Synchronous Mode Research Articles

A Novel Hydraulic Interconnection Design and Sliding Mode Synchronization Control of Leveling System for Crawler Work Machine

To address the issues of easy overturning and poor safety of crawler work machines operating on steep slopes in hilly and mountainous areas, this study develops a structural design scheme based on a “three-layer frame” structure. An omnidirectional leveling system with hydraulic interconnection is designed to maintain platform stability by ensuring a stationary central point during leveling. Furthermore, a sliding mode synchronization control method based on a disturbance observer is proposed to reduce the synchronization error of the hydraulic cylinders and enhance leveling precision. The system’s performance is validated through an AMESim-MATLAB/Simulink co-simulation platform, demonstrating significant improvements over traditional PID control. Specifically, both lateral and longitudinal leveling times are reduced, rise time decreases by 21.8% on average, and overall leveling time is reduced by 35.5%, with synchronization errors maintained within ±6 × 10−4 m. Finally, physical prototype testing further confirms the system’s effectiveness, achieving an average body inclination error of 2.55% and a hydraulic cylinder synchronization error of 8.2%. These findings validate the feasibility and superiority of the proposed omnidirectional leveling system for the crawler work machine in hilly and mountainous regions.

Frustrated Synchronization of the Kuramoto Model on Complex Networks.

We present a synchronization transition study of the locally coupled Kuramoto model on extremely large graphs. We compare regular 405 and 1004 lattice results with those of 12,0002 lattice substrates with power-law decaying long links (ll). The latter heterogeneous network exhibits ds>4 spectral dimensions. We show strong corrections to scaling and mean-field type of criticality at d=5, with logarithmic corrections at d=4 Euclidean dimensions. Contrarily, the ll model exhibits a non-mean-field smeared transition, with oscillating corrections at similarly high spectral dimensions. This suggests that the network heterogeneity is relevant, causing frustrated synchronization akin to Griffiths effects.

Aligning Peer Tutoring System in Language Education: A Comparative Study of Face-to-face and Online Delivery Modes

This paper not only addresses the academic gap in current pedagogical practices but also connects with broader educational goals of equipping learners with skills that are directly applicable in real-life situations, including the workplace. This paper sets out to present an action research study and discusses the design and implementation of a peer tutoring system for Cantonese as a second language learners at a university in Hong Kong. Background and theoretical considerations of this peer tutoring system are discussed. The special focus of this action research will be on the implementation of this peer tutoring system before and during the COVID pandemic and its sustainable development. This paper also discusses the change from face-to-face peer tutoring activities to synchronous interactive online mode during the pandemic, the re-conceptualization of pedagogical design, and the development of the peer tutoring system in the post-pandemic period. This paper addresses research questions relating to how effective the peer tutoring system is in facilitating students’ Cantonese learning and what advantages the peer tutoring system can bring to face-to-face and online delivery modes. The discussions are based on the analysis of feedback from tutors and tutees. Additionally, the possibility of applying blended and online peer tutoring in language education in the long run will also be discussed.

Synchronous firing transition between different regions of brain neural networks enhanced by Hamiltonian energy

Synchronous firing transition between different regions of brain neural networks enhanced by Hamiltonian energy

Synchronization transitions in adaptive simplicial complexes with cooperative and competitive dynamics.

Adaptive network is a powerful presentation to describe different real-world phenomena. However, current models often neglect higher-order interactions (beyond pairwise interactions) and diverse adaptation types (cooperative and competitive) commonly observed in systems such as the human brain and social networks. This work addresses this gap by incorporating these factors into a model that explores their impact on collective properties such as synchronization. Through simplified network representations, we investigate how the simultaneous presence of cooperative and competitive adaptations influences phase transitions. Our findings reveal a transition from first-order to second-order synchronization as the strength of higher-order interactions increases under competitive adaptation. We also demonstrate the possibility of synchronization even without pairwise interactions, provided there is strong enough higher-order coupling. When only competitive adaptations are present, the system exhibits second-order-like phase transitions and clustering. Conversely, with a combination of cooperative and competitive adaptations, the system undergoes a first-order-like phase transition, characterized by a sharp transition to the synchronized state without reverting to an incoherent state during backward transitions. The specific nature of these second-order-like transitions varies depending on the coupling strengths and mean degrees. With our model, we can control not only when the system synchronizes but also the way the system goes to synchronization.

Transition of synchronization state during the quasiperiodic route to chaos in coupled friction-induced continuous oscillators

Friction-induced vibration, particularly associated with the squealing problem in disk brake systems, has been a longstanding challenge in the automotive industry. In our research, we employed the synchronization theory to gain insights into the interaction between two coupled cantilever beams attached with tip masses. This proposed model emulates the dynamics of a mountain bike disk brake assembly. The work explores a range of collective behaviors, including synchronized periodic, multi-periodic, quasiperiodic, as well as desynchronized chaotic and quasiperiodic oscillations. Despite numerous studies reported on the synchronization phenomenon in discrete friction-induced oscillatory systems, there appears to be a lack of similar research on continuous systems. This work stands as the first of its kind in exploring the dynamics of synchronization between two coupled continuous systems exhibiting a quasiperiodic route to chaos. A bifurcation study is conducted utilizing the Poincaré points corresponding to the local maxima of oscillation amplitude with respect to the zero-velocity crossing. The results showed the existence of narrow multi-periodic windows during the quasiperiodic route at several locations. Additionally, the existence of multiple quasiperiodic attractors exhibiting different states of synchronization for the same set of parameters is observed. We analyzed the time evolution of the cumulative instantaneous phase difference between the coupled signals and identified distinct states of synchronization possessed by the system. The coupled system undergoes interesting phenomena such as complete phase lock, intermittent phase lock, and phase drifting. Moreover, the transition occurring to the state of synchronization during the quasiperiodic route to chaos is studied employing the phase locking value, the Pearson linear correlation coefficient, and the relative mean frequency. Notably, our findings revealed that while the Pearson correlation can effectively identify both the mode and strength of synchronization, other measures such as phase lock value and relative mean frequency only reflect synchronization strength.

Advanced Hierarchical Lithiophilic Scaffold Design to Facilitate Synchronous Deposition for Dendrite‐Free Lithium Metal Batteries

AbstractLocalized deposition behavior tends to induce the growth of lithium dendrite and hinder the the full utilization of lithium storage space, significantly impeding the practical application of 3D conductive hosts. Here, a novel synchronous deposition mode is proposed for the first time through hierarchical structure design of 3D Li host. The top‐down gradually enhanced lithiophilicity and conductivity of 3D scaffold provide sufficient driving force for Li+ to migrate downward, promoting synchronous Li deposition within the entire space of the host. Notably, the novel deposition mode has been theoretically and experimentally validated through finite element simulation and in situ optical microscopy, respectively. The meticulously designed strategy not only maximizes the utilization of the entire 3D scaffold space but also prevents the formation of Li dendrites under high current rate. Consequently, the symmetric Li//Li cell exhibits a long‐term cycling lifespan over 3700 h with a low overpotential of 15.6 mV, together with a Coulombic efficiency as high as 99.5% over 300 cycles at 3 mA cm−2. The full cell paired with LiFePO4 cathode demonstrates a cycling lifespan of 1000 cycles with a capacity retention rate of 91.6%. The proposed synchronous deposition strategy opens up a new paradigm for the design and construction of 3D hosts for dendrite‐free Li metal anode.

ADAPTATION OF EDUCATIONAL PROCESS PARTICIPANTS TO DISTANCE EDUCATION DURING THE PERIOD OF MARTIAL STATUS

Problem statement. The forced change in the form of education in higher education, which was first caused by the COVID-19 pandemic, and then by the introduction of martial law, requires all participants in the educational process to respond effectively to the emergence of new challenges. The process of adaptation to the forced transformation of the form of education is complex, both from the point of view of the technical possibilities of ensuring the quality of education, and from the point of view of the psycho-emotional state of students and teachers. It is impossible to create a comfortable educational environment without monitoring the needs of students. These needs are dynamic due to constant changes in the forms of education. Adaptation of students to new forms of education (without loss of quality) will depend on understanding their attitude to innovations in the organization of education and taking into account their opinion when planning further changes. Purpose of the article. Determining the attitude of students to the organization of education in a higher educational institution in the conditions of martial law, taking into account psychological aspects. Conclusion. The results of an online survey among students of higher education indicate the gradual adaptation of all participants in the educational process to various forms of education. In general, students are satisfied with conducting online classes according to the schedule (synchronous mode using the Zoom platform). From a psychological point of view, there are problems with concentration of attention when studying, associated with threats to health and life. The results of the survey indicate that more attention should be paid to psychological support. This can be done by offering students to study a separate elective discipline, which is aimed at obtaining skills to ensure personal protection during armed and/or informational aggression, or add to the list of mandatory topics for curatorial hours. In general, students positively evaluate the changes in the distance learning method that took place after its introduction since the beginning of the coronavirus pandemic. The majority of students are satisfied with the organization and conduct of education in a distance format. After the abolition of martial law in the country, the majority of master's students would choose distance learning, most bachelor's − mixed.

Mutual Synchronization of Spintronic Nano-Oscillator Ensembles

Introduction. The use of spintronic components significantly enhances the performance, reduces the size, and lowers the power consumption of modern electronic devices. The spintronic oscillator (SO) is an integral part of spintronic devices. Connecting several SOs (> 100) into ensembles with subsequent synchronization mitigates such SO drawbacks as low output power and high phase noise. These drawbacks appear as a result of an increase in the output power of an SO ensemble compared to a single oscillator under a simultaneous decrease in the spectral linewidth of the ensemble.Aim. To investigate the impact of connection topologies, synchronization mechanisms, and oscillator failures on the synchronization of oscillator ensembles.Materials and methods. The Kuramoto phase model was used to simplify the numerical modeling of synchronization of SOs connected into an ensemble.Results. A Kuramoto equation for phases of SOs connected in an ensemble was derived, and the influence of connection topologies and oscillator failures on the synchronization parameters of an ensemble of N connected oscillators was demonstrated.Conclusion. In order to ensure the shortest transition time of an SO ensemble to the synchronous mode, topologies with a higher number of connections between oscillators (e.g., "all-to-all") are preferable. The results obtained confirm the advantages of local connection of an SO ensemble by a common current, thus forming an "all-to-all" topology. This makes the transition time of the SO ensemble to the synchronous mode less dependent on both oscillator failures and the number of synchronized SOs.

First principle calculations of Janus 2D-TiSSe as an anodic electrode in batteries of lithium, sodium, and magnesium ions.

In recent years, rechargeable batteries have received considerable attention as a way to improve energy storage efficiency. Anodic (negative) electrodes based on Janus two-dimensional (2D) monolayers are among the most promising candidates. In this effort, the adsorption and diffusion of these Li, Na, and Mg ions on and through Janus 2D-TiSSe as anodic material was investigated by means of periodic DFT-D3 calculations. Electrochemical parameters were computed and compared. The diffusion barrier energies for migration of ions in monolayer TiSSe in three different potential directions were determined. Furthermore, the electronic properties and Mulliken charge analysis and plots of CDD were employed to investigate the interaction between ions and their surrounding surface. Our results show that the adsorption ability of TiSSe surface up to 32 metal ions falls in the following order: Li+ > Na+ > Mg2+. The maximum storage capacity is 337.37 mAh/g for Li/Na ion and 674.75 mAh/g for Mg ion. The average open-circuit voltage is 1.39, 0.93, and 0.73V for Li, Na, and Mg ions, respectively. Lastly, the minimum diffusion barriers follow the order Li+ < Na+ < Mg2+. The structural, energetic, and thermal stability of clean Janus surface and its saturated adsorbed systems was proved by MD simulations. In addition, we compared the obtained electrochemical parameters to those reported by other researchers. This comprehensive approach demonstrates valuable insights, furthering our understanding of TiSSe's behavior and its suitability for use in MIBs. DFT calculations were applied with projector augmented plane waves (PAWs)/PBE functional. A two-dimensional (2D) monolayer TiSSe surface was built with a 4 × 4 supercell. The energy cutoff of plane waves was set to 400eV. The DFT-D3 model has been used to incorporate van der Waals interactions. A geometric relaxation process was conducted using Monhkorst-Pack 8 × 8 × 1 in reciprocal space. The relaxation and electronic calculations were carried out using the Vienna Ab initio Simulation Package (VASP). Using the transition state (TS) search algorithm implemented in the Dmol3 module, linear synchronous transition and quadratic synchronous transit tools were utilized to find the minimum energy paths.

Improving Data Transfer Performance to Unlock Potential of Cloud Service Providers

Efficient data transfer among CSPs is essential for the performance of cloud computing's basic operations, such as migration and disaster recovery. In this research, a novel approach to enhance data transmission performance using DTNs is presented. Using DTNs wisely, the proposed method enhances the speed and reliability of sending huge volumes of data across several CSPs. Coordinating local and remote copy operations is also a part of the process as well as a mechanism for DTN-to-DTN transfers. Optimized network settings with NFS connections maximized data transfer speed. In order to optimize the network, we carried out a battery of experiments to determine the best setting by varying network buffer size, synchronous and asynchronous modes, among others. With asynchronous modes and the best possible NFS settings, results showed a dramatic improvement in data transmission speed. The method is scalable and reliable when looking to address the challenge of inter-cloud improvements with regard to data transfer within a multi-cloud environment.

Digital twin-based cross-enterprise production-delivery synchronization in a highly dynamic environment

Efficient collaboration between production and logistics is crucial for timely order fulfillment and stable operations of system, necessitating closer cooperation between manufacturers and third-party logistics providers. However, achieving cross-enterprise synchronization presents three main challenges. First, concerns regarding information privacy and security lead to disjointed and non-shared resources. Second, the decision-making is not coordinated and consistent in dealing with dynamic interference. Third, differentiated strategies emerge as manufacturers and 3PLs employ different batch processing methods for customer orders in pursuit of economies of scale. This multifaceted disconnect leads to significant asynchronization in cross-enterprise production-logistics, resulting in inefficiencies and increased costs throughout the system. To address these challenges, this paper focuses on three key aspects: a digital twin-based cross-enterprise information-sharing framework, a cross-enterprise synchronized mechanism, and a collaborative optimization based distributed decision method. These aspects provide an intelligent production-logistics synchronization solution in the unique environment of Industry 4.0. Finally, through a case study of a paint enterprise, this paper comprehensively evaluates the differences in performance of the Production-Logistics Synchronization System (PLSS) under various synchronization modes. The results indicate that the proposed solution enhances the collaborative efficiency of production-logistics while ensuring the information security of the collaborating parties, effectively reducing production and delivery costs.

QUAN ĐIỄM CỦA GIẢNG VIÊN VỀ VIỆC THỰC HIỆN CHƯƠNG TRÌNH TIẾNG ANH TRỰC TUYẾN ĐỒNG BỘ TẠI TRƯỜNG ĐẠI HỌC MỞ TP. HỔ CHÍ MINH

This study investigates lecturers' opinions on the non-major English program level A, which is currently being implemented in a synchronous online mode at Ho Chi Minh City Open University. A survey was conducted with the participation of lecturers who teach online for the program. Quantitative data were collected through questionnaires with the participation of all 23 lecturers, and qualitative data were obtained through interviews with 10 lecturers. The findings show that the lecturers believe that the program has prepared students quite well for the course and that both lecturers and students have the capacity and conditions to participate in this type of program. However, they still face various difficulties when teaching Speaking and Pronunciation skills as well as classroom management. These difficulties are due to the nature of synchronous online teaching, poor internet connection from students, technical issues, and most notably, some students’ attitudes that are not suitable for online learning. The lecturers also contributed some opinions on the regulations of the university on students’ behavior and exams for non-major English classes in synchronous online mode. Based on the above results, we propose some solutions to improve the effectiveness of the program.

Minimum-dissipation principle for synchronized stochastic oscillators far from equilibrium.

We prove a linear stability-dissipation relation (SDR) for q-state Potts models driven far from equilibrium by a nonconservative force. At a critical coupling strength, these models exhibit a synchronization transition from a decoherent into a synchronized state. In the vicinity of this transition, the SDR connects the entropy production rate per oscillator to the phase-space contraction rate, a measure of stability, in a simple way. For large but finite systems, we argue that the SDR implies a minimum-dissipation principle for driven Potts models as the dynamics selects stable nonequilibrium states with least dissipation. This principle holds arbitrarily far from equilibrium, for any stochastic dynamics, and for all q.

The impact of the virtual classroom on the development of oral communicative competence in qualifying secondary school learners: A case study of the provincial direction of national education in Agadir

The period, mandated by health decision-makers in Morocco, was characterised by a certain improvisation in terms of the approaches used to enssure some form of pedagogical continuity. WhatsApp groups emerged as one of the methods adopted in an imposed manner by most teachers who were content with the digital tools available. In this context, our article aims to analyze the technical, didactic and pedagogical functioning of distance sessions programmed in synchronous mode, in order to determine whether virtual classes simulated real ones. It also seeks to study their effect on the development of oral communicative competence in Moroccan high school students. For this, we employed a mixed methodology: online questionnaire and semi-directive online interview process. The results indicated that no oral production was carried out, and hence there is a barrier to achieve an effective level of communicative competence during virtual sessions.

Effects of Process Parameters on Microstructure Evolution of Pure Aluminum Target under Clock 135° Collaborative Hot Rolling: A Simulation Study

Based on the results of current research and experiments, clock 135° hot rolling has been widely considered to be the preferred method in target rolling. However, it has been found that the process parameters are of vital importance during the rolling. Therefore, this work focuses mainly on the investigation of the effects of the roll speed ratio and offset distance on the microstructure evolution of a pure aluminum (Al) target under clock 135° collaborative hot rolling. Taking the ultra-thick pure Al metal circular billet as a research object, firstly, the evolutionary behavior of the effective strain (ES) and grain refinement for a rolled piece under the clock counterclockwise 135° synchronous and asynchronous (the speed ratios between rollers are set to be 1:1.05, 1:1.1, 1:1.2, respectively) rolling modes has been comparatively studied based on numerical simulation by DEFORM-3D software. It has been shown that a large ES value of 5.835 mm/mm is obtained in the lower surface layer by counterclockwise 135° asynchronous rolling with a roll–speed ratio of 1:1.2. Meanwhile, the average grain size below 80 µm accounts for ~61.8% of the total grains. These results demonstrate that the clock counterclockwise 135° asynchronous rolling method with a roll speed ratio of 1:1.2 should be an ideal strategy in obtaining finer grains. Unfortunately, nevertheless, the maximum degree of the bad plate shape is generated after forging by clock asynchronous rolling with a speed ratio of 1:1.2. As a consequence, clock counterclockwise 135° snake rolling with a 30 mm offset distance was proposed on the basis of a rolling speed ratio of 1:1.2, which perfectly corrected the warping plate shape caused by clock asynchronous rolling. What is more important, the minimum damage value of 1.60 was achieved accordingly. Meanwhile, the ES value increased in the core of the plate for the clock counterclockwise 135° snake rolling with all of the four offset distances compared to clock synchronous rolling. This study should be significantly conducive to guidance on setting process parameters in the industrial production of hot rolling metal or alloy targets.

Collective oscillations in a three-dimensional spin model with non-reciprocal interactions

Abstract We study the onset of collective oscillations at low temperature in a three-dimensional spin model with non-reciprocal short-range interactions. Performing numerical simulations of the model, the presence of a continuous phase transition to global oscillations is confirmed by a finite-size scaling analysis, yielding values of the exponents β and ν compatible with both the three-dimensional XY and Ising equilibrium universality classes. By systematically varying the interaction range, we show that collective oscillations in this spin model actually result from two successive phase transitions: a mean-field phase transition over finite-size neighborhoods, which leads to the emergence of local noisy oscillators, and a synchronization transition of local noisy oscillators, which generates coherent macroscopic oscillations. Using a Fokker–Planck equation under a local mean-field approximation, we derive from the spin dynamics coupled Langevin equations for the complex amplitudes describing noisy oscillations on a mesoscopic scale. The phase diagram of these coupled equations is qualitatively obtained from a fully-connected (mean-field) approximation. This analytical approach allows us to clearly disentangle the onset of local and global oscillations, and to identify the two main control parameters, expressed as combinations of the microscopic parameters of the spin dynamics, that control the phase diagram of the model.

Strong coupling yields abrupt synchronization transitions in coupled oscillators

Coupled oscillator networks often display transitions between qualitatively different phase-locked solutions—such as synchrony and rotating wave solutions—following perturbation or parameter variation. In the limit of weak coupling, these transitions can be understood in terms of commonly studied phase approximations. As the coupling strength increases, however, predicting the location and criticality of transition, whether continuous or discontinuous, from the phase dynamics may depend on the order of the phase approximation—or a phase description of the network dynamics that neglects amplitudes may become impossible altogether. Here we analyze synchronization transitions and their criticality systematically for varying coupling strength in theory and experiments with coupled electrochemical oscillators. First, we analyze bifurcations analysis of synchrony and splay states in an abstract phase model and discuss conditions under which synchronization transitions with different criticalities are possible. In particular, we show that such conditions can be understood by considering the relative contributions of higher harmonics to the phase dynamics. Second, we illustrate that transitions with different criticality indeed occur in experimental systems. Third, we highlight that the amplitude dynamics observed in the experiments can be captured in a numerical bifurcation analysis of delay-coupled oscillators. Our results showcase that reduced order phase models may miss important features that one would expect in the dynamics of the full system. Published by the American Physical Society 2024

The Impact of UNESCO MGIEP Digital Teacher Training on Nigerian Educators' Digital Pedagogy Competence and Confidence

This study explores Nigerian educators’ perceptions of digital pedagogy competence and the impact of a UNESCO MGIEP digital teacher training course. The study employs a validated survey and paired sample t-tests to assess the efficacy of a 5-week intervention delivered through synchronous and asynchronous modes. The findings reveal statistically significant improvements in educators' digital pedagogy competence and confidence across multiple domains following Digital Teacher Training, with substantial increases in mean scores from pre-test to post-test (p &lt; .001) and moderate to large effect sizes (Cohen's d ranging from 0.430 to 1.062). These results demonstrate the intervention's efficacy in enhancing educators' proficiency in leveraging digital technologies for instruction, assessment, and student engagement, although a marginal decline was observed in facilitating student self-monitoring through digital means.

Is the Term "Food Consistency" Used Consistently in Consumer Science? An Exploratory Study of Consumer Association and Conceptualization.

The post-pandemic context has changed the modes for collecting data in sensory and consumer science. The objectives of this research were to analyze consumers' associations of food consistency and to study two virtual modes of the Free Word Association test (FWA). This test was administered to 209 consumers (180 women, 29 men, 18-45 years old) asynchronously (i.e. self-administered) and synchronously (i.e. face to face interviews). The Cognitive Salience Index (CSI) was calculated, and the structure of the social representation was analyzed. Correspondence analysis showed that food consistency was a mixture of concepts related to structure, hardness and several aspects of auditory (e.g., Crunchy, Crispy), tactile (e.g. Smooth, Spreadable) and oral texture (e.g., Creamy, Gummy). Slightly consistent food was associated with something soft, liquid or semisolid, and very consistent food to something hard and resistant. Consistent food was more related to "very" than to "slightly consistent." The CSI depended on the stimulus presented (p < 0.05). Regarding the social representation structure, the central core had the highest CSI for all stimuli (CSI ≥ 0.13, p < 0.05). Consumers defined "very consistent, consistent and slightly consistent food" by naming more foods in the synchronous mode than in the asynchronous one. In the asynchronous mode, consumers took more time to complete the test. The virtual FWA test (asynchronous or synchronous) showed some differences in the associations of term consistency, due to the lack of spontaneity in the first minute. It is important to adjust the methodologies to standardize the times in both modes.