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Terrain feature points, such as peaks, pits, and saddles, represent the macro-structure of the landform. Conventional techniques for extracting these points from digital elevation models (DEMs) often grapple with issues of inaccuracy, omission and redundancy, largely due to the problematic necessity of setting threshold values. This paper proposes an innovative approach for the automatic detection of terrain feature points based on the topological relationships of contours and the inherent constraints of terrain shape characteristics. The study provides a robust mathematical model of terrain feature points and an effective algorithm for their extraction. Comparing with manually reference data, the accuracy metrics including completeness, correctness, and quality of our extracted results demonstrate a high level, significantly surpassing those obtained through existing algorithms. This proposed approach not only avoids the spurious feature points produced by the local window method, but also prevents the omission of valid points and the creation of redundant ones. Moreover, by utilizing the contour interval as its only variable, our approach eliminates the need for various threshold settings, streamlining the extraction process. [ABSTRACT FROM AUTHOR]

This paper deals with the mathematical modelling of the electrostatic spraying process in an industrial electrostatic oiling machine (EOM) for steel strips. Measurements from an industrial EOM show that the thickness and inhomogeneity of the oil film on the strips frequently exceed specified tolerance limits whereby the reasons were previously unknown. A numerical model of the spraying process is developed in ANSYS Fluent, which serves as the basis for a root-cause analysis of the erroneous oil film thickness. In contrast to other works in this area, a droplet break-up model, which describes the break-up of the oil droplets due to the charge they carry, is included to get more accurate results. The model is validated based on measurement data from an industrial oiling machine. It is demonstrated that the model yields a better understanding of the spraying process and it is successfully used to improve the oiling process. [ABSTRACT FROM AUTHOR]

Leishmaniasis, an infectious disease, manifests itself mostly in two forms, cutaneous leishmaniasis (CL) and, a more severe and potentially deadly form, visceral leishmaniasis (VL). The current control strategy for leishmaniasis relies on chemotherapy drugs such as sodium antimony gluconate (SAG) and meglumine antimoniate (MA). However, all these chemotherapy compounds have poor efficacy, and they are associated with toxicity and other adverse effects, as well as drug resistance. While research in vaccine development for leishmaniasis is continuously progressing, no vaccine is currently available. However, some experimental vaccines such as LEISH-F1+MPL-SE (V) have demonstrated some efficacy when used as drugs for CL patients. In this paper we use a mathematical model to address the following question: To what extent vaccine shots can enhance the efficacy of standard chemotherapy treatment of leishmaniasis? Starting with standard MA treatment of leishmaniasis and combining it with three injections of V , we find, by Day 84, that efficacy increased from 29% to 65–91% depending on the amount of the vaccine. With two or just one injection of V , efficacy is still very high, but there is a definite resurgence of the disease by end-time. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a leading cause of death worldwide. Making matters worse, nearly 463 million people have diabetes, which increases atherosclerosis-related inflammation. Diabetic patients are twice as likely to have a heart attack or stroke. In this paper, we consider a simplified mathematical model for diabetic atherosclerosis involving LDL, HDL, glucose, insulin, free radicals (ROS), β cells, macrophages and foam cells, which satisfy a system of partial differential equations with a free boundary, the interface between the blood flow and the plaque. We establish the existence of small radially symmetric stationary solutions to the model and study their stability. Our analysis shows that the plague will persist due to hyperglycemia even when LDL and HDL are in normal range, hence confirms that diabetes increase the risk of atherosclerosis. [ABSTRACT FROM AUTHOR]

Populations are generally censused daily, weekly, monthly or annually. In this paper, we introduce a discrete-time nutrients-phytoplankton-oysters (NPO) model that describes the interactions of nutrients, phytoplankton and oysters in a bay ecosystem. We compute the threshold parameter $ \mathcal {R}_N $ R N for persistence of phytoplankton with or without oysters. When $ \mathcal {R}_{N} \lt 1 $ R N < 1 , then both phytoplankton and oysters populations go extinct. However, when $ \mathcal {R}_N \gt 1 $ R N > 1 , we show that the model may exhibit two scenarios: (1) a locally asymptotically stable equilibrium with positive values of nutrients and phytoplankton with oysters missing, and (2) a locally asymptotically stable interior equilibrium with positive values of nutrients, phytoplankton and oysters. We use sensitivity analysis to study the impact of human and environmental factors on the model. We use examples to illustrate that some human activities and environmental factors can force the interior equilibrium to undergo a Neimark–Sacker bifurcation which generates phytoplankton blooms with oscillations in oysters population and nutrients level. [ABSTRACT FROM AUTHOR]

The world is grappled with an unprecedented challenges due to Corona virus. We are all battling this epidemic together, but we have not been able to defeat this epidemic yet. A new variant of this virus, named 'Omicron' is spreading these days. The fractional differential equations are providing us with better tools to study the mathematical model with memory effects. In this paper, we will consider an extended SER mathematical model with quarantined and vaccinated compartment to speculate the Omicron variant. This extended Susceptible Exposed Infected Recovered SER model involves equations that associate with the group of individuals those are susceptible (S), exposed (E): this class includes the individuals who are infected but not yet infectious, infectious (W): this class includes the individuals who are infected but not yet Quarantined, quarantined (Q): this class includes those group of people who are infectious, confirmed and quarantined, recovered (R) this class includes the group of individuals who have recovered, and vaccinated (V): this class includes the group of individuals who have been vaccinated. The non-negativity and of the extended SER model is analysed, the equilibrium points and the basic reproduction number are also calculated. The proposed model is then extended to the mathematical model using AB derivative operator. Proof for the existence and the uniqueness for the solution of fractional mathematical model in sense of AB fractional derivative is detailed and a numerical method is detailed to obtain the numerical solutions. Further we have discussed the efficiency of the vaccine against the Omicron variant via graphical representation. [ABSTRACT FROM AUTHOR]

Considering carbon emissions when making supply chain decisions has been an essential contributor for keeping this world more sustainable. This paper presents a mixed-integer linear programming (MILP) model to optimize production and transportation decision where the transportation activities involve a multimodal combination. The proposed mathematical model was aimed at mini- mizing the total costs incurred from supply chain activities as well as the emissions generated. Carbon cap is used to ensure that the emissions produced in the whole activities do not exceed the allowable limit. In this research, we address a multi- product, multi-plant, multi-departure, and arrival stations where multiple customers are to be served for multiple periods. The numerical tests show that the demand, carbon tax, and distance significantly affected the total emissions and the total costs. Interestingly, we observed that the decisions are much more affected by the logistical costs rather than the emission costs. The model presented in this paper can assist the decision makers to make production, delivery, and inventory decisions when multi-modal transportation is involved. [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]

Aiming at the problem of autonomous collision avoidance of unmanned vessels in the case of multiple vessels encountering at sea, this paper proposes a method for collision avoidance of vessels in open water based on the Mathematical Model Group (MMG) vessel motion mathematical model. This method uses Model Predictive Control (MPC) model algorithm, and considers vessel maneuverability and the International Regulations for Preventing Collision at Sea, 1972 (COLREGs), and uses fuzzy mathematics to analyze the collision risk of vessels during navigation, and then constructs the evaluation function of the collision avoidance algorithm. The vessel's autonomous collision avoidance is realized. The simulation results show that the algorithm can solve the problem of autonomous vessel collision avoidance in the case of multi-vessel encounters in open water, which verifies the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

The paper aims at examining the properties of innovative processes with regard to Schumpeter premises on factors and drivers of the development of the economy. Due to the analysis of the changes of the characteristics of the economic entities formalised in a mathematical model, two new indexes, namely, an index of the creative destruction, as well as an innovators' competitiveness index, are defined. As a result, we get a formal relationship between a size of innovators' competitiveness and a level of innovativeness. These findings give us the tools for distinguishing the qualitative properties of economic transformations. In the consequence, we obtain a coherent and unified study of innovative processes in Polish regions. [ABSTRACT FROM AUTHOR]

The purpose of this study is, firstly, to examine capital structure optimization and secondly, to provide a framework for determining the optimal capital structure from the aspect of capital cost and corporate value. The results of our work provide an innovative model for arriving at a company's optimal capital structure based on the estimation of the effective cost of capital and the determination of the shares of new equity and long-term debt that will both minimize the overall cost of capital and maximize its value. The model can be applied for quantitative estimates of optimal capital structure. This paper contributes to the literature by applying mathematical modeling and mathematical theory of optimization to solve the problem of capital structure optimization, and by providing a framework for determining optimal capital structure. The scientific contribution of this research is development of a model of optimal capital structure from the aspect of capital cost and corporate value, and new equations for calculating the effective costs of long-term financing sources. This model provides explicit advice on optimal long-term debt and equity level and can be applied to produce a firm-specific recommendation about optimal capital structure that a given company should use. [ABSTRACT FROM AUTHOR]

Mathematical modelling of the simplest Takagi-Sugeno fuzzy Two-Input Two-Output (TITO) Proportional-Integral/Proportional-Derivative (PI/PD) controller is presented in this paper. Mathematical model of fuzzy PI/PD controller is proposed using Algebraic Product (AP) t-norm, Bounded Sum (BS) t-co-norm and Center of Gravity (CoG) defuzzifier. The inputs are fuzzified by fuzzy sets having L and type membership functions. The rule base consists of five rules with different linear models in the consequent parts. Both static and dynamic couplings are taken into account while deriving the models. The model of the fuzzy PI/PD controller reveals that it is a variable gain/structure controller. Also, each output of the TITO fuzzy controller is the sum of two nonlinear PI or PD controllers with variable gains. The properties and the gain variations of the controllers are investigated. [ABSTRACT FROM AUTHOR]

Among the various techniques of power scavenging, piezoelectric energy harvesting usually has more power density. Although piezoceramics are usually more efficient than other piezoelectric materials, since they are very brittle and fragile, researchers are looking for alternative materials. Recently Cellulose Electro-active paper (EAPap) has been recognized as a smart material with piezoelectric behavior that can be used in energy scavenging systems. The majority of researches in energy harvesting area, use unimorph piezoelectric cantilever beams. This paper presents an analytical solution based on distributed parameter model for partially covered pieoelectric cantilever energy harvester. The purpose of the paper is to describe the changes in generated power with damping and the load resistance using analytical calculations. The analytical data are verified using experiment on a vibrating cantilever substrate that is partially covered by EAPap films. The results are very close to each other. Also asymptotic trends of the voltage, current and power outputs are investigated and expressions are obtained for the extreme conditions of the load resistance. These new findings provide guidelines for identification and manipulation of effective parameters in order to achieve the efficient performance in different ambient source conditions. [ABSTRACT FROM PUBLISHER]

Building fair, equitable, and beneficial partnerships between institutions collaborating in research in low- and middle-income countries (LMIC) and high-income countries (HIC) has become an integral part of research capacity building in global health in recent years. In this paper, we offer an example of an academic collaboration between the University of California Los Angeles, Center for Health Policy and Research (UCLA CHPR) and the University of Philippines, Manila, College of Public Health (UPM CPH) that sought to build an equitable partnership between research institutions. The partnership was built on a project to build capacity for research and produce data for policy action for the prevention and care of non-communicable diseases (NCDs) through primary healthcare in the Philippines. The specific objectives of the project were to: (1) locally adapt the Primary Care Assessment Tool for the Philippines and use the adapted tool to measure facility-level primary care delivery, (2) conduct focus group discussions (FGDs) to gather qualitative observations regarding primary care readiness and capacity, and (3) conduct a comprehensive population-based health survey among adults on NCDs and prior healthcare experience. We describe here the progression of the partnership between these institutions to carry out the project and the elements that helped build a stronger connection between the institutions, such as mutual goal setting, cultural bridging, collaborative teams, and capacity building. This example, which can be used as a model depicting new directionality and opportunities for LMIC-HIC academic partnerships, was written based on the review of shared project documents, including study protocols, and written and oral communications with the project team members, including the primary investigators. The innovation of this partnership includes: LMIC-initiated project need identification, LMIC-based funding allocation, a capacity-building role of the HIC institution, and the expansion of scope through jointly offered courses on global health. [ABSTRACT FROM AUTHOR]

The goal of this paper is to investigate the influence of the waning immunity on the dynamics of Tilapia Lake Virus (TiLV) transmission in wild and farmed tilapia within freshwater. We formulate a model for which susceptible individuals can contract the disease in two ways: (i) direct mode caused by contact with infected individuals; (ii) indirect mode due to the presence of pathogenic agents in the water. We obtain an age-structured model which combines both age since infection and age since recovery. We derive an explicit formula for the reproductive number R 0 and show that the disease-free equilibrium is locally asymptotically stable when, R 0 < 1. We discuss on the form of the waning immunity parameter and show numerically that a Hopf bifurcation may occur for suitable immunity parameter values, which means that there is a periodic solution around the endemic equilibrium when, R 0 > 1. [ABSTRACT FROM AUTHOR]

The paper's main aim is to investigate the 2019 coronavirus disease in Ethiopia using a fractional-order mathematical model. It would also focus on the importance of fractional-order derivatives that may help us in modelling the system and understanding the effect of model parameters and fractional derivative orders on the approximate solutions of our model. A SELAIQHCR model is constructed using nonlinear differential equations in the Atangana–Baleanu non-integer operator in the Caputo sense. After that, the Chebyshev fourth kind spectral collocation method is used to change a fractional system to an algebraic system. Newton iterative technique is used to solve the converted system. The next-generation matrix technique is used to obtain the effective reproduction number. The COVID-19-free equilibrium point and endemic equilibrium point, solution positivity and boundedness, and their stability are all carefully done. The sensitivity of the effective reproduction value with respect to the key model parameters is discussed. The beginning values provided for our system were obtained using reports from the Ethiopian Public Health Institute from 29 February 2021 to 7 June 2021. The fundamental reproduction number is obtained with R 0 = 1.4331. The model's numerical solutions are represented graphically. [ABSTRACT FROM AUTHOR]

The tubeless vortex reducer was used to reduce the pressure drop in a cavity with radial inflow. In previous studies, the mechanism of vortex breakdown in tubeless vortex reducers was not clear, and there was a lack of direct guidance for engineering design. In this paper, we studied the vortex and pressure in the cavity in detail by large-eddy simulation (LES) and experiments. A mathematical model, which has high applicability and compatibility, was established to guide the pre-design of tubeless vortex reducers. The LES results showed that the high-speed and large-scale vortices broke rapidly at the nozzle inlet and reached the minimum size at the nozzle outlet. Furthermore, the enhancement of vortex in the downstream cavity was restrained. When the rotating speed was relatively low, strong negative vortices formed and the pressure drop increased in the downstream cavity. The experiments showed that the nozzle performance directly affected the flow characteristics and pressure drop in the cavity. Compared with the simple cavity, the tubeless vortex reducer generated lower pressure drop. The average relative error between the mathematical model and the experimental results was only 9.3%. [ABSTRACT FROM AUTHOR]

Variable-thickness rolled blank (VRB) technique is one of the most effective methods to improve the level of lightweight and stiffness characteristics of car body. The shape of thickness transition zone (TTZ) is a key factor for the stiffness characteristics of VRB. For better stiffness characteristics of VRB, a new thickness distribution function (i.e. double-power function) of the transitional zone of VRB is proposed in this paper. Firstly, the mathematical model of the VRB with double-power thickness distribution function is established under manufacturing constraint. Secondly, the static stiffness characteristics of VRB with double-power thickness distribution function are compared with that of the VRB with linear thickness distribution and polynomial thickness distribution under the same weight, respectively. The results show that the static stiffness of the VRB with double-power thickness distribution function owns best characteristics. Finally, the mathematical model of the rolling velocity is established, and the influence of the shape of double-power TTZ on rolling velocity is analysed. The outcome of this work can provide some useful guidance for investigating the rollability of the VRB with double-power thickness distribution function, as well as for designing the stiffness of car body outer panels. [ABSTRACT FROM AUTHOR]

The outbreak of COVID-19 was first experienced in Wuhan City, China, during December 2019 before it rapidly spread over globally. This paper has proposed a mathematical model for studying its transmission dynamics in the presence of face mask wearing and hospitalization services of human population in Tanzania. Disease-free and endemic equilibria were determined and subsequently their local and global stabilities were carried out. The trace-determinant approach was used in the local stability of disease-free equilibrium point while Lyapunov function technique was used to determine the global stability of both disease-free and endemic equilibrium points. Basic reproduction number, R 0 , was determined in which its numerical results revealed that, in the presence of face masks wearing and medication services or hospitalization as preventive measure for its transmission, R 0 = 0.698 while in their absence R 0 = 3.8. This supports its analytical solution that the disease-free equilibrium point E 0 is asymptotically stable whenever R 0 < 1 , while endemic equilibrium point E ∗ is globally asymptotically stable for R 0 > 1. Therefore, this paper proves the necessity of face masks wearing and hospitalization services to COVID-19 patients to contain the disease spread to the population. [ABSTRACT FROM AUTHOR]

The aim of this paper is to discover how regions can change innovation process models and whether less developed regions can, in this sense, break out of the negative path dependency. This paper is one of the few to investigate path dependency from a regional rather than from an industry or product perspective. The application of Ward metrics revealed seven innovation process models that can be combined into three groups according to different regional circumstances, in which: (1) knowledgeintensive services are the main carriers of the innovation processes, (2) innovation processes are mostly expressed through manufacturing, and (3) transitions from one type of innovation process into another are the dominant characteristics. Results indicate that there are indeed many examples of path dependency breakthroughs. They occur mostly in the transition group, and could evolve into either one of the other two groups. The research revealed two types of manufacturing regions, namely low-tech and high-tech. It also confirmed that less developed regions fall within the low-tech model called 'primary-sector-based manufacturing regions' and face difficulties when phasing into higher-tech models, e.g. only 4% of all transitions are from this model. It is therefore challenging to break out of a negative path dependency. Moreover, the research signified that the reasons for growth are model specific. Therefore, when aiming to achieve an innovation process model transition, regional policies should be tailored accordingly; thus, an evolutionary, staged process of regional policy would be worth researching further. [ABSTRACT FROM AUTHOR]

In this paper, the nonlinear problem of the 1 D Swift-Hohenberg equation (S-HE) has been solved by using five reliable iterative methods. The first one is the Daftardar-Jafari method namely (DJM), the second method is the Temimi-Ansari method namely (TAM), the third method is the Banach contraction method namely (BCM), the fourth method is the Adomian decomposition method namely (ADM) and finally the fifth method is the Variational iteration method (VIM) to obtain the approximate solutions. In this work, we discussed and applied these iterative methods to solve the S-HE and compared them. In addition, the fixed-point theorem was given to illustrate the convergence of the five methods. To illustrate the accuracy and efficiency of the five methods, the maximum error remainder was calculated since the exact solution is unknown. The results showed that the five iterative methods are accurate, reliable, time saver and effective. All the iterative processes in this paper implemented in MATHEMATICA®11. [ABSTRACT FROM AUTHOR]

The paper presents the results of a study done to find the optimal shapes of matrix element partitioning on three abstract heterogeneous processors when performing multiplication operations. An abstract processor model allows applying the research results in systems with different heterogeneous architectures. To determine the optimal partitioning shape, the work uses non-rectangular candidate shapes identified by Ashley DeFlumere in her work as a result of applying the technology of redistribution of matrix elements between the processors «push»: Square Corner, Rectangle Corner, Square Rectangle, Block Rectangle, L-Rectangle, Traditional 1D Rectangular. The optimality of shapes is determined for four classes of matrix multiplication algorithms: Serial Communication with Barrier (SCB), Parallel Communication with Barrier (PCB), Serial Communication with Bulk Overlap (SCO) and Parallel Communication with Overlap (PCO). The Hockney model was used to evaluate the communication complexity of algorithms. Mathematical models of the algorithm execution time were introduced in the paper for each considered candidate shape in all algorithms. Based on the developed mathematical models, software was developed that allows to select the form of elements partitioning between processors, depending on the ratio of their speeds and latency of the transmission medium. [ABSTRACT FROM AUTHOR]

Load forecasting is an essential operation in the power utility industry. However, a common challenge is faced for adjusting forecasting models to fit the need for substations' load prediction as well as minimizing expenditure in IT resources for repurposing these forecasting models to bigger datasets. The goal of this paper is to propose a novel solution that is responsive to these demands through the integration of reinforcement learning with load forecasting on existing database technology. To deal with the varying accuracy of the forecasting models on different substations' loads, the proposed solution compares and uses the best models and recalibrate them iteratively by comparing the model's prediction against the actual load data. As shown in empirical analysis, the solution interacts with the environment and performs the optimum forecasting routine intuitively. [ABSTRACT FROM AUTHOR]

This paper explores the prospects of commercial producers who would be willing to exit voluntarily in the near future to make land available in the market. In addition, it also considers what factors are restricting the acceleration of this rate of exit from a land-supply perspective with respect to barriers to exit. The prospect of structural change from such acceleration is also explored using three scenarios. An agent-based mathematical model is used to implement the three scenarios. This model is constructed from a dataset of 450 commercial producers across South Africa. The results suggest that a reasonable amount of arable land could be available for redistribution, with only modest structural change regarding animal production, despite drastic alterations in veld. These results provide some guidelines on how assistance for struggling producers can make land available for efficient producers, which could make the sector stronger. All potential exiting commercial producers have common reasons for doing so, which could be used to initiate a positively inclined, structured discussion on land supply. [ABSTRACT FROM AUTHOR]

Water body extraction is an important part of water resource management and has been the topic of a number of research works related to remote sensing for over two decades. Extracting water bodies from satellite images with a pixel-based method or indexes cannot eliminate other objects that have a low albedo, such as shadows and built-up areas. Since their spectral differences cannot be separated, in this paper a method that combines a pixel-based index and object-based method has been used on a Sentinel-2 satellite image with a resolution of 10 m. The method uses image segmentation on a multispectral image containing 13 bands. It also uses indexes used for extracting water bodies, such as the Normalized Difference Water Index (NDWI). Two study areas with different characteristics have been chosen, one mountainous and one urban region, both of them located in Macedonia. Using object-based techniques and pixel-based indexes, such as NDWI, the results from the NDWI have been improved by a kappa value of more than 0.5. [ABSTRACT FROM PUBLISHER]

The primary objective of this work is to investigate the existence of mild solutions for some neutral stochastic integrodifferential systems in Hilbert spaces. These systems have a state-dependent delay and noninstantaneous impulses. In order to achieve this objective, the neutral stochastic integrodifferential system that has been proposed with state-dependent delay and noninstantaneous impulses is converted into an equivalent fixed point problem by means of an appropriate integral operator.Together with the theory of stochastic analysis, we develop several existence results that are founded on the theory of resolvent operators in the sense of Grimmer, Hausdorff's measures of noncompactness, and fixed point theorems.In the last part of this paper, specific examples are used to show how the general conclusions reached in this paper are made. [ABSTRACT FROM AUTHOR]

The oil industry in Thailand primarily relies on truck transportation due to the versatility of trucks. Different truck sizes can easily access many customer locations better than any other transportation mode. However, although trucks have many advantages, the transportation cost per unit is very expensive compared to railway, air, waterway, and pipe transportation modes. Previous data indicated that shipping costs were approximately 703.995 USD/month/fleet and the transportation utilization was 83.145%. Therefore, efficiencies should be identified to improve business operations. This paper proposes an oil transportation plan with transshipment points by adopting Network Flow Models (NFM) to develop a Generalized Network Flow Model (GNFM). The developed GNFM was applied to solve three different problems and compared to the existing method. The objectives of the proposed model were to minimize total cost and maximize truck efficiency. Multi-Criteria Decision Analysis (MCDA) was considered to set the optimal decision criteria for managing the oil transportation network with the transshipment sites. The proposed model with the Cluster Model (CT) provided optimal results, with a total cost of 663.539 USD/month/fleet and a truck efficiency of 88.029%. [ABSTRACT FROM AUTHOR]

Modelling the human cardiorespiratory system using computer simulation tools can serve to help physicians to comprehend the causes and development of cardiorespiratory diseases. The objective of this paper is to develop an integrated model of the cardiovascular and respiratory systems, along with their intrinsic control mechanisms, by combining analogous hydraulic-electric and diffusion-electric circuits, respectively. This modelling task is performed in object-oriented language in SIMSCAPE using the physical interconnected components to define the underlying dynamic equations. Simulation steady state results under rest and under variable physical exercise conditions, as well as under limiting conditions show a high qualitative agreement with clinical observations reported in literature. This object-oriented modelling approach, based on the combined use of electrical analogies, proves to be avaluable tool as a test bench for different strategies aimed to qualitative prediction of the effects of cardiorespiratory interactions during exercise, thus avoiding the formulation of complex mathematical models. [ABSTRACT FROM AUTHOR]

Since mathematical models play a key role in investigating the dynamics of infectious diseases, many mathematical models for these diseases are developed. In this paper, it is aimed to determine the dynamics of Tuberculosis (TB) in Turkey, how much it will affect the future and the impact of vaccine therapy on the disease. For this purpose, three mathematical models (SIR, SEIR and BSEIR) in the literature are considered for the case of Turkey. The model parameters are obtained with TB reported data from 2005 to 2015 by using the least square method. The obtained results revealed that the basic reproduction ratio for all three models is less than 1. Moreover, the stability analysis of the models and sensitivity analysis of the model parameters are presented and discussed. Finally, the accuracy of results for all three models is compared and the effect of the vaccination rate is discussed. [ABSTRACT FROM AUTHOR]

Self-medication is an important initial response to illness in Africa. This mode of medication is often done with the help of African traditional medicines. Because of the misconception that African traditional medicines can cure/prevent all diseases, some Africans may opt for COVID-19 prevention and management by self-medicating. Thus to efficiently predict the dynamics of COVID-19 in Africa, the role of the self-medicated population needs to be taken into account. In this paper, we formulate and analyse a mathematical model for the dynamics of COVID-19 in Cameroon. The model is represented by a system of compartmental age-structured ODEs that takes into account the self-medicated population and subdivides the human population into two age classes relative to their current immune system strength. We use our model to propose policy measures that could be implemented in the course of an epidemic in order to better handle cases of self-medication. [ABSTRACT FROM AUTHOR]

Purpose: Understanding the nature of wellbeing as multidimensional and complex provides a policy window to generate a strengths-based policy orientation to promote wellbeing in education settings. The purpose of this exploratory paper is to map how wellbeing is interpreted across public education policy documents in Aotearoa New Zealand. Method: To explore the narrative that this group of documents weave, we draw on models of holistic wellbeing, ecological systems and appreciative inquiry. Policy documents were analysed using text mining software to track notions of wellbeing; their occurrence and co-occurrence with related concepts. Results: Key findings include the predominance of wellbeing, the interrelatedness of wellbeing with relationships, and the predominance of student wellbeing over the wellbeing of other stakeholders, highlighting that current education policy does not interpret wellbeing as relational, complex or contextual. Conclusion: We argue that interpreting such documents through a wellbeing lens demonstrates the complexity and disparity of the conceptualization and contextualization. We assert that it is critical to explore possibilities for deliberate and ecological wellbeing connections within educational policy and practice for the good of all stakeholders. [ABSTRACT FROM AUTHOR]

When the spinal surgery robot assists the surgeon perform the surgery, the patient is prone on the operating table. However, due to the force of the surgical instruments on the spine, there is a corresponding deformation in the surgical field, which affects the accuracy of the operation. In order to improve the accuracy and safety of the operation, this paper reconstructs the three-dimensional model of the lumbar spine which includes the vertebral body and the intervertebral disc based on the CT scan data, and then the lumbar spine is analyzed by the finite element method. The mathematical model of the relationship between force and displacement is established by using response surface methodology based on the simulation results. After that, the position control system is constructed based on the mathematical model. Through the simulation of the control system, the trajectory curve of the end of the manipulator is compared and the validity of the mathematical model is verified. [ABSTRACT FROM AUTHOR]

Child health is taking the back seat in development strategies. In summarising a newly released collaborative report, this paper calls for a novel conceptual model where child health takes centre stage in relation to the 2030 Agenda and the Sustainable Development Goals. It lays out five principles by which renewed effort and focus would yield the most benefit for children and adolescents. These include: re-defining global child health in the post-2015 era by placing children and adolescents at the centre of the Sustainable Development Goals; striving for equity; realising the rights of the child to thrive throughout the life-course; facilitating evidence informed policy-making and implementation; and capitalising on interlinkages within the SDGs to galvanise multisectoral action. These five principles offer models that together have the potential of improving design, return and quality of global child health programs while re-energising the 2030 Agenda and the Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

The paper presents a model for the evolution of an infectious disease in a population with individual-specific immunity. The immune state of an individual varies with time according to its own dynamics, depending on whether the individual is infected or not. The model involves a system of size-structured (first-order) PDEs that capture both the dynamics of the immune states and the transition between compartments consisting of infected, susceptible, etc. individuals. Due to the unavailability of precise data about the immune states of the individuals, the main focus in the paper is on developing a technique for set-membership estimations of aggregated quantities of interest. The technique involves solving specific optimization problems for the underlying PDE system and is developed up to a numerical method. Results of numerical simulations are presented for a benchmark model of SIS-type, potentially applicable to diseases like influenza and to various sexually transmitted diseases. [ABSTRACT FROM AUTHOR]

Background: This paper reports on a research study that aims to identify and explain barriers to knowledge sharing (KS) in the provision of healthcare referral services in Chinese healthcare organisations. Design: An inductive case study approach was employed, in which 24 healthcare professionals and workers from four healthcare organisations in the province of Hubei, Central China, were interviewed using semi-structured scripts. Results: Through data analysis, 14 KS barriers emerged in four main themes: interpersonal trust barriers, communication barriers, management and leadership barriers, and inter-institutional barriers. A cause-consequence analysis of the identified barriers revealed that three of them are at the core of the majority of problems, namely, the absence of national and local policies for inter-hospital KS, lack of a specific hospital KS requirement, and lack of mutual acquaintance. Conclusions: To resolve KS problems, it is of great importance that healthcare governance agencies, both at the national and regional levels, take leadership in the process of KS implementation by establishing specific and strong policies for inter-institutional KS in the referral process. This paper raises important issues that exceed academic interests and are important to healthcare professionals, hospital managers, and Information communication technology (ICT) managers in hospitals, as well as healthcare politicians and policy makers. [ABSTRACT FROM AUTHOR]

This paper aims to provide an analytical insight on the current state of knowledge on gender-based violence among people with disabilities, a topic where the level of data is relatively low. We briefly discuss the current research on: (a) the prevalence, risk factors and the theoretical approaches for gender-based violence among people with disabilities. (b) Service provision among people with disabilities who experience gender-based violence. (c) We also highlight areas where further research is required, the applicable theoretical approaches and provide an example on how Sweden is attempting to bridge this knowledge gap through implementing the Disability and Intimate-partner violence project (DIS-IPV) project. [ABSTRACT FROM AUTHOR]

The design and tuning of controllers for the industrial process is an art, which plays a vital role in many of the process control industries. The industries such as sugar, chemical, paper and other process control-based industries hold the nature of non-linearity due to their uneven distribution of load influence with disturbances. This paper highlights the study and investigation of different controlling parameters associated with the sugar industry which is located in the southern region of Tamil Nadu, India. After the analysis of various processes, the impact of controlling strategy needs to be implemented in an advanced way to minimize the resource utilization with high productivity. The behaviour of various process parameters, such as flow, temperature, level, pressure, is studied and one of these has been discussed in detail along with the controller design. The controller, such as proportional, integral, derivative, has been modified with advanced control phenomena and applied to process model with the presence of delay time provides the excellent tracking of operating point to bring the stability of a certain process in a tremendous manner. [ABSTRACT FROM AUTHOR]

Cell-fate networks are traditionally studied within the framework of gene regulatory networks. This paradigm considers only interactions of genes through expressed transcription factors and does not incorporate chromatin modification processes. This paper introduces a mathematical model that seamlessly combines gene regulatory networks and DNA methylation (DNAm), with the goal of quantitatively characterizing the contribution of epigenetic regulation to gene silencing. The 'Basin of Attraction percentage' is introduced as a metric to quantify gene silencing abilities. As a case study, a computational and theoretical analysis is carried out for a model of the pluripotent stem cell circuit as well as a simplified self-activating gene model. The results confirm that the methodology quantitatively captures the key role that DNAm plays in enhancing the stability of the silenced gene state. [ABSTRACT FROM AUTHOR]

Between February and May 2020, New Zealand recorded 1504 cases of COVID-19 before eliminating community transmission of the virus in June 2020. During this period, a series of control measures were used including population-wide interventions implemented via a four-level alert system, border restrictions, and a test, trace, and isolate system. Mathematical modelling played a key role in informing the government response and guiding policy development. In this paper, we describe the development of a stochastic mathematical model for the transmission and control of COVID-19 in New Zealand. This includes features such as superspreading, case under-ascertainment, testing and reporting delays, and population-wide and case-targeted control measures. We show how the model was calibrated to New Zealand and international data. We describe how the model was used to compare the effects of various interventions in reducing spread of the virus and to estimate the probability of elimination. We conclude with a discussion of the policy-modelling interface and preparedness for future epidemic outbreaks. [ABSTRACT FROM AUTHOR]

The paper reports a new mathematical model for understanding the mechanism delivery from drug release systems. To do this, two drug release systems based on chitosan and diclofenac sodium salt as a drug model, were prepared by in situ hydrogelation in the presence of salicylaldehyde. The morphology of the systems was analyzed by scanning electron microscopy and polarized light microscopy and the drug release was in vitro investigated into a medium mimicking the in vivo environment. The drug release mechanism was firstly assessed by fitting the in vitro release data on five traditional mathematical model. In the context of pharmacokinetics behavioral analysis, a new mathematical procedure for describing drug release dynamics in polymer-drug complex systems was proposed. Assuming that the dynamics of polymer-drug system's structural units take place on continuous and nondifferentiable curves (multifractal curves), it was showed that in a one-dimensional hydrodynamic formalism of multifractal variables the drug release mechanism is given through synchronous dynamics at a differentiable and non-differentiable scale resolutions. [ABSTRACT FROM AUTHOR]

Scarlet fever is an acute respiratory infectious disease and the incidence rate is increasing from 2011 throughout the world. In this paper, the mathematical models are proposed, which incorporate both direct transmissions and indirect transmissions of scarlet fever. The threshold conditions for disease invasion are obtained in terms of the basic reproduction number. The peak value, final size and epidemic time in a seasonal prevalence are investigated numerically. Furthermore, the effects of seasonal fluctuations on disease outbreak are also studied on the basis of real data in China. [ABSTRACT FROM AUTHOR]

Demands for out-of-hours primary care (OOH-PC) services are increasing. Many citizens call because of non-urgent health problems. Nevertheless, the patients' motives for requesting medical help outside office hours remains an understudied area. This study aimed to examine motives for calling OOH-PC services in various age groups. Cross-sectional paper based questionnaire study conducted during two weeks in 2015. The OOH-PC services in two Danish regions. Randomly selected patients calling the two healthcare services and accepting to participate in the study received a questionnaire on patient characteristics, health problems, and 26 pre-defined motives based on the Andersen Behavioural Model. Multivariate regression analyses were conducted for various age groups to calculate the probability of each motive to be a significant factor for the decision to call. A total of 1,871 patients were included in the study; half were parents of children aged 0-12 years. Young adults (18 to 39 years) differed significantly from other age groups as they more often stated perceived barriers and benefits such as "Own GP no time available soon enough" and "Need for quick help because of work". Young adults more often perceive barriers and benefits, which may suggest af difference in expectations regarding the purpose of out-of-hours services and accessibility. Further research is needed to address this issue and further explore the potential gap between the citizens' expectations to the OOH-PC services and the prevailing health policies. The out-of-hours primary healthcare services are increasingly contacted for non-urgent problems, but little is known about the citizens' motives for calling. Age is associated with differences in the perceived importance of various motives for calling out-of-hours care. Young adults are more often than other age groups motivated to call due to logistical issues, such as their job. [ABSTRACT FROM AUTHOR]

In recent years sampling approaches have been used more widely than optimization algorithms to find parameters of conceptual rainfall–runoff models, but the difficulty of calibration of such models remains in dispute. The problem of finding a set of optimal parameters for conceptual rainfall–runoff models is interpreted differently in various studies, ranging from simple to relatively complex and difficult. In many papers, it is claimed that novel calibration approaches, so-called metaheuristics, outperform the older ones when applied to this task, but contradictory opinions are also plentiful. The present study aims at calibration of two simple lumped conceptual hydrological models, HBV and GR4J, by means of a large number of metaheuristic algorithms. The tests are performed on four catchments located in regions with relatively similar climatic conditions, but on different continents. The comparison shows that, although parameters found may somehow differ, the performance criteria achieved with simple lumped models calibrated by various metaheuristics are very similar and differences are insignificant from the hydrological point of view. However, occasionally some algorithms find slightly better solutions than those found by the vast majority of methods. This means that the problem of calibration of simple lumped HBV or GR4J models may be deceptive from the optimization perspective, as the vast majority of algorithms that follow a common evolutionary principle of survival of the fittest lead to sub-optimal solutions. [ABSTRACT FROM PUBLISHER]

This paper presents a methodology aimed to acquire traffic flow data through the employment of unmanned aerial vehicles (UAVs). The study is focused on the determination of driving behavior parameters of road users and on the reconstruction of traffic flow Origin/Destination matrix. The methodology integrates UAV flights with video image processing technique, and the capability of geographic information systems, to represent spatiotemporal phenomena. In particular, analyzing different intersections, the attention of the authors is focused on users’ gap acceptance in a naturalistic drivers’ behavior condition (drivers are not influenced by the presence of instruments and operators on the roadway) and on the reconstruction of vehicle paths. Drivers’ level of aggressiveness is determined by understanding how drivers decide that a gap is crossable and, consequently, how their behavior is critical in relation to a moving stream of traffic with serious road safety implications. The results of these experiments highlight the usefulness of the UAVs technology, that combined with video processing technique allows the capture of real traffic conditions with a good level of accuracy. [ABSTRACT FROM PUBLISHER]

Studies in transportation planning routinely use data in which location attributes are an important source of information. Thus, using spatial attributes in urban travel forecasting models seems reasonable. The main objective of this paper is to estimate transit trip production using Factorial Kriging with External Drift (FKED) through an aggregated data case study of Traffic Analysis Zones in São Paulo city, Brazil. The method consists of a sequential application of Principal Components Analysis (PCA) and Kriging with External Drift (KED). The traditional Linear Regression (LR) model was adopted with the aim of validating the proposed method. The results show that PCA summarizes and combines 23 socioeconomic variables using 4 components. The first component is introduced in KED, as secondary information, to estimate transit trip production by public transport in geographic coordinates where there is no prior knowledge of the values. Cross-validation for the FKED model presented high values of the correlation coefficient between estimated and observed values. Moreover, low error values were observed. The accuracy of the LR model was similar to FKED. However, the proposed method is able to map the transit trip production in several geographical coordinates of non-sampled values. [ABSTRACT FROM AUTHOR]

In this paper, we offer a perspective on complementarity, acknowledging that it is not possible for human perception and cognition to grasp reality with unambiguous concepts or theories. Therefore, multiple concepts and perspectives are valid when they are not exaggerated beyond reasonable limits and do not claim exclusive validity. We recommend a humble stance enabling respectful dialogue between different perspectives in medical science and practice.KEY POINTSNo single perspective in clinical or scientific medicine can exhaustively explain medical phenomena.Scientific attitude is characterised by a willingness to look for objections against what we prefer as truths.Complementarity or unifying contradictions are concepts that allow for humility and pluralism in clinical and scientific medicine. [ABSTRACT FROM PUBLISHER]

While disability is recognised by the United Nations Convention on the Rights of Persons with Disabilities (CRPD) as an evolving concept, the language of positive behaviour support has not kept pace with the current human rights-based approach. The widely-used terms 'challenging behaviour' and 'behaviours that challenge' imply that the behaviour is inherent in a person with disability. Words have power in shaping practice: when the behaviour of the person with disability is framed as the problem, this leads to a pathologisation or labelling that can provide a rationale to medicate and restrain as a way of 'managing the challenging behaviour'. Many behaviours seen as being challenging could be better understood as 'adaptive behaviours to maladaptive environments', or legitimate responses to difficult environments and situations. In this paper, we argue that the language and implementation of positive behaviour support should better take into account the CRPD and contemporary evidence on behaviour change interventions, which support a shift away from focusing on individuals' behaviours towards putting environments front and centre. We outline how the social-ecological model could be used as a framework to more explicitly address 'environments of concern' in developing tailored and system-wide responses to behaviour support needs. We argue there is an urgency for this paradigm shift to better reflect the views of people with disability and improve outcomes. [ABSTRACT FROM AUTHOR]

In this paper, a numerical solution of general form of fractional delay integro-differential equation (GFDIDE) is presented using spectral collocation method. The Chebyshev polynomials of the second kind are used as a basis function with the collocation scheme. The proposed equation represents a general form of intgro-differential equation with delayed argument, which has multi-terms of integer and fractional order derivatives for delayed or non-delayed terms. The operation matrices for all terms of GFDIDE are introduced according to fractional calculus. The reliability and efficiency of the proposed method are demonstrated by some numerical examples. [ABSTRACT FROM AUTHOR]

In this paper, the distortion in homogeneous transversely isotropic thermoelastic (TIT) axisymmetric 2-D thin circular plate with two temperature due to time-harmonic sources have been analysed. The mathematical model has been formed for the rotating thin circular plate with multi-dual-phase-lag generalized heat transfer and has been converted to dimensionless form. The Hankel transform method has been employed to solve the mathematical model. A bicubic equation obtained for nontrivial solution of mathematical model so obtained is solved using MATLAB software. A normal force of unit magnitude and a cubical thermal source and vanishing tangential stress at the boundaries has been taken as boundary conditions. As an application a constant load and a decaying heat source in the radial and axial direction of the thin circular plate has been taken. The displacement components, conductive temperature, and stress components are computed in the transformed domain and numerical inversion techniques are used to find the expressions in the physical domain. The effects of time harmonic frequency and rotation with two temperatures have been represented graphically using MATLAB and analysed for multi-dual phase lag model of heat transfer. Some particular cases have also been discussed. [ABSTRACT FROM AUTHOR]

In this paper we present the development of numerical methods for two problems in chemical engineering: adsorption of carbon dioxide into phenyl glycidyl ether and diffusion and reaction processes in a porous catalyst. Both problems are modelled by systems of two coupled nonlinear ordinary differential equations. Dirichlet and Neumann type boundary conditions are considered. We develop the standard homotopy analysis method and the boundary-domain element method to solve for the unknown steady-state concentrations of reactants. The validity of the proposed methods is checked and demonstrated by numerical examples. Convergence rates are compared and the advantages and drawbacks of the proposed methods are discussed and compared to the Mathematica NDSOLVE solver. We show, that the proposed homotopy analysis method features exponential convergence rate and is highly accurate and efficient. As low as 6 terms are needed to reach error norms of 10 − 5 . Furthermore, the boundary-domain integral approach is also capable of solving the same problem very efficiently, using a very coarse computational mesh (21 nodes). [ABSTRACT FROM AUTHOR]