Wagner Model Research Articles

Discretization of Thin-Walled Sections with Variable Wall Thickness

At the stage of designing thin-walled aircraft structures, to simplify calculations, their cross sections are idealized. To do this, the section with the skin and the longitudinal elements reinforcing it is replaced (when determining normal stresses) by a discrete one, consisting of concentrated areas at characteristic points. In this case, the equality of the moments of inertia of the initial and discrete sections is preserved. Such idealization is used in the calculation of thin-walled rods for normal and shear stresses (Wagner model). For sections consisting of a system of rectangular strips of constant thickness, discretization allows to set approximate values of normal and shear stresses and accurately find the locations of the singular points of the bending center (in an open contour) and the center of rigidity (in a closed one). The discrete model of a strip consists of three lumped areas: two at the edges and one in the center. The paper proposes to extend the discrete model to sections in which the skin thickness changes according to a linear law. In addition to the rectangular strip, it is possible to use elongated triangles and trapezoids, replaced by three and four concentrated areas, respectively. The possibility of using a discrete model for calculating some thin-walled sections of open and closed contours is considered. The section of an open contour is studied - the problem of transverse bending without torsion of a channel having flanges with a linearly variable thickness. Differences in the flows of tangential forces calculated from the exact and discrete models are shown. The coincidence of the results in determining the position of the bending center according to two models was established. When studying the application of a discrete model to a closed contour, its simplified option is proposed. The problem of transverse bending without torsion and finding the center of rigidity in a section with a contour line in the form of a trapezoid with front and rear walls of constant thickness and upper and lower skins and a similar section with a contour in the form of a rectangle was considered. Differences in the flows of tangential forces calculated by exact and discrete models are established. For a closed section in the form of a rectangle, the decrease in the moment of inertia for torsion due to the redistribution of material in the cross section was studied separately. It has been established that when finding the position of the center of rigidity, the discrepancy between the results of the exact and discrete models in sections with geometric parameters close to real ones was less than 1% for a rectangular contour, and 4% for a trapezoidal contour. The results indicate the possibility of extending the application of the discrete model of thin-walled cross section to the design calculations of thin-walled rods with variable skin thickness, representing practical structures.

Innovative Nanostructuring of Li–Zn ferrite/graphene composites with tunable properties

The Li-ferrite and graphene oxide (GO) nanocomposites, denoted as (Li0.5-x/2ZnₓFe2.5-x/2O4: x = 0.25), were produced through ultrasonication. The wet method generated Li-ferrite, while the Hummers' method synthesized the GO. X-ray diffraction (XRD) was used to validate the development of Li-ferrite and GO in the nanocomposites. The dimensions of the crystal were determined between 41 and 52 nm, and the porosity of the composites increased with the higher quantity of GO. The scanning electron micrographs (SEM) of ferrites illustrated the formation of uniform and well-defined grains with consistent shapes, exhibiting properties well-suited for effective microwave absorption. The electrical resistance of spinel ferrite was measured at approximately 3.34 × 1011 Ω-cm and significantly lowered as the fraction of GO increased at ambient temperature. As per Maxwell Wagner's model, the electrical permittivity exhibited interfacial polarization with distinct real and imaginary components. The AC conductivity exhibited a positive correlation with the GO content due to the conductive properties of GO and the improved charge hopping mechanism. The frequency exponent parameter's value falls from 0.36 to 0.95 b y the Jonscher's Power law. The magnetic susceptibility of all the samples exhibited a progressive decrease as the temperature increased. The choice of using lithium-based ferrite as filler is made to strengthen the ferrite/GO composites and improve their magnetic and electrical properties. This is undertaken to harness these composites for high-frequency applications, such as their use as microwave absorbers in microwave devices.

A High-Efficiency Theorical Model of Von Karman–Generalized Wagner Model–Modified Logvinovich Model for Solving Water-Impacting Problem of Wedge

The water-impacting behavior of a wedge is often studied in the slamming phenomenon of ships and aircraft. Many scholars have proposed theoretical models for studying the water-impacting problem of a wedge, but these models still have some shortcomings. This study combines Von Karman’s method, the Generalized Wagner Model (GWM), and Modified Logvinovich Model (MLM) to establish a converged theoretical Von Karman-GWM-MLM (VGM) model. The VGM model utilizes added mass to replace the fluid influence, which is derived from the velocity potential and boundary conditions. Considering the influence of impulse, the velocity is determined by the momentum theorem. Subsequently, the pressure, resultant force, and acceleration of the wedge can be calculated. By comparing with the published test data of other scholars, it is found that the velocity, acceleration, pressure, and force of the wedge obtained by the VGM model reached a consensus with experiments. The validity and accuracy of the VGM model are also verified. The efficiency and accuracy of problem-solving are both balanced when using the VGM model. The establishment of the VGM model is significant for solving water-impacting problems related to wedges.

Structural and dielectric characteristics of doped nickle oxide polyaniline composites

ABSTRACT The PANI-NiO composites were synthesized by employing an in situ chemical polymerization technique, with varying weight percentages of NiO dopant (PANI-5%NiO and PANI-10%NiO). Additionally, AC conductivity, dielectric constant and dielectric loss were investigated within a frequency range from 20 Hz to 1 MHz. XRD confirmed the phase purity and high crystallinity. SEM reveals the granular shape with a porous surface. In addition, the incorporation of NiO with different concentrations influences the composite’s dielectric properties. All samples exhibited frequency-dependent dielectric properties in line with the Maxwell–Wagner model. Notably, the AC conductivity of PANI-10% NiO composite increased as the frequency increased, this behaviour was certified with Jonscher’s power law. The I–V characteristics confirm the ohmic nature of all synthesized samples. Therefore, the potential of PANI and PANI-NiO composites, as efficient dielectric materials, has been explored and can be useful for device applications in diverse fields.

A provably masked implementation of BIKE Key Encapsulation Mechanism

BIKE is a post-quantum key encapsulation mechanism (KEM) selected for the 4th round of the NIST's standardization campaign. It relies on the hardness of the syndrome decoding problem for quasi-cyclic codes and on the indistinguishability of the public key from a random element, and provides the most competitive performance among round 4 candidates, which makes it relevant for future real-world use cases. Analyzing its side-channel resistance has been highly encouraged by the community and several works have already outlined various side-channel weaknesses and proposed ad-hoc countermeasures. However, in contrast to the well-documented research line on masking lattice-based algorithms, the possibility of generically protecting code-based algorithms by masking has only been marginally studied in a 2016 paper by Chen et al. in SAC 2015. At this stage of the standardization campaign, it is important to assess the possibility of fully masking BIKE scheme and the resulting cost in terms of performances. In this work, we provide the first high-order masked implementation of a code-based algorithm. We had to tackle many issues such as finding proper ways to handle large sparse polynomials, masking the key-generation algorithm or keeping the benefit of the bitslicing. In this paper, we present all the gadgets necessary to provide a fully masked implementation of BIKE, we discuss our different implementation choices and we propose a full proof of masking in the Ishai Sahai and Wagner (Crypto 2003) model. More practically, we also provide an open C-code masked implementation of the key-generation, encapsulation and decapsulation algorithms with extensive benchmarks. While the obtained performance is slower than existing masked lattice-based algorithms, we show that masking at order 1, 2, 3, 4 and 5 implies a performance penalty of x5.8, x14.2, x24.4, x38 and x55.6 compared to order 0 (unmasked and unoptimized BIKE). This scaling is encouraging and no Boolean to Arithmetic conversion has been used.

A Prediction Model of Evaporation Behavior of Nickel-Based Superalloy in Electron Beam Melting

The electron beam melting technique has emerged as a novel refining technology extensively employed for alloy purification due to its advantages of effectively eliminating volatile impurities and non-metallic inclusions. However, a drawback associated with the melting process is the evaporation of alloy elements, which results in an uncontrollable alloy composition. In this paper, Wagner model is used to calculate and study the evaporation behavior. of nickel-based superalloy, and the database of infinite dilution activity coefficient and interaction coefficient of nickelbased superalloy has been established. The results show that the model can well predict the composition of electron beam melting superalloy, establish the relationship between electron beam melting power and temperature, and predict the composition of several groups of DZ125 alloys after melting with different power, which is in consistent with the experimental results. This model is of guiding significance for electron beam melting of nickel-based superalloy.

Structure, dielectric and magnetic properties of hydrothermally synthesized Sn1−x Fe x O2 nanoparticles

Abstract Sn1−x Fe x O2 (x = 0, 1, 2, 3, and 4 %) of the diamagnetic/ferromagnetic phase were synthesized by the conventional hydrothermal method. X-ray diffraction spectra confirm that all the samples have a tetragonal structure. Electronic distribution over the unit cell of Sn1−x Fe x O2 showed the dependence of electronic density on the x. The crystallite size of the obtained samples was in the range of 42–72 nm. Impedance spectroscopy was employed to investigate the variation of the electrical impedance and some related parameters as frequency functions in the range of 75 k Hz–10 MHz at room temperature. The dielectric behavior was explained using the Maxwell–Wagner model of interfacial polarization. The ac conductivity results were used to evaluate the maximum barrier height, the minimum hopping distance, and the density of the localized states at the Fermi level. The effect of adding the iron ion into the tin dioxide compound was apparent, as the electrical and magnetic properties as well as the morphology were affected, although the crystal structure phase still has the same tetragonal crystal system for the different iron concentration (Fe from x = 0 up to x = 0.04) with slight variation in the lattice constants. The magnetic measurements illustrated that the Fe-doped SnO2 nanoparticles exhibit ferromagnetic ordering at room temperature. Variation of the Fe content affects the ferromagnetic characteristics of the samples.

Probing the impact of Ba on properties of ZnO at the nanoscale: optical, dielectric and antibacterial activity evolution

The sol–gel dip coating technique was used to manufacture undoped and Barium doped zinc oxide thin films. Doping is extensively used to refine semiconductor properties. Without and with varying ratios of Ba 1–9 wt% dopant, ZnO thin films have been manufactured. The effect of Ba on the dielectric, structural, antibacterial, optical and morphological characteristics of ZnO was investigated. The optical properties demonstrate that the bandgap of the pure ZnO thin film is higher than that of Ba-doped ZnO films, which is beneficial for improving solar cell performance. According to the XRD data, all films of ZnO have hexagonal wurtzite structures According to XRD structural analysis; the incorporation of Ba lowers the crystallinity of ZnO thin films by reducing the crystallite size. The Ba doping changes the surface roughness and morphology. The hopping process defines the dielectric characteristics that follow Koop’s theory as well as the Maxwell–Wagner model. A lower dielectric constant makes it ideal for high-frequency devices. These films exhibit ferromagnetism. Barium-doped zinc oxide photocatalyst could successfully decompose methylene blue dye by making it suitable for wastewater treatment. Ba doping effectively kills both gram-negative and gram-positive bacteria. They have antimicrobial applications in the food industry and biomedicine.

Novel Ni–Co-based superalloys with high thermal stability and specific yield stress discovered by directed energy deposition

We report on the rapid alloy screening of Ni–Co–Ti–Al–Mo superalloys with high thermal stability and specific yield stress by means of directed energy deposition. A laser directed energy deposition, a specific type of additive manufacturing, was employed using multiple powder feeders and elemental powders. Fifty superalloys of different compositions were deposited and the heat-treated microstructure and γ' solvus temperature were examined. The 43Ni–38Co–9Ti–6Al–4Mo superalloy (atomic percent composition) exhibited a uniform γ/γ' microstructure and a γ' solvus temperature of 1202°C. The beneficial properties of the superalloy were also found in the cast superalloy of identical composition. The cast superalloy exhibited a thermally stable γ/γ' microstructure with cuboidal γ' precipitates even after long-term aging heat treatments at 800°C, 900°C, and 1000°C up to 500 h. The γ'-coarsening mechanism was evaluated based on the Lifshitz–Slyozov–Wagner model and the trans-interface diffusion-controlled model. A transition between these two mechanisms was observed with an increase in aging temperature. Atom probe tomography analyses revealed that the sluggish interface diffusion of Co and corresponding reduction of the interfacial energy induced the transition of the γ'-coarsening mechanism. Moreover, the cast superalloy showed an enhanced specific yield stress attributed to its exceptionally low alloy density of 7.61 g/cm3.

Superradiance and solids: Reduced description method

Spontaneous ordering in a system of excited emitters with a powerful short radiation pulse predicted by Dicke attracted the great attention of scientists for decades as a bright example of the nontrivial behavior of a nonequilibrium system. The Bogolyubov reduced description method has some advantages and provides new possibilities in the theoretical investigation of the Dicke process. The paper presents the authors’ results of modeling such processes concerning both optical ones in the presence of crystal lattice influence and acoustic superradiance, which is possible in solids. The right choice of reduced description parameters allows the account of atom motions (phonons), cavity influence, and excitations in the emitter system (excitons) in the electromagnetic radiation process. The mathematical analogy between the Dicke system and a spin system in a magnetic field opens the way to applying the reduced description technique to acoustic phenomena previously investigated with the boson variable elimination method. Such a new approach to superradiance in crystals with paramagnetic impurities and with competing mechanisms of relaxation (Wagner model) is outlined. Acoustic superradiance is discussed in connection with the problem of structural phase transitions.

Taking into account the influence of correlations on the system dynamics in the reduced description method

A complex of issues related to using the Peletminsky–Yatsenko model for the study of non-equilibrium processes is investigated. The problems are associated with the inability of performing the calculation of necessary averages when system states are described by a new, wider set of reduced description parameters, in particular, fluctuations. A matter system interacting with a non-equilibrium system of bosons is considered. The substance is described by two reduced description parameters η1 , η2 and calculations with the quasi-equilibrium statistical operator corresponding to these parameters are technically impossible; at the same time, the calculations can be performed with such operator in the case of the only parameter η1 . Overcoming this problem by considering only small values δη2 of the other reduced description parameter is proposed. An exact definition of δη2 is given, and the theory of perturbations by powers δη2 is developed for the calculation of the initial quasi-equilibrium statistical operator with accuracy up to second-order contributions. Since all further averages are calculated only with the named operator including only η1 , the simplified calculation procedure is carried out for it.On this basis, the theory of non-equilibrium processes in the system of two-level emitters interacting with the boson field is developed. The emitter system is described by excitation degree η1 and the value of emitter correlations η2. The system is considered as a system of spins. The mathematically identical Dicke model describing superradiance and Wagner model introduced for the analogous acoustic phenomenon description are studied. The quasi-equilibrium statistical operator calculation is constructed.

Kinetics in low-temperature-isothermal oxidation of tungsten carbide under different humidity conditions

The isothermal oxidation experiments of tungsten carbides (WC) were carried out at levels of inequality in relative humidity (RH) levels and below 200 °C. Evaluated resistivity fluctuations and structural transformations during the low-temperature corrosion process were detected. In this paper, we present a detailed investigation into the resistivity behavior of WC under varying humidity conditions. Our innovative approach enabled us to witness a rapid decrease in resistivity under conditions of 85 % RH and 85 °C, from 0.00374 Ω-cm to 0.00177 Ω-cm, followed by a stable linear increase after 0.7 h at a constant rate of 0.000924 Ω-cm/h. Notably, a clear correlation between humidity levels and resistance change rates was found, where higher humidity led to faster resistivity changes. In sharp contrast, a resistivity change rate of less than 5 % under the conditions of water and oxygen independently was observed. The low-temperature oxidation mechanism of WC was described by XRD and XPS spectra. Moreover, the Nernst-Einstein equation and Wagner's model are used to establish the relationship between resistivity and oxidation degree for analyzing and predicting the reaction kinetics and oxidation behavior, indicating that the oxidation degree of WC increased logarithmically with oxidation time.

A series of unfortunate events: Do those who catastrophize learn more after negative outcomes?

AbstractCatastrophizing is a transdiagnostic construct that has been suggested to precipitate and maintain a multiplicity of psychiatric disorders, including anxiety, depression, post‐traumatic stress disorder, and obsessive‐compulsive disorder. However, the underlying cognitive mechanisms that result in catastrophizing are unknown. Relating reinforcement learning model parameters to catastrophizing may allow us to further understand the process of catastrophizing. Using a modified four‐armed bandit task, we aimed to investigate the relationship between reinforcement learning parameters and self‐report catastrophizing questionnaire scores to gain a mechanistic understanding of how catastrophizing may alter learning. We recruited 211 participants to complete a computerized four‐armed bandit task and tested the fit of six reinforcement learning models on our data, including two novel models which both incorporated a scaling factor related to a history of negative outcomes variable. We investigated the relationship between self‐report catastrophizing scores and free parameters from the overall best‐fitting model, along with the best‐fitting model to include history, using Pearson's correlations. Subsequently, we reassessed these relationships using multiple regression analyses to evaluate whether any observed relationships were altered when relevant IQ and mental health covariates were applied. Model‐agnostic analyses indicated there were effects of outcome history on reaction time and accuracy, and that the effects on accuracy related to catastrophizing. The overall model of best fit was the Standard Rescorla–Wagner Model and the best‐fitting model to include history was a model in which learning rate was scaled by history of negative outcome. We found no effect of catastrophizing on the scaling by history of negative outcome parameter (r = 0.003, p = 0.679), the learning rate parameter (r = 0.026, p = 0.703), or the inverse temperature parameter (r = 0.086, p = 0.220). We were unable to relate catastrophizing to any of the reinforcement learning parameters we investigated. This implies that catastrophizing is not straightforwardly linked to any changes to learning after a series of negative outcomes are received. Future research could incorporate further exploration of the space of models which include a history parameter.

Easy and green synthesis of TiO2 (Anatase and Rutile): Estimation of crystallite size using Scherrer equation, Williamson-Hall plot, Monshi-Scherrer Model, size-strain plot, Halder- Wagner Model

TiO2 is one of the most important metal oxides which are widely applied in various fields, and the modifications of synthesis process and in-depth characterization are growing up day by day. Nano Anatase and Rutile phases of TiO2 were synthesized from titanium iso-butoxide following an easy approach where no toxic chemicals were utilized. Nano-TiO2 (Rutile phase) was synthesized from the thermal conversion of the nano-Anatase phase (which was obtained at room temperature) at 700 °C temperature for 2 h. Anatase and Rutile phases were confirmed by the X-ray diffraction (XRD) data and matched with the standard database. Different crystallographic parameters such as lattice parameters, and preference growth were calculated from the XRD data. Different methods were utilized to estimate the crystallite size of the Anatase and Rutile phase of TiO2 by using the Scherrer equation, Williamson-Hall plot, Monshi-Scherrer Model, Size-strain plot method, Halder- Wagner Model, and Sahadat-Scherrer Model. All the models presented crystallite size in the accepted region, and linear regression coefficients were also taken into consideration. In addition to the crystallite size, various intrinsic parameters such as stress, strain and energy density were also computed from the mentioned models based on XRD.

Synthesis of M-type hexaferrite reinforced graphene oxide composites for electromagnetic interference shielding

This study focused on addressing the increasing demand for materials that can effectively shield against electromagnetic interference. In particular, Ba0.7Mn0.3Nd0.1Fe11.9O19 M-type hexaferrite was synthesized using the sol–gel auto-combustion method and sintered at 1050 °C. The modified Hummer process was used to prepare graphene oxide (GO), and three composites were then synthesized with the ultrasonication method, which were denoted as C-1 (90 % M-ferrite + 10 % GO), C-2 (80 % M-ferrite + 20 % GO), and C-3 (70 % M-ferrite + 30 % GO). X-ray diffraction (XRD) analysis confirmed the formation of the hexagonal phase of the M-type barium hexaferrite and GO. A prominent peak at an angle of 8.82° corresponding to the (001) reflection was observed by XRD analysis for the GO sample and it confirmed the effective oxidation of graphite and formation of GO. Scanning electron micrographs of M-type hexaferrite demonstrated the formation of platelet-like grains with hexagonal shapes, which were suitable for microwave absorption. The direct current electrical resistivity at room temperature was determined as 2.08 × 10−8 Ω-cm for the M-type ferrite, and the resistivity of the composites decreased as the concentration of GO increased due to the superior conductivity of GO compared with the ferrite. The dielectric properties of all samples followed the Maxwell–Wagner model. The dielectric characteristics increased in magnitude as the GO content increased. The AC magnetic susceptibility decreased for the M-type ferrite and three composites as the temperature increased to eventually reach a steady state at a specific temperature known as the Curie temperature. Except for GO, the Curie temperatures of all samples were within the range of 348 K–450 K. Coupling magnetic ferrite with GO allows the magneto-electrical characteristics to be tuned, with possible uses in electronic devices, electromagnetic shielding, supercapacitors, and water purification.

Plasticity-led evolution as an intrinsic property of developmental gene regulatory networks

The modern evolutionary synthesis seemingly fails to explain how a population can survive a large environmental change: the pre-existence of heritable variants adapted to the novel environment is too opportunistic, whereas the search for new adaptive mutations after the environmental change is so slow that the population may go extinct. Plasticity-led evolution, the initial environmental induction of a novel adaptive phenotype followed by genetic accommodation, has been proposed to solve this problem. However, the mechanism enabling plasticity-led evolution remains unclear. Here, we present computational models that exhibit behaviors compatible with plasticity-led evolution by extending the Wagner model of gene regulatory networks. The models show adaptive plastic response and the uncovering of cryptic mutations under large environmental changes, followed by genetic accommodation. Moreover, these behaviors are consistently observed over distinct novel environments. We further show that environmental cues, developmental processes, and hierarchical regulation cooperatively amplify the above behaviors and accelerate evolution. These observations suggest plasticity-led evolution is a universal property of complex developmental systems independent of particular mutations.

Impact of Process Parameters and Dopant Concentration on Structural, Magnetic, and Dielectric Properties of Dysprosium-doped Nickel-Zinc Ferrites Synthesized by Microwave Hydrothermal Method

This study aims to investigate the impact of substituting Dy3+ ions on the structural, magnetic and dielectric properties of Nickel Zinc (Ni-Zn) ferrites, which have the chemical formula Ni0.5Zn0.5DyxFe2-xO4 (where x = 0, 0.01, 0.03, 0.05, 0.07, and 0.09). These ferrites were synthesized using a microwave hydrothermal technique with different process parameters. Structural characterization of the synthesized powders was carried out using X-ray diffraction (XRD) and Fourier transformation infrared spectroscopy (FTIR). The XRD analysis confirmed the presence of a pure spinel phase for Dy concentrations (x) up to 0.05. However, when x ≥ 0.07, an additional orthoferrite phase (DyFeO3) was observed along with the spinel phase. FTIR spectra revealed a shift in low-frequency wave numbers due to Dy3+ ion substitution. The size and morphology of the synthesized powder particles were examined using field emission scanning electron microscopy (FESEM). The powder compacts were sintered using microwave processing at 900 °C for 40 min. The increase in dc. resistivity is observed with an increase in Dy3+ concentration, mainly due to the change in the hopping mechanism with the substitution concentration. Dielectric properties such as dielectric constant and loss are measured in the frequency range of 100 Hz to 1.8 GHz. The high value of dielectric constant and loss observed in the low-frequency region compared to the high-frequency region. Maxwell’s Wagner model and ‘Koop’s theory explains the variation in dielectric properties with the frequency. The magnetic hysteresis loops were measured at different temperatures and observed to enhance the low-temperature magnetic properties compared to room temperature. The results suggest that the magnetic and dielectric properties of the investigated samples can be adjusted by varying the concentration of Dy3+ ions, providing the ability to tailor these properties according to specific application requirements.

How associations become behavior

The Rescorla and Wagner (1972) model is the first mathematical theory to explain associative learning in the presence of multiple stimuli. Its main theoretical construct is that of associative strength, but this is connected to behavior only loosely. We propose a model in which behavior is described by a collection of Poisson processes, each with a rate proportional to an associative strength. The model predicts that the time between behaviors follows an exponential or hypoexponential distribution. This prediction is supported by two data sets on autoshaped and instrumental behavior in rats.

Ferroelectric, Magnetic and Dielectric Properties of SrCo0.2Zn0.2Fe11.6O18.8 Hexaferrite Obtained by “One-Pot” Green Sol-Gel Synthesis Utilizing Citrus reticulata Peel Extract

SrCo0.2Zn0.2Fe11.6O18.8 hexaferrite was obtained by a “one-pot” green sol-gel synthesis method utilizing aqueous mandarin orange (Citrus reticulata) peel extract as an eco-friendly reactant. The research objective was to analyze the influence of cobalt and zinc co-doping and the synthesis process on the structure, morphology, magnetic, dielectric and ferroelectric properties of strontium hexaferrite in view of future applications. Structural and morphological characterization using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy coupled to energy dispersive X-ray spectrometry (SEM-EDX) confirmed the formation of a Co and Zn ion incorporated M-type magnetoplumbite with c/a lattice parameter ratio of 3.919 as crystallite nanoplatelets of 32 and 53 nm in thickness and width, respectively. The magnetic hysteresis loop of the synthesized powder recorded by a vibrating sample magnetometer (VSM) at room temperature confirmed its ferromagnetic nature with a coercive field (Hc) of 2539 Oe and a saturation magnetization (Ms) and remanent magnetization (Mr) of 44.6 emu/g and 21.4 emu/g, respectively. Room temperature ferroelectric loops measured at 100 Hz showed a maximal (Pmax) and a remanent (Pr) polarization of 195.4 and 31.0 nC/cm2, respectively. Both increased when the magnitude of the applied electrical field increased in the 1–24 kV/cm range. The dielectric constant decreased with the frequency increase, in accordance with the Maxwell–Wagner model, while the conductivity changed according to the Jonscher power law. The complex impedance was modeled with an equivalent circuit, enabling identification of the dominant contribution of grain boundary resistance (272.3 MΩ) and capacitance (7.16 pF).

Improving the health outcomes of individuals with chronic illness through the delivery of healthcare services

The move in the healthcare system toward an emphasis on chronic care may be easier to manage if the Wagner model serves as a guide. We define the health demands of patients with chronic disease and compare them to services that should ideally be supplied by a patient-centered health system, drawing on components of this framework and health policies linked to patient-centered care. This article helps readers better understand the unique problems patients face using chronic circumstances with their family carer while interacting with the healthcare scheme and a service provider. To understand more about the challenge faced by the populace utilizing complex diabetes, Chronic Heart Failure (CHF), or chronic obstructive pulmonary disease (COPD), we conducted interviews with patients, carers, and healthcare professionals (HCPs). Patients indicated a variety of demands and objectives about the caliber of their interactions with HCPs, and these needs and wishes were conveyed as worries. There was a need for 1) better HCP communication and information delivery; 2) more organized health services with shorter stages to see HCPs; 3) support for self-care; 4) a better professional understanding of the requirements for holistic as well as ongoing care; and 5) patient as well as caregiver involvement in Decision-Making Processes (DMP). Health policy is more closely linked than it now is to accommodate the needs and preferences of persons with chronic conditions and solve their issues