Synchronization Methodology Research Articles

Design and Offshore Testing of the Nodal Deep Sea Seismic–Electromagnetic Joint Acquisition System

Abstract This paper presents the design, development, and offshore validation of OBSEM, a pioneering marine seismic-electromagnetic joint acquisition system aimed at enhancing comprehensive underwater observation capabilities. The system integrates the functionalities of ocean bottom seismometers (OBS) and ocean bottom electro-magnetometers (OBEM), enabling synchronous collection of seismic and electromagnetic signals. Detailed are the structural components, including sensors, data acquisition unit, power supply, clock synchronization system, and signal conditioning techniques employed to augment the signal-to-noise ratio of low-frequency electromagnetic signals. Noteworthy is the clock synchronization methodology employing a hybrid GPS and atomic clock configuration for precise temporal alignment. Furthermore, an automatic leveling system is engineered to maintain the seismometer’s horizontal orientation, crucial for ensuring data fidelity. The integration of seismic and electromagnetic data offers a significant advancement in marine geophysical surveys, promising heightened exploration efficacy and inversion accuracy. Offshore trials conducted in the South China Sea affirm the efficacy of OBSEM, with future endeavors aimed at deep-sea validation.

A hybrid framework for latency compensation in remote testing of automotive electronic control units

As the number of electronic control units (ECUs) in vehicles continues to grow, exchanging physical components between original equipment manufacturers (OEMs) and ECU suppliers presents logistical challenges, impeding the pace of development and leading to accumulation of costs. In this work, we introduce a conceptual framework that enables remote testing of geographically dispersed ECUs over the Internet. Pertinent to the Internet of Things (IoT) sphere, where interconnection of distributed components is hampered by the inherent challenges of latency, we propose a hybrid synchronous methodology that combines asynchronous test management with time synchronization mechanisms to mitigate the delay impact within the distributed environment. Additionally, we discuss challenges and prospects associated with this approach.

A high‐precision timing and frequency synchronization algorithm for multi‐h CPM signals

AbstractIn the context of certain specific digital communication systems, where there are limitations such as spectral resources and energy availability, continuous phase modulation (CPM) emerges as an appealing choice among various modulation methods. Among CPM signals, multi‐h CPM is particularly noteworthy for its ability to address these constraints within the realm of single‐carrier and constant‐envelope waveforms. At the physical layer, the design of a multi‐h CPM receiver necessitates the efficient implementation of timing and frequency synchronization algorithm within a high dynamic environment. So this paper presents an innovative approach for achieving timing and frequency synchronization. To rectify timing offset and mitigate the adverse effects of noise in received signals, a re‐configurable local filter generation method is integrated into the timing synchronization algorithm. Simultaneously, an enhanced least mean square adaptive filter algorithm is applied to address frequency synchronization. A comprehensive series of simulations rigorously evaluates the outcomes of proposed novel synchronization methodology. These analyses demonstrate a notable proximity between the synchronization errors of proposed algorithm in this paper and the performance benchmark set by the modified Cramer–Rao bound. The proposed synchronization technology also exhibits the capability to substantially reduce the bit error rate, thereby effectively enhancing demodulation performance in multi‐h CPM receivers.

Concordance of judgement: A tool to foster the development of professionalism in dentistry.

Developing professionalism notably involves learning how to make professional judgements in ambiguous situations. The Concordance of Judgement Test (CJT) is a learning tool that was proposed to develop professionalism competencies, but it was never performed in dentistry or used with a synchronous methodology. The present study evaluated the feasibility of the use of CJT in the context of dental education, to foster professionalism and stimulate reflexivity and discussion. After different steps of optimization, a questionnaire presenting 12 vignettes was submitted to 33 Canadian students. Second, after an additional optimization, a questionnaire of 7 vignettes was submitted to 87 French students. An immediate educational feedback was proposed after each vignette to promote reflexivity and discussions during the experience. The overall experience of the students was reported as good, thanks to the feedback of real-life situations. This promoted reflexivity and stimulated discussion between students and educators regarding professionalism issues. The students considered CJT as a relevant and well-adapted tool, and reported positive feelings regarding the inter-university aspect of the activity. The mean score of the panel members was close to 80/100 and the mean score of the students was 5 to 10 points lower, which is in agreement with docimological performance. The results suggested that the use of CJT in a synchronous way was a feasible and relevant tool to motivate the students to improve their professionalism, and to stimulate their reflexivity and discussion. The students reported positive experience with CJT, and we believe that this tool can be integrated in the dental curriculum.

Analysis and Chaos Control and Synchronization of the Nonlinear Newton–Leipnik System Via Feedback Adaptive Control Techniques

This paper presents the system analysis and chaos control synchronization of the Newton–Leipnik system. Uniqueness and existence solutions (equilibrium points or fixed points) of Newton–Leipnik system have been discussed and local analysis of the system at each equilibrium points is studied. Lyapunov exponents and Kaplan–Yorke dimensions, bifurcation diagrams and poincare sections are analyzed and plotted to establish the presence of chaos in the system. Control feedback techniques are simulated in the nonlinear Newton–Leipnik system. Controlling chaos of systems to find the desired result are established. Synchronization methodologies of two identical integer-order Newton–Leipnik systems are yielded applying adaptive control technologies which have been verified through plotting the graphs of tracking the trajectories of master to slave systems, parameter identification results and synchronization of error dynamics diagrams of Newton–Leipnik systems. These findings offer valuable insights and tools applicable to various scientific and technological domains. These results highlight the originality of our study and deepen our understanding of chaos in Newton–Leipnik systems, offering practical applications and enhanced insights for researchers and scientists in chaos analysis.

ISPO Policy on Palm Oil Industry and Biodiesel Development in North Aceh

The total area of oil palm plantations in Aceh Utara Regency is 33,781.64 hectares, managed and operated by 11 oil palm plantation companies. In accordance with the Regulation of the Minister of Agriculture Number 11/Permentan/Ot.140/3/2015 regarding the Indonesian Sustainable Palm Oil Certification System (ISPO), the Government of Aceh Utara Regency has formulated a vision for the palm oil industry within its jurisdiction. This vision is centered around sustainability and its influence on the growth of the biodiesel sector in Aceh Utara Regency. To achieve this, the government encourages the palm oil industry to adopt ISPO certification. This research aims to analyze and describe the challenges, roles, and initiatives undertaken by the Government in Aceh Utara Regency to promote ISPO certification within the palm oil industry. The research employs an empirical juridical approach, encompassing the identification of research subjects, a statutory analysis, and horizontal and vertical synchronization methodologies to address the implementation of ISPO certification. The results of study reveal that the Government of Aceh Utara Regency has actively motivated palm oil plantation entrepreneurs to swiftly pursue ISPO certification. The government has established a dedicated team and allocated funds to expedite the implementation of ISPO.

Chaos Controllability in Non-Identical Complex Fractional Order Chaotic Systems via Active Complex Synchronization Technique

In this paper, we primarily investigate the methodology for the hybrid complex projective synchronization (HCPS) scheme in non-identical complex fractional order chaotic systems via an active complex synchronization technique (ACST). Appropriate controllers of a nonlinear type are designed in view of master–slave composition and Lyapunov’s stability criterion (LSC). The HCPS is an extended version of the previously designed projective synchronization scheme. In the HCPS scheme, by using a complex scale matrix, the system taken as slave system is asymptotically synchronized with another system taken as the master system. By utilizing a complex scale matrix, the unpredictability and security of communication are increased along with image encryption. An efficient computational method has been employed to validate and visualize the HCPS method’s efficacy by performing numerical simulation outcomes in MATLAB (version 2021).

On the Challenges of Acoustic Energy Mapping Using a WASN: Synchronization and Audio Capture

Acoustic energy mapping provides the functionality to obtain characteristics of acoustic sources, as: presence, localization, type and trajectory of sound sources. Several beamforming-based techniques can be used for this purpose. However, they rely on the difference of arrival times of the signal at each capture node (or microphone), so it is of major importance to have synchronized multi-channel recordings. A Wireless Acoustic Sensor Network (WASN) can be very practical to install when used for mapping the acoustic energy of a given acoustic environment. However, they are known for having low synchronization between the recordings from each node. The objective of this paper is to characterize the impact of current popular synchronization methodologies as part of the WASN to capture reliable data to be used for acoustic energy mapping. The two evaluated synchronization protocols are: Network Time Protocol (NTP) y Precision Time Protocol (PTP). Additionally, three different audio capture methodologies were proposed for the WASN to capture the acoustic signal: two of them, recording the data locally and one sending the data through a local wireless network. As a real-life evaluation scenario, a WASN was built using nodes conformed by a Raspberry Pi 4B+ with a single MEMS microphone. Experimental results demonstrate that the most reliable methodology is using the PTP synchronization protocol and audio recording locally.

Synchronization of kinetic and kinematic hand tasks with electrocorticography and cortical stimulation during awake craniotomies.

Awake craniotomies provide unique and invaluable scientific opportunities for neurophysiological experimentation in consenting human subjects. While such experimentation carries a long history, rigorous reporting of methodologies focusing on synchronizing data across multiple platforms is not universally reported and often not translatable to across operating rooms, facilities, or behavioral tasks. Therefore, here we detail an intraoperative data synchronization methodology designed to work across multiple commercially available platforms to collect behavioral and surgical field videos, electrocorticography, brain stimulation timing, continuous finger joint angles, and continuous finger force production. Our technique was developed to be nonobstructive to operating room (OR) staff and generalizable to a variety of hand-based tasks. We hope that the detailed reporting of our methods will support the scientific rigor and reproducibility of future studies, as well as aid other groups interested in performing related experiments.

A Novel Frequency Measurement Methodology for Clock Synchronization in SPICE-Based Simulators

A Novel Frequency Measurement Methodology for Clock Synchronization in SPICE-Based Simulators

Further results on fixed-time synchronization of the memristor neural networks with impulsive effects

The article is mainly concerned with the fixed-time synchronization (FXTS) of memristor neural networks (MNNs) with time-varying delay and impulsive effects. Using the concept of the average impulsive interval and the comparison principle, some sufficient conditions have been derived to achieve the FXTS of MNNs under the effects of synchronizing impulses and desynchronizing impulses. For the case of desynchronizing impulses, the FXTS of MNNs have not been investigated in literature. Moreover, it has been shown through numerical simulation and theoretical derivation that the estimated settling time is less conservative than that of previous results for MNNs under the effects of synchronizing impulses. Finally, a numerical example is provided to illustrate the effectiveness and superiority of the improved synchronization methodology.

E-Learning Methodology

E-learning is the most important explosion propelled by the internet transformation. It is the use of technology which enables people to learn anytime and anywhere. While teaching can be based in or out of the classrooms, the use of computers and Internet forms the major component of E-learning. It can be termed as a network enabled transfer of skills and knowledge, and the delivery of education is made to a large number of recipients at the same time. E-learning can offer effective instructional methods, such as practising with associated feedback, combining collaboration activities with self-paced study and personalizing learning paths based on learners’ needs. The focus of E-learning is on both asynchronous and synchronous methodology. It investigates three major E-learning tools which are (i) curriculum tools (ii) digital library tools and (iii) knowledge representation tools. This paper reports on the extent to which the effectiveness and students’ attitudes towards E-learning impacts on their learning styles. The paper also reviews literature and gives a scholarly background to the study by reviewing some contributions made by various researchers and institutions on the concept of E-learning. Finally, the paper suggests that synchronous tools should be integrated into asynchronous environments to allow for any-time learning model and gave remark that E-learning needs to improve from various barriers.

Synchronization Analysis of Multiple FitzHugh-Nagumo Noisy and Nonnoisy Neurobiological Networks

In the biological neural bursting and firing synchronization plays a vital role in all neuronal activities that are utilized for making decisions, executing commands, and sending information by neurons and their complex networks in the biological complexed brain. Understanding how the biological brain functionality comes out from different patterns of neuronal transmission between the large group of neural networks stands as one of the enduring challenges of modern neuroscience. This study investigated a methodology for synchronization of multiple single/dual state gap junctions FitzHugh-Nagumo (FHN) drive and slave networks under the condition of external noise. The theory of control was utilized to propose simple and diverse controllers to examine the synchronization problem of the different single and dual state gap junctions coupled nonnoisy and noisy FHN neurobiological drive and slave networks. Control laws are designed to stabilize the error dynamics without direct cancelation and synchronize all the states of both FHN neurobiological drive and slave networks. Sufficient conditions for achieving synchronization in the multiple single/dual state gap junction FHN noisy and nonnoisy neurobiological drive and slave networks were derived analytically using the theory of Lyapunov stability. Furthermore, the proposed controllers have been verified by using five noisy/nonnoisy FHN neurobiological drive and slave networks through numerical simulations.

Category Theory Framework for System Engineering and Safety Assessment Model Synchronization Methodologies

In recent decades, there has been a significant increase in systems’ complexity, leading to a rise in the need for more and more models. Models created with different intents are written using different formalisms and give diverse system representations. This work focuses on the system engineering domain and its models. It is crucial to assert a critical system’s compliance with its requirements. Thus, multiple models dedicated to these assertions are designed, such as safety or multi-physics models. As those models are independent of the architecture model, we need to provide means to assert and maintain consistency between them if we want the analyses to be relevant. The model synchronization methodologies give means to work on the consistency between the models through steps of abstraction to a common formalism, comparison, and concretization of the comparison results in the original models. This paper proposes a mathematical framework that allows for a formal definition of such a consistency relation and a mathematical description of the models. We use the context of category theory, as this is a mathematical theory providing great tools for taking into account different abstraction levels and composition of relations. Finally, we show how this mathematical framework can be applied to a specific synchronization methodology with a realistic study case.

Orbital synchronization of homogeneous mechanical systems with one degree of underactuation

AbstractA methodology for asymptotic orbital synchronization of a set of homogeneous mechanical systems with one degree of underactuation is proposed. A reference model generating a reference orbit is first constructed under the virtual holonomic constraints approach. Then, the synthesis is designed to, first, estimate the state vector of the homogeneous systems, provided that only position measurements are available, and second, to drive the state of the systems to that of the reference model. Due to the synthesis properties, the homogeneous systems converge asymptotically to the reference orbit when there are no disturbances affecting the systems nor the measurements. When disturbances are present, robustness is guaranteed provided that the gain of the closed‐loop systems remains lower than an attenuation level . Numerical results for a set of underactuated cart‐pendulums corroborate the proposed methodology.

A synchronization methodology for 3D offshore wind farm layout optimization with multi-type wind turbines and obstacle-avoiding cable network

Offshore wind farms are increasingly becoming the focus of clean sources market because of the huge energy potential and fast-maturing technology. The existing researches normally optimize the wind turbine layout and two-dimensional cable routing independently. This work focuses on the synchronization optimization of site selection of the offshore wind farm, three-dimensional wind turbine layout and three-dimensional cable network routing based on meta-heuristic algorithms and geographic information systems. Several practical issues, i.e., restricted areas, power generation, cable network and energy loss, are taken into consideration. A two-layer model is proposed. The outer layer model is for the site selection and the wind turbine layout optimization. The inner layer model is for the obstacle-avoiding cable routing optimization. In this stage, the seabed terrain is considered for the first time. The proposed integrated model is complex and non-convex. Thus, a hybrid method including an improved ant colony optimization combined with genetic algorithm, dual-simplex method and Kruskal algorithm is proposed to search the solution more efficiently. The initialization stage of the hybrid method is improved from random assignment to directional assignment. The directional solution is obtained by the widely used genetic algorithm. A case study based on a real offshore wind farm is established to prove the effectiveness of the proposed methodology. The results show an over one million dollars increase in annual benefit compared with conventional methods.

A Comparative Study on Teaching Methodologies Applied in Engineering and Manufacturing Process Subjects during the COVID-19 Pandemic in 2020 and 2021

Specific disciplines in engineering, such as manufacturing processes, require students in their academic stage to pay special attention, given the possible changes that may affect the acquisition of competencies. In an environment of uncertainty, such as a global pandemic, teaching must adapt without losing the effective delivery of content to students. The health and safety measures applied during the first months of the pandemic led to a different type of teaching to that which had customarily been applied, such as synchronous and asynchronous methodologies defined by the university’s governing bodies, where face-to-face and online methodologies coexisted in the same academic year. All of this avoided interrupting the academic year. This paper studies the results achieved in this uncertain environment, extends them and compares them with the following year, where only the face-to-face methodology was applied to the students enrolled in Manufacturing Processes 2 at the Centro Universitario de Mérida within the Bachelor’s Degree in Design Engineering and New Product Development (Grado en Ingeniería en Diseño y Desarrollo de Nuevos Productos -GIDIDP-). An analysis of variance (ANOVA) was applied to the data obtained to locate the significant differences between the samples taken in the first year with online and face-to-face teaching methodologies and those taken in the second year with an exclusively face-to-face methodology. When comparing the results, maintaining face-to-face teaching proved essential, as it contributes towards achieving better marks or maintaining the level. However, online methodologies also help as an additional tool to acquire other knowledge and specific skills in these technical engineering subjects, specifically those dealing with the manufacturing processes addressed in this study.

High-Accuracy GNSS Positioning of Ocean Vessels for Sea Wave Monitoring

Kim, M. and Bae, T.-S., 2021. High-accuracy GNSS positioning of ocean vessels for sea wave monitoring. In: Lee, J.L.; Suh, K.-S.; Lee, B.; Shin, S., and Lee, J. (eds.), Crisis and Integrated Management for Coastal and Marine Safety. Journal of Coastal Research, Special Issue No. 114, pp. 415–419. Coconut Creek (Florida), ISSN 0749-0208. This study aims to develop a high-precision strategy for the positioning of marine vessels to monitor sea waves. Thus, the total electron content (TEC) in the ionosphere will be accurately corrected in the positioning process. We analyzed various aspects of ionospheric delay using the Global Ionosphere Map (GIM). The results indicated that the ionosphere was affected by the frequencies and long-term changes of the TEC. It is critical to synchronize the correction information and GNSS observation data on ocean vessels. We developed a methodology for the time synchronization of the GIM, specifically for the ocean, on which only a small number of continuously operating reference station (CORS) networks are available. The generated ionosphere model was compared to the GIM with a maximum of 1.6 TEC, which should be verified for a longer period of time.

Legal Discovery in Islamic Perspective

In general, legal discovery refers to conducting legal searches when the statutory regulations are not regulated and are unclear. Legal discovery is not only based on the concept of positive law, but it also refers to Islamic concepts. This aims to find the law on an issue where the regulation is not yet regulated. Thus, inexistence and unclear issues in law become present and apparent. Legal discovery in Islamic concept is known as Ijtihad, an act and an effort to find, understand, and formulate Islamic Shari’ah ruling. Legal discovery in Islam is conducted using several methods including istinbat, interpretation, literal/linguistic, causation (ta’lili), and synchronization methodologies. Other methods of legal discovery are qiyas, istihsan, maslahah mursalah, istishhab, urf, mazhab shahabi which cannot be separated from the main sources of Islamic law, the Qur’an and hadith. Meanwhile, ra'yu and ijtihad are ways of thinking in understanding the Qur’an and hadith. These are to determine a problem where its nash has not been determined. The researchers employed library research in this study. The study examined the documents using secondary data and analyzed it using a qualitative method where the data are described in words, not numbers. In addition, the data collection is based on literature studies taken from books, journals, and internet sources related to legal discovery in the Islamic concept.

Design, Modelling, and Analysis of Novel Solar PV System using MATLAB

In order to meet the world's future energy demand, alternative renewable green energy supplies must be widely promoted. Among all DERs, the most prevalent is Solar PV for a number of important reasons. In this study, the authors analyze several elements of the Single-Phase Solar Photovoltaic Rooftop System with MATLAB. In order to analyze the characteristics of the output current, a new grid synchronization methodology has been devised. For maximum power tracking, the INC control technique has been adopted. The output of the solar DC power system has been synchronized with the grid through hysteresis current loop control. Extensive testing verifies the practicality of the proposed power grid model and promising outcomes and results.