Field Interaction Research Articles

Examination of Magnetic Field Signatures and Local Plasma Distribution Variations in Jupiter's Magnetosphere

AbstractSpinning disk of plasma results in deformation of Jupiter's magnetic field from a dipole to a magnetodisc configuration with significant radial and azimuthal components. Polar orbit of the Juno spacecraft enables a comprehensive in situ observation of Jupiter's plasmadisc at different latitudes. Observations from magnetometer and plasma distribution instruments on Juno mission were used to examine interaction of magnetic field and heavy ions in Jupiter's nightside magnetosphere. Power spectrum analysis was used to evaluate magnetic fluctuations inside and outside of the plasmadisc. Extensive radial maps of magnetic activity in Jupiter's nightside magnetosphere are presented. Comprehensive examination of magnetic fluctuations enable to identify local plasma density variations that correlate with plasma distribution count rate fluctuations. Observations of magnetic signatures together with examination of plasma distribution are used to detect features that point to plasma transport inside and outside of Jupiter's plasmadisc. This work shows that plasma in Jupiter's magnetosphere is contained near centrifugal equator and is not a subject to curvature drift that could generate ring currents. Signatures described as current sheet crossings were investigated. On close inspection these signatures show attributes that belong to stand alone formations rather than a single current sheet structure. This work shows that current flow is not an adequate mechanism to explain deformation of Jupiter's magnetic field.

Magnetic-induced chiral dynamics in an extended two-leg bosonic ladder

The realization and detection of chiral physics with ultracold atomic gases provide a unique path for the exploration of topological phases. Here, we show that the interplay of magnetic field and interacting particles in an extended two-leg ladder leads to rich chiral Bloch dynamics. Considering both the on-site contact interaction and nearest-neighbor interactions, the ground state and Bloch dynamics of the system are studied analytically and numerically. When the system is in the ground state, the threshold and phase diagram for the transition between zero-momentum state and plane-wave state are analytically obtained, showing the nearest-neighbor interactions along the legs and rungs have opposite impact on the ground state transition, providing new opportunity to manipulate the ground state transition. When the ladder is perturbated under an external linear force, chiral dephasing of Bloch oscillations (BOs), i.e. symmetry breaking damped BOs (the damping rate of BOs on one leg is larger than the other), are observed. This chirality is absent for vanishing the magnetic field and atomic interaction. Particularly, the chirality of damped BOs is inversed when the magnetic field (chiral current) is inversed. In addition, the damping of BOs induced by different types of atomic interactions is different, and the strength and damping rate of BOs initialized in different ground states are distinct, offering dynamic ways to detect the different ground states. Furthermore, the persistent chiral Bloch oscillations observed in single particle case is predicted analytically, which is a crucial requirement for observation and application of chiral BOs in nonlinear regime. Our results provide an interesting path towards the exploration of topological atomic superfluids.

THEORETICAL FOUNDATIONS OF SOCIAL INTERACTION DEVELOPMENT THROUGH SPORTS SOCIALIZATION

The article presents the theoretical foundations of researching the development of social interaction through sports socialization. Research methods such as systematization, generalization, and analysisof the main provisions of the «self-determination theory» and «flow theory» were used, including their comparison in the social and sports spheres. The main aspects of forming intrinsic motivation of individuals and its influence on societal well-being are discussed. Preconditions of «psychological immersion» are identified and described, wherein individuals become fully immersed in activities and derive maximum satisfaction from the process itself. The peculiarities of studying intersocial interaction that satisfy the basic psychological needs of individuals are highlighted. According to the research results, the application of the «self-determination theory» and «flow theory» can improve the psychological climate and development of social interaction in society and the sports industry. It is found that a significant outcome of applying these theories is the emergence of a «state of flow» in individuals, characterized by complete absorption in activities and a sense of complete social wellbeing. This can be achieved by providing individuals with a sense of control over their actions and supporting their achievements. Understanding the psychological mechanisms of developing intrinsic motivation and addressing the psychological needs of individuals can enhance the work of social services and effectively engage society in important sociocultural projects.The application of the «self-determination theory» and «flow theory», according to the authors, can positively influence the psychological climate and development of social interaction in various fields, including sports and social work. Further research on the «self-determination theory» and «flow theory» will help social workers better influence the formation of social skills in individuals in various spheres and their effective interaction in society.

Dynamical interactions of the magnetic field in a binary mixture of interacting thermoelastic solids

A more focused scientific approach in the context of a mixture of thermoelastic solids would entail investigating the basic ideas guiding the behavior of the complex materials, including constitutive model development, multi-scale modeling at various length scales, and design optimization for thermoelastic solids with their precise properties. The present work is set up to study the effect of the magnetic field as an external effect on the mixture of two interacting thermoelastic solids. The fundamental mathematical equations were shown and solved by the analytical harmonic wave solution to give the solution of the descriptive functions of the discussed problem. The displacements and stresses for the mixture of the two interreacted thermoelastic solids with the mutual temperature were clarified in the 2-D and 3-D. The results are analyzed and discussed. The obtained solution for the functions is finite everywhere. The solutions for the quantities of practical interest are represented graphically with different choices of the wave number of the harmonic wave as the magnetic field with time. In addition to the numerous physical factors in the governing field equations as depicted in the figures, boundary conditions also play a role in the current damping phenomenon.

Multi-scale simulation of typhoon wind field at building scale utilizing mesoscale model with nested large eddy simulation

Based on the mesoscale WRF (Weather Research Forecast) and LES (Large Eddy Simulation), an integrated numerical simulation framework aiming to resolve typhoon wind fields around urban building blocks has been developed. The holistic multi-scale simulation spans four scales: macroscale (∼1000 km), mesoscale (∼100 km), microscale (∼1 km), and building scale (0.1–100m). By interactively sharing the meteorological data among different scales, this simulation framework addressed the challenge of downscaling typhoon effects in urban environments. Typhoon weather reanalysis and urban wind field simulation were conducted by the WRF model with nested computational domains incorporating high-resolution topography data. For the downscaled LES model with urban buildings, the wind profiles produced by the WRF model were used at the interface with provided turbulent fluctuations in the flow. K11 building is a 270-m-tall building located in a densely built-up area of Hong Kong. Wind velocity and pressure fields surrounding the K11 building in Hong Kong during Typhoon Kammuri were obtained by the proposed framework, and the simulation results were validated by comparing with the meteorological data and full-scale measurements at the top of the K11 building. The interactions of the wind fields and building clusters resulting in vortex shedding, separation, and channeling effects have been resolved at high resolutions. Probabilistic distributions and higher-order statistics of wind pressure, i.e., skewness and kurtosis, were presented to highlight non-Gaussian characteristics of the simulated local wind pressure on the K11 building. Based on the simulated wind pressure, wind-induced vibration of the K11 building during the typhoon was analyzed and compared to the measurements.

Magnetic field impact on ferronanofluid laminar flow

A comprehensive understanding of the magnetic field interaction with the flow of ferronanofluids is essential to determine the heat transfer effect and the potential for use in industrial applications. The purpose of this work is to determine the effects of magnetic field orientation and intensity, as well as inertia forces, on heat transfer in the laminar flow of a ferronanofluid. The experiment involved the use of five permanent magnets positioned both below and above the flowing magnetite-based ferronanofluid. The analysis of the effect on heat transfer is carried out using the similarity numbers, Reynolds number (ratio of inertia and viscous forces), magnetic number (ratio of magnetic and inertia forces) and product of the two (ratio of magnetic and viscous forces).The findings indicate that the orientation of the magnetic field relative to temperature gradient-induced secondary motions plays a crucial role in either enhancing or inhibiting heat transfer. The magnet positioned below the flow leads to improved heat transfer, while placement above hinders it. To determine the magnetic field effect on heat transfer, the ratio of magnetic to viscous force introduced as MnRe is used. Taking the 5 % Nusselt number change as the threshold, the critical value for the orientation of magnet above the tube is MnRe = 24,000, while for the configuration with the magnet below, MnRe = 32,000 for Re = 109 and MnRe = 88,000 for Re = 150 and 163. The magnetic field effect is local and diminishes as the fluid flows, ultimately causing the heat transfer parameters to revert to their reference state. However, an increase in the ratio of inertia and viscosity forces enables the magnetic field interaction effect to propagate over a longer distance.

Effect of the magnetic field on the conductance and spin polarization in phosphorene superlattice

The spin-dependent conductance and spin polarization are investigated theoretically in a phosphorene superlattice in the presence of external magnetic field and Rashba interaction. It is demonstrate that, the spin-dependent conductance with and without spin-flip as well as spin polarization can be effectively controlled by changing the magnetic field strength and the number of the superlattice barriers. For small magnetic field strength, the conductance for with and without spin-flip shows an oscillating behavior as increasing the strength of the Rashba interaction, and by increasing the number of barriers, the oscillating behavior becomes prominent. Further, when the magnetic field is greater than a limit value, the spin conductance will be zero. The size of the spin-dependent transmission window in the phosphorene superlattice under external magnetic field decreases drastically. The magnitude, sign and behavior of the spin polarization can be tuned by the amount of the external magnetic field.

Emerging Technologies and Evolving Work Practices Impacting Employee Engagement: Automobile industry

Purpose: The manufacturing industry has been at the cutting-edge of technology advancements, which has improved quality and profoundly altered work practises. Technology disruptions are redefining work practices, resulting in innovation and creativity driving higher productivity and performance. Man-machine collaboration is profoundly strengthening manufacturing, increasing product quality and safety features. Robots, Cobots working alongside the shopfloor act as a substitute human workforce, increasing productivity and performance Theoretical framework: Multiple theories support employee turnover studies and the job embeddedness theory suits this study the most. JE theory clearly states that employees who feel connected to the social and professional phase within the organization are less likely to leave. Likewise, motivated and up skilled employees will tend to have better QOL and QWL. Design/methodology/approach: The study was conducted over three months in the automobile industry, and the design adopted a mixed method approach; primary evidence was collected from the field as an interview method, and also various scholarly evidence collaborated with our study. The research design is descriptive and deductive in nature. The methodology used in the research paved the way to answer the critical research question with the help of a theory. Findings: Adapting to new work practices results in changes to job design as employers optimize their workforces to meet the demands of the latest techniques. Implementing disruptive technologies can improve the efficiency, safety, and fulfilment of the workplace in the automobile industry. The new-age practices driven by disruptive technologies enhance skill development, productivity, and employee engagement Research, practical & social implications: Disruptive technologies are improving the safety and quality parameters. Organizations focusing on employees' up skilling based on learning preferences and learning styles tremendously impact productivity, motivation, and morale, enhancing job satisfaction and employee retention. Originality/value: Data collected from the field interactions derived the factual position which was tested using various statistical tool to ensure reliability and validity. Findings added to the body of knowledge further.

Drafting behaviors in fish induced by a local pressure drop around a hydrofoil model

Fish schooling has the improvement in hydrodynamic propulsive efficiency through the interaction of flow field induced by fish bodies and tail beat. Such energy-saving behaviors due to flow interactions also occur with changes in the flow field caused by structures. We examined the differences between a live fish swimming around a streamlined hydrofoil model prepared to represent fish body and swimming alone in a flow tank. We observed that the fish can remain in the same place without tail beating. It called “drafting” behavior. The analysis of fish drafting showed that fish obtained thrust using a local pressure drop caused by the high velocity flow even in the vicinity of the hydrofoil model at an angle of attack α of 10° to 20°without flow separation, and fish balanced forces by using an α of fish body. This tendency was confirmed in the model experiment using a two-axis load cell, and the forces acting on the fish body was the smallest value when the fish model was placed in the same conditions as a live fish experiment. We also confirmed by simulation and found that the α of fish body generated lift force and counteract the suction force. Above results indicate that a fish can balance the anterior–posterior and lateral direction forces by using a local pressure drop around a hydrofoil model as suction force, and using angle of attack on its body, thereby realizing drafting.

Engineering Clock Transitions in Molecular Lanthanide Complexes.

Molecular lanthanide (Ln) complexes are promising candidates for the development of next-generation quantum technologies. High-symmetry structures incorporating integer spin Ln ions can give rise to well-isolated crystal field quasi-doublet ground states, i.e., quantum two-level systems that may serve as the basis for magnetic qubits. Recent work has shown that symmetry lowering of the coordination environment around the Ln ion can produce an avoided crossing or clock transition within the ground doublet, leading to significantly enhanced coherence. Here, we employ single-crystal high-frequency electron paramagnetic resonance spectroscopy and high-level ab initio calculations to carry out a detailed investigation of the nine-coordinate complexes, [HoIIIL1L2], where L1 = 1,4,7,10-tetrakis(2-pyridylmethyl)-1,4,7,10-tetraaza-cyclododecane and L2 = F- (1) or [MeCN]0 (2). The pseudo-4-fold symmetry imposed by the neutral organic ligand scaffold (L1) and the apical anionic fluoride ion generates a strong axial anisotropy with an mJ = ±8 ground-state quasi-doublet in 1, where mJ denotes the projection of the J = 8 spin-orbital moment onto the ∼C4 axis. Meanwhile, off-diagonal crystal field interactions give rise to a giant 116.4 ± 1.0 GHz clock transition within this doublet. We then demonstrate targeted crystal field engineering of the clock transition by replacing F- with neutral MeCN (2), resulting in an increase in the clock transition frequency by a factor of 2.2. The experimental results are in broad agreement with quantum chemical calculations. This tunability is highly desirable because decoherence caused by second-order sensitivity to magnetic noise scales inversely with the clock transition frequency.

Theoretical investigation of the giant magnetocaloric effect in Er0.7Tm0.3Al2

This study presents a theoretical investigation of the giant magnetocaloric effect recently reported in the intermetallic compound Er0.7Tm0.3Al2. Our model Hamiltonian includes the crystalline electrical field, exchange, and Zeeman interactions in both Er3+ and Tm3+ sublattices. A remarkable agreement was achieved between the theoretical calculations and experimental data concerning heat capacity, ΔST and ΔTad (magnetocaloric quantities). Additionally, the analysis of magnetic anisotropy and simulations for the rotating magnetocaloric effect in Er0. 7Tm0.3Al2 were performed. The maximum value for the rotating magnetocaloric effect was predicted around the temperature of spin reorientation transition from the <111>-easy to the <001>-hard magnetization directions.

Energy Harvester Based on a Rotational Pendulum Supported with FEM

The proposed energy harvesting system is based on a rotational pendulum-like electromagnetic device. Pendulum energy harvesting systems can be used to generate power for wearable devices such as smart watches and fitness trackers, by harnessing the energy from the human body motion. These systems can also be used to power low-energy-consuming sensors and monitoring devices in industrial settings where consistent ambient vibrations are present, enabling continuous operation without any need for frequent battery replacements. The pendulum-based energy harvester presented in this work was equipped with additional adjustable permanent magnets placed inside the induction coils, governing the movement of the pendulum. This research pioneers a novel electromagnetic energy harvester design that offers customizable potential configurations. Such a design was realized using the 3D printing method for enhanced precision, and analyzed using the finite element method (FEM). The reduced dynamic model was derived for a real-size device and FEM-based simulations were carried out to estimate the distribution and interaction of the magnetic field. Dynamic simulations were performed for the selected magnet configurations of the system. Power output analyses are presented for systems with and without the additional magnets inside the coils. The primary outcome of this research demonstrates the importance of optimization of geometric configuration. Such an optimization was exercised here by strategically choosing the size and positioning of the magnets, which significantly enhanced energy harvesting performance by facilitating easier passage of the pendulum through magnetic barriers.

Functional Formulation of Quantum Theory of a Scalar Field in a Metric with Lorentzian and Euclidean Signatures.

We study the Schrödinger equation in quantum field theory (QFT) in its functional formulation. In this approach, quantum correlation functions can be expressed as classical expectation values over (complex) stochastic processes. We obtain a stochastic representation of the Schrödinger time evolution on Wentzel-Kramers-Brillouin (WKB) states by means of the Wiener integral. We discuss QFT in a flat expanding metric and in de Sitter space-time. We calculate the evolution kernel in an expanding flat metric in the real-time formulation. We discuss a field interaction in pseudoRiemannian and Riemannian metrics showing that an inversion of the signature leads to some substantial simplifications of the singularity problems in QFT.

Microwave assisted Fraunhofer diffraction pattern in a four-level light–matter coupling scheme

The experimental realization of two-dimensional (2D) electromagnetically induced grating is explored by monitoring the Fraunhofer diffraction pattern in a microwave-driven four-level Y-type atomic medium under the action of two orthogonal standing-wave (SW) fields. Due to the position-dependent atom–field interaction, the information about the high diffraction order of the probe light can be obtained via the Fraunhofer diffraction pattern of the probe light. It is found that the diffraction behavior is significantly improved due to the joint quantum interference induced by the SW and microwave-driven cycling fields. Most importantly, the amplitude and phase diagram of the transmission function of the probe light can be modulated at a particular position and the probe energy may transfer to the high orders of the diffraction by properly adjusting the system parameters. The proposed scheme may provide a promising way to achieve highly sensitive diffraction patterns with applications in quantum information processing.

Off-shell fields and conserved currents

We study interactions of higher-spin massless fields φ with conserved currents multilinear in the off-shell matter fields ϕ. Specifically, we focus on the 3d case where a slight modification of the σ−-cohomology technique developed earlier is directly applicable to control nontriviality of the interaction vertices at the convention that the vertices removable by a local field redefinition of a higher-spin field or having schematic form F(φ)G(ϕ), where F(φ) is a gauge invariant field strength of a free higher-spin field, are called deformationally trivial. It is demonstrated how the σ−-cohomology approach can be applied to the analysis of nonlinear vertices. Generally, deformationally trivial vertices are not σ−-closed while the deformationally non-trivial ones must be in H(σ−). It is shown that, at least in the 3d case, the relevant cohomology group H1(σ−)=0 and, hence, no deformationally non-trivial off-shell vertices exist. On the other hand, there exists an infinite class of deformationally trivial vertices, that includes the vertex recently proposed for spin three. Our analysis goes beyond the higher-spin vertices allowing to show that, at least in three dimensions, nonlinear combinations of the off-shell scalar fields and their derivatives cannot obey non-trivial equations.

First study of quantitative relationship between electric polarization and electromagnetic interference (EMI) shielding effectiveness of CFRP

This study investigates the electric polarization, including direct current (DC) and alternating current (AC), and electromagnetic interference (EMI) shielding capabilities within the microwave range (2.5–3.9 GHz) of cross-ply continuous carbon fiber-reinforced polymer (CFRP) composites, constructed by stacking prepreg composites. The DC conductivity of CFRP was evaluated using a multimeter, while the AC relative permittivity was measured with electronic test equipment (LCR meter). To describe the relationship between shielding effectiveness and polarization behavior, the EMI shielding of CFRP was assessed using the waveguide method, presenting a quantitative description of this relationship for the first time. Results indicate a decrease in DC conductivity with increasing specimen thickness due to increasing defects. Conversely, AC permittivity increases with specimen thickness, attributed to a rise in charged carriers and associated carrier-atom interactions. Skin depth δ, at a given thickness, follows a trend of initial decrease and subsequent increase with rising frequency; at a given frequency, it increases with decreasing specimen thickness. The interaction between CFRP and radiation is primarily reflective, with the reflection coefficient being much higher than the absorption coefficient across the frequency range, escalating with specimen thickness. Shielding effectiveness (SET) and absorption loss (SEA) display an initial increase followed by a decrease with rising frequency, whereas reflection loss (SER) sees a slight increase. For the smallest thickness, SEA per unit thickness exceeds 3120 dB/m and 7960 dB/m using specimen and carbon thickness, respectively. The absorption loss predominantly arises from the interaction of the electric field with electric dipoles formed by carrier-atom interaction at defects.

Analysis of PPL Implementation in The Prajabatan PPG Program In The Field of Sociology Studies At SMA Negeri 1 Pontianak

This research aims to identify the effectiveness of implementing Field Experience Practices (PPL) in developing the competency of Pre-Service Teacher Professional Education Program (PPG) students at SMA Negeri 1 Pontianak. The relevance of this research lies in its contribution to improving the quality of learning in schools and preparing Pre-Service PPG students to become competent teachers and ready to face the dynamics of the world of education. This research method uses a descriptive qualitative approach through data collection techniques through observation, interviews, and document analysis. The research population was PPL PPG students in the field of Sociology studies at SMA Negeri 1 Pontianak, the research informants were 3 students. Effective PPL allows students to develop analytical, reflective skills and teacher identity through field interaction, observation and reflection. Even though they face obstacles such as limited schedules, effective communication between students and the school can overcome them. PPL plays an important role in forming competent and professional teachers in the future. Thus, this research provides recommendations for increasing the effectiveness of PPL implementation, including by optimizing communication between students and school officials, arranging flexible schedules, and increasing the availability of facilities at schools. By overcoming these obstacles, it is hoped that the implementation of PPL can run more effectively and efficiently so that students can develop competence as prospective teachers who are ready to face the dynamics of the world of education.

Effective graviton mass in de Sitter space

We calculate the effective mass of gravitational perturbations induced by the interaction of the classical gravitational field with quantum matter in the background of the Poincaré patch of de Sitter space. Using the Schwinger-Keldysh diagrammatic technique, the one-loop effective action is calculated, and it is shown that the graviton does not acquire mass for the most symmetric Bunch-Davies state. However, we have shown that even in this case, there is a nontrivial modification of the theory at one loop in the scalar sector of gravity. Published by the American Physical Society 2024

Baroclinic Sea Level

AbstractSea level and its horizontal gradient are an expression of oceanic volume, heat content, and currents. Large‐scale currents have historically been viewed as mostly “baroclinic,” and tides as “barotropic,” respectively, in the loose sense of being strongly related to the oceanic density distribution or not. In particular, the evolution of the barotropic velocity is influenced by a horizontal pressure‐gradient force that depends on the gradient of a particular depth‐weighting of the density field as well as on the gradient of the sea‐surface elevation ζ; hence, even the tides must be viewed as a product of the coupled interaction of barotropic and baroclinic fields. The purpose of this note is to give dynamical precision to the distinction between barotropic and baroclinic contributions to ζ and the surface pressure‐gradient force −g∇ζ, and, in the particular case of the tides, demonstrate their combined barotropic‐baroclinic interactions with a realistically forced, high‐resolution simulation of the Pacific Ocean circulation. While the different tidal sea‐level contributions manifest a horizontal scale separation (e.g., more barotropic at larger scales; more baroclinic surface pressure‐gradient force at smaller scales), there are cross‐mode corrections in both at the level of tens of percent. The proposed barotropic‐baroclinic decomposition is generally relevant to the sea‐level expression of oceanic currents.

Nonisospectral water wave field: Fast and adaptive modal identification and prediction via reduced-order nonlinear solutions.

Real-world water wave fields exhibit significant nonlinear and nonisospectral characteristics, making it challenging to predict their evolution by relying solely on numerical simulation or exact solutions using integrable system theory. Hence, this paper introduces a fast and adaptive method of modal identification and prediction in nonisospectral water wave fields using the reduced-order nonlinear solution (RONS) scheme. Specifically, we discuss the coarse graining and mode extraction of wave field snapshots from the data-driven and physics-driven perspectives and utilize the RONS method for principle modal prediction of nonisospectral water wave fields. This is achieved by investigating the standard and nonisospectral Gardner system describing nonlinear water waves as a demonstration. Through detailed comparison and analysis, the fundamental solitary behaviors and dispersive effects in the Gardner system are discussed. Subsequently, a neighbor approximation is developed that combines the essences of symbolic precomputation and numerical computation in the RONS procedure, which exploits the locality of nonlinear interactions in water wave fields.