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The widespread adoption of Industry 4.0 technologies is revolutionising how manufacturing operations are managed and done. This revolution drives manufacturing practitioners to reevaluate their current manufacturing planning and control (MPC) strategies to maintain global competitiveness. The production and intralogistics (PiL) operations within traditional MPC systems are organised separately, which results in inferior overall solutions. PiL operations in a single factory are inherently coupled and interact with each other throughout the entire process, which needs synchronous organisation and operations. This paper introduces a novel concept of operations twins (OT), with vertical twinning and horizontal twining, for achieving PiL synchronisation by leveraging Industry 4.0 technologies and innovative operations management strategies. An Internet-of-Things (IoT)-based vertical twinning method is developed for real-time object-level data collection and information-sharing between PiL. A horizontal twinning mechanism is proposed to support real-time coordination of production and intralogistics operations with real-time information-sharing. A numerical study is carried out, and the results show that OT outperforms the widely used static and dynamic methods regarding the overall stability and typical measures such as makespan, average manufacturing time, and average tardiness under different levels of uncertainties. [ABSTRACT FROM AUTHOR]

This research introduces a novel damped alternating current (DAC) testing methodology, which integrates an enhanced DAC generator with a pulse‐based distributed partial discharge (PD) detection technique. The advanced DAC generator is designed without the need for high voltage (HV) solid‐state switches, thereby offering a cost‐effective solution for field‐testing voltage generation through a direct current–alternating current conversion approach. To meet the demand for high instantaneous power, a capacitor bank is employed as the power supply. Furthermore, the implementation of a distributed PD detection technique enhances sensitivity and eliminates limitations associated with cable length. To minimize the construction costs of the distributed PD‐detection system, a pulse synchronization technique has been employed. Efforts to reduce the system's weight were informed by simulations, resulting in the design and development of a prototype weighing 850 kg for a 64/110 kV power cable. The reduction in the number of HV solid‐state switches contributes to significant cost savings, amounting to tens of thousands of dollars, when compared to conventional DAC generators. Laboratory and field tests validated the effectiveness of the cost‐efficient DAC testing methodology. [ABSTRACT FROM AUTHOR]

The mass customisation strategy is needed by manufacturing companies to face the increasing variety and unpredictability of products required by customers. However, mass customisation may increase the complexity of managing manufacturing and production logistics activities, for example due to reduced product batch sizes. The synchronisation of material flows within the factory is emerging as a way to address this complexity, as it enables an effective and efficient implementation of mass customisation. Indeed, the fourth Industrial Revolution introduces new digital levers, which can be combined with traditional managerial levers to achieve the synchronisation of material flows within the factory. This study contributes to the rising stream of research on this topic. A systematic literature review was conducted, leading to the development of a classification framework of the levers supporting the synchronisation of material flows. The identified managerial levers are: storage of materials, feeding policy, and scheduling. The digital levers are: materials tracking, process tracking, data analytics, and assistance systems. The developed framework was operationalised in four industrial cases and applied as a tool to map their levers related to the synchronisation of material flows. [ABSTRACT FROM AUTHOR]

Hybridisation is an evolutionary process that generates genetic diversity in organisms. However, the relationship between reproductive features, such as spawning synchronisation and gamete compatibility, and the degree of introgression leading to hybridisation are poorly understood. The reef-building coral Acropora spp. have a complex evolutionary history, and the link between their ecology, life-history traits, and potential to hybridise is disputed. Here, we examined the relationship among the reproductive features involved in the intercrossing of three species, Acropora florida, Acropora gemmifera, and Acropora intermedia, at two sites: Akajima and the Sesoko islands in southern Japan. Although the examined species showed synchronous spawning and high rates of gamete compatibility, spawning synchronisation and gamete compatibility were less strongly associated with high rates of interbreeding among the three species. Model-based genetic clustering and site-pattern frequency-based tests with single nucleotide polymorphisms supported genetic admixture among the three species in each location. Demographic analyses using fastsimcoal implied that the admixture among the three species in each location might have occurred in the past (> 2,000 generations) and recently (< 50 generations). Furthermore, the recent admixture of these three species is potentially associated with heavy bleaching events and population declines. The principal component analysis, structure, and fastsimcoal showed that the extensive admixture of A. intermedia and A. gemmifera on Sesoko Island occurred recently. Therefore, gamete interactions that lead to hybridisation in the field must be clarified. Furthermore, the connectivity between the two locations needs to be identified; however, our results implied that population fluctuations could be associated with introgression. [ABSTRACT FROM AUTHOR]

In recent years, Conversational Analysis (CA) has seen an increasing interest in longitudinal studies (Deppermann & Pekarek Doehler, 2021). The recurrent experience of interactional practices leads interactants to develop routines that may sediment into entrenched patterns over time (Dreyer, 2022). Longitudinal CA thus aims to track the emergence and sedimentation of interactional practices over time. In this contribution, we analyse interactional practices of participation in play-situations. Participation in joint activities is a universal form of human sociality (Goodwin & Goodwin, 2005). Here, we focus on how children perform their own agentive participant's work and how mothers support their children in doing so. Investigating a longitudinal data set of mother-child play-interactions at ages 1 and 5, we ask whether participation patterns emerge as early as in the first year and are sedimented in the fifth year, as well as whether the synchronisation of embodied action provides crucial resources for the achievement of active participation in joint activities. [ABSTRACT FROM AUTHOR]

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Copyright of e & i Elektrotechnik und Informationstechnik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract This research introduces a novel damped alternating current (DAC) testing methodology, which integrates an enhanced DAC generator with a pulse‐based distributed partial discharge (PD) detection technique. The advanced DAC generator is designed without the need for high voltage (HV) solid‐state switches, thereby offering a cost‐effective solution for field‐testing voltage generation through a direct current–alternating current conversion approach. To meet the demand for high instantaneous power, a capacitor bank is employed as the power supply. Furthermore, the implementation of a distributed PD detection technique enhances sensitivity and eliminates limitations associated with cable length. To minimize the construction costs of the distributed PD‐detection system, a pulse synchronization technique has been employed. Efforts to reduce the system's weight were informed by simulations, resulting in the design and development of a prototype weighing 850 kg for a 64/110 kV power cable. The reduction in the number of HV solid‐state switches contributes to significant cost savings, amounting to tens of thousands of dollars, when compared to conventional DAC generators. Laboratory and field tests validated the effectiveness of the cost‐efficient DAC testing methodology.

Film historians have long known that the version of Carl Theodor Dreyer's La Passion de Jeanne d'Arc (1928) shown at its French premiere was heavily censored by the state and the Catholic church. Exactly what was cut, however, has never been entirely clear, meaning that almost all of the critical literature about the subject has been forced to accept the testimony of those who claim to have seen it at the time. An overlooked source that would help resolve the debate is the score commissioned for its Paris premiere. It includes vital evidence in the form of intertitles and actions that correspond to a print acquired by the British Film Institute in 1947. A detailed comparison of screen and musical time convincingly demonstrates that the 1947 print is a copy of the censored version, and a broader analysis of empathetic musical gesture and specially written lyrics for choir and soloists supports that contention. This analysis underlines the valuable contribution that film-music studies can make to film history in helping reveal for the first time exactly what it was to which the authorities objected in Dreyer's famous film. [ABSTRACT FROM AUTHOR]

This paper aims to deal with Robin boundary synchronisation control for a kind of nonlinear coupling reaction–diffusion neural networks (RDNNs) with non-identical nodes. Some novel sufficient conditions involving the parameters of event-triggered mechanism are proposed to achieve synchronisation of this RDNNs. By utilising Lyapunov's method and Wiringer inequality, the error closed-loop systems with the designed event-triggered controller are proved to be well-posed and the RDNNs to be exponentially synchronised with target system. Moreover, Zeno behaviour of event-triggered control is avoided. Finally, the effectiveness of our theoretical results is verified by one numerical example. [ABSTRACT FROM AUTHOR]

The application and uses of drones in all areas are continuously rising, especially in civilian use cases. This increasing threat requires reliable drone surveillance in urban environments. Radar is the obvious candidate with its ability to detect small objects at range, in all weather conditions. The use of an L‐band networked radar for urban sensing of S‐UAS targets is explored. Small echoes from S‐UAS places a premium on synchronisation, which is the fundamental key for high performance networked radar. The effect of timing errors on the operation of the network radar is investigated theoretically and experimentally, and the processing tools for synchronising data based on the direct signal returns of the transmitter are developed. Also, drone detection using bistatic L‐band staring radar is achieved both in simulation and then in real field trials where the SNR and detection performance are computed and analysed. The updated direct signal synchronisation method for bistatic staring radar is shown to provide comparable SNR and positional accuracy for S‐UAS targets as the monostatic staring radar. [ABSTRACT FROM AUTHOR]

The paper presents a Markovian queueing model for assessing the performance of synchronisation between stations in a production system. The system at hand consists of K distinct buffers, each buffer storing an item that is needed for the next production stage. Departures are immediate when all items are present. Due to the presence of multiple buffers, there is no reasonably fast way to calculate the stationary distribution of the Markov chain. Therefore, we focused on the series expansion of the stationary distribution in terms of the arrival rate. We provide a fast algorithm for calculating these terms. Comparing our results with stochastic simulation, we show that the expansion approach converges to the simulated values for a wide range of arrival rates. [ABSTRACT FROM AUTHOR]

Due to the proliferation of video-based applications, there is a high demand for automated systems to support various video-based tasks that are free from human intervention, i.e., manual tagging. In this paper, we present a novel approach for detecting the presence of overlap between two videos by exploiting their corresponding audio signals, which is a crucial preprocessing step for audio, and further video alignment and synchronisation. Several existing approaches have limitations related to timestamps, overlapping regions, and the length of video clips. For the proposed work, we target the challenging scenario consisting of simultaneously recorded videos in an unconstrained manner by multiple users attending performance events. xOur work is an attempt towards developing a robust framework that not only considers noisy components present in the audio but is also free from the limitations mentioned above. We compare our framework with several other existing approaches. Our proposed framework outperforms other approaches by an average of 13.71% in terms of accuracy. [ABSTRACT FROM AUTHOR]

Simple Summary: It is widely acknowledged that dogs synchronise their behaviours with those of humans. In this article, we delve into the neural and cognitive bases of this form of behavioural adjustment. Using knowledge of cerebral processes underlying behavioural synchronisation in humans, namely motor resonance and the activation of mirror neurons, we investigated whether dogs' behavioural synchronisation with humans could be based on similar mechanisms. In humans, both perceiving and executing an action activate the motor representations of that action. Motor resonance occurs when motor representations of an action are simultaneously activated in both the observer and the individual being observed. Mirror neurons are the neural substrate for motor resonance as these motor neurons activate both when an individual performs or perceives an action. Our review of existing literature shows that motor resonance could occur in dogs, suggesting that dogs' behavioural synchronisation with humans relies on the activation of both human and canine mirror neurons. Behavioural studies suggest but do not prove the existence of motor resonance between the two species, and thus further research is needed to confirm this hypothesis. Revealing the mechanisms underlying dogs' behavioural synchronisation with humans would contribute to a better understanding of how dogs and humans have evolved together since the beginning of their cohabitation. Dogs' behavioural synchronisation with humans is of growing scientific interest. However, studies lack a comprehensive exploration of the neurocognitive foundations of this social cognitive ability. Drawing parallels from the mechanisms underlying behavioural synchronisation in humans, specifically motor resonance and the recruitment of mirror neurons, we hypothesise that dogs' behavioural synchronisation with humans is underpinned by a similar mechanism, namely interspecific motor resonance. Based on a literature review, we argue that dogs possess the prerequisites for motor resonance, and we suggest that interspecific behavioural synchronisation relies on the activation of both human and canine mirror neurons. Furthermore, interspecific behavioural studies highlight certain characteristics of motor resonance, including motor contagion and its social modulators. While these findings strongly suggest the potential existence of interspecific motor resonance, direct proof remains to be established. Our analysis thus paves the way for future research to confirm the existence of interspecific motor resonance as the neurocognitive foundation for interspecific behavioural synchronisation. Unravelling the neurocognitive mechanisms underlying this behavioural adjustment holds profound implications for understanding the evolutionary dynamics of dogs alongside humans and improving the day-to-day management of dog–human interactions. [ABSTRACT FROM AUTHOR]

In this paper, we use two Fractional-Order Chaotic Systems (FOCS)—one for the sender and one for the receiver—to determine the optimal synchronisation for a secure communication technique. With the help of the Step-By-Step Sliding-Mode Observer (SBS-SMO), this synchronisation is accomplished. An innovative optimisation method, known as the artificial Harris hawks optimisation (HHO), was employed to enhance the observer's performance. This method eliminates the random parameter selection process and instead selects the optimal values for the observer. In a short amount of time, the secret message that could have been in the receiver portion (signal, voice, etc.) was successfully recovered using the proposed scheme. The experimental validation of the numerical results was carried out with the assistance of an Arduino microcontroller and several electronic components. In addition, the findings of the experiments were compared with the theoretical calculations, revealing a satisfactory level of agreement. [ABSTRACT FROM AUTHOR]

Abstract The massive perception data based on efficient analysis and intelligent decision have put forward higher requirements for high‐precision time synchronisation with the construction and development of smart power grid. However, multi‐reference source time‐frequency synchronisation of power system only selects the best method after comparison, which cannot make the most efficient use of the existing resources. It also cannot meet the need for high‐precision time synchronisation of future power system. The existing multi‐reference source synthesis algorithms cannot take into account both long‐term stability and high‐precision synchronous output. This article presents a multi‐reference source weighted improved noise model and the high‐precision output method. The multi‐reference source error after classification is eliminated by leading into classification vector and classification coefficient. The synthesised frequency offset or the time precision of output can be optimised as the objective function by weighted classification algorithm and genetic algorithm. A simulation example based on the synthesis of two satellite system clock sources and three local caesium reference sources shows that the peak value of long‐term output accuracy is controlled within 10 ns after classification weighted synthesis and optimisation, which is better than that of any single reference source.

Abstract Precise energy management in distribution power system requires high‐precision time synchronization among large‐scale deployed devices. Multiple clock sources‐based time synchronization possesses advantages of reliability, high precision, and robustness, but still faces several challenges such as coupling between time synchronization error and delay, as well as different timescales between clock source and clock weight optimization. In this paper, a multi‐clock source time synchronization model is constructed and a problem is formulated to minimize the synchronization error and delay through jointly optimizing large‐timescale clock source selection and small‐timescale weight selection. A reinforcement learning‐based multi‐timescale multi‐clock source time synchronization algorithm named RL‐M2 is proposed to solve the formulated problem from a learning perspective. Besides, a lossless switching method is proposed to address the switching problem for multiple clock sources. Simulation results demonstrate the superior performance of RL‐M2 and the lossless switching method in time synchronization delay and error.

Abstract The definition of scaled p‐norm and its properties are given here. Compared with the norm‐normalized sign function, using scaled p‐norm in the controller design can not only achieve the time‐synchronized stability of non‐linear dynamic systems, but also improve the convergence rate of the system. Besides, the scaled p‐norm is applied to design the consensus protocol for multi‐agent systems, which enables the states of all agents to achieve fast time‐synchronized consensus. The simulation results demonstrate the superiority of this method in improving the convergence rate of the system.

Control and synchronisation of chaotic systems have received much attention due to their various potential applications. In this paper, the predefined-time master–slave synchronisation of two chaotic systems is investigated. With the help of two different predefined-time stability theorems, two controllers are designed to achieve the predefined-time synchronisation of two nonidentical chaotic systems. Then based on inequality techniques and a Lyapunov function, some new sufficient criteria are obtained to ensure that two nonidentical chaotic systems achieve predefined-time synchronisation. Finally, numerical examples are given to show the effectiveness of our new results. [ABSTRACT FROM AUTHOR]

Societies are becoming increasingly aware that they owe their emergence, wealth and industrialisation to their influence as a geophysical force. Social and environmental scientists have analysed the genesis of this self-reflection and pointed to past failures that have led to this predicament. Following the gradually beginning research on differing temporalities, temporal practices and time regimes in the climate change discourse, this article shifts the perspective from past obstacles to possibilities for shaping the future. We historically reconstruct the emergence of interfaces of future co-production and theorise how these enable the imagination, communication and negotiation of climate futures. We conceptualise (1) world organisations as permanent interfaces of future co-production that bring together disparate temporal perspectives, (2) world events as temporary settings that accelerate the production of climate futures, and (3) world objects as mobile webs of meaning that travel between social worlds. [ABSTRACT FROM AUTHOR]

The boundary synchronisation problem of fractional-order fuzzy reaction–diffusion BAM neural networks with leakage delay is investigated. A novel adaptive boundary controller, Neumann boundary condition, and fuzzy feedback MIN and MAX templates of nonlinear dynamic fuzzy modelling are employed. We developed adaptive sufficient criteria to check the asymptotic stability of error dynamical system by using suitable Lyapunov functional, Wirtinger's inequality and LMI method, which guarantee the drive-response dynamical systems achieve the synchronisation. Meanwhile, two different controllers, adaptive full-domain and boundary controllers are developed. At last, numerical simulations are presented to demonstrate the feasibility of the theoretical results. [ABSTRACT FROM AUTHOR]

A reliable neuron model can accurately estimate and predict complex bioelectrical activities, which provides potential guidance and assistance for designing neurocomputing science and intelligent sensors. To disclose the regulation mechanism of heterogeneous electromagnetic fields on action potential, a non-smooth memristive Hindmarsh–Rose (HR) neuron model is established by introducing a three-stage flux-controlled memristor. Based on the theory of flow switchability, the sufficient and necessary conditions for crossing, grazing and sliding motions of the system are presented and verified. It is particularly interesting that the existence and stability of the equilibrium point of the system by exciting bipolar pulse current have time-varying behaviour. Further, extensive coexisting attractors are discovered by multiple numerical tools. Importantly, the switching dynamics of the coexisting firing modes involving period and chaos are qualitatively discussed by calculating the normal vector field G-functions. Moreover, a Hamilton energy adaptive controller is designed to efficiently achieve the complete synchronisation of the coupling neurons consisting of the non-smooth system via unidirectional synaptic connections under mismatched parameters. These obtained results provide potential theoretical guidance for the lesion, control and treatment of neuron-related diseases. [ABSTRACT FROM AUTHOR]

Objective: The article aims to investigate the synchronisation of metropolitan house prices from 2000 to 2020 based on novel empirical data. We applied several econometric procedures to address the cyclicity of housing markets. Research Design & Methods: Using a unique dataset of over four million offers, we investigated the synchronisation of 18 regional housing markets in Poland from 2000 to 2020. The study used spectral analysis. Findings: The study proved the strong synchronisation of housing cycles in Polish regional housing markets. Moreover, when the cycle amplitude was considered, the econometric analysis showed regional disparities in the cyclical behaviour of housing prices. According to the research, Lublin and Opole had the lowest housing cycle magnitude, and Gdańsk, Katowice, and Łódź had the largest magnitude. Implications & Recommendations: The information about housing cycles has important policy implications. Housing wealth effects generated by cyclical house prices may be more persistent than financial wealth effects. Consequently, they may substantially affect consumption dynamics. Therefore, precisely identifying market cycles and differences in cycle synchronisation is vital when constructing an effective, selective, and well-timed monetary policy. Contribution & Value Added: The research narrows the knowledge gap on the synchronisation of housing markets in an emerging economic environment. With their distinct institutional structures, Eastern European countries have little knowledge of this issue. [ABSTRACT FROM AUTHOR]

Precise energy management in distribution power system requires high‐precision time synchronization among large‐scale deployed devices. Multiple clock sources‐based time synchronization possesses advantages of reliability, high precision, and robustness, but still faces several challenges such as coupling between time synchronization error and delay, as well as different timescales between clock source and clock weight optimization. In this paper, a multi‐clock source time synchronization model is constructed and a problem is formulated to minimize the synchronization error and delay through jointly optimizing large‐timescale clock source selection and small‐timescale weight selection. A reinforcement learning‐based multi‐timescale multi‐clock source time synchronization algorithm named RL‐M2 is proposed to solve the formulated problem from a learning perspective. Besides, a lossless switching method is proposed to address the switching problem for multiple clock sources. Simulation results demonstrate the superior performance of RL‐M2 and the lossless switching method in time synchronization delay and error. [ABSTRACT FROM AUTHOR]

The definition of scaled p‐norm and its properties are given here. Compared with the norm‐normalized sign function, using scaled p‐norm in the controller design can not only achieve the time‐synchronized stability of non‐linear dynamic systems, but also improve the convergence rate of the system. Besides, the scaled p‐norm is applied to design the consensus protocol for multi‐agent systems, which enables the states of all agents to achieve fast time‐synchronized consensus. The simulation results demonstrate the superiority of this method in improving the convergence rate of the system. [ABSTRACT FROM AUTHOR]

Sexual conflict has long been perceived as a solid background for the evolution of parental care. Recent studies, however, highlight the importance of cooperation between the parents, especially in socially monogamous systems. Here, we examined parental performance of a small monogamous passerine with bi-parental care, the Eurasian Reed Warbler (Acrocephalus scirpaceus, RW), looking at the issue from the perspective of parents' cooperation. Using accurate and non-invasive video data on parent chick provisioning from 78 nests varying in brood size, we found some evidence of parents cooperation: both parents similarly adjusted their feeding rate to brood size, and the higher was their both contribution, the better was chicks condition (expressed by defecation rate). However, contrary to our expectations (based on premises from similar studies on other bird species) we did not find evidence for frequent and active synchronisation of nest visits. Importantly, we found a negative relationship between synchronisation level and chick body condition, suggesting that synchronisation may actually not be that beneficial in the study system. The results are surprising and highlight the importance of studying various species to understand mechanisms behind cooperation of partners in the bi-parental care system. Significance statement: Biparental care has long been viewed in the context of conflict between the breeding partners, and only recently they are considered cooperating agents caring together for the common offspring. Nevertheless, studies applying such a perspective are still scarce and there is a pressing need to test different species. Using video data on chick provisioning by Reed Warbler parents, we found evidence of partner cooperation: both parents adjusted their feeding rate to the number of nestlings, and the higher was their joint contribution, the better was offspring condition. Parents did not synchronise their nest visits more compared to randomly generated visits, but we found that synchronisation level negatively affected chick condition. Our results highlight the need to consider various species to fully understand mechanisms behind cooperation of breeding partners. [ABSTRACT FROM AUTHOR]

Abstract Due to the implementation bottleneck of training data collection in realistic wireless communications systems, supervised learning‐based timing synchronization (TS) is challenged by the incompleteness of training data. To tackle this bottleneck, the computer‐aided approach is extended, with which the local device can generate the training data instead of generating learning labels from the received samples collected in realistic systems, and then construct an extreme learning machine (ELM)‐based TS network in orthogonal frequency division multiplexing (OFDM) systems. Specifically, by leveraging the rough information of channel impulse responses (CIRs), i.e. root‐mean‐square (r.m.s) delay, the loose constraint‐based and flexible constraint‐based training strategies are proposed for the learning‐label design against the maximum multi‐path delay. The underlying mechanism is to improve the completeness of multi‐path delays that may appear in the realistic wireless channels and thus increase the statistical efficiency of the designed TS learner. By this means, the proposed ELM‐based TS network can alleviate the degradation of generalization performance. Numerical results reveal the robustness and generalization of the proposed scheme against varying parameters.

Abstract The technical feasibility of developing an Internet of Things multi‐user communication system is evaluated based on a central digital multiband carrierless amplitude and phase transmitter, which broadcasts data on multiple channels for a number of low‐cost/low‐power devices. It addresses the issue of carrier synchronisation, which is critical in real‐world implementations because of imperfections of devices and the delays of the system. A simulation model for the traditional Costas Loop is presented, along with performance results, which demonstrate the system's ability to synchronise with pull‐in and lock ranges of ±800 and ±900 Hz, respectively. The loop requires 1.194 ms to be in the locked state, allowing the system to lock within 6 symbols period. In addition, the authors measured the performance of the system in the presence of noise and interference from other modulated bands. The results showed that noise and interference did not degrade the system's performance. Although the system was unable to lock when energy was present in adjacent bands, alternative options such as a high order phase‐locked loop and hybrid frequency‐division multiple access and time‐division multiple access, can improve system performance without significantly increasing the cost and complexity of the devices.

This paper deals with adaptive super-twisting (STW) sliding mode control (SMC) algorithm to manage chaotic supply chain system. A multi-echelon supply chain system having parametric perturbations and disturbances is presented to demonstrate chaotic nonlinear dynamical behaviours. When changing input variables slightly in the supply chain system, the predicted outputs will be completely different due to chaotic behaviours with bifurcation. In addition, various uncertainties along with exogenous disturbances make the system dynamics more complex to manage as they propagate both upstream and downstream of the supply chain networks. Particularly, the adaptive STW SMC algorithm has been designed for chaos suppression and synchronisation of the supply chain system. Next, the robust control algorithm with adaptive law for the closed-loop system has been proved by using Lyapunov stability theorem. Then, extensive numerical simulations are conducted to demonstrate the validity of the active control synthesis for optimal operations management of chaotic supply chain networks. The control algorithm based on system theory provides satisfactory performance on achieving chaos suppression and synchronisation of the chaotic supply system. The control system theory can be expanded into new integration software applications for operations management of supply chain networks. Finally, the presented control synthesis with dynamical analysis is essential for strategic decision-makers in the modern supply chain management. [ABSTRACT FROM AUTHOR]

Abstract In this paper, finite‐time cluster synchronization (FTCS) in networks of nonidentical coupled dynamical systems is addressed by introducing a discontinuous interaction rule. This interaction rule overcomes the effect of heterogeneous dynamics among nodes. It is proven that with proper coupling gain, the dynamics of the coupled system converges into the kernal space of the graph Laplacian matrix in finite time. Then sufficient conditions for FTCS are provided. In addition, the discontinuous interactions rule is applied to investigate finite‐time intra‐layer synchronization in multiplex networks.

This paper proposes an improved version of Synchronous Reference Frame (SRF) based phase locked loop (PLL). The conventional SRF-PLL structure is modified and made adaptive using a Least Means Square (LMS) algorithm. The benefit of the proposed scheme is that the tuning of proportional controller (PI) gain parameters can be achieved automatically without having to optimise these parameters manually. The PLL is utilised to track important electrical grid parameters such as phase angle, unit synchronisation templates and voltage magnitude. This performance study investigates several cases such as voltage sag/swell, wide frequency deviation, phase jump, presence of noise and harmonics in the supply voltage. The impact of constant and adaptive PI parameters influencing PLL performance is investigated. Finally, a fair comparison is presented which discusses the proposed adaptive SRF-PLL(ASRF-PLL), conventional fixed gain SRF-PLL, unit template-based synchronisation technique and Delayed Signal Cancellation based PLL (DSC-PLL). [ABSTRACT FROM AUTHOR]

This paper accounts synchronisation of unified chaotic systems using a modified nonlinear active control technique, its circuit analogue circuit implementation, and secure communication. The proposed nonlinear active control approach utilises appropriate states of the unified chaotic systems. The modified nonlinear active control leads to the coupled error dynamics and does not require the external forcing parameters or gains, which differs from the active control techniques reported in the literature. The designed control law ensures the asymptotic stability in large, and the necessary condition is derived using Lyapunov stability theory. Further, the performance of the designed nonlinear active controller is compared based on different time integral performance of the errors with active, adaptive, and sliding mode control techniques. Numerical and circuit simulations are performed in MATLAB and NI-Multisim environments, respectively. Circuit simulated results accord to MATLAB simulation results. Further, unified chaotic system, its synchronisation, and application to secure communication are validated with breadboard circuit/hardware implementation. [ABSTRACT FROM AUTHOR]

This study aimed to determine whether serum metabolite and hormones of ewes with low body condition scores subjected to the melatonin plus progesterone-based protocol (MPE) would be similar to a single progesterone-based protocol (PE) and whether melatonin ear implant supplementation could increase pregnancy rate. Ninety suckled Merino ewes with singleton lamb were equally allocated in two experimental groups (MPE, PE) and a control group (CON) on days 53 ± 3 (D0) postpartum. Ewes in MPE group were subjected to exogenous melatonin plus progesterone-based protocol [Melatonin (day 0) + P4 insertion (day 35) + 500 IU eCG (day 42)]. Ewes in the PE group were subjected to a progesterone-based protocol [P4 insertion (day 35) + 500 IU eCG (day 42)]. Ewes in the CON group received no application. Blood samples (10 ewes/group) were collected to determine serum leptin, cortisol, insulin-like growth factor 1 (IGF-1), beta-hydroxybutyric acid (BHBA), and prolactin levels on days 0, 35, and 42. A pregnancy diagnosis was performed on days 72 and 102. Neither the synchronisation protocol nor the duration of lactation affected body condition score, (BCS; 2.30 ± 0.05), serum leptin (3.49 ± 0.30 ng/mL), cortisol (6.28 ± 1.10 ng/mL), IGF-1 (53.38 ± 2.09 ng/mL) and BHBA levels (0.24 ± 0.02 mmol/L) at the beginning of study (p > 0.05). However, prolactin levels reduced (p = 0.043) by the time (111.80 ± 12.49, 97.40 ± 3.77, 66.30 ± 4.85 ng/mL) in the MPE group. The oestrus response (p < 0.0001) and pregnancy rate (p = 0.018) were higher in the MPE (70%, 30%) and PE (60%, 30%) groups than in the CON group (10%, 3.3%), respectively. In conclusion, adding a melatonin implant to a progesterone-based protocol decreased prolactin levels but did not change other hormones and BHBA levels. Although both synchronisation protocols increased oestrus response and pregnancy rate, melatonin implant did not contribute to the increment of pregnancy rate compared to a single progesterone-based protocol in suckled Merino ewes with low BCS during the early postpartum period. [ABSTRACT FROM AUTHOR]

Due to the implementation bottleneck of training data collection in realistic wireless communications systems, supervised learning‐based timing synchronization (TS) is challenged by the incompleteness of training data. To tackle this bottleneck, the computer‐aided approach is extended, with which the local device can generate the training data instead of generating learning labels from the received samples collected in realistic systems, and then construct an extreme learning machine (ELM)‐based TS network in orthogonal frequency division multiplexing (OFDM) systems. Specifically, by leveraging the rough information of channel impulse responses (CIRs), i.e. root‐mean‐square (r.m.s) delay, the loose constraint‐based and flexible constraint‐based training strategies are proposed for the learning‐label design against the maximum multi‐path delay. The underlying mechanism is to improve the completeness of multi‐path delays that may appear in the realistic wireless channels and thus increase the statistical efficiency of the designed TS learner. By this means, the proposed ELM‐based TS network can alleviate the degradation of generalization performance. Numerical results reveal the robustness and generalization of the proposed scheme against varying parameters. [ABSTRACT FROM AUTHOR]

The technical feasibility of developing an Internet of Things multi‐user communication system is evaluated based on a central digital multiband carrierless amplitude and phase transmitter, which broadcasts data on multiple channels for a number of low‐cost/low‐power devices. It addresses the issue of carrier synchronisation, which is critical in real‐world implementations because of imperfections of devices and the delays of the system. A simulation model for the traditional Costas Loop is presented, along with performance results, which demonstrate the system's ability to synchronise with pull‐in and lock ranges of ±800 and ±900 Hz, respectively. The loop requires 1.194 ms to be in the locked state, allowing the system to lock within 6 symbols period. In addition, the authors measured the performance of the system in the presence of noise and interference from other modulated bands. The results showed that noise and interference did not degrade the system's performance. Although the system was unable to lock when energy was present in adjacent bands, alternative options such as a high order phase‐locked loop and hybrid frequency‐division multiple access and time‐division multiple access, can improve system performance without significantly increasing the cost and complexity of the devices. [ABSTRACT FROM AUTHOR]