Synchronous Design Research Articles

Quasi Delay Insensitive Majority Voters for Triple Modular Redundancy Applications

Mission- and safety-critical applications tend to incorporate triple modular redundancy (TMR) in their hardware implementation to reliably withstand the fault or failure of any one of the function modules during normal operation, and the function module may be a circuit or a system. In a TMR implementation, two identical copies of a function module are used in addition to the original function module, and the correct operation of at least two function modules is required. In TMR, the corresponding primary outputs of the three function modules are combined using majority voters, which determine the actual primary outputs based on the Boolean majority. Hence, the majority voter is an important component that is useful for conveying the correct operation of a TMR implementation. In the existing literature, many designs of three-input majority voters for TMR have been discussed. However, most of these correspond to the synchronous design style and just one corresponds to the bundled-data asynchronous design style, which is not delay insensitive and hence non-robust. To our knowledge, a robust delay insensitive design of the three-input majority voter has not been considered. In this context, this article presents the designs of robust quasi delay insensitive (QDI) three-input majority voters based on QDI logic synthesis methods, and analyzes which majority voters are preferable in terms of speed, power, and area. We implement example QDI TMR circuits using a QDI full adder as the function module and QDI majority voters using 32/28 nm complementary metal oxide semiconductor (CMOS) technology. The QDI TMR implementations use the delay insensitive dual rail code for data encoding, and four-phase return-to-zero and four-phase return-to-one handshake protocols for data communication.

Wearables Clock Synchronization Using Skin Electric Potentials

Design of clock synchronization for networked nodes faces a fundamental trade-off between synchronization accuracy and universality of heterogeneous platforms, because a high synchronization accuracy generally requires platform-dependent hardware-level network packet timestamping. This paper presents TouchSync , a new indoor clock synchronization approach for wearables that achieves millisecond accuracy while preserving universality in that it uses standard system calls only, such as reading system clock, sampling sensors, and sending/receiving network messages. The design of TouchSync is driven by a key finding from our extensive measurements that the skin electric potentials (SEPs) induced by powerline radiation are salient, periodic, and synchronous on a same wearer and even across different wearers. TouchSync integrates the SEP signal into the universal principle of Network Time Protocol and solves an integer ambiguity problem by fusing the ambiguous results in multiple synchronization rounds to conclude an accurate clock offset between two synchronizing wearables. With our shared code, TouchSync can be readily integrated into any wearable applications. Extensive evaluation based on our Arduino and TinyOS implementations shows that TouchSync's synchronization errors are below 3 and 7 milliseconds on the same wearer and between two wearers 10 kilometers apart, respectively.

Inverse approach for concentrated winding surface permanent magnet synchronous machines noiseless design

Abstract The electromagnetic noise generated by the Maxwell radial pressure is a well-known consequence. In this paper, we present an analytical tool that allows air gap spatio-temporal pressures to be obtained from the radial flux density created by surface permanent magnet synchronous machines with concentrated winding (SPMSM). This tool based on winding function, a global air-gap permeance analytical model and total magnetomotive force product, determines the analytical air-gap spatio temporal and spectral radial pressure.We will see step-by-step their impacts in generating noise process. Also two predictive methods will be presented to determine the origin of the lows radial pressure orders noise sources. The interest lies in keeping results very quickly and appropriate in order to identify the low order electromagnetic noise origin. Then through an inverse approach using an iterative loop a new winding function is proposed in order to minimize radial force low order previously identified and chosen.

The energy cost and optimal design for synchronization of coupled molecular oscillators.

A model of coupled molecular biochemical oscillators is proposed to study nonequilibrium thermodynamics of synchronization. We find that synchronization of nonequilibrium oscillators costs addition energy to drive the exchange reaction (chemical interaction) between individual oscillators. By solving the steady state of the many-body system analytically, we show that the system goes through a nonequilibrium phase transition driven by energy dissipation, and the critical energy dissipation depends on both the frequency and strength of the exchange reaction. Moreover, our study reveals the optimal design for achieving maximum synchronization with a fixed energy budget. We apply our general theory to the Kai system in Cyanobacteria circadian clock and predict a relationship between the KaiC ATPase activity and synchronization of the KaiC hexamers. The theoretical framework can be extended to study thermodynamics of collective behaviors in other extended nonequilibrium active systems.

Single-Phase Enhanced Phase-Locked Loops Based on Multiple Delayed Signal Cancellation Filters for Micro-Grid Applications

The grid voltage information such as the phase-angle, the frequency, and the amplitude is crucial for the design of synchronization and control of power converters in the micro-grid. The conventional approach to estimate the grid voltage information is accomplished by phase-locked loop (PLL) techniques. Among various existing PLL techniques, filter-based PLLs can provide more accurate estimations even under adverse grid conditions. In this paper, a new single-phase filtering technique based on multiple delayed signal cancellation (MDSC) is proposed for extracting both in-phase and quadrature components of the selected harmonic order of the single-phase grid voltage signal. This MDSC technique can be realized in both the direct-form and the recursive-form. In comparison with existing single-phase cascaded delayed signal cancellation (CDSC) techniques, this MDSC technique utilizes less memory for the extraction of grid voltage fundamental frequency component. The proposed MDSC filter can be applied as a pre-filter to the enhanced PLL (EPLL) for the prompt and accurate estimations of the grid voltage information under adverse grid conditions. Both frequency adaptive and non-adaptive MDSC-based EPLL schemes are proposed in this paper. To validate the effectiveness of the proposed methods, experiments are conducted on the MDSC-based EPLLs and compared with the CDSC-EPLL under various grid voltage disturbances.

Controller design for fixed-time synchronization of nonlinear coupled Cohen–Grossberg neural networks with switching parameters and time-varying delays based on synchronization dynamics analysis

This paper addresses the fixed-time synchronization controller design problem for a class of nonlinear coupled Cohen–Grossberg neural networks (NCCGNNs) with switching parameters and time-varying delays based on synchronization dynamics analysis. First, a class of NCCGNNs with switching parameters and time-varying delays are considered. Second, according to the derived sufficient condition, a fixed-time synchronization controller is designed. Moreover, the advantages and disadvantages of the designed controller are discussed. Third, to improve the disadvantages of the obtained control method, by using synchronization dynamics analysis, some fixed-time synchronization controllers are further designed. Finally, two examples illustrate the usefulness and feasibility of the derived theoretical results.

Event-triggered mixed [formula omitted] and passive filtering for discrete-time networked singular Markovian jump systems

The mixed H∞ and passive filtering problem for a class of discrete-time networked singular Markovian jump systems (SMJSs) is investigated in this paper. To reduce transmission of signals in the limited bandwidth networks, a novel event-triggered scheme (ETS) is proposed. A networked singular Markovian jump filtering error system (FES) with time-delay is established by considering the network communication characteristic and the ETS. By utilizing Lyapunov–Kravoskii stability theory, some new criteria are derived in the form of linear matrix inequalities (LMIs) such that the FES is stochastically admissible (SA) and has a prescribed level of mixed H∞ and passive performance. The co-design method is given, which can realize the synchronous design for the filter and ETS parameters. The proposed method can deal with the mode-dependent or mode-independent filter design problems for SMJSs including H∞, passive and mixed filter (i.e., mixed H∞ and passive filter) in a unified form. Finally, three numerical examples are provided to illustrate the effectiveness of the proposed method.

Decentralized Control for Guaranteed Individual Costs in a Linear Multi-Agent System: A Satisfaction Equilibrium Approach

This letter focuses on the design of decentralized feedback control gains that aims at optimizing individual costs in a multi-agent synchronization problem. As reported in the literature, the optimal control design for synchronization of agents using local information is NP-hard. Consequently, we relax the problem and use the notion of satisfaction equilibrium from game theory to ensure that each individual cost is guaranteed to be lower than a given threshold. Our main results provide conditions in the form of linear matrix inequalities (LMIs) to check if a given set of control gains are in satisfaction equilibrium, i.e., all individual costs are upper-bounded by the imposed threshold. Moreover, we provide an algorithm in order to synthesize gains that are in satisfaction equilibrium. Finally, we illustrate this algorithm with numerical examples.

Impulsive observer with predetermined finite convergence time for synchronization of fractional-order chaotic systems based on Takagi–Sugeno fuzzy model

This paper is devoted to the problem of observer design for synchronization of nonlinear fractional-order chaotic systems described by the Takagi–Sugeno fuzzy model. We propose a new method of designing an observer that converges in finite time. The novelty of the proposed observer compared to those developed in the literature is that the estimated state exactly converges to the true state in a finite time which can be chosen beforehand. This is made possible by updating the estimated state at a defined time instant. The abrupt update shows up an impulsive behavior of the observer’s dynamics. Two cases are considered. In the first case, the system is not affected by an unknown input. The second case considers the system subjected to the action of an unknown input. Finite-time convergence of the two proposed observers for both cases is established using linear matrix inequality formulation. Simulation results on the synchronization of fractional-order chaotic systems clearly illustrate the impulsive behavior of the proposed observer and the predefined finite-time synchronization. The advantage of predefined finite-time synchronization is highlighted by the ability of recovering an encrypted message without loss of information in a fractional-order chaos-based secure communication application.

Electronic storybook design, kindergartners' visual attention, and print awareness: An eye-tracking investigation

The purpose of this study was to understand children's visual attention during shared storybook reading when the print and picture area sizes are identical, as well as to understand which electronic storybook design is best able to increase children's attention to the print and their print awareness. To this end, we modified the electronic storybook's design, measured children's print awareness, and used an eye-tracker to measure children's visual attention during reading. Sixty-one 4–5 year old Taiwanese children's data were analyzed in this study. This study was conducted over a 6-week period: one week for pretest, four weeks of intervention, and one week for posttest. After the pretest stage, the kindergartners were split into three groups: traditional storybook, highlight synchronization (implicit instruction), and print discussion (explicit instruction). The results suggested that: First, when the print and picture area sizes were identical, children spent more than 19% of their time looking at the print area, substantially higher than previous studies (e.g. Evans & Saint-Aubin, 2005; Justice, Skibbe, Canning, & Lankford, 2005; Roy-Charland, Perron, Boulard, Chamberland, & Hoffman, 2015); second, the highlight synchronization design did entice children to look at the print more (from 19% to 38% reading time); third, exposure to either the reading highlight synchronization or the print discussion storybook designs for four weeks improved the children's print awareness.

Adaptive control of Mittag-Leffler stabilization and synchronization for delayed fractional-order BAM neural networks

This paper is committed to studying adaptive control design of Mittag-Leffler stabilization and synchronization for delayed fractional-order bidirectional associative memory (BAM) neural networks. Considering better dynamic property and steady state performance of the system, we adopt adaptive control approaches to stabilize and synchronize two types of delayed fractional-order BAM neural network. It is a remarkable fact, based on adaptive control scheme, the method of auxiliary functions, Mittag-Leffler stabilization and synchronization theories with respect to fractional-order systems, the adaptive controllers are very well designed in a controlled system and two coupled systems, separately. Two examples are performed to illustrate the advantage of the presented theoretic analysis and results.

Synchronization control for robot manipulators driven by induction motors with flux and velocity observers

This paper presents a design of synchronization of robot manipulators driven by induction motors in the case where the flux, velocity and currents are estimated. The synchronization is developed in both the joint space and workspace. The [Formula: see text] field oriented frame model of the induction motor is used to design the synchronization control approach. An observer based on the [Formula: see text] frame model is proposed to estimate the flux, velocity and currents variables, then they are converted to the variables of the [Formula: see text] field-oriented model, and finally the remaining variables are estimated by means of an observer based on the [Formula: see text] frame model. Stability is proved via a Lyapunov analysis. Simulations show the proposed controllers yield synchronization errors asymptotically stables in the closed-loop response.

Adaptive State Observers for Incrementally Quadratic Nonlinear Systems with Application to Chaos Synchronization

This paper is concerned with the problem of adaptive state observer design for a class of incrementally quadratic nonlinear systems with parameter uncertainty. Its nonlinearity satisfies the condition of incremental quadratic constraints which contains many commonly encountered nonlinearities in existing literature as some special cases. A circle criterion-based adaptive observer is first designed to expand the freedom of observer design. Based on the incremental quadratic constraint condition, sufficient conditions ensuring asymptotic stability of estimation error dynamics are established in terms of linear matrix inequalities. Finally, the adaptive observer is applied to the synchronization design of chaotic systems with parameter uncertainty, which fully demonstrates the effectiveness of the proposed observer.

IEEE 802.11ba: Low-Power Wake-Up Radio for Green IoT

Low-power devices have manifested their crucial roles in manifold green Internet of Things (IoT) applications, including healthcare, smart home, industrial sensors, and wearable apparatuses. However, to prolong the operation time of these devices, significantly enhancing the battery capacity turns out to be an intractable challenge due to the mandatory constraint of limited form factors. Achieving this goal thus inevitably relies on new designs of physical-layer (PHY)and medium access control (MAC) schemes. This desire has driven IEEE 802.11 Task Group ba (TGba) to launch the normative work of wake-up radios (WURs) since 2017. To comprehend essential knowledge of this new technical feature, in this article, we consequently offer substantial insights of IEEE 802.11ba, including the deployment scenarios, PHY operations (waveform, modulation, data rate selection, and synchronization design), and MAC operations (radio wake-up procedure, WUR duty cycle, WUR mode, channel access scheme, and the format of a MAC packet data unit). The provided insights facilitate further research and implementation of IEEE 802.11ba WUR to empower the next generation green IoT.

Self‐start synchronous reluctance motor new rotor designs and its performance characteristics

Self‐start synchronous reluctance motor new rotor designs and its performance characteristics

Lyapunov approach for motion synchronization of a two-slider system

This paper focuses on a novel boundary control design for motion synchronization of a two-slider system. In this system, two sliders are constrained by a flexible beam. The de-synchronization of two sliders will result in the interaction between them. The interaction force is considered as shear force in this paper. Based on the shear force coupling, the system models are derived. In order to obtain an accurate representation, the flexible beam is derived as a distributed parameter system with one partial differential equation. Based on the proposed models, a Lyapunov approach is used to design the boundary control laws for two sliders to realize the synchronization motion. Simulations are provided to illustrated that the proposed method can effectively improve the sync motion performance compared with the cross-coupling method.

Development of the legal framework of recreational nature management in Russia

The article traces the history of the development of legal legislation related to the recreational development of the territory. Five stages of formation are considered. For each stage the types of recreational areas are characterized. These types are reflected in the regulatory legal acts of each time period. Recreational nature management takes a significant place in the structure of nature management in Russia. It's modern regulatory and legal framework is analyzed in particular. The study revealed the main problems of involving territories in the recreational sphere from the standpoint of the main normative documents — the codes of the Russian Federation: Land, Water, Forest and Town-planning and Federal laws supplementing them. The analysis of the current legislation and the terminology used in it provides the basis for the correlation of recreational nature management with five categories of land: forest lands, agricultural lands, water resources, build-up areas (settlements) and lands of specially protected areas and objects. The necessity of integration of the concepts of «cultural landscape», «landscape planning» and «landscape plan» in the legal field with the aim of streamlining the process of planning and design of recreational areas and synchronization of the legislation in the sphere of recreational nature management is suggested in the article.

DEVELOPMENT OF TECHNOLOGY AND COMPARATIVE ANALYSIS OF CREATING THREE-DIMENSIONAL MODELS IN MODERN CAD SYSTEMS TAKING INTO ACCOUNT THE FORMATION PROCESSES BY CUTTING

A sequence over of development of computer is brought technologies on creation of model of detail with the use of various approaches. The self-reactance planning, direct design is considered, (without the tree of construction and hard connections between structural elements), variation design. Similar decisions were used exceptionally for to the 2d-sketch and constructions of connections "from top to bottom" for frame-clamping knots that did not embrace a three-dimensional design. A situation changed with appearance of synchronous technology, that was able to spread the variation going near a design on all chainlet of planning of good. It is synchronous technology allows to change the functional of direct design directly in a self-reactance environment. The algorithm of creation of three-dimensional model of detail is worked out in a synchronous environment. In an algorithm thoroughly to consider all stages of creation of three-dimensional model of detail from a requirement specification to the model and designer documentation. The technology of creating a three-dimensional model details the type of housing in the synchronous design environment of modern CAD Solid Edge. The features of creating and editing a three-dimensional model of the part and its elements are given in detail, taking into account the features of technological processes of forming cutting. It is considered as by means of managing 3d-розмірів and geometrical connections between 3d-об'єктами exact control of geometry is realized in synchronous technology. In Solid Edge with synchronous technology structural elements are independent and kept not in the tree of model, but in a navigator. Computer imitation models allow operatively to investigate and pick up the optimal modes and parameters of technological process, that promotes efficiency, exactness and quality of production considerably. Modern technologies not only simplify work to the engineer-designer, but also considerably cut prime cost production. A comparative analysis of the design in synchronous and parametric environments with an explanation of the advantages and disadvantages. Synchronous technology unites in itself advantages of self-reactance and direct design, and eliminates the lacks of both approaches.

A GALS design based on multi-frequency clocking for digital switching noise reduction

In this paper, we investigate two design techniques to reduce the digital switching noise on the power supply lines: a multi-frequency clocking (MFC) and a globally asynchronous locally synchronous (GALS) design technique. By deploying an MFC design, we can spread the switching current peaks over a frequency band, which results in the supply noise reduction. With the use of a GALS technique, we partition a large synchronous design into some smaller locally synchronous modules (LSMs) which are clocked by their own local clocks. Each local clock signal can be different from the other in terms of frequency or phase. Thus, we can also distribute the digital switching activities inside circuits over time, which leads to the supply noise reductions. The experimental results on a commercial Field Programmable Gate Array (FPGA) Spartan-3 (XC3S400-TQ144) show that the noise reduction rates can be achieved up to 17.4 dB for a GALS system with 8 LSMs, and 19.2 dB for the joint use of the MFC and GALS techniques with 4 LSMs. Moreover, as a real design example, a DES crypto processor with the deployment of GALS design and multi-frequency clocking strategy is also implemented and evaluated. The noise reduction rate is achieved about 19.5 dB at the fundamental frequency.

Implementation of Low Power Null Conventional Logic Function for Configuration Logic Block

Todays, transistor level design plays major impact in the power consumption of the VLSI based design. The various logic design models are used to reduce the power consumption that includes synchronous and asynchronous design model. The operation of synchronous circuit is limited by the in phase factor of the clock pulse signal which is used to control the synchronous circuit. In contrast, asynchronous circuits are used widely because it causes low noise, require less power. It affects the less electromagnetic interference that allows reuse of the components. These asynchronous circuits are being implemented by Null Conventional Logic (NCL) which is a delay insensitive logic model. The Configuration Logic Block is the power consuming model in Field Programmable Gate Array (FPGA). This block contains the lookup table (LUT) and 27 fundamental NCL logic gates. To reduce the power consumption of this module, we use the Differential Cascade Voltage Switch Logic (DVSL). The power reduction is achieved in LUT by means of DVSL and minimizes the number transistors. This NCL, DVSL, FPGA logic element is simulated using 90 nm TSMC CMOS processing technology.