of the results obtained and potential for model improvement. [ABSTRACT FROM AUTHOR]

Estimation of bicycling volumes is essential for the strategic implementation of infrastructure and related transport elements and policies. Link-level volume estimation models (models that estimate volumes on individual street segments) allow for understanding variation in bicycling volumes across an entire network at higher spatial resolution than area-level models. Such models assist transport planners to efficiently monitor network usage, to identify opportunities to enhance safety and to evaluate the impact of policy and infrastructure interventions. However, given the sparsity and scarcity of bicycling data as compared to its motorised counterparts, link-level bicycling volume estimation literature is relatively limited. This paper conducts a scoping review of link-level bicycling volume estimation methods by implementing systematic search strategies across relevant databases, thereby identifying appropriate studies for the review. The review resulted in some interesting findings. Among all the methods implemented, direct demand modelling was the predominant one. Not a single study implemented multiple modelling approaches in the same study area, thereby not allowing for comparison of these approaches. Most studies were conducted in the United States. It was also observed that there exists a lot of heterogeneity in the reporting of basic study characteristics and validation results, sometimes to the extent of not reporting these at all. The study presents the different types of data used in modelling (count, travel survey, GPS data) along with an array of popular explanatory variables that can inform future studies about data collection and variable selection for modelling. The study discusses the strengths and limitations of different methods and finally presents recommendations for future research. [ABSTRACT FROM AUTHOR]

This paper surveys flood mapping and modelling in Nigeria in regard to frequency and impact of floods in the last decade. The aim is to understand the frequency and patterns of flooding and approaches to its modelling in relation to current practices globally. The northern part of Nigeria is affected more by flooding than the south, so should be prioritised for flood management. The use of remote sensing data with GIS techniques is the most common approach to flood modelling in Nigeria. Bayesian and machine learning approaches should be used, in preference to process-based models. [ABSTRACT FROM AUTHOR]

This paper is concerned with the repair of through-wall corrosion damage in metallic pipes using bonded metallic patches. The focus is on the analysis of the influence of the thickness of the patch on the effectiveness of the repair. The goal is to assure that the pipe won't leak once the repair is completed. Usually, in practical applications, a composite sleeve is used combined with a metallic patch. The study shows that only a bonded metallic patch can be sufficient to avoid leaking (no composite sleeve is necessary), but the effectiveness of the repair is strongly dependent on its thickness. Experimental results show that the failure pressure using patches with the same area but with different thicknesses can be very different. Burst tests were performed on API 5 L grB steel hydrostatic specimens with a 25 mm hole repaired with 100 mm × 100 mm patches. Depending on the thickness, the failure pressure can vary from 70 to 270 bar. A model based on the Linear Elastic Fracture Mechanics is proposed to obtain an estimate of the failure pressure using only one algebraic equation. The experimental results are in good agreement with model predictions. [ABSTRACT FROM AUTHOR]

This letter addresses high-resolution sea clutter modelling. Radar clutter modelling is essential to develop constant false alarm rate (CFAR) detection schemes. In this paper, we propose a compound model by the use of the inverted exponentiated Rayleigh (IER) distribution as texture component. The probability density function (PDF) of the compound inverted exponentiated Rayleigh (CIER) distribution is a function of three parameters including the thermal noise power. To assess the modelling performance of the CIER distribution, several tests have been performed using the Intelligent PIXel Processing Radar (IPIX) database where the fitted PDFs and the complimentary cumulative density functions (CCDFs) of the CIER, the well-known compound K and the compound inverse Gaussian (CIG) distributions are compared with the real PDF and CCDF. The results obtained validate the ability of the CIER distribution to model high-resolution sea clutter. [ABSTRACT FROM AUTHOR]

To increase students' sense of ownership, the present study incorporated elements of Challenge-based learning (CBL) into a mechanical engineering course. CBL is a desirable pedagogy adopted by many universities of technology. Although the boundaries and constraints of a regular course hinder the application of CBL, some of its benefits can be retained. In this paper, we investigate a second-year mechanical engineering course which aimed to give students autonomy in choosing their modelling projects, to facilitate students' ownership of their learning processes. The mixed-methods analysis of the intervention reveals no particular benefits of the intervention on pilot students' ownership, compared to a control group. The qualitative analysis suggests that implicit and explicit factors constrain ownership development, namely the anticipated difficulty level and official constraints for selecting projects. Our findings suggest that, currently, there could be too simple assumptions about how providing students with autonomy in selecting their projects allows for student ownership. [ABSTRACT FROM AUTHOR]

Characterising spatial variability, which is of utter importance in inspection and maintenance strategies, requires comprehensive spatially distributed databases. However, in real practice, spatially distributed inspection is costly and could damage the structure if a large number of destructive tests are carried out. Therefore, the first objective of this work is to propose a methodology to extract as much informations as possible from available spatially distributed databases, in order to characterise the spatial correlation. Moreover, a preventive maintenance strategy should be supported by deterioration models able to propagate uncertainty and spatial variability. Then, the second objective of the paper is to evaluate the ability of these models to propagate uncertainties and spatial variability. The methodology is illustrated with data collected through destructive tests in a concrete wall exposed to carbonation. The database encompasses information about the concrete porosity, saturation degree, density, and carbonation depth. Recommendations are hence provided in this work for the choice of input parameters that should be modelled as random fields. These recommendations were applied and then confirmed by comparing measured and modelled spatially distributed carbonation depths. The results highlight that uncertainties in measurements and statistical uncertainties have significant impact when dealing with spatial variability. [ABSTRACT FROM AUTHOR]

Software rejuvenation is a policy to counter the phenomenon of software ageing. However, how to implement software rejuvenation is still an important issue. In this paper, periodic impulse control is proposed as an effective tool to perform software rejuvenation and improve the availability of software system. First, we formulate the software rejuvenation system with periodic impulse by a group of coupled differential equations with impulsive action. Then the well-posedness of the system is demonstrated by using operator semigroup theory. At the end of the paper, numerical examples are shown to illustrate the dynamic behaviour of the system and the relationship between the system instantaneous availability and the impulsive indexes, including impulse interval and impulse strength, which yields that the system availability can be improved by adjusting the impulsive indexes. [ABSTRACT FROM AUTHOR]

This paper presents the outcome of a study on the effect of the machining conditions on some performance parameters during dry and hard boring of ASTM A304 low alloy steel round bar with tungsten-carbide insert using a 3-level factorial design of experiment-based response surface methodology. It involved modelling, prediction and optimisation of the performance parameters subject to constraints on variation of the machining conditions. Within the limits defined by levels of the machining, the performance parameters were randomly determined in 27 runs of boring experiments. These experiments, which were performed on a D360 x 1000HS excel lathe machine, serial no J320581, involved dry and hard boring of 27 ASTM A304 low alloy steel specimen work-pieces using tungsten-carbide inserts at different levels of low, medium and high as specified for the machining conditions. The data analysis was performed using Design Expert software version 9.0.6.2 to model, predict, and to obtain the optimal machining conditions, and the corresponding performance parameters. The study revealed the control factors to have varying effects on the response variables of which the prime factor is the cutting speed, for the tool wear and cutting temperature, and depth of cut, for the material removal rate. Hence, it is recommended that the obtained values of these factors should be adopted for optimal machining of the aforementioned material. [ABSTRACT FROM AUTHOR]

The modelling of semi-conductor elements in molecular electronics as an emerging technological field requires further development. Using circuit elements, a typical model is presented in this paper. Taking the advantage of this model, a pyridine derivative molecular diode is modelled and the theory behind the components of the molecule model is explained. Subsequently, the physical properties of the proposed pyridine derivative molecular diode, including the electric potential drop along the molecule, rectification ratio, diode current, power consumption, transmission spectrum, and electron density along the molecular diode, are investigated. Then, using the molecular diode model, the basic logic gates including AND, OR, NOT, and XOR gates are modelled and using the basic gate model, the modelling of basic reversible molecular logic gates including Feynman, Toffoli, BVF, and Peres gates are implemented. Moreover, a full adder is modelled using the two Peres gate model. [ABSTRACT FROM AUTHOR]

Texture-based informal settlement (IS) mapping has gained attention in urban remote sensing (RS) research. Numerous studies conducted on the use of texture analysis for IS mapping have investigated wide-ranging sensors, algorithms, scale, classifiers, feature selection methods, and other factors of interest. However, no study has systematically investigated key factors affecting texture-based classification processes. This paper presents a detailed synthesis of scientific progress in texture based IS mapping. Results revealed that grey level co-occurrence matrix was the most popularly used algorithm.Quickbird was the widely used sensor. The use of machine-learning classifiers, particularly, support vector machine and random forest yielded, comparatively, high accuracies (>80%). Interestingly, deep learning showed potential to advance IS identification. Multi-city comparison studies demonstrated need for texture features to be locally specific in order to allow transferability. Thus, integration of RS data and field survey statistics could be crucial in enhancing understanding of morphological variations for improved IS mapping. [ABSTRACT FROM AUTHOR]

Lateral flow immunoassay (LFIA), as a well-known point-of-care testing (POCT) technique, is of vital significance in a variety of application scenarios due to the advantages of convenience and high efficiency. With rapid development of computational intelligence (CI), algorithms have played an important role in enhancing LFIA performance, and it is necessary to summary how algorithms can assist LFIA improvement for providing experiences. However, most existing works on LFIA are from biochemical field which pay more attention to material and reagent. Therefore, in this paper, a systematical survey is proposed to review works on applying mathematical tools to promote LFIA development. Particularly, a novel two-level taxonomy is designed for a better inspection, including LFIA-oriented mathematical modelling, CI-assisted post-processing and quantification in LFIA, and each level is further subdivided for in-depth understanding. In addition, from a higher viewpoint, outlooks of jointly developing POCT with other state-of-the-art techniques are presented from perspectives of implementation principle, technical approach and algorithm application. Moreover, this survey aims to highlight that applying CI methods is competent for boosting POCT development, so as to raise attentions from more areas like information science, extend deeper researches and inspire more interdisciplinary works. [ABSTRACT FROM AUTHOR]

A CEN technical report has been drafted by working group WG59 CEN/TC54 on how to determine no- and negligible creep temperature limits to support EN 13445-3 (Unfired Pressure Vessels - Part 3: Design). Presently the standard assumes "rule-of-thumb" values for no-creep temperatures of ferritic and austenitic steels, 375°C and 425°C correspondingly. It is thought well known that the lower ferritic grades could be creeping below the limit temperature and creep strength enhanced ferritic steels may show significant creep at temperatures well beyond it. Similarly, austenitic steels; nickel and other alloys are likely to have an even wider range of limit temperatures. This paper describes the data assessments and test methods used to determine limit temperatures for a specific set of steels and comparisons are made to other standards and nuclear design codes. The new approaches promote iso-stress testing in the low temperature range and apply Wilshire equation assessments on historical data. [ABSTRACT FROM AUTHOR]

This paper aims to experimentally study the impact of waste glass powder (GP) as a partial cement replacement (up to 20%) with two different particle size distributions ((55 µm < GP-A < 135 µm) and (55 µm > GP-B)) on the compressive strength and Modulus of Elasticity (MOE) of concrete. The concrete mixes for GP-A considered in this study have water to binder ratio (w/b) of 0.49 and 0.57, whereas only a w/b ratio of 0.57 was considered for GP-B mixes. The experimental data obtained were used to develop different models to predict the elastic modulus of GP-modified concrete. The test results showed that the compressive strength and the MOE decreased with the increase of GP content. The size effect of GP as compared to w/b and GP content on compressive and MOE was relatively small. A nearly similar failure behaviour and peak strain were observed for all concrete mixes. The stiffness of the concrete decreases comparatively with an increase in the GP replacement level. Finally, the proposed MOE equations provide better predictions than the empirical models and practice codes considered in this study. They can be used in calculating the elastic modulus of GP-modified concrete. [ABSTRACT FROM AUTHOR]

In this paper, we present an advanced model of centrifugal pendulum where its length is allowed to vary during swinging. This modification accounts for flexion and extension of skier's legs when turning. We focus entirely on the case where the pendulum leg shortens near the vertical position, which corresponds to the most popular technique for the transition between carving turns in ski racing, and study the effect of this action on the kinematics and dynamics of these turns. In particular, we find that leg flexion on approach to the summit point is a very efficient way of preserving the contact between skis and snow. The up and down motion of the skier centre of mass can also have a strong effect of the peak ground reaction force experienced by skiers, particularly at high inclination angles. Minimisation of this motion allows a noticeable reduction of this force and hence of the risk of injury. We make a detailed comparison between the model and the results of a field study of slalom turns and find a very good agreement. This suggests that the pendulum model is a useful mathematical tool for analysing the dynamics of skiing. [ABSTRACT FROM AUTHOR]

Efficient work of grids with the maximum potential utilization, together with supply and modern consumer satisfaction, as well as unpredictability of distributed energy sources, represents the challenge of successful load management. This paper proposes the load management framework and analyses state-of-the-art research activities from the area of load management in smart grids. It addresses three steps in load management framework: modelling and prediction, measurement and monitoring, and optimization and control. The original contribution of this meta-analysis and state-of-the-art review is a multi-factor approach to the process of load management with the identification of key influence factors from groups: system, context and user. [ABSTRACT FROM AUTHOR]

In bonding processes, the final distribution of the adhesive in the gap depends on the compressing normal load, velocity and kinematics, the adhesive properties, but above all on the initial adhesive distribution. The latter is also largely responsible for trapped air and the adhesive squeezes out at the edges. A model has recently been developed for the simulation of the flows during compression processes in adhesively bonded joints. This paper extends the aforementioned model towards shear rate-dependent viscosity, a phenomenon crucial for most industrial adhesives. Besides the assumption of a Newtonian fluid, approximations of a power-law and a Yasuda law are used. For this purpose, a further subordinate Newton method for determining the flow profiles is added to the existing model. Rheological measurements over a wide range of shear rates serve as a reference. For the verification, studies are performed on two academic examples: a rectangular, and a circular propagation. The results are compared with analytical solutions and CFD simulations. A very good agreement of pressure (deviations below 1.5%), and velocity profiles (deviations below 5%), for all scenarios and flow laws, was found. The long-term goal of this model development is the prediction of adhesive compression flows for complex application patterns. [ABSTRACT FROM AUTHOR]

Climatic impacts on the environment, land cover and land use change such as urbanisation and deforestation affect rainfall and change riverflow responsiveness and seasonal flows as a result of their influence on nonlinear behaviour of the catchments of rivers. Water supply is seriously affected which invariably impacts on domestic activities and agriculture. In some countries river transportation, hydropower, irrigation and fish farming are at risk due to these impacts. Within this paper, a review of existing hydrological and climatic studies in Africa and Ghana in particular is presented. The paper highlights the knowledge gaps identified in the review, such as rainfall-riverflow processes and their controls in the country, estimation of cycles in evapo-transpiration and solar radiation time series, together with the complete characterisation of the temporal and spatial fluctuations within the climate cycles. The establishment of a monograph of catchment response characteristic across the Ghanaian latitudinal gradient and if possible across the tropics is recommended. This could be used for the prediction of hydrologic response of ungauged catchments in the country. [ABSTRACT FROM AUTHOR]

Dispersive failures have been reported throughout the world in the recent past. Soils, in which they occur, are vulnerable to erosion even in quiet water. The initiation of dispersive failure below the pavement layers would progress without any sign and the consequences would be more severe than other types of pavement failure. This paper describes a theoretical development of an analytical model to quantify the mass of particle loss due to dispersion failure below the pavement layers and the associated transport and deposition of the detached particles. The analytical model is validated using the experimental results for four different materials with dispersive characteristics. The model calculations are compared with the experimental results and a close correlation is found between the model-calculated and experimental results. The calculated total mass loss per unit area for the most dispersive soil is 1.90 g/cm2, which is very close to the experimental result of 1.72 g/cm2. The study indicates that the mass loss in the first water contact is significantly greater than those in the subsequent cycles for all the materials in the analytical and experimental results. Also, the calculated total mass loss is very close to the experimental results. [ABSTRACT FROM AUTHOR]

Tidal stream turbines operate in the harsh marine environment, subjected to turbulence, wave action and wakes from upstream devices when deployed in arrays. Turbines may be mounted on the sea bed or on floating platforms. Numerical models are invaluable to study individual and array performance and their interaction with environmental flows. To date, shallow water models and three-dimensional Reynolds averaged Navier–Stokes (RANS) simulations predominate the simulation of turbine arrays, while large-eddy simulation (LES) is becoming more widely used due to availability of high-performance computing resources. The accuracy of turbine performance and load prediction depends on the ability to represent turbulence in the tidal flow and unsteady wake effects. Inclusion of waves increases the modelling complexity and is particularly significant for floating platforms. In this Vision Paper, we provide a perspective on the numerical approaches currently used for modelling tidal flows and marine turbines, suggesting future challenges envisaged in this field. [ABSTRACT FROM AUTHOR]

This paper uses the theories of practice architectures and learning to teach to study in-service teachers' practice of learning to teaching within a further education (FE)-based initial teacher education (ITE) classes at one further education college (FEC) in England. It seeks to answer two research questions: How do in-service teachers learn how to teach within a teacher education classes at a general FE college in England? What site-based factors shape the in-service teachers' practice of learning to teach? Using an action research methodology, the researcher, a university-based teacher educator, worked with a team of six FE-based teacher educators and their 35 in-service teachers to answer these questions. Drawing on data from six 'teacher talk' meetings with the teacher educators and three focus groups with the in-service teachers, the paper builds on and adds to international maps of existing research and knowledge of their practice of learning to teach. [ABSTRACT FROM AUTHOR]