Difficulty Of Synchronization Research Articles

Kepuasan Pengguna Fitur Medis ePuskesmas dengan Model EUCS dan DeLone & McLean di Sumedang

An ePuskesmas is a health information system developed through the collaboration of the Sumedang District Health Office and PT Infokes Indonesia. It offers various features to aid health workers at Puskesmas, notably the medical feature for managing patient data during polyclinic examinations. However, this feature faces issues such as synchronization difficulties with Pcare, slow system responses due to high user traffic, and frequent errors. This study aims to assess user satisfaction with the medical features of ePuskesmas using the End User Computing Satisfaction (EUCS) model and the DeLone and McLean Model. The study involves 93 respondents, including nurses, midwives, and doctors from Sumedang Regency Health Center, selected through purposive sampling. Data analysis is performed using SmartPLS 3.2.9 with PLS-SEM. The results indicate overall user satisfaction with the medical features of ePuskesmas. Out of 8 hypotheses, 3 are accepted, and 5 are rejected. Key factors influencing user satisfaction include Accuracy, Ease of Use, and Information Quality. This research is important to find out whether the system developed by related parties is in accordance or not with the end user

Color image encryption scheme for distributed architecture with SCFP chaotic map

Image protection mechanism in distributed cloud network is an essential component of information security field. In this paper, a novel one-dimensional sine-cosine fractional power chaotic map (SCFP) is proposed. Results of various dynamical system tests illustrate that SCFP exhibits superior chaotic behavior over its infinite positive real parameter range, whose complexity and unpredictability can guarantee the strength of image cryptosystem. Furthermore, a color image encryption scheme tailored for distributed architecture is devised. Firstly, a hybrid cryptographic mechanism is designed to perform diffusion and confusion encryption for image data and ECC public key encryption for intermediate keys. Secondly, the diffusion structure elevates processing units to row-column level, and the diffusion order is dictated by a pseudo-random sequence generated by SCFP. Thirdly, the confusion structure extends the unbiased and efficient Fisher-Yates algorithm into a 2D space, and adopts a design of dual plaintext-related key. Lastly, three techniques namely QOI lossless compression, DE information embedding and threshold secret sharing are integrated to resolve issues of data volume inflation, key synchronization difficulty and poor fault tolerance. Simulation experiments conducted on multiple color images demonstrate that the proposed scheme offers significant ciphertext randomness, sufficiently large key space and strong key sensitivity, which can ensure the integrity of image data and resist various typical cryptographic attacks, and outperforms existing schemes oriented to centralized architecture in terms of security and efficiency.

Five-axis toolpath interpolation method with kinematic corner smoothing and time synchronization

osMost toolpaths of high speed five-axis machining are composed of discrete tool positions and tool orientation vectors. Thus, toolpath smoothing is essential for increasing the machining efficiency and quality. Traditional smoothing methods face the difficulties of synchronization, computational load, feedrate fluctuation and overshoot due to the inefficient procedure of geometric smoothing followed by interpolation. To break these bottlenecks, a novel interpolation method for five-axis toolpaths with kinematic corner smoothing and time synchronization is proposed in this paper. Rather than smoothing the toolpaths geometrically, the translational velocity of tool position and the rotary angular velocity of tool orientation are directly scheduled in the workpiece coordinate system (WCS). Additionally, algorithms of time synchronization and interpolation are proposed to synchronize translation with rotation, and calculate interpolated tool positions and orientations efficiently. Simulation and experimental studies are conducted to validate the effectiveness and feasibility of the proposed method. Compared with a geometric corner smoothing method, the proposed method generates interpolated toolpaths perfectly respecting the geometric and kinematic constraints. Both the tangential and the axial kinematic profiles obtained by the proposed method are smooth and free of jitters at block junctions. Furthermore, the proposed method improves the machined surface quality, and reduces the computational time by over 50 % without solving optimization problems or scheduling recursively.

Research on railway BIM platform framework based on homemade graphics engine

At present, BIM platforms rely on foreign software. Homemade software and industry applications are mostly secondary developments, which present stranglehold problems caused by interruptions to the software supply. To solve the problem, key technical research on the 3D integrated design of railway engineering was stuedied based on homemade graphics engines to propose an innovative railway BIM platform framework. The entire process was completed from the top-level design to the engineering verification of the platform. The co-designed mechanism of a "center model and link" hybrid mode was constructed, which solved the difficulties of data management and increment synchronization at a large scale, achieving teamwork among surveying and mapping, alignments, and bridges. The results of this study could provide strong support for the development of BIM software for a whole railway and all majors.

Synchronization techniques for underwater acoustic communications

SummaryUnderwater acoustic channel is a challenging medium for communication due to the presence of significant multipath, high noise, frequency‐dependent propagation loss, and high and non‐uniform Doppler spread. Doppler shift is non‐negligible in underwater communication due to the low velocity of underwater signals. Synchronization and Doppler estimation are important requirements for achieving good performance in this channel. Synchronization algorithms that give good performance in radio communication do not work well in underwater communication. Hence, this area has received a lot of attention from researchers. This paper surveys important works in the area. The techniques proposed in the literature for frame synchronization, frequency and phase synchronization, and timing synchronization in single carrier communications are reviewed here. The synchronization techniques proposed for OFDM, MIMO OFDM, and spread spectrum communication are also surveyed. Doppler estimation methods proposed in the literature are also reviewed. It is found that most of the recent works in underwater acoustic communication focus on OFDM synchronization. Deep learning‐based methods proposed in the literature are also reviewed. Key open problems and areas that require future research attention in the field of synchronization and Doppler estimation in underwater communications are highlighted in this paper. The area needing most attention of underwater communication researchers was found to be MIMO OFDM due to the difficulty in synchronization in such systems while used in underwater communication. Reducing the computational complexity of the algorithms used is also important for future work. Schemes that work with Doppler due to relative velocity over 10 m/s also need to be developed.

Poor synchronization yet adequate tempo-keeping in adults with autism.

Sensorimotor synchronization to external events is fundamental to social interactions. Adults with autism spectrum condition (ASC) have difficulty with synchronization, manifested in both social and non-social situations, such as paced finger-tapping tasks, where participants synchronize their taps to metronome beats. What limits ASC's synchronization is a matter of debate, especially whether it stems from reduced online correction of synchronization error (the "slow update" account) or from noisy internal representations (the "elevated internal noise" account). To test these opposing theories, we administered a synchronization-continuation tapping task, with and without tempo changes. Participants were asked to synchronize with the metronome and continue the tempo when it stopped. Since continuation is based only on internal representations, the slow update hypothesis predicts no difficulty, whereas the elevated noise hypothesis predicts similar or enhanced difficulties. Additionally, tempo changes were introduced, to assess whether adequate updating of internal representations to external changes is possible when given a longer temporal window for updating. We found that the ability to keep the metronome's tempo after it stopped did not differ between ASC and typically developing (TD) individuals. Importantly, when given a longer period to adapt to external changes, keeping a modified tempo was also similar in ASC. These results suggest that synchronization difficulties in ASC stem from slow update rather than elevated internal noise.

Review of trans-Mediterranean power grid interconnection: A regional roadmap towards energy sector decarbonization

Climate change is becoming an important issue in all fields of infrastructure development. Electricity plays a core role in the decarbonized energy system’s path to a regional zero-emission pattern. A well-built trans-Mediterranean backbone grid can hedge the profound evolution of regional power generation, transmission, and consumption. To date, only Turkey and the Maghreb countries (i.e., Morocco, Algeria, and Tunisia) are connected with the Continental European Synchronous Area. Other south- and east-shore countries have insufficient interconnection infrastructures and synchronization difficulties that have proven to be major hurdles to the implementation of large-scale solar and wind projects and achievement of climate goals. This study analyzes the current trans-boundary grid interconnections and power and carbon emission portfolios in the Mediterranean region. To align with the recently launched new climate target ‘Fit for 55’ program and the accelerated large-scale renewables target, a holistic review of projected trans-Mediterranean grids and their market, technical, and financial obstacles of implementation was conducted. For south- and east-shore countries, major legal and regulatory barriers encompassing non-liberalized market structure, regulation gaps of taxation and transmission tariffs, and the private sector’s access rights need to be removed. Enhancement of domestic grids, substations, and harmonized grid codes and frequency, voltage, and communication technology standards among all trans- Mediterranean countries are physical prerequisites for implementing the Trans-Mediterranean Electricity Market. In addition, the mobilization of capital instruments along with private and international investments is indispensable for the realization of supranational transmission projects. As the final section of the decarbonization roadmap, the development of electric appliances, equipment, and vehicles with higher efficiency is inevitable in the decarbonized building, transportation, and industry sectors.

Asynchronous Multi-User Detection for Code-Domain NOMA: Expectation Propagation Over 3D Factor-Graph

Code-domain non-orthogonal multiple access (NOMA) is a promising technology to achieve ubiquitous massive connections for 5G and beyond. In application scenarios with high channel dynamics or simplified scheduling procedures, multi-user signals face the difficulty of accurate synchronization. The resulted asynchronous inter-user interference (IUI) is too complex to be modeled or alleviated by conventional multi-user detection algorithms. To effectively characterize the asynchronous IUI for code-domain NOMA, this paper constructs a three-dimensional (3D) factor-graph by introducing time delay as an additional dimension and develops the corresponding message passing mechanisms. Then, a novel 3D-expectation propagation algorithm (3D-EPA) is proposed for low-complexity asynchronous multi-user detection. The proposed 3D-EPA iterates between per-user estimation, which projects the asynchronous interference via Gaussian approximation, and inter-user message passing, which propagates the previous estimates among the users to refine the approximation. We also extend the 3D-EPA to multi-antenna scenarios and analyze its state evolution. Simulation results show that the proposed asynchronous NOMA system with 3D-EPA even outperforms its synchronous counterpart, especially under high overloadings.

Spatio-temporal coupling controlled laser for electron acceleration

Limited by the difficulty in acceleration synchronization, it has been a long-term challenge for on-chip dielectric laser-based accelerators to bridge the gap between non-relativistic and relativistic regimes. Here, we propose a laser-based accelerators based on a spatio-temporal coupling controlled laser pulse, which enables the acceleration of a non-relativistic electron to a sub-MeV level in a single acceleration structure (chirped spatial grating). It provides high precision temporal and spatial tuning of the driving laser via dispersion manipulation, leading to a synchronous acceleration of the velocity increasing electrons over a large energy range. Additionally, the spatio-temporal coupling scheme is a general method and can be extended to driving fields of other wavelengths such as terahertz pulses. Our results bring possibilities to MeV-scale portable electron sources and table-top acceleration experiments.

O-205 Application of a single “Universal warming protocol” for vitrified donor oocytes: A prospective, multicenter study

Abstract Study question Is it possible to use different commercial thawing kits with donor oocytes that have been vitrified with a Kitazato vitrification kit? Summary answer The Omni thawing kit showed higher survival rates of donor oocytes. However, fertilization, blastulation, and chemical pregnancy rates were similar in all three thawing kits. What is known already Vitrification is the best method for cryopreserving metaphase II (M2) oocytes and blastocysts. Oocyte vitrification and subsequent thawing is performed with the use of different commercial kits. Currently, the thawing kit usually corresponds to the same provider as the vitrification kit used. However, this may create issues when using cryopreserved oocytes among different clinics with different vitrification kits and, furthermore, not all lab professionals are accustomed to using other commercial kits. Using a “single warming protocol” would provide a solution to these drawbacks and would improve the compatibility of exchanging gametes and embryos among collaborating centers. Study design, size, duration This is a longitudinal, comparative and prospective study conducted between January 2017 and December 2020 at four different IVF private centers. Overall, we vitrified a total number of oocytes (n = 2172) with a single Kitazato commercial vitrification kit at a Spanish Egg Bank, and three independent IVF centers used different thawing kits (Kitazato, Irvine or Omni) as a warming protocol. Participants/materials, setting, methods The study included oocytes from altruistic anonymous egg donors aged 18-35 years, subject to the rigorous standards to become an oocyte donor. The primary outcome was survival and fertilization rate; secondary outcomes included blastulation rate, and chemical pregnancy rate. Main results and the role of chance A total of 2172 M2 oocytes were retrieved and subsequently vitrified using the Kitazato protocol and the Cryotop device. All vitrified donor M2 oocytes were thawed at independent assisted reproduction centers using the following thawing kits: Omni Vitrolife (n = 655), Kitazato (n = 1021), and Irvine (n = 496). Oocytes thawed using the Omni kit had a 94% (617/655) survival rate and a 73% fertilization rate. Kitazato thawing kits had an 86% (877/1021) survival rate and a 77% fertilization rate. Lastly, Irvine thawing kits had an 85% (423/496) survival rate and a 74% fertilization rate. Survival rate results were statistically significant among different thawing kits (P-Value = <0.01). Fertilization rates were not statistically significant. Blastulation rates with Omni, Kitazato and Irvine thawing kits were 57%, 52%, and 58%, respectively (Not statistically significant). Lastly, chemical pregnancy (HCG-Beta positive) rates with Omni, Kitazato and Irvine thawing kits, results were 65%, 54%, and 76%, respectively (Not statistically significant). Limitations, reasons for caution The study was carried out in centers with long experience collaborating together, but many different professionals intervened in the process, without the same conditions in all labs. Wider implications of the findings With increasing requirements for cryopreserved oocytes due to the difficulties of donor-recipient synchronization, popularization of treatments from abroad, and the need to import or send donor oocytes for recipient phenotypes, it has become of paramount importance to use a single universal warming protocol irrespective of cryopreservation kits. Trial registration number NOT APPLICABBLE

Beat Synchronization and Reading: The Feasibility of Music and Video Game Trainings

Abstract The prevalence of reading disabilities ranges from 5% to 12%, making it important to support reading programs. More specifically, children with reading disabilities show difficulties in beat synchronization that requires fine audio-motor synchrony. This synchrony, which demonstrates temporal processing skills, is linked to reading development. The purpose of the present study was to establish the feasibility of 2 music training programs for reading through practicing beat synchronization and to explore the preliminary efficacy of these programs for third graders identified as having reading challenges. Two participants attended the rhythmic music exercise group where they performed musical tasks set to a metronome beat. Two other participants attended the video game playing group where they played Donkey Konga. Each group attended a 30-minute session twice a week for 4 weeks. The Gray Oral Reading Test Fifth Edition (GORT-5) was used to assess reading ability. Selected subtests from the Comprehensive Test of Phonological Awareness Second Edition (CTOPP-2) were used to assess phonological processing. Feasibility data indicated that both programs were successfully implemented and well received by the participants. While preliminary-efficacy analysis demonstrated positive trends in the reading and phonological awareness tests for the rhythmic music exercise group and mixed results for the video game playing group, a large, controlled pilot study is needed to determine the effects of these training programs. Music therapists may potentially apply the proposed rhythmic music exercises to address reading-related goals.

Biomechanics of healthy subjects during exercise on a simulated vibration isolation and stabilization system

With long-term space flights being planned for the Moon and Mars, proper countermeasures must be taken to facilitate human health in microgravity environments. Exercise is a vital countermeasure used to prevent bone and muscle loss, among other health interests. Future exploration missions encourage creating an exercise device that is both compact and can be used to properly execute exercise by the astronauts. Current design considerations include interfacing an exercise device with a vibration isolation and stabilization (VIS) system, which is necessary for protecting the spacecraft and sensitive experiments from harmful vibrations developed during repetitive exercise. This human factor study assesses the feasibility of a VIS system exercise device by using the Computer Assistive Rehabilitation Environment (CAREN) to simulate characteristics of the system. The CAREN includes a 6 degree of freedom (DOF) platform, force plates and a motion capture system. An algorithm was developed using the D-Flow software to move the platform in 1 and 2 DOF sinusoidal responses. Multiple sinusoidal frequencies for platform motion during subject exercise were evaluated. Four subjects completed squat and row exercises on the CAREN while their motion was recorded. Kinematic and kinetic data were collected from each subject. Trials were executed with 1-2 DOF motion in heave and pitch. Results conclude that subjects completed exercises with adequate range of motion (ROM) and ground reaction forces (GRF) during each trial. Certain environments, such as movement at a slower frequency (0.10 Hz) and movement of heave and pitch at differing frequencies, caused loss of balance indicated by grabbing of the handrail in some subjects and difficulty in synchronization between the subjects and the platform. This indicates that VIS system design should focus on frequency of movements centering around subjects’ natural exercise frequencies if possible. This study serves as a proof of concept for using CAREN and programming tool D-Flow to simulate platform movement on VIS system design. Further experimentation will test more detailed designs, including active and passive systems that will move based on real-time subject data.

A Comprehensive Comparison and Analysis of Several Intensity Modulations Based on the Underwater Photon-Counting Communication System

Underwater wireless optical communication is facing absorption, scattering problems, which, in principle, can be greatly resolved by underwater photon-counting communication (UPCC) technology that exhibits high-sensitivity communication characteristics in long-range underwater wireless optical communication. Recent studies on UPCC are mainly focused on a single intensity modulation such as on–off keying (OOK) and pulse position modulation (PPM) technologies, and the comprehensive analysis of communication performance combing OOK modulation and digital pulse modulations remains a lack. To this, by using a UPCC system based on a single-photon avalanche diode, we reveal the communication performances of OOK, PPM, differential pulse interval modulation (DPIM), differential pulse position modulation (DPPM), and dual-header pulse interval modulation, and find that (1) the PPM has the longest transmission distance at the same bit error ratio when M > 2, but the lowest communication rate under identical modulation bandwidth and average transmit power; and (2) the DPPM and DPIM perform the optimum communication performance at the fixed communication rate when M = 8. We thus conclude that the DPPM and DPIM have advantages of low modulation bandwidth and long time slot time compared with PPM, indicating the significance of reducing the difficulty of signal synchronization and the complexity of the underwater photon-counting system accordingly.

Stability analysis and synchronization of incommensurate fractional-order neural netwroks

This paper develops a theoretical framework for analyzing the stability of nonlinear incommensurate fractional- order neural networks. A necessary theorem for asymptotical stability is established using the characteristic equation for a nonlinear fractional-order system, and how to employ this theorem in stabilization is also presented. With the suitable control, the difficulties of stabilization and synchronization of fractional-order chaotic incommensurate fractional-order neural networks may be readily overcome. Two numerical examples have been shown to demonstrate how the established theory may be used to investigate stability and construct stabilization controllers.

Asymptotic and finite-time cluster synchronization of neural networks via two different controllers

<p style='text-indent:20px;'>In this paper, by using a pinning impulse controller and a hybrid controller respectively, the research difficulties of asymptotic synchronization and finite time cluster synchronization of time-varying delayed neural networks are studied. On the ground of Lyapunov stability theorem and Lyapunov-Razumikhin method, a novel sufficient criterion on asymptotic cluster synchronization of time-varying delayed neural networks is obtained. Utilizing Finite time stability theorem and hybrid control technology, a sufficient criterion on finite-time cluster synchronization is also obtained. In order to deal with time-varying delay and save control cost, pinning pulse control is introduced to promote the realization of asymptotic cluster synchronization. Following the idea of pinning control scheme, we design a progressive hybrid control to promote the realization of finite time cluster synchronization. Finally, an example is given to illustrate the theoretical results.</p>

Mathematical models of CBSC over wireless channels and their analysis by using the LeNN-WOA-NM algorithm

In recent studies, several chaos-based secure communication (CBSC) systems are developed and are assumed to be effective and promising tools for balancing communications in wireless applications. The reliability of a wireless communication system is dependent on the synchronization between receiving and transmitting nodes. Therefore, it is crucial to analyze the mathematical models for different enhancements through CBSC and avoid the difficulty in synchronization. We have designed a novel computational paradigm that uses weighted Legendre polynomials to construct series solutions for mathematical models of the Lorenz Chaotic Attractor (LCA) and Double Scroll Attractor (DSA) (with filter and without filter) by using Chua’s circuits. We design fitness functions for each system of differential equations. Two optimization techniques, the Whale Optimization Algorithm (WOA) and the Nelder–Mead (NM) algorithm are adopted to optimize the objective functions and calculate the best set of unknown weights. We name our soft computing paradigm, the LeNN-WOA-NM algorithm. We have compared our results with state-of-the-art, and we establish that the LeNN-WOA-NM algorithm is fast, accurate, and reliable. We present graphical and statistical analysis to further elaborate on the performance of our algorithm.

Towards a Comprehensive Account of Rhythm Processing Issues in Developmental Dyslexia.

Developmental dyslexia is typically defined as a difficulty with an individual’s command of written language, arising from deficits in phonological awareness. However, motor entrainment difficulties in non-linguistic synchronization and time-keeping tasks have also been reported. Such findings gave rise to proposals of an underlying rhythm processing deficit in dyslexia, even though to date, evidence for impaired motor entrainment with the rhythm of natural speech is rather scarce, and the role of speech rhythm in phonological awareness is unclear. The present study aimed to fill these gaps. Dyslexic adults and age-matched control participants with variable levels of previous music training completed a series of experimental tasks assessing phoneme processing, rhythm perception, and motor entrainment abilities. In a rhythm entrainment task, participants tapped along to the perceived beat of natural spoken sentences. In a phoneme processing task, participants monitored for sonorant and obstruent phonemes embedded in nonsense strings. Individual sensorimotor skills were assessed using a number of screening tests. The results lacked evidence for a motor impairment or a general motor entrainment difficulty in dyslexia, at least among adult participants of the study. Instead, the results showed that the participants’ performance in the phonemic task was predictive of their performance in the rhythmic task, but not vice versa, suggesting that atypical rhythm processing in dyslexia may be the consequence, but not the cause, of dyslexic difficulties with phoneme-level encoding. No evidence for a deficit in the entrainment to the syllable rate in dyslexic adults was found. Rather, metrically weak syllables were significantly less often at the center of rhythmic attention in dyslexic adults as compared to neurotypical controls, with an increased tendency in musically trained participants. This finding could not be explained by an auditory deficit in the processing of acoustic-prosodic cues to the rhythm structure, but it is likely to be related to the well-documented auditory short-term memory issue in dyslexia.

Robust frame synchronization for free-space continuous-variable quantum key distribution.

Free-space continuous-variable quantum key distribution (CV-QKD) is an important technology that enables all-day quantum key distribution. Precise frame synchronization is a prerequisite for establishing a correlation between legitimate users of CV-QKD. In free-space CV-QKD, channel transmittance fluctuation caused by atmospheric turbulence increases the difficulty of synchronization. Also, as the channel transmittance is monitored in many reported experiments, the transmittance data also needs to be synchronized. We propose a novel method to solve the above problems by inserting two kinds of synchronization frames, i.e., data synchronization frames and transmittance synchronization frames. The performance of the proposed method is analyzed and Monte Carlo simulation is conducted to test its performance. The results demonstrate the feasibility and efficiency of this method. The proposed method paves the way for the realization of free-space CV-QKD.

Synchronization on Lur’e Cluster Networks With Proportional Delay: Impulsive Effects Method

This article is devoted to study the cluster synchronization for a kind of complex dynamical networks consisting of nonidentical nonlinear Lur'e systems. Different from general time delays, a proportional delay is taken into consideration in this article, which is a kind of unbounded time-varying delays and thus largely increases the difficulty in network synchronization. In consideration of the topology structures of the Lur'e networks, an effective impulsive pinning controller is proposed, which will be placed on the Lur'e systems having directed paths with those in the other clusters. Considering different functional roles that the impulsive effects play, sufficient criteria for the cluster synchronization of the nonidentically coupled Lur'e dynamical networks are obtained by applying the proportionally delayed impulsive comparison principle, the concept of average impulsive interval, and the extended parameters variation formula. Simultaneously, the exponential convergence rates are successfully estimated with respect to different functions of the impulsive effects. In the end of this article, three numerical simulations are proposed to denote the effectiveness of the control protocols and the theoretical results.

Grid synchronization of variable speed pump-turbine units in turbine mode

The S-shaped characteristics of the pump-turbine may cause instability and thus leads to difficulties in grid synchronization. This paper develops a complete model for a pumped storage power plant and studies the start-up and grid synchronization procedure of two 300 MW variable speed units at no load in turbine mode. Based on the grid-voltage-oriented vector control method, the stator voltage of the doubly-fed induction machine is controlled to meet the grid connection requirements. Compared with the fixed speed units, the simulation results show that for a pump-turbine with typical S-shaped characteristics, the fixed speed unit cannot meet the grid connection requirements due to the unstable unit speed. Whereas, the variable speed unit can quickly reach synchronization with the grid voltage. For a pump-turbine without typical S-shaped characteristics, the synchronous unit can meet the grid connection requirements, but it takes a longer time and the stator voltage is not stable enough, while the variable speed unit is 11 times faster and more stable. The effects of PI parameters on the synchronization process of a variable speed unit are also studied. The results show that with suitable PI control parameters, the synchronization process can be accelerated without large overshoot of the rotor power.