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In this article, a microstrip antenna having circular polarization switching capability is presented. This antenna consists of a circular-shaped radiating patch with a single co-axial probe feed line. The polarization reconfigurability is achieved by introducing four symmetrical U-shaped slots and silicon PIN diodes on the radiating patch. A prototype of the design is fabricated on an FR-4 substrate with overall dimension of 70 × 70 × 1.6 mm to verify the performances. The measured results of the antenna exhibit an impedance bandwidth (S11 < −10 dB) of 5% in the frequency range of 2.37–2.49 GHz. The maximum gain of the antenna is found to be 2.99 dBic at 2.43 GHz. The antenna shows stable radiation performances at 2.4 GHz with 4.1% of 3-dB axial ratio bandwidth, and more than 105° of 3-dB axial ratio beamwidth for both right-hand circular polarization and left -hand circular polarization which make it suitable for ISM band Smart city applications. [ABSTRACT FROM AUTHOR]

Model predictive control (MPC) in automotive active safety applications has gained great success in recent years. Detailed vehicle models along with a receding horizon control scheme seek the optimal control distribution among actuators for enhanced performances while satisfying system constraints. To promote the re-usability and scalability of MPC-based vehicular active safety systems, an agent-based MPC (AMPC) is proposed in our previous study for a modularized control architecture. In this paper, implementation of the control scheme is demonstrated on an all-wheel-drive test platform. Both centralized and agent-based MPCs for vehicular stability are compared for their control performances as well as computational costs on embedded hardware. It is shown from experimental results that agent-based MPC is more flexible and computationally efficient in handling vehicle active safety challenges while gives no compromise to control performances compared to their holistically formulated counterparts. [ABSTRACT FROM AUTHOR]

We propose and demonstrate a novel linearly frequency modulated (LFM) signal generation method using synchronized lasers in a heterodyne-beating scheme, featuring simple operation, large bandwidth and flexible reconfiguration. A hybrid synchronization mechanism combining the advantages of optical phase-locking and digital signal processing mechanisms maintains the phase coherence between lasers when the wavelength is sweeping. The ability of phase coherence maintaining provides attractive benefits in flexible reconfigurability of beat signal parameters and high scalability of signal bands. A dual-laser synchronization system is established, and an LFM waveform with reconfigurable bandwidth, central frequency and pulse duration is produced. Additionally, an ISAR imaging experiment is carried out. Results show the potential of the proposed method in multifunctional/multiband radar applications. [ABSTRACT FROM AUTHOR]

In the past decades, bone tissue engineering developed and exploited many typologies of bioreactors, which, besides providing proper culture conditions, aimed at integrating those bio‐physical stimulations that cells experience in vivo, to promote osteogenic differentiation. Nevertheless, the highly challenging combination and deployment of many stimulation systems into a single bioreactor led to the generation of several unimodal bioreactors, investigating one or at mostly two of the required biophysical stimuli. These systems miss the physiological mimicry of bone cells environment, and often produced contrasting results, thus making the knowledge of bone mechanotransduction fragmented and often inconsistent. To overcome this issue, in this study we developed a perfusion and electroactive‐vibrational reconfigurable stimulation bioreactor to investigate the differentiation of SaOS‐2 bone‐derived cells, hosting a piezoelectric nanocomposite membrane as cell culture substrate. This multimodal perfusion bioreactor is designed based on a numerical (finite element) model aimed at assessing the possibility to induce membrane nano‐scaled vibrations (with ~12 nm amplitude at a frequency of 939 kHz) during perfusion (featuring 1.46 dyn cm−2 wall shear stress), large enough for inducing a physiologically‐relevant electric output (in the order of 10 mV on average) on the membrane surface. This study explored the effects of different stimuli individually, enabling to switch on one stimulation at a time, and then to combine them to induce a faster bone matrix deposition rate. Biological results demonstrate that the multimodal configuration is the most effective in inducing SaOS‐2 cell differentiation, leading to 20‐fold higher collagen deposition compared to static cultures, and to 1.6‐ and 1.2‐fold higher deposition than the perfused‐ or vibrated‐only cultures. These promising results can provide tissue engineering scientists with a comprehensive and biomimetic stimulation platform for a better understanding of mechanotransduction phenomena beyond cells differentiation. [ABSTRACT FROM AUTHOR]

The fully memristive neural network consisting of the threshold switching (TS) material‐based electronic neurons and resistive switching (RS) one‐based synapses shows the potential for revolutionizing the energy and area efficiency in neuromorphic computing while being confronted with challenges such as reliability and process compatibility between memristive synaptic and neuronal devices. Here, a spiking convolutional neural network (SCNN) is constructed with the forming‐and‐annealing‐free V/VOx/HfWOx/Pt memristive devices. Specifically, both highly reliable RS (endurance >1010, on‐off ratio >103) and TS (endurance >1012) are found in the same device by setting it at RRAM or selector mode with either the HfWOx or naturally oxidized VOx layers dominating the conductance tuning. Such reconfigurability enables the emulation of both synaptic and nonpolar neuronal behaviors within the same device. A V/VOx/HfWOx/Pt‐based hardware system is thus experimentally demonstrated at much simplified process complexity and higher reliability, in which typical neural dynamics including synaptic plasticity and nonpolar neuronal spiking response are imitated. At the network level, a fully memristive SCNN incorporating nonpolar neurons is proposed for the first time. The system level simulation shows competency in pattern recognition with a dramatically reduced hardware consumption, paving the way for implementing fully memristive intelligent systems. [ABSTRACT FROM AUTHOR]

This paper presents a low-profile circularly polarized (CP) antenna with wideband and polarization-reconfigurable characteristics. The proposed antenna consists of a truncated-corner patch working as a CP source and a non-uniform metasurface (MS) acting as parasitic elements for performance enhancement. The non-uniform MS is utilized to produce additional operating bands in the higher frequency range, which are then combined with the lower band produced by the driven patch to significantly broaden the overall operating bandwidth. The polarization switching mechanism is based on the ON/OFF states of two p-i-n diodes. The fabricated prototype shows the measured overlapped bandwidth between −10 dB impedance and 3-dB axial ratio is 25.6% and peak broadside gain is 7.3 dBic.

The reconfiguration of supply chain is becoming a crucial concept used to deal with market disruptions and changes such as the COVID-19 pandemic, demand uncertainty, and new technologies. It can be defined as the ability of the supply chain to change its structure and functions in order to adapt to new changes. Its assessment requires an understanding of its quantitative factors to provide indicators that are easy to interpret. Effective reconfigurability assessment can be achieved by measuring quantitatively its six characteristics (modularity, integrability, convertibility, diagnosability, scalability, and customization). This paper aims at identifying the quantitative factors of each characteristic and their inter-relationships by using Total Interpretive Structural Modelling (TISM). The structural model obtained by TISM is applied to understand the dependency quantitative factors. Based on TISM results, a classification of quantitative factors is determined using "Matrice d′Impacts Croisés, Multiplication Appliquée à un Classement" (MICMAC) analysis. This article provides a better understanding of the six characteristics previously mentioned to improve the reconfigurability of supply chains by considering the interactions between their factors. Thus, this analysis helps managers to understand the characteristics that influence the change of the supply chain structure and those that enable changing the supply chain functions in order to optimize the supply chain reconfiguration process. [ABSTRACT FROM AUTHOR]

Although the concept of Reconfigurable Manufacturing Systems (RMS) has reached its 20th anniversary, it has only grown in relevance. However, the principles are only applied scarcely, although industry recognize the benefits. The transition is limited by a lack of methods which support the practical design of reconfigurable and modular architectures of manufacturing systems and their constituents in brownfield contexts. To address these issues, recent research proposes to modify the Modular Function Deployment (MFD) with a revised set of drivers and tools. Therefore, this paper presents a modified MFD with value-chain considerations and supportive tools, which is validated in an industrial case. [ABSTRACT FROM AUTHOR]

As the semiconductor industry enters the post‐Moore era, reconfigurability on the device level, that incorporates multifunction in a device unit to realize more complex systems with more compact logic gates, is a promising methodology to extend the development of integrated circuit industry. Here, a reconfigurable carbon nanotube (CNT) barristor is developed on the basis of a Schottky barrier (SB) CNT transistor. The device shows a significant rectifying characteristic and can be reconfigured to a forward rectifying mode or a backward rectifying mode by applying an appropriate gate voltage. The reconfigurability originates from the ambipolar characteristics of the CNT channel, and the rectification behaviors can be attributed to the drain‐induced self‐gating effect. Additional experiments reveal that it is the interfacial charge redistribution that plays the role of an additional gate on the SB near the drain. A gate‐controllable half‐wave rectifier has been fabricated by using the reconfigurable CNT barristor. The CNT barristor brings new functions to CNT electronic devices and also opens up a new methodology for future reconfigurable device design. [ABSTRACT FROM AUTHOR]

Nowadays, the high competitiveness of a company depends on its ability to deal quickly and cost-effectively with the market disruptions. For this reason, companies should have an agile and flexible supply chains to solve problems related to the market fluctuation. In fact, supply chain reconfigurability is the ability to modify their capacity and functionality at the lowest cost. The objective of this article is to assess reconfigurability based on its characteristics (modularity, scalability, integrability, convertibility, diagnosability and customization) using Fuzzy logic. For this purpose, a quantitative evaluation of reconfigurability is proposed. In order to validate our assessment model, a case study is applied to evaluate the degree of reconfigurability after supply chain reconfiguration. [ABSTRACT FROM AUTHOR]

The article presents the results of machine backup designing in reconfigurable industrial processes. The development of manufacturing systems is moving towards intelligent, automated, autonomous, and reconfigurable manufacturing systems. Factories that want to ensure long-term sustainable and competitive manufacturing processes must be designing their processes to respond flexibly to changing changes in customer requirements. The article's introduction characterizes concepts such as cold backup and warm backup machines and indicators relationship as the time between faults and repairs. The materials and methods describes prerequisites as the creation of the product family creation and resource availability with many formulas, simulation models, and its verification for the creation of the family products in the results of this article. The results describes the results from the calculations of the backups and family products of their use in reconfigurable manufacturing systems. The developed methodology for line design uses the principles of reconfiguration in designing configurations regarding advanced approaches in factories. A significant milestone will be the rapid integration of disruptive technologies and approaches into manufacturing systems. The complexity of future manufacturing systems in the Factories of the Future will only be possible with new innovative factory technologies using the digital twin. [ABSTRACT FROM AUTHOR]

Nanophotonics has garnered intensive attention due to its unique capabilities in molding the flow of light in the subwavelength regime. Metasurfaces (MSs) and photonic integrated circuits (PICs) enable the realization of mass-producible, cost-effective, and efficient flat optical components for imaging, sensing, and communications. In order to enable nanophotonics with multipurpose functionalities, chalcogenide phase-change materials (PCMs) have been introduced as a promising platform for tunable and reconfigurable nanophotonic frameworks. Integration of non-volatile chalcogenide PCMs with unique properties such as drastic optical contrasts, fast switching speeds, and long-term stability grants substantial reconfiguration to the more conventional static nanophotonic platforms. In this review, we discuss state-of-the-art developments as well as emerging trends in tunable MSs and PICs using chalcogenide PCMs. We outline the unique material properties, structural transformation, and thermo-optic effects of well-established classes of chalcogenide PCMs. The emerging deep learning-based approaches for the optimization of reconfigurable MSs and the analysis of light-matter interactions are also discussed. The review is concluded by discussing existing challenges in the realization of adjustable nanophotonics and a perspective on the possible developments in this promising area.

The COVID-19 pandemic revealed weaknesses in the global supply chain management. With stock-outs, transportation problems and the bullwhip effect caused by ever-changing demand, it is necessary for decision-makers to review their supply chain configuration. The latter must adapt to new market changes and respond quickly and cost-effectively to customer requirements. In fact, the selection criteria of the most reconfigurable configuration, i.e., the configuration that adapts its structure and its functions to the new market changes, must respond to this problem. The aim of this paper is to conduct a literature review of the criteria and methods for configuration selection in reconfigurable manufacturing systems and reconfigurable supply chains. This study allows to define a roadmap for the configuration selection in reconfigurable supply chains based on the most efficient reconfigurability criteria. We provide new trends to consider in this selection problem. This paper allows managers to choose the most appropriate criteria to implement a reconfigurable supply chain.

Enterprises now face a global, dynamic, and unpredictable economic environment. In response to quick changes of the demand, the production needs to have the ability to adapt rapidly to meet the production requirements. The Reconfigurable Manufacturing System (RMS) paradigm enables such capabilities. However, defining design and reconfiguration rules is highly challenging, as it requires a broad knowledge encompassing the inclusion of technological, production, and economic metrics, as well as an understanding of a reconfiguration strategy, determining the necessary reconfiguration frequency of the system. For now, no global methodology taking all those aspects into account has been proposed. This article presents an original framework for the design, evaluation, and reconfiguration of the Reconfigurable Production System (RPS). New metrics to measure reconfigurability are defined. The design approach consists in three main steps which are individually developed. The selection of the appropriated production system is based on the comparison of reconfigurability and productivity indicators. Finally, the reconfiguration strategy is presented. The methodology is applied on a case study from the automotive industry. [ABSTRACT FROM AUTHOR]

A wide‐band circularly polarized reconfigurable antenna based on a pure water dielectric patch antenna is proposed. By changing the shape of pure water in the plexiglass container symmetrically, the circularly polarized states of the antenna can be switched. And the available bandwidth of right‐hand circular polarization and left‐hand circular polarization remain unchanged. The interface between pure water and air with a great difference in relative dielectric constant is equivalent to an electrical wall. When feed with an L‐shaped metallic probe, the axial ratio of a wide band can be formed, and the impedance bandwidth of antenna can be fully utilized. Under the two circularly polarized states of the antenna, the measured results show that the 3‐dB axial ratio bandwidth is above 24.4% for |S11| < −10 dB, the radiation efficiency is concentrated at 58%–71%, and the maximum gain reaches 3.5 dBi. [ABSTRACT FROM AUTHOR]

• Two clutches allow for predictable transition from moving hub to moving tread. • Linear actuators facilitate transformation from circular track to triangular track. • Prototype testing shows promise for reconfigurable wheel-track. The National Robotics Engineering Center has conceived a novel system that is able to reconfigure from a track to a wheel while in motion. The purpose of this device is to combine the benefits of wheels and tracks to provide performance optimization on a variety of terrain. The first stage of development resulted in two benchtop prototypes: one to test a transition from rotating hub to rotating tread and another to test a constantly-oriented shape transition from circle to triangle. This paper documents the testing of these devices including current draw, temperature change, and braking characteristics. Through experimentation with the first testbed, desired speed was shown to be consistent within +/−6% when transitioning between wheel and track modes at an approximated ground speed between 5 and 35 km/h while transitioning in 5 to 60 seconds. Testing on the second system identified asymmetry in testbed construction and showed consistent loading patterns throughout a 42 mm-change in sprocket position between wheel and track mode while transitioning between 10 and 50 mm/s. The evaluation of these testbeds informed the design of the next process of the reconfigurable wheel-track project, which resulted in a larger prototype capable of propelling a small ground vehicle. [ABSTRACT FROM AUTHOR]

Existing near-data processing (NDP)-powered architectures have demonstrated their strength for some data intensive applications. Data center servers, however, have to serve not only data-intensive but also compute intensive applications. An in-depth understanding of the impact of NDP on various data center applications is still needed. For example, can a compute-intensive application also benefit from NDP? In addition, current NDP techniques focus on maximizing the data processing rate by always utilizing all computing resources at all times. Is this “always running in full gear” strategy consistently beneficial for an application? To answer these questions, we first propose two reconfigurable NDP-powered servers called RANS (Reconfigurable ARM-based NDP Server) and RFNS (Reconfigurable FPGA-based NDP Server). Next, we implement a single engine prototype for each of them based on a conventional data center and then evaluate their effectiveness. Experimental results measured from the two prototypes are then extrapolated to estimate the properties of the two full-size reconfigurable NDP servers. Finally, several new findings are presented. For example, we find that while RANS can only benefit data-intensive applications, RFNS can offer benefits for both data-intensive and compute-intensive applications. Moreover, we find that for certain applications the reconfigurability of RANS/RFNS can deliver noticeable energy efficiency without any performance degradation. [ABSTRACT FROM AUTHOR]

This paper aims to propose a method of optimising the controller reconfiguration (CR) instant for spacecraft control systems with additive actuator faults. Due to severe resource constraints, it is 'expensive' for spacecraft to handle the faults in orbit. To overcome the constraints, we try to reduce the CR cost from a perspective of time management. The basic idea of this method is to propose a reconfigurability evaluation index to quantify the capability of the fault system in maintaining admissible performance by CR measures, and then to derive the mathematical relationship between the reconfigurability index and four crucial instants during the CR process. Based on this, the CR instant is optimised by maximising the reconfigurability index. Finally, the effectiveness of the proposed method is illustrated through an example. The results show that by enhancing the time management efficiency during the CR process, the limited resources can be economised to some extent. [ABSTRACT FROM AUTHOR]

This essay reads Ngũgĩ wa Thiongo's Wizard of the Crow (2006) as an intervention in the ongoing dialogues in African literature. Through the paradigms of 'reciprocality', 'extensibility' and 'reconfigurability', the essay gauges the impacts of dialoguing on the readings of African letters by focusing on ways in which Ngũgĩ reincarnates old concerns of two exemplars of West African literature; Kojo Laing's Major Gentl and the Achimota Wars (1992) and Ayi Kwei Armah's The Beautyful Ones Are Not Yet Born (1968). The article draws on theoretical insights formulated on literary networks to conceptualise the attraction between Armah and Ngũgĩ on one hand and between Laing and Ngũgĩ on the other, with a view to discerning how Ngũgĩ's network novel interrogates and intensifies thematic concerns of the preceding novels. Emphasised throughout the essay is how Ngũgĩ reworks Armah's faecal metaphor and Laing's body transformations in a bid to reflect on the significance of literary networks as both celebrated and productive enterprise that not only circulates interpretations but also regenerates readings of 'network novels'. [ABSTRACT FROM AUTHOR]

This paper proposes a reconfigurable circular microstrip antenna to serve the wireless communication applications that make use frequency bands such as ISM (Industrial Scientific and Medical), WLAN (Wireless Local Area Network), UMTS (Universal Mobile Telecommunications Service). Reconfigurability is achieved with the help of four MEMS (Micro-Electro-Mechanical Systems) switches to change the frequency and radiation properties of the antenna. By choosing either of the two states of each of the MEMS switches, the radius of the circular patch is varied and subsequently the operating resonant frequency. This gives rise to multiple configurations of the antenna to serve for different wireless applications. Defected Ground Structure is employed in this design to lower the resonant frequency and improve the bandwidth. Concentric rings are implemented along with a core circular patch in order to increase the radiating area of the patch in association with the MEMS-based switches to operate in toggle mode of ON and OFF. The concentric rings also helping in obtaining dual-frequency behavior of the antenna and the measured results are showing good agreement with the simulation results. [ABSTRACT FROM AUTHOR]

The computational efficiency is the prime concern of a computation-intensive deep convolutional neural network (CNN). In this Brief, we report an FPGA-based computation-efficient reconfigurable CNN accelerator. It innovates in the utilization of a kernel partition technique to substantially reduce the repeated access to the input feature maps and the kernels. As a result, it balances the ability for parallel computing while consuming less system power. Experimental results prove that the proposed CNN accelerator achieves a peak throughput of 220.0 GOP/s with an energy efficiency of 22.9 GOPs/W at 151.4 frames/s for the AlexNet. It is also reconfigurable to process VGG-16 befitting complex object recognition. [ABSTRACT FROM AUTHOR]

Research on metamaterials shows excellent potential in the field of solar energy harvesting. In recent years, the design of broadband solar metamaterial absorbers (SMAs) has attracted significant interest with the wide application of deep learning methods. This paper proposes a deep neural network (DNN) to realize forward prediction and inverse design of reconfigurable 3D SMAs. In the inverse design, a polarization-insensitive broadband SMA with an absorption bandwidth of 2.7 μm and an average absorption rate of 97.6% with an adjustable bandwidth range of 369 nm is successfully designed. The design of SMAs with different structures is also realized by a transfer learning method to improve the training speed and performance further. Using the transfer learning approach, the training speed of the neural network target model can be accelerated, and its training performance can be improved on small datasets by utilizing the trained neural network source model. Meanwhile, using the trained inverse design target model, a polarization-insensitive broadband SMA was designed with an absorption bandwidth of 2.7 μm, an average absorption of 97.9%, and an adjustable bandwidth range of 141 nm. Finally, we verified the solar energy harvesting capability of the designed broadband SMAs under real-world conditions using air mass (AM) 1.5, and they were calculated to be capable of harvesting the vast majority of the energy. The method is instructive in the design process of SMAs and can be effectively used to explore multifunctional complex nanophotonic devices. • Designing reconfigurable solar absorbers with material selectivity using deep learning methods. • Design of ultra-wideband solar metmaterial absorbers with different shapes through the transfer learning approach. • The designed solar metamaterial absorber has high solar energy harvesting performance. [ABSTRACT FROM AUTHOR]

This work introduces a new Parallel Island Model (PIM) that encompasses the benefits of heterogeneity and algorithmic reconfigurability. The former feature, heterogeneity, means that different islands may execute different evolutionary algorithms. The latter, reconfigurability, means that each island can change the algorithm being executed during the evolutionary process. Allowing such features increases the usual diversity obtained by the communication topologies and migration policies by homogeneous PIMs (HoPIMs). Previous (non-reconfigurable) heterogeneous PIMs (HePIMs) were able to provide competitive solutions regarding the HoPIMs. By adding the reconfiguration capability, PIMs can change dynamically from executing one evolutionary algorithm to another. In this manner, the required diversity and flexibility to outperform HoPIMs and HePIMs is achieved. This paper discusses policies to profit from the feature of reconfigurability on HePIM models and provides an innovative and successful stagnation-based reconfiguration policy. The benefits of the new reconfigurable model are verified using the unsigned reversal distance optimization problem as a case study. [ABSTRACT FROM AUTHOR]

Self-reconfigurable robots have been proposed for a quite long period and in large numbers. However, there are very few systematic methodologies proposed to categorize and evaluate such kinds of robots. In this paper, we put forward a framework for taxonomy and evaluation (TAEV) of self-reconfigurable robots, based on the mechanism reconfigurability and the level of autonomy for reconfiguration. The mechanism reconfigurability of the robots is divided into two types: inter-reconfigurability and intra-reconfigurability which are quantified by the number of configurations and scale respectively. A combination of both the intra- and inter-reconfigurability feature is named as nested-reconfiguration. The levels of autonomy reconfigurability are ranging through different levels from manual teleoperation to fully autonomous systems. The evaluation metrics are introduced to quantify the level of autonomy and the sufficiency of self-reconfigurable robots. Detailed discussions on applications of the proposed framework are presented with real-robot examples.

In this paper, a concept of a reconfigurable chipless radio frequency identification (RFID) sensor tag for detecting solvent vapors/gas in IoT applications was presented. The concept was based on the authors’ previously published rectangular loop structure equipped with a U-folded dipole loaded with a glide-symmetrical interdigital capacitor coated with a thin layer of tetrasulfonated copper phthalocyanine deposited as a sensing layer to improve the sensing capability in the presence of acetone vapor. In order to further maximize the sensitivity of the designed structure to the desired solvent, a circuit for a central frequency adjustment using a radio frequency varactor diode biased with a wireless power transfer (WPT) was designed. By varying the DC bias of the diode, a continuous tunable range of approximately 200 MHz was achieved. The proposed reconfigurable wireless sensor tag was manufactured and the frequency shift was verified by measurement. The proposed external frequency control can be applied to a wide class of electrical resonators.

This paper is divided into two sections, in the first section, a new SIW and a half-mode SIW band-pass filters based on complementary hexagonal metamaterial cells (C-HMCs) are proposed. Firstly, the SIW is analyzed in case of using two C-HMC cells and in the case of using four of these cells. Secondly, the HMSIW tunable BPF is studied and optimized. The size of the half mode is reduced by almost 50%. This filter design has a very high insertion loss about -0.4 dB, and significant transmission bandwidth extending from 5.9 GHz to 6.5 GHz. In the second section of this paper, an electronically reconfigurable SIW band-pass filter is proposed. By implementing two PIN diodes in the gaps of the two C-HMC, the results of turning the diodes ON or OFF individually is a switching in the frequency center, between 5.8 GHz and 6.8 GHz. Also, a dual band with two frequency centers at (5.6 GHz and 7.4 GHz) is achieved by turning both of the diodes ON. In addition, the metamaterial properties of all the proposed filters are investigated and presented in this work.