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We present a mathematical model for the slow combustion (smoldering) of a two-dimensional sheet of paper. We describe the evolution of the char region, and we investigate the effects of an orthogonal air flow on the shape of the combustion front. The mathematical formulation consists in a set of two nonlinear PDEs for the temperature and the oxygen concentrations coupled with one ODE for the cellulose concentration. The (dimensionless) problem is solved numerically by means of a spectral collocation scheme based on Chebyshev polynomials. Our results show that the Péclet and the Lewis number strongly influence the shape of the ignition front and that the advancement of the combustion front does not occur if advection and diffusion are neglected (zero Péclet and Lewis numbers). In particular we observe that the burning region and the ignition front are strongly influenced by the velocity of the airflow and by the mass and heat transport phenomena due to diffusion and advection. We shall see that the increasing of the ratio between the convective and diffusive characteristic times (Péclet number) and the decreasing of the ratio between the mass and heat diffusive characteristic times (Lewis number) have a "flattening effect" on the combustion front. [ABSTRACT FROM AUTHOR]

In this article, we present a mathematical model and numerical simulation of the coffee-ring effect on porous papers. The numerical method is based on Monte Carlo simulation. The proposed model is simple but can capture the main mechanism of coffee stain formation on porous papers. Several numerical experiments are presented to demonstrate the performance of the proposed algorithm. We can obtain the coffee-ring effect on porous papers as the computer simulation results. [ABSTRACT FROM AUTHOR]

Mathematical modeling is a high-leverage topic; it is critical to students' participation in STEM education and supports civic engagement. Until recently, research on modeling at the elementary level has been underemphasized, particularly research on supports and challenges for teachers who engage in designing authentic modeling tasks. In this study, we employed qualitative case study methods to investigate how elementary teachers designed and implemented authentic mathematical modeling tasks, with an explicit focus on how their tasks evidenced different dimensions of authenticity. We analyzed three cases of teams of elementary teachers as they developed modeling tasks connected to school and community contexts. The three cases were: 1) a student-driven modeling task related to paper and plastic waste in a school cafeteria, 2) a modeling task based on authentic situations at a community-run resource center, and 3) a modeling task focused on designing and monitoring a school community-building art project. Our cases illustrate that elementary teachers can successfully design and implement modeling activities that utilize different entry points and evidence multiple dimensions of authenticity. Furthermore, we found that the specific dimensions of authenticity may vary depending on the design supports and curriculum challenges within each context. [ABSTRACT FROM AUTHOR]

To enhance the quality and efficiency of computer-enabled generation of papers for Test for English Majors Band 8 (TEM-8), a paper generation model supported by sparrow search algorithm-genetic algorithm was studied. First, a simplified test paper generation mathematical model was set up after analyzing and studying types and characteristics of TEM-8 tasks. In the model, quantity, type, difficulty, discrimination degree, scores, exposure, and answering time of test questions were taken into consideration. To enhance the optimizing effect of the genetic algorithm for searching test questions, the traditional genetic algorithm was improved by introducing the sparrow search algorithm into the model to achieve a better crossover rate, variance rate, optimization precision, and speed of the genetic algorithm. A new sparrow search-genetic algorithm (SSA-GA) was designed, and the optimizing effect of SSA-GA was verified to be ideal through optimizing six standard test functions. Then, SSA-GA was applied to conduct experimentation with test paper generation, and comparison with traditional genetic algorithms was also made. The values of best and average fitness of SSA-GA were better than those of the traditional genetic algorithm (GA) in the paper generation. Exposure rate and success rate in TEM-8 paper generation of SSA-GA were higher than those of traditional GA in TEM-8 paper generation. Results showed that the studied SSA-GA could implement test paper generation with higher speed and better quality. [ABSTRACT FROM AUTHOR]

Howard Rachlin's widely influential behavioral economic approach to self‐control and related issues provides the model for this submission. The topic is overconsumption. Current human consumption levels are unsustainable. Explanations typically focus on societal factors, such as the seductive power of advertising and/or misguided tax policies. However, the effectiveness of these factors depends on the degree to which individuals are susceptible to the message: "consume more." Humans are not blank slates. This paper argues that how individuals frame their choices establishes the susceptibility to overconsume. According to economic theory, consumers frame their options as bundles, composed of different combinations of the available items and activities. This leads to maximizing. In experiments, participants tend to frame their options as "either‐or" choices. This leads to the matching law. Mathematical models of concurrent schedule choice procedures show that (1) the matching law implies overconsumption of the most preferred option and (2) that individuals will persist in preferring their favorite option even when doing so reduces overall reward rates. Given that the matching law better describes how individuals choose than does maximizing, the mathematical models of widely used choice procedures help explain why efforts to increase consumption have been more influential than efforts to control consumption. [ABSTRACT FROM AUTHOR]

Due to rapid temperature rise and insulation moisture, bubbles can generate in the oil-paper insulation of oil-immersed power transformers, which can reduce the dielectric strength of oil-paper insulation and even bring about the risk of insulation breakdown. In order to accurately evaluate the conditions of bubble formation, the physical process of bubble formation in oil-paper insulation is studied in this article. Considering the effects of water vaporization, gas dissolution in oil, and moisture migration on bubble formation, a bubble formation prediction model is constructed. Based on Henry’s law, the dissolution equilibrium of gas in oil is taken into consideration and the upper boundary of the initial temperature of bubble effect (ITBE) envelope is obtained in this model. Based on the moisture equilibrium in oil-paper insulation, the bubble formation process caused by the emergence and rapid evaporation of free water is analyzed, and then, the lower boundary of the ITBE envelope is obtained in this model. The model results show that the moisture content of the pressboard and the presence of free water have a great impact on ITBE. Specifically, the higher the moisture content, the lower the ITBE value. In addition, with the further increase of moisture content, the upper and lower boundaries of the ITBE envelope gradually tend to be the same. However, once free water is present on the surface of cellulose, ITBE decreases rapidly to below 120 °C. The model built in this article is of great significance to study the temperature limit of the power transformer. Hence the ITBE envelope can provide an important theoretical reference for reducing the risk of bubble formation during power transformer operation. [ABSTRACT FROM AUTHOR]

Mathematical modelling is a powerful tool in science. Causal mathematical models based on a clear picture of how key variables interact enable a deeper understanding of a given situation and provide reliable predictions. This is a classic approach in science. Unfortunately, this approach is declining in pulp and paper-related research in favour of simply reporting experimental data. The lack of a framework provided by a model diminishes the value of much experimental work. Therefore, the increased use of mathematical models is encouraged, and this approach is illustrated via several practical examples from our work. [ABSTRACT FROM AUTHOR]

The generation and distribution of furfural are significantly affected by moisture content in the insulating paper. However, the diffusion mechanism of furfural under moisture effect is not clear, hence, this study investigates the effect of moisture on the diffusion characteristics of furfural by combining macro experiment and micro molecular dynamics simulation. The simulation results demonstrate that the increased moisture content in paper accelerates the diffusion of furfural from paper to oil, which is also proved by the experimental data. Then, the results of interaction energy analysis indicate that the increase of moisture enhances the van der Waals force between oil and furfural. The present findings are expected to improve the theoretical level of furfural analysis, which will facilitate the aging evaluation of the transformer insulating paper based on furfural. [ABSTRACT FROM AUTHOR]

The space charge effect of transformer insulating paper will distort its internal electric field, and its space charge effect will be more prominent under extremely complex working conditions. At present, the micromechanism of charge transport and electric field distortion characteristics of paperboard are not clear under complex working conditions. So in this article, based on the bipolar carrier transport (BCT) model and the dynamic carrier balance model, the effects of high temperature, aging degree, moisture content, and bent degree on charges accumulation in paperboard are studied under dc high voltage by numerical simulation and the measured data needed for simulation. The results show that the higher temperature strengthens the carrier migration, deepens the injection depth of the charge, and aggravates the distortion of electric field intensity in paperboard. The more extended the aging time of paperboard, the greater the internal trap density and the deeper the trap depth, which lead to charges migration difficultly. Increasing water content in the paperboard will accelerate space charges to reach a steady state, while further increasing it will slow down this process, which is related to the shallow trap getting deeper. When the critical part of paperboard is extruded, many traps are introduced, resulting in charges accumulation seriously. The research results can reference the design of paperboard and the maintenance of transformer insulation system. [ABSTRACT FROM AUTHOR]

This article is aimed at quantifying the health condition of the power transformer insulation system through its frequency-domain dielectric characteristic by using the concept of the resistor and fractional calculus. In this regard, the dielectric model of the fractional Poynting–Thomson (PT) is proposed, and a mathematical model for parameter identification of the proposed model is presented. The shuffled frog leaping algorithm (SFLA) is used to realize the parameter identification and the fractional PT model parameters of the oil-paper samples under different insulation health conditions. The influence of moisture and aging on the fractional PT dielectric model parameters is experimentally studied. Results show that, with the increase in the water content within the insulation system, the parameters of the fractional PT model gradually decrease, and there is a strong correlation between the relaxation time and the water content. This facilitates the employment of the fractional PT model parameters to quantify the aging and moisture content of the power transformer insulation system. [ABSTRACT FROM AUTHOR]

Methanol concentration as an aging indicator can assess cellulose aging and estimate cellulose degree of polymerization (DP). Despite the advantages of methanol (MeOH), its major disadvantage is that its concentration in the oil decreases after some time. This point is called the MeOH peak in this article. Therefore, using this indicator when MeOH concentration is reduced leads to incorrect results. When using methanol, the main problem is that whenever the methanol concentration in a transformer is measured, it cannot be identified that the measured concentration belongs to the left or right side of the MeOH peak. If the measured concentration belongs to the right side of the MeOH peak, the estimated DP is incorrect. In this article, an empirical equation is established to estimate the DP value as a function of methanol concentration when methanol concentration belongs to the left side of the MeOH peak. Then, a new index called methanol peak detector index (MPDI) composed of a 2-furfural/MeOH ratio and normalized DP is presented to ensure the validity of the calculated DP value. If it is found that the measured concentration belongs to the left side of the MeOH peak, then the estimated DP by the presented equation is valid. Finally, the application of this method is verified by applying it to measurement data samples indicating the validity of the method. [ABSTRACT FROM AUTHOR]

The traditional method for transformer moisture diagnosis is to establish empirical equations between feature parameters extracted from frequency domain spectroscopy (FDS) and the transformer’s moisture content. However, the established empirical equation may not be applicable to a novel testing environment, resulting in an unreliable evaluation result. In this regard, it is acknowledged that FDS combined with machine learning is more suitable for estimating moisture content in a variety of test environments. Nonetheless, the accuracy of the estimation results obtained using the existing method is limited by the algorithm’s inability to generalize. To address this issue, we propose an AdaBoost algorithm-enhanced back-propagation neural network (BP_AdaBoost). This study creates a database by extracting feature parameters from the FDS that characterize the insulation states of the prepared samples. Then, using the BP_AdaBoost algorithm and the newly constructed database, the moisture estimation models are trained. Finally, the results of the estimation are discussed in terms of laboratory and field transformers. By comparing the proposed BP_AdaBoost algorithm to other intelligence algorithms, it is demonstrated that it not only performs better in generalization, but also maintains a high level of accuracy. [ABSTRACT FROM AUTHOR]

The Buck converter is a commonly used voltage regulator (VR) structure that supplies power to the load devices and responds to load transients. In most of the applications, the VR is controlled by voltage or current mode control, and some nonlinear approaches are used to improve the transient response which brings more complexities to the closed loop design. To achieve a fast transient response without over-regulation under a load step transient, this paper proposes a digital single-cycle regulation (SCCR) controller, which comprised a fast path, a slow path, and a neutralization path. Unlike the conventional PID control, the neutralization path of the SCCR controller is used to offset the excessive energy change in the first cycle after a load step occurs, which makes the inductor current reach its new static condition in a shorter period of time. The mathematical model of the SCCR control is established in this paper and a scanning algorithm is proposed for the design of the compensator parameters. Experimental results are presented to verify the improvement of the transient response when compared to the conventional and nonlinear PID control, the recovery time is decreased by 64.3% and 43% for load step-up and step-down when compared with nonlinear PID control. [ABSTRACT FROM AUTHOR]

The imbalance between the prevalence of patients with acute respiratory failure (ARF) and acute-on-chronic respiratory failure and the number of intensive care unit (ICU) beds requires new solutions. The increasing use of non-invasive respiratory tools to support patients at earlier stages of ARF and the increased expertise of non-ICU clinicians in other types of supportive care have led to the development of adult pulmonary intensive care units (PICUs) and pulmonary intermediate care units (PIMCUs). As in other European countries, Italian PICUs and PIMCUs provide an intermediate level of care as the setting designed for managing ARF patients without severe non-pulmonary dysfunction. The PICUs and PIMCUs may also act as step-down units for weaning patients from prolonged mechanical ventilation and for discharging patients still requiring ventilatory support at home. These units may play an important role in the on-going coronavirus disease 2019 pandemic. This position paper promoted by the Italian Thoracic Society (ITS-AIPO) describes the models, facilities, staff, equipment, and operating methods of PICUs and PIMCUs. [ABSTRACT FROM AUTHOR]

Does the materiality of a three-dimensional model have an effect on how this model operates in an exploratory way, how it prompts discovery of new mathematical results? Material mathematical models were produced and used during the second half of the nineteenth century, visualizing mathematical objects, such as curves and surfaces—and these were produced from a variety of materials: paper, cardboard, plaster, strings, wood. However, the question, whether their materiality influenced the status of these models—considered as exploratory, technical, or representational—was hardly touched upon. This article aims to approach this question by investigating two case studies: Beltrami's paper models vs. Dyck's plaster ones of the hyperbolic plane; and Chisini's string models of braids vs. Artin's and Moishezon's algebraization of these braids. These two case studies indicate that materiality might have a decisive role in how the model was taken into account mathematically: either as an exploratory or rather as a technical or pedagogical object. [ABSTRACT FROM AUTHOR]

Does the materiality of a three-dimensional model have an effect on how this model operates in an exploratory way, how it prompts discovery of new mathematical results? Material mathematical models were produced and used during the second half of the nineteenth century, visualizing mathematical objects, such as curves and surfaces—and these were produced from a variety of materials: paper, cardboard, plaster, strings, wood. However, the question, whether their materiality influenced the status of these models—considered as exploratory, technical, or representational—was hardly touched upon. This article aims to approach this question by investigating two case studies: Beltrami's paper models vs. Dyck's plaster ones of the hyperbolic plane; and Chisini's string models of braids vs. Artin's and Moishezon's algebraization of these braids. These two case studies indicate that materiality might have a decisive role in how the model was taken into account mathematically: either as an exploratory or rather as a technical or pedagogical object. [ABSTRACT FROM AUTHOR]

Harmful Sexual Behaviour (HSB) has been regularly documented as a demanding area of practice within the United Kingdom (UK). The aim of this paper is to share a practice model developed in an under-resourced inner London borough. The HSB forum is formed of a multi-agency group of professionals and runs monthly providing a platform for practitioners to seek consultation for young people they are working with who are displaying HSB's. Initial feedback for the forum from practitioners has been consistently positive and they have valued specifically the opportunity to formulate, have clear directions, and the multi-disciplinary perspective. In addition, most reported feeling empowered to implement the recommendations suggested. Given the shared vulnerability factors between those displaying HSB's and other at-risk young people such as those who are being sexually exploited, this model provides an innovative way that practitioners can be supported by multiple agencies where there is a lack of specialist services. [ABSTRACT FROM AUTHOR]

• Combined effects of extruded brick compositions with paper sludge and expanded perlite were characterized. • The use of additives in bricks has significantly affected their thermo-physical and mechanical properties. • The effects of process parameters on brick properties were investigated with a new mathematical modeling approach. • Fired brick samples showed good thermal insulation performance. • Produced exruded bricks have good potential for energy saving. Lightweight bricks produced with addition of different additive materials such as expanded perlite (EP) and recycling paper sludge (RPS) waste have been accomplished by a pug mill. Porous fired bricks were produced by using organic and inorganic additives such as paper waste and expanded perlite as pore-makers. In the experimental study, the seventeen mixture sets were prepared with Box-Behnken experimental design procedure of two additive ratios and firing temperatures. The brick samples were produced with shaping by extrusion method and firing at 850, 950 and 1050 °C for two hours after drying. Physical characteristics such as bulk density, apparent porosity and water absorption, and also, compressive strength, thermal conductivity and microstructural properties of brick samples were studied. Influences of process parameters on brick properties were investigated with a detailed neuro-regression analysis. In conclusion, the best brick composition (10 % EP + 10 %RPS by weight) in terms of thermal conductivity corresponding to acceptable mechanical properties was optimized. Accordingly, the compressive strength values of all samples are around 10 to 27 MPa. Also, the samples with high additive content (especially 10 %RPS + 5 %EP sample) exhibited the lowest thermal conductivity value (0.432 W/mK) due to the low firing temperature. [ABSTRACT FROM AUTHOR]

The aim of this paper is the development of a mathematical model to compute the optimal inventory mix to face stochastic demand at minimum cost in a two-level supply chain. The paper addresses a multi-product dynamic lot-sizing problem under stochastic demand subject to capacity and service level constraints. This model is executed to compare a Make To Order (MTO) strategy to a Vendor Managed Inventory (VMI) partnership between the supplier and their customers. Both strategies provide the demand order to be produced. A schedule of production orders is determined over the planning horizon in order to minimize the inventory holding costs of the supply chain, taking into consideration that the supplier is also responsible of initiating the replenishment orders and deliveries of their customers according to the VMI partnership. The simulation model is illustrated empirically using a real case study: a paper manufacturing company that pursues to improve customer service level and supply chain inventory costs through a proper production planning of their paper machines and a suitable VMI order replenishment schedule. [ABSTRACT FROM AUTHOR]

The accuracy of insulation defect diagnosis based on the dielectric spectrum response is severely influenced by temperature for oil-impregnated paper bushing. The dielectric loss (tan δ) mathematical model with a temperature–frequency factor to restrict the application of the frequency domain dielectric spectrum (FDS) for insulation diagnosis is not clear. In this paper, five temperatures are selected to study the frequency temperature characteristic of the FDS and polarization current for oil-impregnated paper bushing. The experimental results show that the temperature has different effects on the lower frequency (0.001 Hz–1 Hz) and higher frequency (1000 Hz–10 kHz) of FDS. With the increasing temperature, the lower frequency tan δ of 1 mHz–1 Hz shows a better pattern of exponential growth, while the higher frequency tan δ at 1 kHz–10 kHz shows the declining law with the rising temperature. With the increasing temperature, the polarization current shows a better pattern of exponential growth, while resistance obviously shows the declining law of the exponential pattern. The FDS curve of oil-impregnated paper bushings can be amended by the mathematical model of tan δ for the dielectric response on site for accuracy diagnosis. [ABSTRACT FROM AUTHOR]

We fabricated multiwalled carbon-nanotube/cellulose composite papers and measured their temperature dependences of electrical conductivity. The dependences were described with the Sheng’s fluctuation-induced tunneling (FIT) model. A possible mechanism of the electrical conduction in the composite paper was discussed in the context of the FIT model. [ABSTRACT FROM AUTHOR]

The pulp and paper sector is the fourth largest industrial sector in terms of energy use in the world. Of the numerous processes involved in paper-making by a paper machine, the dryer section is the process that consumes the largest amount of energy. A model-based method for estimating energy-saving potentials of the dryer section was put forward in the present study. It was done by four steps: establishing a mathematical model about energy consumption, determining the model parameters, benchmarking the drying performance to obtain the corresponding energy-saving measures, and estimating the energy-saving potentials by using the mathematical model. In a case study, a multi-cylinder dryer section was selected to illustrate the method. After a fundamental field test and observation, several operating problems that restricted the energy performance of paper drying were found. And then several reasonable energy-saving measures were suggested to the operators. Finally, applying the mathematic model, it was found that 0.32 ton of steam will be saved when producing 1 ton of paper in recommended operating conditions. With the designed capacity of 200,000 tons/year, the annual steam-savings will be 64,000 tons. Generally, the price of steam is 130–150 Chinese Yuan (about US$21–24) in China, and the annual economic benefits will be 8.32–9.60 million Chinese Yuan (about US$1.344–1.536 million). [ABSTRACT FROM AUTHOR]

Planning and implementing surge capacity in healthcare services is challenging. The evolving nature of viral transmission makes it difficult to predict the potential impact on the health system and the readiness of healthcare managers and professional staff in responding to system transformation and consequential impacts. This is compounded by sudden increased demands in the types of work required. Guidance for implementing targeted strategies for health systems and services should include evidence that considers the feasibility, appropriateness, meaningfulness and effectiveness of healthcare practices at both the system and organization level. This is consistent with the Joanna Briggs Institute (JBI) model of evidence synthesis and translation. Evidence-based decision-making is a core management competency for health service leadership and the mechanism for improving the quality of management decisions, and hence better service delivery, effectiveness and efficiency. Human resources are the most important asset in crisis management. Health managers must create responsive surge capacity by quantifying existent human and material resources and the shortfall needs required to meet anticipated additional demand. We believe a multifaceted approach is the key to developing systemic surge capacity within the heath sector when faced with the management of crises such as pandemics. We explore and discuss the desirability of strategies based on the JBI model of evidence synthesis and implementation with a view to encouraging the creation of registries and followup systems. We believe this will encourage the effective use of human resources including the upskilling in how future crises may be addressed. [ABSTRACT FROM AUTHOR]

The study of the dynamics of the size of a population via mathematical modelling is a problem of interest and widely studied. Traditionally, continuous deterministic methods based on differential equations have been used to deal with this problem. However, discrete versions of some models are also available and sometimes more adequate. In this paper, we randomize the Pielou logistic equation in order to include the inherent uncertainty in modelling. Taking advantage of the method of transformation of random variables, we provide a full probabilistic description to the randomized Pielou logistic model via the computation of the probability density functions of the solution stochastic process, the steady state, and the time until a certain level of population is reached. The theoretical results are illustrated by means of two examples: The first one consists of a numerical experiment and the second one shows an application to study the diffusion of a technology using real data. [ABSTRACT FROM AUTHOR]

Aim: To explore connections between spiritual metaparadigm and the nursing metaparadigm and advocate for a progressive spiritualization of nursing management. Background: Relationship between the spiritual holistic metaparadigm of love, communion and gift and the holonic nursing metaparadigm of care, relationship and practice is not completely understood. Method: The construction of a theoretical explanation on the basis of accumulated knowledge in the fields of nursing and spirituality (especially Christian spirituality) for the purpose of constructing a meaningful description. Results: Deep connectivity between the elements of both metaparadigms: love and care, communion and relationship, and gift and practice. Conclusion: The connection between the spiritual and nursing metaparadigms is real in nursing education, practice and management because of the holistic character of spirituality. In collective intentions and cultural values are the main channels of interaction between the nursing and the spiritual metaparadigms. Implications for nursing management: Spirituality influences nursing management by, among other things, (a) providing meaning and purpose; (b) promoting cohesion in health communities; (c) fostering respect for ethics; (d) stimulating innovation; (e) encouraging leadership; and (f) illuminating the workplace. [ABSTRACT FROM AUTHOR]

Pulp-and-paper mills produce various types of contaminants and a significant amount of wastewater depending on the type of processes used in the plant. Since the generated wastewaters can be potentially polluting and very dangerous, they should be treated in wastewater treatment plants before being released to the environment. This paper reviews different wastewater treatment processes used in the pulp-and-paper industry and compares them with respect to their contaminant removal efficiencies and the extent of greenhouse gas (GHG) emission. It also evaluates the impact of operating parameters on the performance of different treatment processes. Two mathematical models were used to estimate GHG emission in common biological treatment processes used in the pulp-and-paper industry. Nutrient removal processes and sludge treatment are discussed and their associated GHG emissions are calculated. Although both aerobic and anaerobic biological processes are appropriate for wastewater treatment, their combination known as hybrid processes showed a better contaminant removal capacity at higher efficiencies under optimized operating conditions with reduced GHG emission and energy costs. [ABSTRACT FROM AUTHOR]

In automata networks, it is well known that the way entities update their states over time has a major impact on their dynamics. In particular, depending on the chosen update schedule, the underlying dynamical systems may exhibit more or less asymptotic dynamical behaviours such as fixed points or limit cycles. Since such mathematical models have been used in the framework of biological networks modelling, the question of choosing appropriate update schedules has arised soon. In this note, focusing on Boolean networks, our aim is to emphasise that the adequate way of thinking regulations and genetic expression over time is certainly not to consider a wall segregating synchronicity from asynchronicity because they actually complement rather well. In particular, we highlight that specific update schedules, namely block-parallel update schedules, whose intrinsic features are still not known from a theoretical point of view, admit realistic and pertinent properties in the context of biological modelling and deserve certainly more attention from the community. [ABSTRACT FROM AUTHOR]

Paper-cutting is a traditional Chinese art, and Fuyang paper-cutting is a miracle of Chinese paper-cutting art. As Fuyang paper-cutting art is gradually promoted by artists during the historical inheritance, its traditional form has changed, a batch of new-style paper-cutting artworks have been created, Wang Xiaying is a leading figure in its inheritance. From the perspective of manifestation means and modeling language, this paper found that Wang Xiaying on the basis of inheriting traditional paper-cutting learned from other arts, applied innovative techniques to break through limitations in modeling, and realized the innovation of paper-cutting art It was concluded that traditional paper-cutting arts could only achieve sustainable development by integrating with new elements. [ABSTRACT FROM AUTHOR]

I will briefly discuss the history of research-related projects that Mark Burgin and I worked on together. I will then discuss our joint research related to the circle of sense and nonsense. One paper was entitled In a search for deeper meanings: navigating the circle of Sense and Nonsense and in turn articulating logical varieties as knowledge illuminators and the second was entitled In the Circle of Sense and Nonsense, Including A Mathematic Model of Meaning. This research represents a bridge between the media arts and sciences (my artwork) as a means of embodying ideas exploring a particular approach to meaning production and related computation, as well as Burgin's concepts related to logical varieties and mathematical models of meaning. I will refer to the full papers and links because they present a very robust and full articulation of the concepts discussed here. In this paper, I will briefly touch on the areas of research, supply short definitions, and refer to the relevant historical publications. [ABSTRACT FROM AUTHOR]

The psychometric properties of the paper–pencil and online versions of the Beliefs Toward Mental Illness Scale (BTMI) were examined in two studies with Latina/o individuals. In Study 1, 316 Latina/o participants completed the BTMI in a paper–pencil mode. The original three-factor model was found to be a poor fit model for the sample. Subsequent exploratory and confirmatory factor analyses identified a four-factor model as the best fitting model for the sample. The identified factors were Dangerousness, Social Dysfunction, Incurability, and Embarrassment. In Study 2, the identified best fit model was tested with 280 Latina/o participants who completed the BTMI online. The four-factor model had adequate fit. A series of measurement invariance tests on the fit model supported equal factor loadings, but rejected equivalent intercepts across paper–pencil and online administration methods, though partially equivalent intercepts and residuals were found. Consequently, modality-specific norms are recommended, depending on whether paper–pencil or online venues are utilized for administration. [ABSTRACT FROM AUTHOR]

The spatiotemporal arrangement of interacting populations often influences the maintenance of species diversity and is a subject of intense research. Here, we study the spatiotemporal patterns arising from the cyclic competition between three species in two dimensions. Inspired by recent experiments, we consider a generic metapopulation model comprising "rock-paper-scissors" interactions via dominance removal and replacement, reproduction, mutations, pair exchange, and hopping of individuals. By combining analytical and numerical methods, we obtain the model's phase diagram near its Hopf bifurcation and quantitatively characterize the properties of the spiraling patterns arising in each phase. The phases characterizing the cyclic competition away from the Hopf bifurcation (at low mutation rate) are also investigated. Our analytical approach relies on the careful analysis of the properties of the complex Ginzburg-Landau equation derived through a controlled (perturbative) multiscale expansion around the model's Hopf bifurcation. Our results allow us to clarify when spatial "rock-paper-scissors" competition leads to stable spiral waves and under which circumstances they are influenced by nonlinear mobility. [ABSTRACT FROM AUTHOR]

Radio stations are seriously affected by transmission line reradiation interference, but most of the existing methods for analyzing and solving reradiation interference on transmission lines focus on approximating the physical problem through mathematical models and algorithms, and it is difficult to study the correlation between transmission lines and reradiation interference in depth. This paper introduces the characteristic mode theory to study the influence factors of reradiation interference on transmission lines, which can decompose the surface induced current of transmission lines into a series of mutually orthogonal mode currents. This paper verifies the correctness of applying the MS (mode significance) value of the characteristic mode theory to analyze the reradiation interference through a simple transmission line example. Taking a line with 5 towers as an example, by analyzing the characteristic mode currents of transmission lines with different forwarding angles and linear arrangements, we not only verified that the characteristic mode currents can well characterize the reradiation interference, but also verified that the characteristic currents of different modes have a direct connection with the structure of the line, which can be applied in the process of designing or reconstructing the towers of the transmission lines, to predict the influence of different structural parameters on electromagnetic scattering, so as to optimize the tower design to reduce the reradiation interference effects and thus optimize the tower design to reduce reradiation interference. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Asynchronous temporal Boolean Networks (ATBNs) are more complex in structure and have different linear expressions compared to traditional synchronous Boolean networks. The complexity depends on the number of updated nodes. The main contribution of this paper is to propose results of synchronization and anti-synchronization problems of ATBNs. First, this paper abstracts two Temporal Boolean Networks (TBNs) into a mathematical model, and provides a linear expression of the network by means of the semi-tensor product (STP) tool. Second, based on the asynchronous updating scheme of temporal Boolean networks, we investigate the synchronization (including complete synchronization and anti-synchronization) of ATBNs, and provide two results to guarantee the synchronization and anti-synchronization. Finally, we provide two examples to verify the correctness of our theorems and corollaries. [ABSTRACT FROM AUTHOR]

This research paper explores the realm of fault detection in distributed motors through the vision of the Internet of electrical drives. This paper aims at employing artificial neural networks supported by the data collected by the Internet of distributed devices. Cross-verification of results offers reliable diagnosis of industrial motor faults. The proposed methodology involves the development of a cyber–physical system architecture and mathematical modeling framework for efficient fault detection. The mathematical model is designed to capture the intricate relationships within the cyber–physical system, incorporating the dynamic interactions between distributed motors and their edge controllers. Fast Fourier transform is employed for signal processing, enabling the extraction of meaningful frequency features that serve as indicators of potential faults. The artificial neural network based fault detection system is integrated with the solution, utilizing its ability to learn complex patterns and adapt to varying motor conditions. The effectiveness of the proposed framework and model is demonstrated through experimental results. The experimental setup involves diverse fault scenarios, and the system's performance is evaluated in terms of accuracy, sensitivity, and false positive rates. [ABSTRACT FROM AUTHOR]

In his unfinished Ad harmonicon coeleste, François Viète (1540–1603) approaches astronomical models in a purely mathematical way, analyzing the equations involved in them and suggesting new geometrical approaches, usually equivalent but simpler. After dealing with the Copernican planetary models, he develops three different lunar models. The first one describes a model geometrically similar but not identical to the Ptolemaic lunar model. The second is identical to that of Copernicus, but Viète significantly simplifies the calculation methods, and the third one is inspired by Tycho's lunar model. In a previous paper, I analyzed the first model. In this paper, I describe and analyze the second one, leaving for a future work the third one. Extending the ellipse models used by Viète for the outer planets, I also show that every model of epicycle and deferent can be replaced by a planet revolving on a rotating ellipse. [ABSTRACT FROM AUTHOR]

Background: People with intellectual disability have diverse needs and experience higher rates of diet‐related chronic disease such as type 2 diabetes compared to people without disability. However, they are infrequently included in development and implementation of interventions to address diet‐related chronic disease. The present study describes the process to plan, develop and refine the Food and Lifestyle Information Program (FLIP) culinary nutrition intervention for adults with mild‐to‐moderate intellectual disability. Methods: The project was initiated by a disability service provider and was guided by the Cook‐Ed™ model and inclusive research principles. Initially the disability service provider and academic research team members co‐designed pre‐program consultation and pilot studies, and draft program resources. Pre‐program consultation explored paid disability support worker (n = 10) perceptions of cooking and food skills, nutrition priorities and optimal program format, which guided further program drafting. Program resources and pilot study design were further developed and refined with co‐researchers with lived experience of intellectual disability who attended a pre‐pilot and then pilot study sessions as remunerated co‐facilitators. Results: Key characteristics of the FLIP intervention arising from pre‐program consultation included providing cooking task instruction in small steps, enabling participant choice in program activities, promoting an inclusive and social atmosphere, and providing paper‐based resources. Conclusions: FLIP intervention co‐design was enabled through ongoing input from the disability service provider and people with lived experience of intellectual disability. Evaluation of FLIP feasibility, acceptability and preliminary effectiveness to improve diet‐related health is underway. Highlights: An academic research team, disability service provider and people with lived experience of intellectual disability co‐designed a culinary nutrition intervention for adults with mild‐to‐moderate intellectual disabilityKey considerations for culinary nutrition programs for people with intellectual disability include providing small group practical instruction, paper‐based Easy Read recipes, providing choice and creating a social and inclusive atmosphere [ABSTRACT FROM AUTHOR]

Background: In example‐based learning, examples are often combined with generative activities, such as comparative self‐explanations of example cases. Comparisons induce heavy demands on working memory, especially in complex domains. Hence, only stronger learners may benefit from comparative self‐explanations. While static text‐based examples can be compared easily, this is challenging for transient video‐based modelling examples used in complex domains because simultaneous processing of two videos is not feasible. Objectives: To allow for such comparisons, we combined video‐based modelling examples with static representations (i.e., summarizing tables) of the observed optimal and a suboptimal solution of the problem‐solving process. A comparative self‐explanation prompt asked learners to compare the different solution approaches. Our study investigated the impact of video‐based modelling examples versus independent problem‐solving on cognitive load and problem‐solving skill development. Moreover, we investigated the effects of comparative versus sequential self‐explanation prompts, depending on learners' prior knowledge. Methods: In an experiment, 118 automotive apprentices learned a car malfunction diagnosis strategy. Apprentices were divided into three groups: (1) modelling examples with comparative self‐explanation prompts, (2) modelling examples with sequential prompts, and (3) no examples or prompts. Diagnostic knowledge and skills were assessed before and after the intervention. Cognitive load was measured retrospectively. Results and conclusions: Despite no observed effects on cognitive load, modelling examples enhanced diagnostic knowledge and diagnostic skills with scaffolds, though not independent diagnostic skills without scaffolds. The need for more practice opportunities to foster independent diagnostic skills is assumed. Additionally, comparative prompts seem promising for learners with higher prior knowledge. Takeaways: Video‐based modelling examples were more beneficial for learning than practising to apply the diagnostic strategy. Static representations allow for comparisons of video examples and comparative prompts are promising for learners with higher prior knowledge (cf. expertise‐reversal effect). Further research, especially on the effects on cognitive load, is necessary. Lay Description: What is already known about the topic?: Text and video examples that model how to solve a problem are widely used in education.Text examples often include self‐explanation prompts that ask learners to compare several examples.For video examples, such comparison prompts have seldom been investigated, because comparisons are difficult to implement for transient videos. What does this paper add?: This paper shows that video examples combined with static summaries of processes that have been shown in the video example are effective and allow for comparisons of video examples.Such comparisons seem to be more promising for learners with higher prior knowledge. Implications for practice: Practitioners could combine video examples with static summaries of the processes shown in the video examples to allow for comparisons. [ABSTRACT FROM AUTHOR]

Background: Measuring students' self‐regulation skills is essential to understand how they approach their learning tasks in order to identify areas where they might need additional support. Traditionally, self‐report questionnaires and think aloud protocols have been used to measure self‐regulated learning skills (SRL). However, these methods are based on students' interpretation, so they are prone to potential inaccuracy. Recently, there has been a growing interest in utilizing learning analytics (LA) to capture students' self‐regulated learning (SRL) by extracting indicators from their online trace data. Objectives: This paper aims to identify the indicators and metrics employed by previous studies to measure SRL in higher education. Additionally, the study examined how these measurements were validated. Methods: Following the protocol of Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA), this study conducted an analysis of 25 articles, published between 2015 and 2022, and sourced from major databases. Results and Conclusions: The results showed that previous research used a variety of indicators to capture learners' SRL. Most of these indicators are related to time management skills, such as indicators of engagement, regularity, and anti‐procrastination. Furthermore, the study found that the majority of the reviewed studies did not validate the proposed measurements based on any theoretical models. This highlights the importance of fostering closer collaboration between learning analytics and learning science to ensure the extracted indicators accurately represent students' learning processes. Moreover, this collaboration can enhance the validity and reliability of data‐driven approaches, ultimately leading to more meaningful and impactful educational interventions. Lay Description: What is already known about this topic?: Measuring students' self‐regulation skills is essential for understanding their learning approaches and identifying areas requiring further support.Traditionally, questionnaires and interviews have been used to measure learners' self‐regulation; however, these methods rely on students' own views, which can sometimes be unreliable.Recently, there has been more interest in using learning analytics to measure students' self‐regulation based on data extracted from their online activities. What this paper adds?: This paper systematically analyses how previous studies used learning analytics to measure students' self‐regulation in higher education.It examines how these measurements were validated. Implications for practise and/or policy: More collaboration is needed between researcher in learning science and learning analytics is essential to ensure that the metrics and methods developed are not only theoretically sound but also practically relevant. This collaboration ultimately contributes to the design of enhanced learning experiences and outcomes. [ABSTRACT FROM AUTHOR]

The primary goal of the paper is to monitor the health of the spindle in machine tools to ensure optimal performance and reduce costly downtimes. Spindle health monitoring is essential to detect wear and cracks in spindle bearings, which can be challenging due to their gradual development and hidden locations. The proposed approach combines physics-based modeling and data-driven techniques to monitor spindle health effectively. In Part I and Part II of the paper, mathematical models of bearing faults and spindle imbalance are integrated into the digital model of the spindle. This allows for simulating the operation of the spindle both with and without faults. The integration of fault models enables the generation of vibrations at sensor locations along the spindle shaft. The generated vibration data from the physics-based model are used to train a recurrent neural network-based (RNN) fault detection algorithm. The RNN learns from the labeled vibration spectra to identify different fault conditions. Bayesian optimization is used to automatically tune the hyperparameters governing the accuracy and efficiency of the learning models during the training process. The RNN classifiers are further fine-tuned using a small set of experimentally collected data for the generalization of the model on real-world data. Once the RNN classifier is trained, it can distinguish between different types of damage and identify their specific locations on the spindle assembly. The proposed algorithms achieved an accuracy of 98.43% on experimental data sets that were not used in training the network. [ABSTRACT FROM AUTHOR]

This paper introduces a novel three‐phase grid‐tied multilevel inverter (MLI) topology that employs a basic unit per phase, yielding a symmetrical configuration capable of generating five‐level output voltage and an asymmetrical configuration producing seven‐level and nine‐level output voltages. The generalization of the proposed MLI is presented in terms of the number of modules (M) and output levels (L). A comprehensive comparative analysis of the proposed MLI topology against existing configurations is presented for both symmetric and asymmetric cases. The switching devices in the MLI are controlled using the in‐phase disposition level shift PWM (IPD‐LSPWM) technique. The synchronization of the grid‐tied MLI is addressed by considering the uncertainties in grid and load parameters at the point of common coupling (PCC). To achieve synchronization, a PLL‐less grid voltage‐ modulated direct power control (GVM‐DPC) technique is implemented. To mitigate the delay associated with PLL, a GVM‐DPC based on the stationary reference frame (SRF) is applied. This paper also includes mathematical modelling of GVM‐DPC without PLL and the design of an LCL filter. A simulation model of a 15‐kVA, three‐phase, nine‐level grid‐tied MLI is developed in MATLAB/Simulink and tested under both steady‐state and dynamic conditions. The proposed controller's performance is evaluated under the load variations and sudden changes in available power from the distributed generator (DG). Robustness is tested under adverse conditions such as voltage sag/swell at the PCC. Furthermore, the system is implemented in the OPAL‐RT OP4510 real‐time simulator, and the results are validated to confirm the effectiveness and robustness of the proposed grid‐tied MLI. [ABSTRACT FROM AUTHOR]

This paper develops a new method for analyzing the relationship between a set of points and another single point, the latter of which we call a reference point. This relationship has been discussed in various academic fields, such as geography, criminology, and epidemiology. Analytical methods, however, have not yet been fully developed, which has motivated this paper. Our method reveals how the number of points varies by the distance from a reference point and by direction. It visualizes the spatial pattern of points in relation to a reference point, describes the point pattern using mathematical models, and statistically evaluates the difference between two sets of points. We applied the proposed method to analyze the spatial pattern of the climbers of Mt. Azuma, Japan. The result gave us useful and interesting findings, indicating the method's soundness. [ABSTRACT FROM AUTHOR]

This paper presents a method for determining the transmission efficiency of a gear reducer. The proposed method contains an identification theory to derive a dynamical model of motors. Using the identification theory, we propose a method to measure the torque transmission efficiency of the gear reducer. The identification theory is derived from the error between input and output data of the mathematical model of a target plant and actual time series data of the plant by an experiment. The dynamic characteristics of the gear reducer are calculated by identification theory for a system installing the motors. The target plant means a motor or a combined system consisting of the motor and the gear reducer. We discuss the torque constant as one parameter that determines motor characteristics. The torque constant value of the motor can be determined using the identification theory. Then, the torque transmission efficiency of the gear reducer can be decided by the torque constant value. In this paper, we first explain the algorithm of the identification theory, second discuss the results of identifying the motor torque constant, and finally examine the transmission efficiency of the gear reducer in the experiment. [ABSTRACT FROM AUTHOR]

This paper reviews current numerical developments for atmospheric modelling. Numerical atmospheric modelling now looks back to a history of about 70 years after the first successful numerical prediction. Currently, we face new challenges, such as variable and adaptive resolution and ultra-highly resolving global models of 1 km grid length. Large eddy simulation (LES), special applications like the numerical prediction of pollution and atmospheric contaminants belong to the current challenges of numerical developments. While pollution prediction is a standard part of numerical modelling in case of accidents, models currently being developed aim at modelling pollution at all scales from the global to the micro scale. The methods discussed in this paper are spectral elements and other versions of Local-Galerkin (L-Galerkin) methods. Classic numerical methods are also included in the presentation. For example, the rather popular second-order Arakawa C-grid method can be shown to result as a special case of an L-Galerkin method using low-order basis functions. Therefore, developments for Galerkin methods also apply to this classic C-grid method, and this is included in this paper. The new generation of highly parallel computers requires new numerical methods, as some of the classic methods are not well suited for a high degree of parallel computing. It will be shown that some numerical inaccuracies need to be resolved and this indicates a potential for improved results by going to a new generation of numerical methods. The methods considered here are mostly derived from basis functions. Such methods are known under the names of Galerkin, spectral, spectral element, finite element or L-Galerkin methods. Some of these new methods are already used in realistic models. The spectral method, though highly used in the 1990s, is currently replaced by the mentioned local L-Galerkin methods. All methods presented in this review have been tested in idealized numerical situations, the so-called toy models. Waypoints on the way to realistic models and their mathematical problems will be pointed out. Practical problems of informatics will be highlighted. Numerical error traps of some current numerical approaches will be pointed out. These are errors not occurring with highly idealized toy models. Such errors appear when the test situation becomes more realistic. For example, many tests are for regular resolution and results can become worse when the grid becomes irregular. On the sphere no regular grids exist, except for the five derived from Platonic solids. Practical problems beyond mathematics on the way to realistic applications will also be considered. A rather interesting and convenient development is the general availability of computer power. For example, the computational power available on a normal personal computer is comparable to that of a supercomputer in 2005. This means that interesting developments, such as the small sphere atmosphere with a resolution of 1 km and a spherical circumference between 180 and 360 km are available to the normal owner of a personal computer (PC). Besides the mathematical problems of new approaches, we will also consider the informatics challenges of using the new generation of models on mainframe computers and PCs. [ABSTRACT FROM AUTHOR]

Background: Competent clinical reasoning forms the foundation for effective and efficient clinical swallowing examination (CSE) and consequent dysphagia management decisions. While the nature of initial CSEs has been evaluated, it remains unclear how new information gathered by speech–language therapists (SLTs) throughout a patient's acute‐care journey is integrated into their initial clinical reasoning and management processes and used to review and revise initial management recommendations. Aims: To understand how SLTs' clinical reasoning and decision‐making regarding dysphagia assessment and management evolve as patients transition through acute hospital care from referral to discharge. Methods & Procedures: A longitudinal, qualitative approach was employed to gather information from two SLTs who managed six patients at a metropolitan acute‐care hospital. A retrospective 'think‐aloud' protocol was utilized to prompt SLTs regarding their clinical reasoning and decision‐making processes during initial and subsequent CSEs and patient interactions. Three types of concept maps were created based on these interviews: a descriptive concept map, a reasoning map and a hypothesis map. All concept maps were evaluated regarding their overall structure, facts gathered, types of reasoning engaged in (inductive versus deductive), types of hypotheses generated, and the diagnosis and management recommendations made following initial CSE and during subsequent dysphagia management. Outcomes & Results: Initial CSEs involved a rich process of fact‐gathering, that was predominantly led by inductive reasoning (hypothesis generation) and some application of deductive reasoning (hypothesis testing), with the primary aims of determining the presence of dysphagia and identifying the safest diet and fluid recommendations. During follow‐up assessments, SLTs engaged in increasingly more deductive testing of initial hypotheses, including fact‐gathering aimed at determining the tolerance of current diet and fluid recommendations or the suitability for diet and/or fluid upgrade and less inductive reasoning. Consistent with this aim, SLTs' hypotheses were focused primarily on airway protection and medical status during the follow‐up phase. Overall, both initial and follow‐up swallowing assessments were targeted primarily at identifying suitable management recommendations, and less so on identifying and formulating diagnoses. None of the patients presented with adverse respiratory and/or swallowing outcomes during admission and following discharge from speech pathology. Conclusions & Implications: Swallowing assessment and management across the acute‐care journey was observed as a high‐quality, patient‐centred process characterized by iterative cycles of inductive and deductive reasoning. This approach appears to maximize efficiency without compromising the quality of care. The outcomes of this research encourage further investigation and translation to tertiary and post‐professional education contexts as a clear understanding of the processes involved in reaching diagnoses and management recommendations can inform career‐long refinement of clinical skills. WHAT THIS PAPER ADDS: What is already known on the subject: SLTs' clinical reasoning processes during initial CSE employ iterative cycles of inductive and deductive reasoning, reflecting a patient‐centred assessment process. To date it is unknown how SLTs engage in clinical reasoning during follow‐up assessments of swallowing function, how they assess the appropriateness of initial management recommendations and how this relates to patient outcomes. What this paper adds to the existing knowledge: Our longitudinal evaluation of clinical reasoning and decision‐making patterns related to swallowing management in acute care demonstrated that SLTs tailored their processes to each patient's presentation. There was an emphasis on monitoring the suitability of the initial management recommendations and the potential for upgrade of diet or compensatory swallowing strategies. The iterative cycles of inductive and deductive reasoning reflect efficient decision‐making processes that maintain high‐quality clinical care within the acute environment. What are the potential or actual clinical implications of this work?: Employing efficient and high‐quality clinical reasoning is a hallmark of good dysphagia practice in maximizing positive patient outcomes. Developing approaches to understanding and making explicit clinical reasoning processes of experienced clinicians may assist SLTs of all developmental stages to provide high standards of care. [ABSTRACT FROM AUTHOR]

This paper introduces an autonomous robot designed for in-pipe structural health monitoring of oil/gas pipelines. This system employs a 3D Optical Laser Scanning Technical Vision System (TVS) to continuously scan the internal surface of the pipeline. This paper elaborates on the mathematical methodology of 3D laser surface scanning based on dynamic triangulation. This paper presents the mathematical framework governing the combined kinematics of the Mobile Robot (MR) and TVS. It discusses the custom design of the MR, adjusting it to use of robustized mathematics, and incorporating a laser scanner produced using a 3D printer. Both experimental and theoretical approaches are utilized to illustrate the formation of point clouds during surface scanning. This paper details the application of the simple and robust mathematical algorithm RANSAC for the preliminary processing of the measured point clouds. Furthermore, it contributes two distinct and simplified criteria for detecting defects in pipelines, specifically tailored for computer processing. In conclusion, this paper assesses the effectiveness of the proposed mathematical and physical method through experimental tests conducted under varying light conditions. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to discuss heuristics, guided by Parse's (2021a) community model, to understand how health policies emerge from the unique values and beliefs of community constituents. Within this paper, there is a discussion about heuristics, health policy, Parse's humanbecoming paradigm, and policy implications reflected upon with the change concepts of the humanbecoming community model. [ABSTRACT FROM AUTHOR]

In order to fulfill the practical application demands of precisely localizing underwater vehicles using passive electric field localization technology, we propose a scalar-potential-based method for the passive electric field localization of underwater vehicles. This method is grounded on an intelligent differential evolution algorithm and is particularly suited for use in three-layer and stratified oceanic environments. Firstly, based on the potential distribution law of constant current elements in a three-layer parallel stratified ocean environment, the mathematical positioning model is established using the mirror method. Secondly, the differential evolution (DE) algorithm is enhanced with a parameter-adaptive strategy and a boundary mutation processing mechanism to optimize the key objective function in the positioning problem. Additionally, the simulation experiments of the current element in the layered model prove the effectiveness of the proposed positioning method and show that it has no special requirements for the sensor measurement array, but the large range and moderate number of sensors are beneficial to improve the positioning effect. Finally, the laboratory experiments on the positioning method proposed in this paper, involving underwater simulated current elements and underwater vehicle tracks, were carried out successfully. The results indicate that the positioning method proposed in this paper can achieve the performance requirements of independent initial value, strong anti-noise capabilities, rapid positioning speed, easy implementation, and suitability in shallow sea environments. These findings suggest a promising practical application potential for the proposed method. [ABSTRACT FROM AUTHOR]

The class of generalized S D D 1 (G S D D 1 ) matrices is a new subclass of H -matrices. In this paper, we focus on the subdirect sum of G S D D 1 matrices, and some sufficient conditions to ensure that the subdirect sum of G S D D 1 matrices with strictly diagonally dominant (S D D) matrices is in the class of G S D D 1 matrices are given. Moreover, corresponding examples are given to illustrate our results. The class of generalized matrices is a new subclass of -matrices. In this paper, we focus on the subdirect sum of matrices, and some sufficient conditions to ensure that the subdirect sum of matrices with strictly diagonally dominant matrices is in the class of matrices are given. Moreover, corresponding examples are given to illustrate our results. [ABSTRACT FROM AUTHOR]

Economic globalization and the rapid development of the Internet make logistics systems more and more diversified, people and enterprises have greatly increased their requirements for logistics systems, and fourth party logistics has received more and more attention from people and related enterprises. In order to further study the routing problem under uncertain stochastic environments, this paper considers the fourth party logistics routing problem from a single manufacturer to multiple distributors with uncertain times and random supplies under the complete information symmetry scenario and symmetric transportation volume decision space. Then, an uncertain stochastic programming model is established with the minimum total cost as its core objective, and the total transportation time, manufacturer's supply, and distributor's demand as constraints. In order to solve the optimal path of the above problems, this paper transforms the uncertain stochastic programming model into a classical mathematical programming model based on the distribution functions of uncertain time and random supply. Finally, two numerical examples are given to verify the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]