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Chemical reaction networks can be utilised as basic components for nucleic acid feedback control systems' design for Synthetic Biology application. DNA hybridisation and programmed strand-displacement reactions are effective primitives for implementation. However, the experimental validation and scale-up of nucleic acid control systems are still considerably falling behind their theoretical designs. To aid with the progress heading into experimental implementations, we provide here chemical reaction networks that represent two fundamental classes of linear controllers: integral and static negative state feedback. We reduced the complexity of the networks by finding designs with fewer reactions and chemical species, to take account of the limits of current experimental capabilities and mitigate issues pertaining to crosstalk and leakage, along with toehold sequence design. The supplied control circuits are quintessential candidates for the first experimental validations of nucleic acid controllers, since they have a number of parameters, species, and reactions small enough for viable experimentation with current technical capabilities, but still represent challenging feedback control systems. They are also well suited to further theoretical analysis to verify results on the stability, performance, and robustness of this important new class of control systems. [ABSTRACT FROM AUTHOR]

As applications move to the edge, efficiency in computing power and power/energy consumption is required. Heterogeneous computing promises to meet these requirements through application-specific hardware accelerators. Runtime adaptivity might be of paramount importance to realize the potential of hardware specialization, but further study is required on workload retargeting and offloading to reconfigurable hardware. This article presents our framework for the exploration of both offloading and hardware generation techniques. The framework is currently able to process instruction sequences from MicroBlaze, ARMv8, and riscv32imaf binaries, and to represent them as Control and Dataflow Graphs for transformation to implementations of hardware modules. We illustrate the framework's capabilities for identifying binary sequences for hardware translation with a set of 13 benchmarks. [ABSTRACT FROM AUTHOR]

The breakdown of Dennard scaling has resulted in a decade-long stall of the maximum operating clock frequencies of processors. To mitigate this issue, computing shifted to multi-core devices. This introduced the need for programming flows and tools that facilitate the expression of workload parallelism at high abstraction levels. However, not all workloads are easily parallelizable, and the minor improvements to processor cores have not significantly increased single-threaded performance. Simultaneously, Instruction Level Parallelism in applications is considerably underexplored. This article reviews notable approaches that focus on exploiting this potential parallelism via automatic generation of specialized hardware from binary code. Although research on this topic spans over more than 20 years, automatic acceleration of software via translation to hardware has gained new importance with the recent trend toward reconfigurable heterogeneous platforms. We characterize this kind of binary acceleration approach and the accelerator architectures on which it relies. We summarize notable state-of-the-art approaches individually and present a taxonomy and comparison. Performance gains from 2.6× to 5.6× are reported, mostly considering bare-metal embedded applications, along with power consumption reductions between 1.3× and 3.9×. We believe the methodologies and results achievable by automatic hardware generation approaches are promising in the context of emergent reconfigurable devices. [ABSTRACT FROM AUTHOR]

• The structured singular value (μ) robustness analysis framework is extended to evaluate nucleic acid controllers for biomolecular processes. • We show that representation of linear feedback controllers with chemical reaction networks introduces nonlinear dynamics, with equilibria that move due to parametric uncertainty. • μ -analysis identifies worst-case parameterisations missed by Monte Carlo simulations. In the field of synthetic biology, theoretical frameworks and software tools are now available that allow control systems represented as chemical reaction networks to be translated directly into nucleic acid-based chemistry, and hence implement embedded control circuitry for biomolecular processes. However, the development of tools for analysing the robustness of such controllers is still in its infancy. An interesting feature of such control circuits is that, although the transfer function of a linear system can be easily implemented via a chemical network of catalysis, degradation and annihilation reactions, this introduces additional nonlinear dynamics, due to the annihilation kinetics. We exemplify this problem for a dynamical biomolecular feedback system, and demonstrate how the structured singular value (μ) analysis framework can be extended to rigorously analyse the robustness of this class of system. We show that parametric uncertainty in the system affects the location of its equilibrium, and that this must be taken into account in the analysis. We also show that the parameterisation of the system can be scaled for experimental feasibility without affecting its robustness properties, and that a statistical analysis via Monte Carlo simulation fails to uncover the worst-case uncertainty combination found by μ -analysis. [ABSTRACT FROM AUTHOR]

The two projects presented in this paper can be used either as two separate assignments in two different semesters or as a final assignment for undergraduate students of electrical engineering. They have two main objectives: first, to teach basic electronic circuit design concepts and, second, to motivate the students to learn more about analog circuit design. The two projects are: 1) the design of an audio power amplifier, and 2) the design of an amplitude-modulated optical link with a pulsed light-emitting diode (LED) at the emitter and a photodiode and a transimpedance amplifier at the receiver. An audio signal is used to modulate the oscillator that drives the LED, and the receiver demodulates this signal to produce an audio signal (music, for example) that can be sent to a loudspeaker. The intent of this optical communication system was to allow students to design and build various electronic circuits that have an overall objective and a clear practical application. Students are motivated by using this system to transmit, receive, and listen to their own music. [ABSTRACT FROM PUBLISHER]

An energy-harvesting system requires an energy-storing device to store the energy retrieved from the surrounding environment. Rechargeable batteries are commonly used to store this energy; however, because of the limited number of charge/discharge cycles, they need to be periodically replaced. A supercapacitor, which has, ideally, a limitless number of charge/discharge cycles, avoids this problem. In this case, it is required for the power management unit to produce a constant output voltage as the supercapacitor discharges. This paper presents a system with a multiratio switched capacitor DC-DC converter, in a 130-nm technology, with a maximum output power of 2 mW, a maximum efficiency of 79.63% and a maximum output ripple, in the steady state, of 23 mV for an input voltage range of 2.3-0.87 V. The proposed converter has four operation states, to maximize its efficiency, that correspond to the conversion ratios of 1/2, 2/3, 1/1 and 3/2. Its clock frequency is automatically adjusted to produce a stable output voltage of 1 V. These features are implemented through two distinct controller circuits that use two asynchronous time machines to dynamically adjust the clock frequency and to select the active state of the converter. All the theoretical expressions as well as the behaviour of the whole system were verified by using electrical simulations. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: This paper presents an automatic procedure for the design and optimization of switched‐capacitor (SC) filters, including the automatic sizing of transistors in the amplifiers and switches. The optimization procedure is based on genetic algorithms (GAs) where the circuit's fitness is first computed using equations describing the filter's transfer function and then using transient simulations. These equations are obtained using a fast numerical methodology that takes into consideration the electrical behavior of all components in the circuit. The poles and zeros of the SC filter's transfer function are computed using a system of differential equations, obtained from the inspection of the circuit. This system describes the filter's behavior for all switch combinations, including the non‐ideal effects of the transistors in the switches and amplifiers. Due to the low computational effort and accuracy of this methodology, it is possible to use a large population in the GA. After finding a solution through equations, the more computationally intensive SPICE transient simulations are used to fine‐tune the solution, with a much smaller population in the GA. Taking advantage of the equations' low computational load and accuracy, process, voltage, temperature (PVT) corners and mismatch errors optimizations are also performed, allowing the chromosomes fitness to be calculated taking into consideration multiple cases, thus resulting in a low sensitivity design. [ABSTRACT FROM AUTHOR]

Summary: This paper presents an overview of design techniques to reduce the capacitance spread of SC notch filters. Three of these techniques are used in the design of a 50‐Hz notch filter, intended for an internet of things (IoT) water management sensor node. In this application, due to the high sampling frequency required by the acquisition channel's ADC, the filter's Fs/fp ratio becomes excessively large, resulting in a capacitance spread of 3225.8, if a conventional SC implementation is used. Using charge division networks, with up to seven share/reset cycles, the filter's capacitance spread is reduced by a factor 12.9 and the total capacitance by 5.9, and a total power dissipation of approximately 262 μW, for a supply voltage of 0.9 V. Using capacitive T‐cell networks, the filter's capacitance spread is reduced by a factor 40.5 and the total capacitance by 14.2. Using partial charge transfer networks, the filter's capacitance spread is improved by a factor 41.6, and the total capacitance by 10.0. The filter's total power consumption, using the last two techniques, is approximately 11 μW. [ABSTRACT FROM AUTHOR]

In this study, a bespoke sliding mode non-linear observer and a linear controller framework is proposed for achieving robust formation control of a cluster of satellites in the case of a circular reference orbit. Exploiting the structure of the satellite dynamics, a non-linear observer is proposed based on super-twist sliding mode ideas. The observer estimates the states and any unknown bounded disturbances in 'finite time'. The stability properties of the observers are demonstrated using Lyapunov techniques. A distributed controller, based on the estimated states and the relative position output information, depending on the underlying communication topology, is proposed. A polytopic representation of the collective dynamics which depends on the eigenvalues of the Laplacian matrix associated with the communication topology is used to synthesise the gains of the proposed control laws. A simulation example is used to demonstrate the efficacy of the proposed approach. [ABSTRACT FROM AUTHOR]

In this study, a bespoke sliding mode non‐linear observer and a linear controller framework is proposed for achieving robust formation control of a cluster of satellites in the case of a circular reference orbit. Exploiting the structure of the satellite dynamics, a non‐linear observer is proposed based on super‐twist sliding mode ideas. The observer estimates the states and any unknown bounded disturbances in 'finite time'. The stability properties of the observers are demonstrated using Lyapunov techniques. A distributed controller, based on the estimated states and the relative position output information, depending on the underlying communication topology, is proposed. A polytopic representation of the collective dynamics which depends on the eigenvalues of the Laplacian matrix associated with the communication topology is used to synthesise the gains of the proposed control laws. A simulation example is used to demonstrate the efficacy of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper describes an energy harvesting system composed of an organic photovoltaic cell (OPV) connected to a DC–DC converter, designed in a 130 nm Complementary Metal-Oxide-Semiconductor (CMOS) technology, with a quasi- maximum power point tracking (MPPT) algorithm to maximize the system efficiency, for indoor applications. OPVs are an emerging technology with potential for low cost indoor light energy harvesting. The OPV current-voltage curves (I-V) under an irradiance of solar simulator Oriel Sol 3A, at room temperature, are obtained and an accurate electrical model is derived. The energy harvesting system is subjected to four different indoor light sources: 35 W halogen, 3.5 W LED, 5 W LED, and 7 W LED, positioned at three different heights (0.45 m, 0.26 m, and 0.11 m), to evaluate the potential of the system for indoor applications. The measurements showed maximum efficiencies of 60% for 35 W halogen and 45% for 7 W LED at the highest distance (0.45 m) and between 60% (5 W LED) and 70% (35 W halogen), at the shorter distance (0.11 m). Under irradiation, the integrated CMOS circuit presented a maximum efficiency of 75.76%, which is, to the best of the authors' knowledge, the best reported power management unit (PMU) energy system using organic photovoltaic cells. [ABSTRACT FROM AUTHOR]

The article presents the results of a study which examined the safety of autonomous rendezvous guidance, navigation, and control (GNC) systems in Mars sample return (MSR) based on verification and validation (VV) techniques. Topics discussed include the use of a customized high-integrity autonomous rendezvous and docking (HARVD) functional engineering simulator, an overview of the integrative VV framework and worst-case results using different integrated methods.