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A new architectural approach to real-time embedded programming is described. A bare-metal program is written in C/C++ and combines event-driven technique with concurrency based on co-routines. Events are processed by soft real-time core at the priority level of software generated interrupts. Event is first posted to input queue of the core and then processed by invocation of its event handler. A special case of event is co-routine, its resumable function being a co-routine event handler. The co-routine that either yielded or needs to be resumed is queued for event processing once again. As a result, it is processed multiple times until execution of resumable function comes to the end of its operator sequence. Different levels of processing priority may be assigned to an event. Soft real-time core could be further expanded to run on symmetrical multiprocessor hardware. A combination of co-routines and basic events could easily be used in fork/join model. Concurrency constructs resemble those of Go and occam languages. Virtually all classic types of synchronization primitives could be implemented. The new approach was implemented for various ARM and Blackfin processors in C++ language as portable DORSECC library. This library was further used to program real-time embedded systems for mass-produced banknote sorting machines. One type of systems was used to recognize and validate banknote images by the method of cascade of one-class classifiers. The other system worked as a motion controller and used finite automata to control sensors and actuators. The total number of systems in operation is currently over 20000. The event and co-routine core in these systems provides average event processing time in the range of dozens of microseconds with sub-microsecond overhead time per each event. [ABSTRACT FROM AUTHOR]

The four-axis variable trajectory equal-thickness screen (FAVTETS) achieves equal-thickness screening by appropriate excitation force generated by four eccentric rotors in synchronized motion. The forced synchronization exciter is characterized by an unsatisfactory synchronization effect due to the wear of transmission parts. Hence, in this paper, the four-axis controlled synchronization of FAVTETS is investigated, and an intelligent control system is proposed. Firstly, research is conducted on the variable trajectory characteristics of FAVTETS. Next, the sliding mode, fuzzy, and PID controllers are designed and compared to obtain an ideal control effect. Moreover, the influence of torsional stiffness of flexible coupling on control accuracy is considered. The results show that the sliding mode controller has a good control effect. Based on the aforementioned, the simulation model of a four-axis controlled synchronization structure is established via MATLAB/Simulink. Finally, Labview is employed to design the four-axis controlled synchronization software system. Then, the physical experiment is carried out. The four-axis controlled synchronization and vibration trajectory measurement results verify the effectiveness and robustness of the intelligent control system. [ABSTRACT FROM AUTHOR]

Cloud computing and edge computing brought more software, which also brought a new danger of malicious software attacks. Data synchronization mechanisms of software can further help reverse data modifications. Based on the mechanisms, attackers can cover themselves behind the network and modify data undetected. Related knowledge of software reverse engineering can be organized as rules to accelerate the attacks, when attackers intrude cloud server to access the source or binary codes. Therefore, we proposed a novel method to resist this kind of reverse engineering by breaking these rules. Our method is based on software obfuscations and encryptions to enhance the security of distributed software and cloud services in the 5G era. Our method is capable of (1) replacing the original assembly codes of the protected programwith equivalent assembly instructions in an iteration way, (2) obfuscating the control flow of the protected program to confuse attackers meanwhile keeps the program producing the same outputs, (3) encrypting data to confuse attackers. In addition, the approach can periodically and automatically modify the protected software binary codes, and the binary codes of the protected software are encrypted to resist static analysis and dynamic analysis. Furthermore, a simplified virtual machine is implemented to make the protected codes unreadable to attackers. Cloud game is one of the specific scenarios which needs low latency and strong data consistency. Cheat engine, Ollydbg, and Interactive Disassembler Professional (IDA) are used prevalently for games. Our improved methods can protect the software from the most vulnerable aspects. The improved dynamic code swapping and the simplified virtual machine technologies for cloud games are the main innovations. We inductively learned that our methods have been working well according to the security mechanisms and time complexity analysis. Experiments show that hidden dangers can be eliminated with efficient methods: Execution time and file sizes of the target codes can be multiple times than that of the original program codes which depend on specific program functions. [ABSTRACT FROM AUTHOR]

Background: Lung perfusion using 99mTc-macroaggregated albumin single-photon emission computed tomography (SPECT) and lung computed tomography (CT) is a useful modality for identifying patients with pulmonary artery embolism. However, conformity between SPECT and CT at the bottom of the lung is generally low. This study aims to investigate the progression of conformity between lung perfusion SPECT and lung CT using a breathing synchronization software. Methods: Among 95 consecutive patients who underwent lung perfusion SPECT and lung CT within 14 days because of suspected pulmonary embolism between June 2019 and August 2020 in department of cardiovascular medicine, we identified 28 patients (73 ± 10 years) who had normal pulmonary artery on contrast lung CT. We compared lung volumes calculated using lung perfusion SPECT and lung CT as gold standard. Visual conformity between lung SPECT and lung CT was scored 0–4 (0: 0–25%, 1: 25–50%, 2: 50–75%, 3: 75–90%, 4: > 90%) by two specialists in nuclear medicine and assessed. Results: The lung volume calculated from lung CT was 3749 ± 788 ml. The lung volume calculated from lung perfusion SPECT without using the breathing synchronization software was 3091 ± 610 ml. There was a significant difference between the lung volume calculated from CT and SPECT without using the breathing synchronization software (P < 0.01). The lung volume calculated from lung perfusion SPECT using the breathing synchronization software was 3435 ± 686 ml, and there was no significant difference between the lung volume calculated from CT and SPECT using the breathing synchronization software. The visual score improved with the use of breathing synchronization software (without software; 1.9 ± 0.6 vs. with software; 3.4 ± 0.7, P < 0.001). Conclusion: This study demonstrated that the breathing synchronization software could improve conformity between lung perfusion SPECT and lung CT. [ABSTRACT FROM AUTHOR]

This paper reveals the hidden dangers of reverse data modifications on distributed software with network synchronization, during the era of 5G, which may occur in more important domains, such as telemedicine and automatic driving. We used pseudo-codes to formally elaborate the distributed software architectures and design patterns. It is necessary to deal with three challenges for the modification of binary code and data in the distributed software architectures: (1) the base virtual addresses of software objects are changed frequently for safety; (2) prior knowledge of the reverse is not considered; (3) system memory values of some target objects are changed with extreme speed. For this purpose, a novel reverse modification method for binary code and data is proposed. According to the knowledge-based rules, our method can manipulate physical data, sight data, animation data, etc., while the game synchronization mechanism cannot detect the changes. The implementation details of our method are presented using high-level programming languages (C++) and low-level programming languages (assembly), based on multiple snippets, so that readers can understand both the overall distributed software developments and the corresponding reverse processes. In particular, two network games are used for the demonstrations in this paper. The demonstration results show that our proposed methodology is efficient (as proved by formulas and practices) to manipulate the codes and data of distributed software using a synchronization mechanism. [ABSTRACT FROM AUTHOR]

Automatic operations of multi-functional and time-lapse live-cell imaging are necessary for the biomedical science community to study active, multi-faceted, and long-term biological phenomena. To achieve automatic control, most existing solutions often require the purchase of extra software programs and hardware that rely on the manufacturers' own specifications. However, these software programs are usually non-user-programmable and unaffordable for many laboratories. To address this unmet need, we have developed a novel open-source software program, titled Automatic Multi-functional Integration Program (AMFIP), as a new Java-based and hardware-independent system that provides proven advantages over existing alternatives to the scientific community. Without extra hardware, AMFIP enables the functional synchronization of the μManager software platform, the Nikon NIS-Elements platform, and other 3rd party software to achieve automatic operations of most commercially available microscopy systems, including but not limited to those from Nikon. AMFIP provides a user-friendly and programmable graphical user interface (GUI), opening the door to expanding the customizability for myriad hardware and software systems according to user-specific experimental requirements and environments. To validate the intended purposes of developing AMFIP, we applied it to elucidate the question whether single cells, prior to their full spreading, can sense and respond to a soft solid substrate, and if so, how does the interaction depend on the cell spreading time and the stiffness of the substrate. Using a CRISPR/Cas9-engineered human epithelial Beas2B (B2B) cell line that expresses mNeonGreen2-tagged mechanosensitive Yes-associated protein (YAP), we show that single B2B cells develop distinct substrate-stiffness-dependent YAP expressions within 10 hours at most on the substrate, suggesting that cells are able to sense, distinguish, and respond to mechanical cues prior to the establishment of full cell spreading. In summary, AMFIP provides a reliable, open-source, and cost-free solution that has the validated long-term utility to satisfy the need of automatic imaging operations in the scientific community. [ABSTRACT FROM AUTHOR]

We report a synchronized time tagger based on a field-programmable-gate-array chip for one- or two-dimensional quantum experiments that require precise single-photon detections. The time tagger has a 9.2 ps single-shot root-mean-square precision and is equipped with a 1 GB dynamic memory for data storage. Because the relationship between the control parameter and acquired data is guaranteed by using hardware synchronization, the experiment can be performed much faster than conventional schemes that are based on software synchronization. With this technique, an improvement of up to 61.3% in efficiency is observed in a typical nitrogen-vacancy center quantum experiment. We further show advanced optical features of the center using the detected high-resolution photon-arrival information and provide detailed electrical benchmarking of the device. This technique could be easily extended to other quantum control systems. [ABSTRACT FROM AUTHOR]

Enabling technologies that drive Industry 4.0 and smart factories are pushing in new equipment and system development also to prevent human workers from repetitive and non-ergonomic tasks inside manufacturing plants. One of these tasks is the order-picking which consists in collecting parts from the warehouse and distributing them among the workstations and vice-versa. That task can be completely performed by a Mobile Manipulator that is composed by an industrial manipulator assembled on a Mobile Robot. Although the Mobile Manipulators implementation brings advantages to industrial applications, they are still not widely used due to the lack of dedicated standards on control and safety. Furthermore, there are few integrated solutions and no specific or reference point allowing the safe integration of mobile robots and cobots (already owned by company). This work faces the integration of a generic mobile robot and collaborative robot selected from an identified set of both systems. The paper presents a safe and flexible mechatronic interface developed by using MBSE principles, multi-domain modeling, and adopting preliminary assumptions on the hardware and software synchronization level of both involved systems. The interface enables the re-using of owned robot systems differently from their native tasks. Furthermore, it provides an additional and redundant safety level by enabling power and force limiting both during cobot positioning and control system faulting. [ABSTRACT FROM AUTHOR]

Providing group study rooms is an important service offered by a university library to support learning and collaboration. A good room booking system should be convenient for students to use and would require a minimum involvement of library staff regarding managing bookings and keys. This article studied the implementation of the Juno Secure Room Booking system at the library to replace LibCal, which is a popular room booking system used by a large number of university libraries in North America. This article discussed the advantages that the Juno system has compared to LibCal, the design of an online booking website using the Juno Application Programming Interface (API), and the enhancement the library designed and developed based on student feedback. This article also discussed how the library successfully engaged a college to use this system to manage study rooms for classes and exams. [ABSTRACT FROM AUTHOR]

Humanitarian medical organizations rely on information on and from the ground to evaluate their effectiveness and accountability. Related digitalization efforts within health information systems assume an instrumental rationality in the use of data. However, previous research identified a multitude of factors influencing actual information use for evidence‐based decision‐making for healthcare delivery. This case study, anchored by critical realism philosophy, unpacks these nuances against the backdrop of a globally operating organization (Médecins Sans Frontières). It aims to highlight the contextual conditions and structures that enact the contingent mechanisms at work in project monitoring within humanitarian health management information systems. By applying an affordance‐based causal analysis, three mechanisms are identified: first, an analytics service provides templated analysis modalities resulting in user–producer–provider relationships; second, the rationalization and synchronization of content and software artifacts gives rise to the standardization strategy of flexible generification; third, the study uncovers the potential for increased internal social discourse and advocacy through collaborative and mobile data analysis. This paper proposes that mechanism‐based explanations can be useful for theory‐building in information systems research as well as for providing insights to practitioners in the humanitarian health sector. [ABSTRACT FROM AUTHOR]

The relevance of the work lies in the need to increase the efficiency of computer modeling through the use of progressive hardware and software parallelization and synchronization of calculations on modern computers with multi-core architecture. The purpose of the work is to increase the speed of computational algorithms of Thomas algorithm by using advanced technologies for programming parallel computing. Serial and parallel algorithms for software implementation of Thomas algorithm have been developed; a comparative evaluation of the implementation efficiency (speed of execution) of these algorithms by means of an open standard for parallelizing OpenMP programs for a significant (up to 5×107) SLAE order was performed. The use of progressive programming technologies in the implementation of the indicated methods for solving SLAEs made it possible to increase the computation speed by 1,9-2,9 times. The obtained results correspond with the known literature data. In this work, the time values of the software implementation of sequential and computational algorithms of Thomas algorithm for SLAEs of significant order were obtained for sequentially and parallelized into two streams using OpenMP tools. The expediency of such parallelization for SLAE of the order of more than 2,5×105 is shown. The practical significance of the work lies in the use of the results obtained in the numerical study of stationary and non-stationary, linear and nonlinear processes in mathematical modeling problems, where the multiple solution of a significant order SLAE is the most resource-intensive stage. [ABSTRACT FROM AUTHOR]

The paper presents a proprietary software system for Modelling of Processes for Data Accumulation and Synthesis in Higher Education, which is designed and developed to overcome the lack of tools suitable enough for work-flows manipulation in the field of Higher Education (HE). The system allows modelling processes in the form of "workflows", accumulation, aggregation and synthesis of information e-resources in relevant digital repositories, virtualization of processes, dynamic visualization of processes and/or their elements, integration and synchronization of heterogeneous software systems working with the system. A special focus is set on processes related to Quality Evaluation. [ABSTRACT FROM AUTHOR]

IoT wearable devices that leverage the LPWAN (Low Power Wide Area Network) connectivity, in particular the NB-IoT (Narrow Band IoT) technology, commonly rely on UDP (User Datagram Protocol) packets to communicate with the endpoint to collect data. Its advantage is that of minimal bandwidth usage but its drawback is the lack of acknowledgements by the endpoint. One option is to use TCP (Transmission Control Protocol) or implement a custom acknowledgement protocol at a superior level in the network stack. This paper presents the implementation and testing of a simple and lightweight software synchronization layer on top of the UDP protocol, for the transmission of live EKG signal data, with verification of data integrity and the detection of sampling points loss. [ABSTRACT FROM AUTHOR]

Collaborating industrial robots and Simulation, as virtual modelling and design tool are key elements of Industry 4.0 conception. Nowadays, the application of industrial robots results in significant improvement of efficiency of production lines and the quality of the final products. Construction of productive industrial robots requires applications of Simulation tools and CAD design software. The article presents a real practical example for the simultaneous application of SolidWorks CAD software and MATLAB simulation software. The authors created the models of two different industrial robot arms using SolidWorks software. After it the created models were exported from the SolidWorks software into the MATLAB software in form of URDF and XML file in order to visualize and optimize the trajectory and the behavior of the industrial robot arms more efficiently. The main added value of the study is that the synchronization of two software applications is described in a real case study. Due to the synchronization of two software applications we can control, visualize and optimize the motion of the robot arms more effectively. Consequently, the optimization of operation of industrial robots resulting in productivity improvement and increasing of profitability and competitiveness of production companies. [ABSTRACT FROM AUTHOR]

The latest research in Spain indicates that the most advanced neuromarketing consulting companies in the sector are those that have been able to innovate in the development of their own technologies and methodologies. Despite their reduced volume of business compared to total investment in marketing and market research in our country, there are signs that suggest these companies have great potential to improve this sector, which is still to be explored. For this reason, this research straddling the ethnographic method and the theoretical–descriptive method aims to help us better understand the characteristic features of this sector by actively listening to the professional voices that lead it. Its epistemological value lies in its contribution to understanding the business culture related to the professional development of neuromarketing in our country today. The study shows that the main human resources strategy of neuromarketing consulting companies is based on the creation of multidisciplinary work teams. In addition, most of them develop data analysis software, which they can safeguard under various types of copyright, and on other occasions they manage to patent them, to later apply them to the objectives and purposes of their company. This would also explain the widespread use of certain procedures and resources by the vast majority of the consulting companies investigated. Thus, the trend in the market is the implementation of different synchronization software to the available technological and methodological resources. Others have even gone so far as to create a new technological support to incorporate methodologies already in use. Therefore, this gives them exclusivity in their services and the necessary competitive advantage over their competitors. Among other factors, these inferences about how this sector really works are very likely to be very useful in the academic field, which will constitute a further step in generating critical thinking and in expanding the frontiers of knowledge around this discipline. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to analyze the key factors influencing the synchronization performance of distributed motion control system and to improve the synchronization performance for peripherals control of this system. Design/methodology/approach: This paper deals with the software synchronization problems of distributed motion control system based on real-time Ethernet. First, combined with communication and control tasks, the key factors affecting synchronization performance of system are analyzed. Then, aiming at key factors and considering the synchronization of system bus, protocol conversion and task scheduling, a software synchronization method based on CANopen protocol and real-time Ethernet is proposed. Finally, the feasibility of this method is verified by establishing distributed motion control system and testing the synchronization performance of terminal control signals of slaves. Findings: Based on this method, the results show that the synchronization accuracy for peripherals control of all slaves could be about 100 ns. Practical implications: This research provides high-precision synchronization method, which could lay a foundation for the application of distributed motion control system in the field of assembly automation, such as multi-axis assembly robots control. Originality/value: In distributed motion control system, many factors affect the synchronization performance. At present, there is no synchronization method that could comprehensively consider these factors. This paper not only analyzes the key factors influencing the synchronization performance of system but also proposes a synchronization method. Therefore, the method proposed in this paper has certain theoretical value and engineering significance. [ABSTRACT FROM AUTHOR]

Concurrency bugs widely exist and severely threaten system availability. Techniques that help recover from concurrency-bug failures during production runs are highly desired. This paper proposes BugTM, an approach that applies transactional memory techniques for concurrency-bug recovery in production runs. Requiring no knowledge about where are concurrency bugs, BugTM uses static analysis and code transformation to enable BugTM-transformed software to recover from a concurrency-bug failure by rolling back and re-executing the recent history of a failure thread. BugTM is instantiated as three schemes that have different trade-offs in performance and recovery capability: BugTM$_H$H uses existing hardware transactional memory (HTM) support, BugTM$_S$S leverages software transactional memory techniques, and BugTM$_{\mathrm{HS}}$ HS is a software-hardware hybrid design. BugTM greatly improves the recovery capability of state-of-the-art techniques with low run-time overhead and no changes to OS or hardware, while guarantees not to introduce new bugs. [ABSTRACT FROM AUTHOR]

A plethora of optimized mutex lock algorithms have been designed over the past 25 years to mitigate performance bottlenecks related to critical sections and locks. Unfortunately, there is currently no broad study of the behavior of these optimized lock algorithms on realistic applications that consider different performance metrics, such as energy efficiency and tail latency. In this article, we perform a thorough and practical analysis of synchronization, with the goal of providing software developers with enough information to design fast, scalable, and energy-efficient synchronization in their systems. First, we perform a performance study of 28 state-of-the-art mutex lock algorithms, on 40 applications, on four different multicore machines. We consider not only throughput (traditionally the main performance metric) but also energy efficiency and tail latency, which are becoming increasingly important. Second, we present an in-depth analysis in which we summarize our findings for all the studied applications. In particular, we describe nine different lock-related performance bottlenecks, and we propose six guidelines helping software developers with their choice of a lock algorithm according to the different lock properties and the application characteristics. From our detailed analysis, we make several observations regarding locking algorithms and application behaviors, several of which have not been previously discovered: (i) applications stress not only the lock-unlock interface but also the full locking API (e.g., trylocks, condition variables); (ii) thememory footprint of a lock can directly affect the application performance; (iii) for many applications, the interaction between locks and scheduling is an important application performance factor; (vi) lock tail latencies may or may not affect application tail latency; (v) no single lock is systematically the best; (vi) choosing the best lock is difficult; and (vii) energy efficiency and throughput go hand in hand in the context of lock algorithms. These findings highlight that locking involves more considerations than the simple lock/unlock interface and call for further research on designing low-memory footprint adaptive locks that fully and efficiently support the full lock interface, and consider all performance metrics. [ABSTRACT FROM AUTHOR]

We present Armus, a verification tool for dynamically detecting or avoiding barrier deadlocks. The core design of Armus is based on phasers, a generalisation of barriers that supports split-phase synchronisation, dynamic membership, and optional-waits. This allows Armus to handle the key barrier synchronisation patterns found in modern languages and libraries. We implement Armus for X10 and Java, giving the first sound and complete barrier deadlock verification tools in these settings. Armus introduces a novel event-based graph model of barrier concurrency constraints that distinguishes task-event and event-task dependencies. Decoupling these two kinds of dependencies facilitates the verification of distributed barriers with dynamic membership, a challenging feature of X10. Further, our base graph representation can be dynamically switched between a task-to-task model, Wait-for Graph (WFG), and an event-to-event model, State Graph (SG), to improve the scalability of the analysis. Formally, we show that the verification is sound and complete with respect to the occurrence of deadlock in our core phaser language, and that switching graph representations preserves the soundness and completeness properties. These results are machine checked with the Coq proof assistant. Practically, we evaluate the runtime overhead of our implementations using three benchmark suites in local and distributed scenarios. Regarding deadlock detection, distributed scenarios show negligible overheads and local scenarios show overheads below 1.15×. Deadlock avoidance is more demanding, and highlights the potential gains from dynamic graph selection. In one benchmark scenario, the runtime overheads vary from 1.8× for dynamic selection, 2.6× for SG-static selection, and 5.9× for WFG-static selection. [ABSTRACT FROM AUTHOR]

Forks/join stations are commonly used to model synchronization constraints in queuing networks. This paper presents an exact analysis of a fork/join station with inputs from stations composed of multiple exponential servers. The queue length process at the input buffers is analyzed exactly using the underlying Markov process. The semi-Markov kernel characterizing the departure process is analyzed to derive expressions for the marginal and joint distributions of inter-departure times from the fork/join station. These analyses are used to study the effect of inputs from multiple servers on key performance measures at a fork/join station. Comparison studies show that inputs from multiple servers have a significant effect on performance measures such as throughput, synchronization delays and queue lengths at the individual buffers. These insights are important to obtain better representation of synchronization constraints in closed queuing network models of computer networks, fabrication/assembly systems and material control strategies for manufacturing systems. [ABSTRACT FROM AUTHOR]

Chaining watermark is an effective way to verify the integrity of streaming data in wireless network environment, especially in resource-constrained sensor networks, such as the perception layer of Internet of Things applications. However, in all existing single chaining watermark schemes, how to ensure the synchronization between the data sender and the receiver is still an unsolved problem. Once the synchronization points are attacked by the adversary, existing data integrity authentication schemes are difficult to work properly, and the false negative rate might be up to 50 percent. And the additional fixed group delimiters not only increase the data size, but are also easily detected by adversaries. In this paper, we propose an effective dual-chaining watermark scheme, called DCW, for data integrity protection in smart campus IoT applications. The proposed DCW scheme has the following three characteristics: (1) In order to authenticate the integrity of the data, fragile watermarks are generated and embedded into the data in a chaining way using dynamic grouping; (2) Instead of additional fixed group delimiters, chained watermark delimiters are proposed to synchronize the both transmission sides in case of the synchronization points are tampered; (3) To achieve lossless integrity authentication, a reversible watermarking technique is applied. The experimental results and security analysis can prove that the proposed DCW scheme is able to effectively authenticate the integrity of the data with free distortion at low cost in our smart meteorological Internet of Things system. [ABSTRACT FROM AUTHOR]

• This paper mainly involves three contributions compared to the previous relevant works. • First, an ETCS is adopted to improve the efficiency of data transmission when addressing the synchronization of MJNNs. • Second, the randomly occurring gain variations are fully considered. • Third, by utilizing some novel inequalities with mode-dependent matrices, some easy-to-check synchronization criteria are presented. Abstract This paper concentrates on the passive synchronization issue for Markov jump neural networks subject to randomly occurring gain variations, in which the event-triggered mechanism is employed to save the limited communication resource. Moreover, the gain variations of the controller are considered to occur in a random way, which is modeled by a Bernoulli parameter. The goal is to build a controller which ensures that the synchronization error system is stochastically stable and satisfies a passive property. By utilizing the stochastic analysis theory and convex optimization technique, some results with less conservatism are derived. Ultimately, the effectiveness and validity of the design method are illustrated by a numerical example. [ABSTRACT FROM AUTHOR]

This paper proposes novel randomized gossip-consensus-based sync (RGCS) algorithms to realize efficient time calibration in dynamic wireless sensor networks (WSNs). First, the unreliable links are described by stochastic connections, reflecting the characteristic of changing connectivity gleaned from dynamic WSNs. Secondly, based on the mutual drift estimation, each pair of activated nodes fully adjusts clock rate and offset to achieve network-wide time synchronization by drawing upon the gossip consensus approach. The converge-to-max criterion is introduced to achieve a much faster convergence speed. The theoretical results on the probabilistic synchronization performance of the RGCS are presented. Thirdly, a Revised-RGCS is developed to counteract the negative impact of bounded delays, because the uncertain delays are always present in practice and would lead to a large deterioration of algorithm performances. Finally, extensive simulations are performed on the MATLAB and OMNeT++ platform for performance evaluation. Simulation results demonstrate that the proposed algorithms are not only efficient for synchronization issues required for dynamic topology changes but also give a better performance in terms of converging speed, collision rate, and the robustness of resisting delay, and outperform other existing protocols. [ABSTRACT FROM AUTHOR]

Chaos synchronization of complex network with uncertain topological structure and coupling coefficient is used to study. By designing appropriate kinetic equation of network node, the chaos synchronization of the complex network is achieved. The unknown parameters and transported values of all the kinetic equations are identified simultaneously in the process of synchronization. When sets the parameter CT for a specific value, the transported values of complex network node is the superposition of specific parameter of passed node. Lorenz system is taken for example to demonstrate the effectiveness of the presented method for a complex network of arbitrary topological type, and the dynamics analysis of the Lorenz chaotic system is given, the results we get including the Lyapunov exponents spectrum and its corresponding bifurcation diagram, and its corresponding analysis of SE complexity algorithm and C0 complexity algorithm are analysis briefly. In this paper, 0-1 test is given respectively. Discusses the influence of parameters on the synchronization performance. It is found that the synchronization performance of the complex network is very stable. [ABSTRACT FROM AUTHOR]

Pipelining allows the execution of loop iterations with cross-iteration dependences to overlap in time, provided that the loop body is partitioned into stages such that the data dependences are not violated. Then, the stages are mapped onto threads and communication and synchronization between stages is typically achieved using queues. Pipelining techniques that rely on static scheduling perform poorly for load-imbalanced loops. Moreover, previous research efforts that achieve load-balancing are restricted to work-stealing and imply high overhead for fine-grained loops. In this article, we present URTS, a unified runtime system with compiler support that provides a lightweight dynamic scheduler by combining mapping, communication and synchronization algorithms with a suitable data structure and an efficient ticket mechanism. Particularly, URTS shows that it is possible to combine the efficiency of static scheduling with the load-imbalance tolerance of work-stealing by using a unified design that exploits the properties of a novel data structure. The evaluation on 8- and 32-core machines shows that URTS implies low overhead, of the same order as a static scheduler, for a set of benchmarks chosen from widely-used collections. URTS is a scalable solution that performs efficient dynamic scheduling for fine-grained loops, i.e., a class of interesting loops that is poorly handled by the state-of-the-art due to high overhead. [ABSTRACT FROM AUTHOR]

Highlights • Synchronization in SO(3) and SE(3) is formulated as a low-rank and sparse matrix decomposition problem. • Any low-rank and sparse matrix decomposition algorithm can be used in this framework. • Good trade-off between resistance to outliers and speed. Abstract This paper deals with the synchronization problem, which arises in multiple 3D point-set registration and in structure-from-motion. The problem is formulated as a low-rank and sparse matrix decomposition that caters for missing data, outliers and noise, and it benefits from a wealth of available decomposition algorithms that can be plugged-in. A minimization strategy, dubbed R-GoDec , is also proposed. Experimental results on simulated and real data show that this approach offers a good trade-off between resistance to outliers and speed. [ABSTRACT FROM AUTHOR]

Concurrent software testing is a challenging activity due to factors that are not present in sequential programs, such as communication, synchronization, and non-determinism, and that directly affect the testing process. When we consider multithreaded programs, new challenges for the testing activity are imposed. In the context of structural testing, an important problem raised is how to deal with the coverage of shared variables in order to establish the association between def-use of shared variables. This paper presents results related to the structural testing of multithreaded programs, including testing criteria for coverage testing, a supporting tool, called ValiPthread testing tool and results of an experimental study. This study was conducted to evaluate the cost, effectiveness, and strength of the testing criteria. Also, the study evaluates the contribution of these testing criteria to test specific aspects of multithreaded programs. The experimental results show evidence that the testing criteria present lower cost and higher effectiveness when revealing some kinds of defects, such as deadlock and critical region block. Also, compared to sequential testing criteria, the proposed criteria show that it is important to establish specific coverage testing for multithreaded programs. [ABSTRACT FROM AUTHOR]

Hardware Transaction Memory (HTM) opens a new way to scaling multi-core software. Its main target is to achieve high performance on multi-core systems, and at the same time simplify concurrency control and guarantee correctness. This paper presents the redesign of an existing concurrent hash table using several HTM-based synchronization mechanisms. As compared with a fine-grained lock implementation, HTM-based locking scales well on our testing platform, and its performance is higher when running large-scale workloads. In addition, HTM-based global locking consumes much less memory. In summary, several observations are made in this paper with detailed experimental analysis, which would have important implications for future research of concurrent data structures and HTM. [ABSTRACT FROM AUTHOR]

Heterogeneous systems with CPU and GPGPU sharing the last level cache (LLC) provide viability and flexibility. However, the different programming models lead to conflicting memory layouts, which are required for best performance of different processors. Software converting that directly accesses target layout is subject to sub-optimal localities. Converting in GPGPU shared memory also incurs copying and synchronization overhead. In this paper, we analyze the memory layout requirement and propose to remap the memory layout in the shared LLC. A remap controller in LLC executes a simple program that calculates target requests from an LLC request in the source memory space. The LLC request is thus remapped to the target memory space with the generated requests. Consequently, all processors always access memory in their optimal data layouts. The locality is thus kept through all the private caches, and software remapping overhead is also eliminated. The tiled-matrix multiplication is discussed as a case study and benchmarks from Polybench/GPU and Rodinia are modified to take advantage of the LLC layout remapping. The experiment results show the average benchmark execution time is decreased to 69%. Compared with CPU software layout converting, the CPU time is decreased to 41%–73%. [ABSTRACT FROM AUTHOR]

In the distributed test architecture, the system under test (SUT) interacts with its environment at multiple physically distributed ports and the local testers at these ports do not synchronize their actions. This presents many challenges and, in particular, apparently incorrect behaviors can be the consequence of an erroneous assumption about the exact order in which actions were performed at different ports. In previous work, we defined a conformance relation for the distributed test architecture. Essentially, the SUT is faulty if we observe a trace $\sigma$ such that no admissible reordering of the actions in $\sigma$ could have been produced by the specification. However, this notion can be weak if the compared traces might be too different. This paper introduces conformance relations where, for a given metric, a reordering is only considered if the distance between the two traces is at most a certain bound $k$. We introduce two different metrics and provide algorithms to construct finite automata accepting these close, with respect to each metric, sequences. We also study the computational complexity of the two main problems associated with the new framework: deciding whether a trace is accepted by the new automaton and deciding whether one system conforms to a specification with respect to the new conformance relation. [ABSTRACT FROM AUTHOR]

In this study, we investigate some counterintuitive but frequent performance issues that arise when doing high-speed networking (or I/O in general) with Virtual Machines (VMs). VMs use one or more single-producer/single-consumer systems to exchange I/O data (e.g. network packets) with their hypervisor. We show that when the producer and the consumer process packets at different rates, the high cost required for synchronization (interrupts and 'kicks') may reduce throughput of the system well below the slowest of the two parties; moreover, accelerating the faster party may cause the throughput to decrease. Our work provides a model for throughput, efficiency and latency of producer/consumer systems when notifications or sleeping are used as a synchronization mechanism; identifies different operating regimes depending on the operating parameters; validates the accuracy of our model against a VirtIO-based prototype, taking into account most of the details of real-world deployments; provides practical and robust strategies to maximize throughput and minimize energy while keeping the latency under control, without depending on precise timing measurements nor unreasonable assumptions on the system's behavior. The study is particularly interesting for Network Function Virtualization deployments, where high-rate producer/consumer systems in virtualized environments are the core components. [ABSTRACT FROM AUTHOR]

A delay of less than one millisecond is required by low-latency 5G wireless communication systems for supporting the “tactile” Internet. Hence, conventional initial synchronisation cannot be readily employed because of its potentially excessive delay. In this paper, an extrinsic information transfer (EXIT) chart assisted approach is used for the convergence analysis of $m$-sequences using recursive soft sequence estimation (RSSE) in the context of Nakagami-m fading channels. Explicitly, the novelty of our work is based on employing a new type of EXIT charts operating without using interleavers. This is a challenge, because the original EXIT charts rely on the employment of long, high-delay interleavers for ensuring that the inputs to the decoders become uncorrelated. We then evaluate the performance of various classes of $m$-sequences with the aid of the proposed EXIT charts and demonstrate that the $m$-sequences generated by the lower order polynomials maximize the mutual information more promptly with the aid of our RSSE scheme than those that belong to a higher order polynomial. [ABSTRACT FROM PUBLISHER]

This paper addresses the viability of using Automatic Speech Recognition (ASR) errors as the predictor of difficulties in speech segments, thereby exploiting them to improve Partial and Synchronized Caption (PSC), which we have proposed to train second language (L2) listening skill by encouraging listening over reading. The system uses ASR technology to make word-level text-to-speech synchronization and generates a partial caption. The baseline system determines difficult words based on three features: speech rate, word frequency and specificity. While it encompasses most of the difficult words, it does not cover a wide range of features that hinder L2 listening. Therefore, we propose the use of ASR systems as a model of L2 listeners and hypothesize that ASR errors can predict challenging speech segments for these learners. Among different cases of ASR errors, annotation results suggest the usefulness of four categories of homophones, minimal pairs, negatives, and breached boundaries for L2 listeners. A preliminary experiment with L2 learners focusing on these four categories of the ASR errors revealed that these cases highlight the problematic speech regions for L2 listeners. Based on the findings, the PSC system is enhanced to incorporate these kinds of useful ASR errors. An experiment with L2 learners demonstrated that the enhanced version of PSC is not only preferable, but also more helpful to facilitate the L2 listening process. [ABSTRACT FROM AUTHOR]

Summary: Personal Cloud (PC) storage services such as Dropbox or Google Drive have become increasingly popular in the last few years. Unfortunately, these services are still not secure. Even assuming “perfect” data confidentiality, securely sharing a folder in these services is still an issue, and this without mentioning the fact that the existing sharing mechanisms are typically too coarse‐grained by operating at the folder level. This is insufficient in many real situations where it is more natural to grant or deny access to files based on arbitrary user attributes and selected attributes of the file. In this research, we explore these issues and show that fine‐grained access control with strong privacy guarantees is practical in the PC. To investigate the potential practicality, we took our fully fledged open source implementation of a PC system and extended it to support fine‐grained private data sharing through attribute‐based encryption. The result was the first design and implementation of a file synchronization service, called StackSync, where the user retains complete control over his or her own data when sharing it. Never before, attribute‐based encryption had been implemented and tested on a real PC service. Our results show that StackSync is both secure and efficient for the PC. [ABSTRACT FROM AUTHOR]

In this paper, we propose a skin care management support system that can provide easy intercommunication between patients and medical staff for optimal management of skin treatment and an aid to diagnosis. This system provides self-management and treatment advice for patients from medical staff. Our research is specially focused on the management of conditions such as psoriasis and melanoma. Although there exist systems have been developed for various medical applications, including some that provide self-monitoring via smartphones, the patient participation rate in using these applications has been low after initial use. This is because obtaining useful information regarding the diagnosis and treatment of disease without the support of medical staff is difficult. We propose a skin care management support system with an enhanced interaction method. It leverages a data synchronization mechanism to enable patients and medical staff to view simultaneously. The system environment is based on cloud computing environment, which provides secure communication by using an Advanced Encryption Standard (AES) between patients and medical staff. Finally, we demonstrate the complete skin care management procedure for skin diseases using a smartphone-based portal service. [ABSTRACT FROM AUTHOR]

The authors investigate pinning synchronisation for two spatial diffusion coupled reaction-diffusion neural networks under undirected and directed topologies. Combined with stability theory, some inequalities and Lyapunov functional method, several sufficient conditions are derived to assure the synchronisation of the considered networks by designing appropriate pinning controllers. It should be pointed out that a new type of spatial diffusion feedback pinning controller is designed in this paper. The correctness of the obtained results is confirmed by two simulation examples. [ABSTRACT FROM AUTHOR]

Cluster analysis is often regarded as a pretreatment step in many data mining applications. It is an unsupervised learning method that tries to find some distributions and patterns in unlabeled data sets. Clustering algorithms have been studied for decades, but we think that none of them is all purpose. This paper presents three fast synchronization clustering algorithms based on spatial index structures, which are three improved versions of SynC algorithm in time complexity. In order to clearly describe these algorithms, it lists or introduces several concepts. After the theoretic analysis of the three FSynC algorithms, we find the time complexity can be decreased by using an R-tree index structure or by combining a multi-dimensional grid cell partitioning method with a Red-Black tree structure to construct the near neighbor point sets of all points. In the simulations, SynC algorithm is used as the comparative algorithm of three FSynC algorithms. From the simulated experiments of some artificial data sets, seven UCI data sets, and three picture data sets, we observe that the three FSynC algorithms need less time cost than SynC algorithm in many kinds of data sets. So we can say our three fast synchronization clustering algorithms can replace SynC algorithm with less time cost in many kinds of data sets. At last, it gives several solid and insightful future research suggestions. [ABSTRACT FROM AUTHOR]

In the field of vehicular wireless sensor networks-based structural health monitoring, the structural damage identification is achieved by two structural features, namely natural frequencies and mode shapes. The kind of data fusion-based routing algorithm in specific applications needs to meet time synchronization requirements and meet certain constraints, such as the single-hop communication between cluster head node and each node in cluster, the overlap between different clusters and so on. To meet the special constraints for data fusion-based routing algorithm in structural health monitoring, this paper proposed a new method based on an improved flooding time synchronization protocol, which is called time synchronization and enhanced greedy algorithm based on D(v) (TSDEGA) routing algorithm. The TSDEGA method can achieve the minimum connected cover by node's own degree D(v), and it can also meet the structural health monitoring routing constraints. The simulation experiments show that TSDEGA has better energy resistance and longer network lifetime, and it is superior to the traditional greedy algorithms. The proposed algorithm can effectively eliminate interference of outliers and improve the accuracy in order to meet time synchronization requirements in structural health monitoring applications. [ABSTRACT FROM AUTHOR]

State feedback control design to make the response Boolean network synchronize with the drive Boolean network is far from being solved in the literature. Motivated by this, this paper studies the feedback control design for the complete synchronization of two coupled Boolean networks with time delays. A necessary condition for the existence of a state feedback controller is derived first. Then the feedback control design procedure for the complete synchronization of two coupled Boolean networks is provided based on the necessary condition. Finally, an example is given to illustrate the proposed design procedure. [ABSTRACT FROM AUTHOR]

With the emerging Internet of Things (IoT) technology becoming reality, a number of applications are being proposed. Several of these applications are highly dependent on wireless sensor networks (WSN) to acquire data from the surrounding environment. In order to be really useful for most of applications, the acquired data must be coherent in terms of the time in which they are acquired, which implies that the entire sensor network presents a certain level of time synchronization. Moreover, to efficiently exchange and forward data, many communication protocols used in WSN rely also on time synchronization among the sensor nodes. Observing the importance in complying with this need for time synchronization, this work focuses on the second synchronization problem, proposing, implementing and testing a time synchronization service for low-power WSN using low frequency real-time clocks in each node. To implement this service, three algorithms based on different strategies are proposed: one based on an auto-correction approach, the second based on a prediction mechanism, while the third uses an analytical correction mechanism. Their goal is the same, i.e., to make the clocks of the sensor nodes converge as quickly as possible and then to keep them most similar as possible. This goal comes along with the requirement to keep low energy consumption. Differently from other works in the literature, the proposal here is independent of any specific protocol, i.e., it may be adapted to be used in different protocols. Moreover, it explores the minimum number of synchronization messages by means of a smart clock update strategy, allowing the trade-off between the desired level of synchronization and the associated energy consumption. Experimental results, which includes data acquired from simulations and testbed deployments, provide evidence of the success in meeting this goal, as well as providing means to compare these three approaches considering the best synchronization results and their costs in terms of energy consumption. [ABSTRACT FROM AUTHOR]

Data distribution via Content Delivery Networks (CDNs) is one of the most significant energy consuming sectors in the ICT area. A CDN system can be abstracted as a primary server housing the entire data set and several surrogate servers, each one caching a portion of the whole data set. We propose a new model to compute the total energy consumption of CDNs. The model is based on a hierarchical Internet representation, and includes the energy consumption needed to keep servers synchronized. We analyze the effect of synchronization and network topology on the total energy consumption of CDNs. Results reveal that increasing the number of surrogate servers reduces the transmission delay. However, this does not necessarily lead to a reduction of the total energy consumption. Furthermore, the effect of network topology and various caching strategies is described. Results show that CDN energy consumption strongly depends on the ratio between the number of content requests and content modifications, and considering a hierarchical network topology highlights slightly different energy consumption trends with respect to those of classical “flat” network representation. [ABSTRACT FROM AUTHOR]

In this paper, the synchronization problem of T chaotic system and Lu chaotic system is studied. The parameter of the drive T chaotic system is considered unknown. An adaptive projective lag control method and also parameter estimation law are designed to achieve chaos synchronization problem between two chaotic systems. Then Lyapunov stability theorem is utilized to prove the validity of the proposed control method. After that, some numerical simulations are performed to assess the performance of the proposed method. The results show high accuracy of the proposed method in control and synchronization of chaotic systems. [ABSTRACT FROM AUTHOR]

The ubiquity of multicore processors has led programmers to write parallel and concurrent applications to take advantage of the underlying hardware and speed up their executions. In this context, Transactional Memory (TM) has emerged as a simple and effective synchronization paradigm, via the familiar abstraction of atomic transactions. After many years of intense research, major processor manufacturers (including Intel) have recently released mainstream processors with hardware support for TM (HTM). In this work, we study a relevant issue with great impact on the performance of HTM. Due to the optimistic and inherently limited nature of HTM, transactions may have to be aborted and restarted numerous times, without any progress guarantee. As a result, it is up to the software library that regulates the HTM usage to ensure progress and optimize performance. Transaction scheduling is probably one of the most well-studied and effective techniques to achieve these goals. However, these recent mainstream HTMs have some technical limitations that prevent the adoption of known scheduling techniques: unlike software implementations of TM used in the past, existing HTMs provide limited or no information on which memory regions or contending transactions caused the abort. To address this crucial issue for HTMs, we propose Seer, a software scheduler that addresses precisely this restriction of HTM by leveraging on an online probabilistic inference technique that identifies the most likely conflict relations and establishes a dynamic locking scheme to serialize transactions in a fine-grained manner. The key idea of our solution is to constrain the portions of parallelism that are affecting negatively the whole system. As a result, this not only prevents performance reduction but also in fact unveils further scalability and performance for HTM. Via an extensive evaluation study, we show that Seer improves the performance of the Intel's HTM by up to 3.6×, and by 65% on average across all concurrency degrees and benchmarks on a large processor with 28 cores. [ABSTRACT FROM AUTHOR]

A number of multichannel medium access control (MAC) protocols have been developed earlier with the objective of maximizing energy efficiency and guaranteeing QoS requirements in wireless sensor networks. However, the trade-off between energy efficiency and QoS requirements remains an open issue. In this paper, we propose an energy efficient multichannel MAC protocol, so that nodes dynamically switch their interface between the channels to achieve this goal. The proposed protocol works in two phases, the advertisement (ADV) phase and data phase, which run concurrently. During the ADV phase, the nodes having data try to contend the advertisement channel to transmit the ADV packet. The nodes after receiving the acknowledgment from the receiver switch to the available free channel for the communication of the data packet. We analyze the performance of our proposed protocol through simulation. The simulation results reveal the proposed protocol performs better than the existing MAC protocols in terms of the energy efficiency, data delivery ratio, and end-to-end delay. [ABSTRACT FROM AUTHOR]

Recent advances in Convolutional Neural Networks (CNNs) have obtained promising results in difficult deep learning tasks. However, the success of a CNN depends on finding an architecture to fit a given problem. A hand-crafted architecture is a challenging, time-consuming process that requires expert knowledge and effort, due to a large number of architectural design choices. In this article, we present an efficient framework that automatically designs a high-performing CNN architecture for a given problem. In this framework, we introduce a new optimization objective function that combines the error rate and the information learnt by a set of feature maps using deconvolutional networks (deconvnet). The new objective function allows the hyperparameters of the CNN architecture to be optimized in a way that enhances the performance by guiding the CNN through better visualization of learnt features via deconvnet. The actual optimization of the objective function is carried out via the Nelder-Mead Method (NMM). Further, our new objective function results in much faster convergence towards a better architecture. The proposed framework has the ability to explore a CNN architecture’s numerous design choices in an efficient way and also allows effective, distributed execution and synchronization via web services. Empirically, we demonstrate that the CNN architecture designed with our approach outperforms several existing approaches in terms of its error rate. Our results are also competitive with state-of-the-art results on the MNIST dataset and perform reasonably against the state-of-the-art results on CIFAR-10 and CIFAR-100 datasets. Our approach has a significant role in increasing the depth, reducing the size of strides, and constraining some convolutional layers not followed by pooling layers in order to find a CNN architecture that produces a high recognition performance. [ABSTRACT FROM AUTHOR]

Recent years have witnessed the booming popularity of CLS platforms, through which numerous amateur broadcasters live stream their video contents to viewers around the world. The heterogeneous qualities and formats of the source streams, however, require massive computational resources to transcode them into multiple industrial standard quality versions to serve viewers with distinct configurations, and the delays to the viewers of different locations should be well synchronized to support community interactions. This article attempts to address these challenges and to explore the opportunities with new generation computation paradigms, in particular, fog computing. We present a novel fog-based transcoding framework for CLS platforms to offload the transcoding workload to the network edge (i.e., the massive number of viewers). We evaluate our design through our PlanetLab-based experiment and real-world viewer transcoding experiment. [ABSTRACT FROM PUBLISHER]

In this paper, we introduce the Rotating skip list, the fastest concurrent skip list to date. Existing concurrent data structures experience limited scalability with the growing core count for two main reasons: threads contend while accessing the same shared data, and they require off-chip communication to synchronize. Our solution combines the rotation of a tree to maintain logarithmic complexity deterministically, a skip list structure to avoid the tree root bottleneck, and no locks to limit cache line bouncing. This combination requires us to trade usual skip list towers for wheels, a novel algorithmic design that favors spatial locality and allows for a constant-time restructuring operation. We evaluate the performance of our skip list on AMD Opteron and Intel Xeon multicores, show that its rotations guarantee its balance and compare its performance against seven state-of-the-art skip lists and trees using four different synchronisation techniques. The Rotating skip list shows an unprecedented peak performance of 200 Mops/second. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper situates itself in the theory of variable length codes and of finite automata where the concepts of completeness and synchronization play a central role. In this theoretical setting, we investigate the problem of finding upper bounds to the minimal length of synchronizing words and incompletable words of a finite language X in terms of the length of the words of X . This problem is related to two well-known conjectures formulated by Černý and Restivo, respectively. In particular, if Restivo's conjecture is true, our main result provides a quadratic bound for the minimal length of a synchronizing pair of any finite synchronizing complete code with respect to the maximal length of its words. [ABSTRACT FROM AUTHOR]