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[Display omitted] • The free-standing, monolithic and anisotropic graphite networks were constructed by a two-stage, economy, facile expansion process. • The sensitivity of the sensors/switches can be accurately tailored. • The wireless monitoring of human movement was realized by integrating the sensors/switches with microelectronic components. Highly sensitive strain sensors and switches are essential components to wearable electronics in many emerging applications such as personal health monitoring, human–machine interaction, smart robots and intelligent control system. Herein, we report a new highly-anisotropic graphite framework (HAGF) for creating strain sensors and switches with high flexibility, stretchability and sensitivity. The highly anisotropic three-dimensional (3D) graphite structure was fabricated via a facile, low-cost and scalable expansion of commercially-available graphite papers. By controlling the orientation structure and thickness of HAGF, the contact area and switchable conduction path can be tailored to create strain sensors and switches based on HAGF/PDMS composites to achieve a tunable gauge factor between 1.3 and 379, an ultra-high ON/OFF ratio in the order of 1035 with tunable critical switching strain (8 % ∼ 50 %), an excellent long-term repeatability of over 1000 cycles at a peak strain of 50 %, and a stretchability up to 100 %. The potentials of the new sensors and switches are demonstrated by pairing them with the smartphone for tracking and recognition of human motions, offering a new solution to a wide range of portable devices and mobile applications. [ABSTRACT FROM AUTHOR]

For maximizing the customer satisfaction and retention, improvement of service reliability is a major concern for electric utilities. Service reliability can be improved by placing switches and reclosers at appropriate locations in the distribution system so that supply from the main substation to the healthy load points can be maintained after isolating the faulted section. This paper presents a formulation for an optimal placement of switches and reclosers in a distribution system for maximizing system reliability while minimizing the associated investment and outage costs considering uncertainties in load data, system failure and repair rates. The uncertainties have been incorporated in the formulation using point estimate method (PEM). The proposed formulation has been tested on 13, 58 and IEEE 123-bus test systems using differential evolution (DE) and mixed integer nonlinear programming (MINLP) method. The obtained results establish the effectiveness of the consideration of data uncertainties in improving the distribution system reliability and maximizing utilities’ profits. [ABSTRACT FROM AUTHOR]

The increasing complexity of integrated circuits drives the research of new on-chip interconnection architectures. A network on chip draws on concepts inherited from distributed systems and computer networks subject areas to interconnect IP cores in a structured and scalable way. The main goal pursued is to achieve superior bandwidth when compared to conventional on-chip bus architectures. This paper reviews the state of the art in networks on chip. Then, it describes an infrastructure called Hermes, targeted to implement packet-switching mesh and related interconnection architectures and topologies. The basic element of Hermes is a switch with five bi-directional ports, connecting to four other switches and to a local IP core. The switch employs an XY routing algorithm, and uses input queuing. The main design objective was to develop a small size switch, enabling its immediate practical use. The paper also presents the design validation of the Hermes switch and of a network on chip based on it. A Hermes NoC case study has been successfully prototyped in hardware as described in the paper, demonstrating the functionality of the approach. Quantitative data for the Hermes infrastructure is advanced. [Copyright &y& Elsevier]

Abstract: Dual pulse actuation voltage waveforms that are capable of mitigating micro-electromechanical system (MEMS) switch bouncing are presented. The displacement and velocity of the MEMS switch membrane actuated using these waveforms are then simulated and compared. To eliminate bouncing, the velocity of the membrane should ideally be zero just before contact is made. Otherwise the large momentum from high velocity impact will bounce the membrane back, extending the switching time and bringing about wear and tear to the contact surfaces. The effect of MEMS switch parameter variations on the bouncing membrane is then studied for switches with different gap widths. The impact of the variation in the voltage waveform is also investigated in this paper. The exponentially saturating dual-pulse actuation waveform has shown great robustness against both switch and voltage waveform parameter variations. The waveform also exhibited the fastest switching time for a wider range of parameters variations. Practical experiments were carried out on TeraVicta TT712-68CSP MEMS switch to corroborate the findings. [Copyright &y& Elsevier]

Abstract: This paper presents a simple and robust process for fabrication of functional electrostatic RF-MEMS switching devices with lifetimes easily exceeding 108 cycles by unipolar actuation at 100Hz. The device implements a switchable air gap capacitor and is therefore not limited in lifetime by dielectric charging as opposed to contact-type capacitive switches implementing high-k dielectrics. Even though these switched air gap capacitors have a rather low capacitance ratio of around 5–6, they can still form adequate switching devices and RF-circuits by making use of properly designed transmission lines and when combined with high-Q inductors. Examples described include tunable notch band filters designed for the 2GHz and 20GHz range and a tunable stop band filter. The novelty of the proposed process is that it combines a sacrificial layer consisting of a single layer with a single dry etching step for the dimples which define the height of the air gap in the down-state. This air gap is switched by electrostatic actuation of a thick (7μm) electroplated nickel bridge structure. The device is realized in a 4 lithographic steps process with low complexity and high robustness. [Copyright &y& Elsevier]

Abstract: This paper presents a multiobjective optimization methodology to optimally place switches and protective devices in electric power distribution networks. Identifying the type and location of them is a combinatorial optimization problem described by a nonlinear and nondifferential function. The multiobjective ant colony optimization (MACO) has been applied to this problem to minimize the total cost while simultaneously minimize two distribution network reliability indices including system average interruption frequency index (SAIFI) and system interruption duration index (SAIDI). Actual distribution feeders are used in the tests, and test results have shown that the algorithm can determine the set of optimal nondominated solutions. It allows the utility to obtain the optimal type and location of devices to achieve the best system reliability with the lowest cost. [Copyright &y& Elsevier]

Abstract: In this paper, we present mechatronic design and analysis of radio-frequency (RF) microelectromechanical system (MEMS) switches with rectangular, taper, and meandering connection beam structures. The mechatronic design and analysis of the RF MEMS switches are based on both the finite element method and the full-wave electromagnetic simulation. The mechanical characteristics of the RF MEMS switches including displacement, stress, and nature frequency are studied. The electronic characteristics of the switches investigated include insertion loss, return loss, and isolation. The comprehensive mechatronics study of the RF MEMS switches provides a systematic design and analysis methodology for MEMS applications. [Copyright &y& Elsevier]

Abstract: Catchment configuration and the nature of connectivity within and between landscape compartments affect the operation of sediment cascades and geomorphic responses to disturbance events of differing magnitude and frequency. This paper introduces the concept of landform impediments, termed buffers, barriers and blankets, that impede sediment conveyance by limiting the connectivity between landscape compartments. Buffers restrict sediment delivery to channels, barriers inhibit sediment movement along channels, and blankets drape channel or floodplain surfaces affecting the accessibility of sediment to entrainment. These features operate as a series of switches which turn on/off processes of sediment delivery, determining the effective catchment area at any given time. Using previously documented examples, the role of these features in affecting the operation of sediment cascades in a low relief, passive landscape setting such as the Australian landmass is contrasted to examples from high relief, uplifting settings in New Zealand. The Australian examples are further explored by examining how changes to landscape connectivity brought about by human disturbance since European settlement have impacted upon landscape sensitivity and prospects for river recovery. This approach to analysis of impediments to sediment conveyance is generic and can be applied in any environmental setting. [Copyright &y& Elsevier]

Abstract: This work focuses on electrostatically actuated micro-electro-mechanical systems (MEMS) capacitive switches, intended for adaptive output stage of power amplifiers. These devices are particularly attractive because theoretically they are capable of very high quality factor values due to the air gap between plates and the low resistivity of lines and bridge. On the other hand, substrate parasitic effects, overlooked up to date, can seriously impair device performance. In this paper, we introduce a lumped element equivalent circuit taking into account substrate effects. Model validation is based on measurements carried out in the 50MHz–40GHz range. [Copyright &y& Elsevier]

The paper gives the construction of a universal CA with 22 states in the regular rectangular pentagonal grid of the hyperbolic plane. The CA implements a railway circuit which simulates a register machine and which improves a bit already known railway simulations of a Turing machine. [Copyright &y& Elsevier]