Diagram Of System Research Articles

Key phase diagram experiments and thermodynamic modeling of the ZnO‒B2O3, ZnO‒SiO2, and ZnO‒B2O3‒SiO2 systems

AbstractThermodynamic modeling of binary ZnO‒B2O3 and ZnO‒SiO2 systems and ternary ZnO‒B2O3‒SiO2 system were carried out based on the critical evaluation and optimization of all available phase diagram and thermodynamic property data using the CALculation of PHAse Diagram (CALPHAD) method. To resolve the inconsistency among the available phase diagram data in ternary ZnO‒B2O3‒SiO2 system, key phase diagram experiment was carried out using classical quenching method followed by electron probe micro‐analysis and X‐ray diffraction phase determination. The liquid oxide solution was described using the modified quasichemical model accounting for a short‐range ordering behavior in molten oxide solution. Thermodynamic models with optimized model parameters were used to predict the phase diagram and thermodynamic properties of the ternary systems.

From deterministic to stochastic: limits of extracting bifurcation diagrams for noisy bistable oscillators with the control-based continuation method

AbstractNoise limits the information that can be experimentally extracted from dynamical systems. In this study, we review the Control-based Continuation (CBC) approach, which is commonly used for experimental characterisation of nonlinear systems with coexisting stable and unstable steady states. The CBC technique, however, uses a deterministic framework, whereas in practice, almost all measurements are subject to some level of random perturbation, and the underlying dynamical system is inherently noisy. In order to discover what the CBC is capable of extracting from inherently noisy experiments, we study the Hopf normal form with quintic terms with additive noise. The bifurcation diagram of the deterministic core of this system is well-known, therefore the discrepancies introduced by noise can be easily assessed. First, we utilise the Step-Matrix Multiplication based Path Integral (SMM-PI) method to approximate the system’s steady state probability density function (PDF) for different intensity noise perturbations. We associate the local extrema of the resulting PDFs with limit cycles, and compare the resulting bifurcation diagram to those captured by CBC. We show that CBC estimates the bifurcation diagram of the noisy system well for noise intensities varying from small to moderate, and in practice, the amplitudes provided by CBC may be accepted as a ’best guess’ proxy for the vibration amplitudes characteristic to the near periodic solutions in a wide range of experiments.

Human Vision as A Multi-Circuit Mathematical Model of the Automated Control System

Abstract The paper contains a proposal an original, extended mathematical model of an automatic system of human vision reaction to a forcing light pulse. A comprehensive mathematical model of the vision process was proposed in the form of an equation described in the frequency (dynamics) domain. Mathematical modelling of human senses is very important. It enables better integration of automation systems with a human cooperating with them, also as an automation system. This provides the basis for reasoning based on a mathematical model instead of intuitive reasoning about human reactions to visual stimuli. A block diagram of the proposed system with five human reaction paths is given. The following can be distinguished in the scheme: the main track consisting of: the transport delay of the eye reaction, the transport delay of the afferent nerves, the inertia of the brain with a preemptive action, the transport delay of the centrifugal nerves and the inertial and transport delay of the neuromotor system. In addition, the scheme of the system includes four tracks of negative feedback of motor and force reactions: upper eyelid, lower eyelid, pupil and lens. In the proposed model, the components of each path along with their partial mathematical models are given and discussed. For each reaction path, their overall mathematical models are also given. Taking into account the comprehensive models of all five reaction paths, a complete mathematical model of the automatic system of human reaction to a forcing light impulse is proposed. The proposed mathematical model opens up many possibilities for synchronizing it with mathematical models of many mechatronics and automation systems and their research. Optimizing the parameters of this model and its synchronization with specific models of automation systems is difficult and requires many numerical experiments. This approach enables the design of automation systems that are better synchronized with human reactions to existing stimuli and the selection of optimal parameters of their operation already in the design phase. The proposed model allows, for example, accurate determination of difficulty levels in computer games. Another example of the use of the proposed model is the study of human reactions to various situations generated virtually, for example in flight simulators and other similar ones.

Hearts and minds: a community-based systems diagram exploring mental health following a cardiac event

Abstract Background/Introduction Following an acute cardiac event, individuals commonly face multiple emotional and mental health challenges. For many people, this change in their mental health will resolve over time. However, one in five will go on to develop major depressive disorder. The development of major depressive disorder is a complex co-morbidity that, if left unchecked, can increase the risk of subsequent cardiac events and mortality. Systems thinking methodology offers a novel approach to investigating factors that contribute to mental health following a cardiovascular event. Purpose This project aims to (1) unravel the complex system influencing mental health after a cardiac event and (2) pinpoint priorities for supporting individuals' mental well-being following a cardiac event. Methods Group model building workshops using Deakin University’s purpose-built STICKE software were conducted over Zoom to explore the interrelationships contributing to mental health following a cardiovascular event. Twelve participants, including consumers (n = 3) and healthcare professionals (n = 9) from across Australia, engaged in two 1.5-hour workshops. Guided by the prompt "Reflect on factors influencing a person’s mental health post-cardiac event", participants worked together to construct a systems diagram. This facilitated exploration, visual mapping, and identification of factors and priority areas influencing mental health post-cardiac event. The diagram was then analysed using the theoretical domains framework. Results The STICKE diagram developed demonstrates the interplay of various factors impacting mental health across the cardiac healthcare journey at both patient and system levels (see Figure 1). Using the theoretical domains framework, eight domains were identified: knowledge, skills of healthcare professionals, environmental context, personal context, emotional response to event and recovery, social influences, behavioural regulation, and beliefs about individual capacity. Knowledge (including health literacy and staff training), environmental context (addressing gaps in care and navigating the system), and social influences (such as social isolation) were domains that were consistently raised in the workshop (see Figure 2). Stakeholders also identified the following key priority areas: highlighting the need for additional support for staff and intervention to increase health literacy and knowledge around mental health. Conclusion(s) Supporting mental health post-cardiac events is a multifaceted challenge requiring a comprehensive community-level intervention, particularly in the initial weeks post-hospitalisation. The insights gained from this study will inform the co-design of an intervention aimed at increasing health literacy and knowledge around mental health following a cardiovascular event.

MODELING OF THE AUTOMATED COMPLEX COMPONENTS FOR SEGREGATED RESIDUES GATHERING OF OPERATIONAL PRINTING

Abstract. An overview of the printing industry primary measures regarding the balanced implementation of the sustainable development goals at the regional level was carried out. Based on the latest works analysis in the direction of the enlargement of branch waste management systems, the solutions insufficiency for the limited financial situations of small businesses is revealed, and the relevance of finding optimal means of gathering segregated waste and their temporary storage at the enterprise is shown. The criteria have been established and the stratification of typical categories of orders the operational printing has been carried out according to print run and rest volume. The requirements for the collection and storage of waste raw materials and consumables have been clarified and expanded, in particular regarding the provision of microclimatic conditions. In order to model effective business processes of pro­duction residues management, the construction of a universal complex for target cumulative of pre-segregated substrate scraps in the form of a smart container with a weighing terminal is substantiated. For flexible allocation of corporate flows, the hardware part is implemented from measuring, supervisory and communication blocks depending on their purpose in the automated microprocessor platform. The researched printing waste types the built algorithm of the life cycle of their cumulating made it possible to draw up an architectural diagram of segregator system and determine the main components hierarchy of printing waste receptacle when order manufacturing. As a result, analytical models were built and the modeling of automated complex of segregated residues gathering in operational printing was carried out based on created microcontroller system for monitoring of mass and climate control of cumulated surpluses to maintenance proper conditions their subsequent recycling.

Exploring Non-linear Dynamics: Constructing the Bifurcation Diagram of a Damped Driven Pendulum using Python

In this paper, we present a detailed analysis and construction of the bifurcation diagram for the damped-driven pendulum system. The bifurcation diagram in general presents the qualitative changes of the steady-state behavior for the pendulum. For this purpose, we implement the use of the Python programming language with the inclusion of scientific libraries. This nonlinear dynamical system is an example of a system that exhibits a chaotic regime, which is the sensitivity of its behavior to the initial conditions and the parameters of the system. We investigate the response of the system to a range of drive strengths γ applied. By changing the driving strength, the system reveals patterns of periodicity, quasi-periodic, and chaotic regimes. The critical values where it goes from regular motion to chaotic one are highlighted, offering further understanding of the mechanisms of the transitions. This study presents the use of the Python programming language for the modeling and visualization of non-dynamic systems and contributes to a deeper understanding of nonlinear oscillator dynamics.

A Combined Experimental and Computational Study on the Effect of the Reactor Configuration and Operational Procedures on the Formation, Growth and Dissociation of Carbon Dioxide Hydrate

Clathrate hydrate-based technologies are considered promising and sustainable alternatives for the effective management of the climate change risks related to emissions of carbon dioxide produced by human activities. This work presents a combined experimental and computational investigation of the effects of the operational procedures and characteristics of the experimental configuration, on the phase diagrams of CO2-H2O systems and CO2 hydrates’ formation, growth and dissociation conditions. The operational modes involved (i) the incremental (step-wise) temperature cycling and (ii) the continuous temperature cycling processes, in the framework of an isochoric pressure search method. Also, two different high-pressure PVT configurations were used, of which one encompassed a stirred tank reactor and the other incorporated an autoclave of constant volume with magnetic agitation. The experimental results implied a dependence of the subcooling degree, (P, T) conditions for hydrate formation and dissociation, and thermal stability of the hydrate phase on the applied temperature cycling mode and the technical features of the utilized PVT configuration. The experimental findings were complemented by a thermodynamic simulation model and other calculation approaches, with the aim to resolve the phase diagrams including the CO2 dissolution over the entire range of the applied (P, T) conditions.

Study and simulation of the coordination of electrical protections

In this work, an analysis of the coordination of protections of an electrical system is carried out. To do this, the ETAP software is used, which allows the modeling of each element from the single-line diagram of the electrical system. The initial conditions associated with the load level of the elements and lines due to the presence of loads at nominal values are defined. Next, a failure analysis is developed, to carry out a protection coordination study later, defining failure scenarios in different bars of the system, as well as the performance characteristics of the protections. Finally, a technical-economic analysis is carried out, considering historical data on energy consumption by the industrial plant.

Current approaches to meaningful learning that complement the construction of knowledge in the process of reading comprehension

In this work, an analysis of the coordination of protections of an electrical system is carried out. To do this, the ETAP software is used, which allows the modeling of each element from the single-line diagram of the electrical system. The initial conditions associated with the load level of the elements and lines due to the presence of loads at nominal values are defined. Next, a failure analysis is developed, to carry out a protection coordination study later, defining failure scenarios in different bars of the system, as well as the performance characteristics of the protections. Finally, a technical-economic analysis is carried out, considering historical data on energy consumption by the industrial plant.

Melting temperature and elastic constants of disordered nonstoichiometric cubic TiCy, ZrCy and HfCy carbides

Based on the analysis of phase diagrams of carbide-forming systems M–C (M = Ti, Zr, Hf), an empirical relationship is proposed between the elastic stiffness constants cij of nonstoichiometric cubic carbides of titanium, zirconium and hafnium and their melting temperature. The dependences of the melting temperatures of nonstoichiometric cubic carbides TiCy, ZrCy and HfCy on their composition in homogeneity regions are calculated using the elastic stiffness constants c11(y) and c44(y) of these carbides. The calculated maximum melting temperatures are observed for carbides ~TiC0.80, ~ZrC0.82 and ~ HfC0.94–0.95 and are equal to 3345, 3708 and 4192 K, respectively. There is a qualitative correlation between the concentration dependences of the melting temperatures Tm(y) of TiCy, ZrCy and HfCy carbides and the anisotropy of the elastic properties of these carbides.

Calculation of critical endpoints and phase diagrams of highly asymmetric binary systems

The computation of Global Phase Equilibrium Diagrams (GPED) for binary systems, including critical and three-phase equilibrium curves, is crucial for analyzing process conditions and assessing thermodynamic models. In the past two decades, algorithmic strategies and GPEC software have become essential tools. However, numerical problems can arise with the original algorithm for highly asymmetric systems, such as gases or water with heavy compounds or polymers, hindering the completion of GPED and related diagrams.This study presents an innovative calculation methodology to address these challenges. Our approach extends existing algorithms to achieve automatic GPED generation without user intervention, focusing on nearly pure phases. We apply our methodology to systems such as methane or water with heavy alkanes, and CO2 + silicones. The proposed algorithmic strategies effectively handle asymmetric systems, different types of phase behavior, and the estimation of extremely low concentrations in nearly pure phases along the vapor-liquid-liquid equilibrium curve.

Особенности построения системы экологического менеджмента организации с учетом вновь введенных национальных стандартов ГОСТ Р ИСО 14006—2022 и ГОСТ Р МЭК 62430—2023

The information on legislative documents of the Russian Federation regulating the activities of companies in the sphere of environmental management, considering environmental standards in design, has been provided. The relevance and feasibility of application of the system-structural process approach at the stage of development and implementation of the environmental management system, considering the environmental standards in design based on the standards GOST R ISO 14006—2022 and GOST R IEC 62430—2023, have been substantiated. The use of the process approach to the environmental management system development considering environmental standards in design based on the systems approach using the well-known PDCA principle has been methodologically substantiated; the basic issues of its applicability have been considered. A matrix of processes and subprocesses is compiled in accordance with the sections of GOST R ISO 14006 and the process typology as provided by ISO/TC 176/SC 2/N 544R3 (company’s management processes; processes of measurement, analysis, and improvement; key processes of resource management); the processes are ranked by their level. A model of the environmental management system has been developed considering environmental standards in design based on the process approach, Structured Analysis and Design Technique (SADT), and IDEF0 functional modeling methodology. The main context diagram of the environmental management system considering environmental standards in design in IDEF0 notation is developed. The decomposition of processes and subprocesses of the second and third levels has been completed; all their functional connections are described. The provided process modeling methodology allows reaching positive effect as to minimization of costs and time of the development of the environmental management system model, considering environmental standards in design. It has been demonstrated that the process approach applied to design of the system model of environmental management system considering environmental standards in design enables structuring the composition of processes, precise determining of input and output parameters of processes, participants of processes, resources, and ensuring process control and adjustment.

Stabilization of gels and emulsions in the ternary water/eugenol/poloxamer 407-system: Physicochemical characterization and potential application as encapsulation platforms

The ternary system water/eugenol/poloxamer 407 can form a variety of phases that are strongly influenced by the mixture composition and the thermal history of the system. In this study, we investigated the stabilization of emulsion and gel-like systems in which eugenol is encapsulated in a poloxamer 407 matrix. Our results reveal the complex interplay between poloxamer 407 and eugenol compositions in the stabilization single-phase systems at 25ºC. Increasing concentrations of poloxamer were found to incorporate higher amounts of eugenol into emulsion-like dispersions, effectively preventing coalescence and Ostwald ripening. However, high concentrations of poloxamer 407 induced gelation of these dispersions, resulting in eugenol-loaded poloxamer 407 gels. The thermal annealing of the emulsions at 65°C for 1 h followed by equilibration at room temperature allows the extension of the compositional range for the formation of homogeneous single-phase systems providing a strategy to modulate the phase diagram of the ternary system. Additionally, the encapsulation of hydrophobic pesticides in gel-like matrices was investigated, showing uniform distribution and consistent loading capacity (approximately 0.70 % w/w) across different pesticides which may contribute to facilitate the environmental distribution and efficacy of the encapsulated molecules. This research highlights the potential of eugenol/poloxamer 407-based systems as an environmentally friendly platform for the encapsulation and delivery of hydrophobic active molecules, offering a versatile solution for various applications.

Solid-liquid phase equilibria in the aqueous system containing the chlorides of potassium, ammonium, and calcium at 298.2, 323.2, and 348.2 K

In order to obtain the crystalline forms of the salts of the potassium, ammonium, calcium coexisting chloride system, the phase equilibria relationship of quaternary system K+, NH4+, Ca2+//Cl–-H2O at 298.2, 323.2, and 348.2 K was studied by isothermal dissolution equilibrium method. The solubility and density of equilibrium liquid phases of the system were experimentally determined; X-ray powder diffractometer was used to determine the compositions of the equilibrium solid phase at the quaternary invariant point. It is found that the quaternary system is a complex system at these three temperatures. The phase diagram at 298.2 K consists of three invariant points, seven univariate curves and five crystalline phase regions, forming the solid solutions (NH4Cl)x(KCl)1–x and (KCl)x(NH4Cl)1–x; while at 323.2 and 348.2 K the phase diagram consists of five invariant points, eleven univariate curves and seven crystalline phase regions, the double salts (KCl·CaCl2) and (2NH4Cl·CaCl2·3H2O), solid solutions (KCl)x(NH4Cl)1–x and (NH4Cl)x(KCl)1–x were formed. Among them, the crystalline phase region of solid solution (KCl)x(NH4Cl)1–x is the largest at three temperatures, indicating that it is the easiest to crystallize in this system. Comparing the phase diagrams of the quaternary system at 298.2, 323.2, and 348.2 K, it can be seen that the crystalline form of CaCl2 changes with the increase of temperature: CaCl2·6H2O at 298.2 K, CaCl2·2H2O at 323.2 and 348.2 K. From 323 to 348 K, the crystalline phase regions of (KCl·CaCl2) and (2NH4Cl·CaCl2·3H2O) increased gradually.

The climate change-pollution-aerobiome nexus: A 'systems thinking' mini-review.

The interrelationship between climate change, pollution and the aerobiome (the microbiome of the air) is a complex ecological dynamic with profound implications for human and ecosystem health. This mini-review explores the multifaceted relationships among these factors. By synthesising existing research and integrating interdisciplinary perspectives, we examine the mechanisms driving interactions within the climate change-pollution-aerobiome nexus. We also explore synergistic and cascading effects and potential impacts on human health (including both communicable and non-communicable diseases) and that of wider ecosystems. Based on our mini-review results, climate change influences air pollution and, independently, air pollution affects the composition, diversity and activity of the aerobiome. However, we apply a 'systems thinking' approach and create a set of systems diagrams to show that climate change likely influences the aerobiome (including bacteria and fungi) via climate change-pollution interactions in complex ways. Due to the inherent complexity of these systems, we emphasise the importance of holistic and/or interdisciplinary approaches and collaborative efforts in understanding this nexus to safeguard planetary health in an era of rapid environmental change.

Pemodelan Integration Use Case (IUC): Perancangan Use Case Diagram (UML) untuk Sistem-sistem yang Terintegrasi

Modeling use cases in software development for a system has been well-documented in literature. Today, digital business competition is becoming faster and more integrated. System or software development now not only analyzes the development of the system itself but also considers how the system can later be integrated with other systems or features in other companies' applications. Therefore, designing use case diagrams for integrated systems has become important; however, based on the author's observations, literature discussing this is still very limited. This article aims to identify and to explain the modeling of integration use cases (IUC) through discussions in the case study of school information system management, as well as to educate readers on the importance of IUC based on the correct and proper use of UML notation. This article discusses in detail the fundamental understanding of notations in depicting use case diagrams, the creation of integration use case diagrams (IUCD) for systems integrated with existing and new systems.

Phase Diagrams of a Relativistic Self-Interacting Boson System

Within the Canonical Ensemble, we investigate a system of interacting relativistic bosons at finite temperatures and finite isospin densities in a mean-field approach. The mean field contains both attractive and repulsive terms. Temperature and isospin density dependences of thermodynamic quantities are obtained. It is shown that, in the case of attraction between particles in a bosonic system, a liquid-gas phase transition develops against the background of the Bose–Einstein condensate. The corresponding phase diagrams are given. We explain the reasons for why the presence of a Bose condensate significantly increases the critical temperature of the liquid-gas phase transition compared to that obtained for the same system within the framework of Boltzmann statistics. Our results may have implications for the interpretation of experimental data, in particular, how sensitive the critical point of the mixed phase is to the presence of the Bose–Einstein condensate.

Separation and extraction of NH4Br and (K,NH4)2SO4 from 1-Bromooctane production wastewater by crystallization method

This work provides a method for the separation and extraction of bromine salts from bromine-containing wastewater by crystallization. Wastewater from the production of 1-Bromooctane is rich in potassium and bromine salts. This will allow for the recycling of chemical resources in this aqueous salt system. Based on the need for the process design of the new method, the solubility phase equilibrium of the quaternary K+,NH4+//SO42-,Br-–H2O system at 298.15 K and 323.15 K was investigated in this paper by using the isothermal dissolution equilibrium method, and the dry basis phase diagrams were plotted using the experimental data. And the equilibrium solid phase composition was determined by X-ray diffraction. At 298.15 K, the dry phase diagram of the quaternary system K+,NH4+//SO42-,Br-–H2O consists of three invariant points and five crystalline regions (K2SO4, (NH4)2SO4, (K,NH4)2SO4, (K,NH4)Br, (NH4,K)Br). At 323.15 K, there is one invariant point in the phase diagram of this quaternary system and three crystalline regions((K,NH4)2SO4, (K,NH4)Br, (NH4,K)Br). The (K,NH4)Br crystallization zone grows while the (NH4,K)Br crystallization zone decreases with increasing temperature, according to comparisons of the dry basis phase diagrams of this quaternary system at different temperatures. Crystallization zones of solid solution (K,NH4)2SO4 replaced the K2SO4 and (NH4)2SO4 single salt crystallization zones at the same time. The Pitzer model was used to calculate the solubility of this quaternary system at 298.15 K. The results showed that the experimental values were in good agreement with the calculated values. Based on the theoretical analysis of the dry phase diagram of the quaternary system K+,NH4+//SO42-,Br-–H2O, a process route for salt extraction using bromine-containing wastewater generated from the production of 1-Bromooctane was proposed and designed. The new process was experimentally verified to be technically feasible to obtain NH4Br with 99.01 % purity and (K,NH4)2SO4. The process has significant advantages, such as production safety, low input costs and no three-waste emissions.

First principles study of the structure and superconductivity of La-Ge alloys under high pressure

High pressure is a fundamental approach for discovering and developing new materials, where adjusting the pressure can induce phase transitions and novel properties, such as superconductivity. In this study, we conduct a comprehensive investigation of the structural and electronic properties of La-Ge compounds within the pressure range of 0–30 GPa by using first-principles calculations. Three new stable compounds have been identified, namely I4/mmm_La2Ge, Fd3̅m_LaGe2, and P6/mmm_LaGe5. In combination with the known structures, the pressure-component phase diagram of the La-Ge binary system is constructed. The results of electronic structure calculations indicate that all structures represented in this diagram exhibit metallic properties. The new structure Fd3̅m_LaGe2 with C15 Laves phase is predicted to be stabilized dynamically from 23 GPa up to at least 30 GPa. The calculations of superconducting properties reveal that both Fd3̅m_LaGe2 and Immm_LaGe5 are superconductors with critical temperatures of 5.9 K at 23 GPa and 6.3 K at 0 GPa, respectively. Superconductivity observed in both Fd3̅m_LaGe2 and Immm_LaGe5 can be attributed primarily to the coupling between Ge-4p electrons and phonons situated in proximity to the Fermi level. Our results indicate that phases with elevated Tc are more prevalent in compounds with a higher proportion of Ge atoms in the total density of states. These findings are expected to provide theoretical guidance for future experimental investigations of La-Ge system, facilitating the exploration of C15-type superconductors in the form of AB2.

Impact of the Sr2+-Nd3+ heterovalent isomorphism on the luminescence of orthoborates in Sr3B2O6-NdBO3 system

The phase diagram of the Sr3B2O6-NdBO3 binary system was studied. The intermediate compound Sr3Nd2(BO3)4 can be synthesized over a wide range of compositions, from 27 to 70 mol.% NdBO3, at 1200°C. The maximum luminescence of Nd in this solid solution was measured for the highest content of Sr. The partial substitution of Nd by 3 mol.% Sr in NdBO3 does not significantly affect the presence of concentration quenching. The phase exhibiting the strongest luminescence within the system is neodymium doped Sr3B2O6.