Biblio

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2021-01-18
Ergün, S., Tanrıseven, S..  2020.  Random Number Generator Based on Skew-tent Map and Chaotic Sampling. 2020 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS). :224–227.
In this paper a novel random number generator is introduced and it is based on the Skew-tent discrete-time chaotic map. The RNG presented in this paper is made using the discrete-time chaotic map and chaotic sampling of regular waveform method together to increase the throughput and statistical quality of the output sequence. An explanation of the arithmetic model for the proposed design is given in this paper with an algebra confirmation for the generated bit stream that shows how it passes the primary four tests of the FIPS-140-2 test suit successfully. Finally the bit stream resulting from the hardware implementation of the circuit in a similar method has been confirmed to pass all NIST-800-22 test with no post processing. A presentation of the experimentally obtained results is given therefor proving the the circuit’s usefulness. The proposed RNG can be built with the integrated circuit.
2020-11-30
Pan, T., Xu, C., Lv, J., Shi, Q., Li, Q., Jia, C., Huang, T., Lin, X..  2019.  LD-ICN: Towards Latency Deterministic Information-Centric Networking. 2019 IEEE 21st International Conference on High Performance Computing and Communications; IEEE 17th International Conference on Smart City; IEEE 5th International Conference on Data Science and Systems (HPCC/SmartCity/DSS). :973–980.
Deterministic latency is the key challenge that must be addressed in numerous 5G applications such as AR/VR. However, it is difficult to make customized end-to-end resource reservation across multiple ISPs using IP-based QoS mechanisms. Information-Centric Networking (ICN) provides scalable and efficient content distribution at the Internet scale due to its in-network caching and native multicast capabilities, and the deterministic latency can promisingly be guaranteed by caching the relevant content objects in appropriate locations. Existing proposals formulate the ICN cache placement problem into numerous theoretical models. However, the underlying mechanisms to support such cache coordination are not discussed in detail. Especially, how to efficiently make cache reservation, how to avoid route oscillation when content cache is updated and how to conduct the real-time latency measurement? In this work, we propose Latency Deterministic Information-Centric Networking (LD-ICN). LD-ICN relies on source routing-based latency telemetry and leverages an on-path caching technique to avoid frequent route oscillation while still achieve the optimal cache placement under the SDN architecture. Extensive evaluation shows that under LD-ICN, 90.04% of the content requests are satisfied within the hard latency requirements.
2021-01-22
Zaher, A. A., Hussain, G. Amjad.  2019.  Chaos-based Cryptography for Transmitting Multimedia Data over Public Channels. 2019 7th International Conference on Information and Communication Technology (CoICT). :1–6.

This paper explores using chaos-based cryptography for transmitting multimedia data, mainly speech and voice messages, over public communication channels, such as the internet. The secret message to be transmitted is first converted into a one-dimensional time series, that can be cast in a digital/binary format. The main feature of the proposed technique is mapping the two levels of every corresponding bit of the time series into different multiple chaotic orbits, using a simple encryption function. This one-to-many mapping robustifies the encryption technique and makes it resilient to crypto-analysis methods that rely on associating the energy level of the signal into two binary levels, using return map attacks. A chaotic nonautonomous Duffing oscillator is chosen to implement the suggested technique, using three different parameters that are assumed unknown at the receiver side. Synchronization between the transmitter and the receiver and reconstructing the secret message, at the receiver side, is done using a Lyapunov-based adaptive technique. Achieving stable operation, tuning the required control gains, as well as effective utilization of the bandwidth of the public communication channel are investigated. Two different case studies are presented; the first one deals with text that can be expressed as 8-bit ASCII code, while the second one corresponds to an analog acoustic signal that corresponds to the voice associated with pronouncing a short sentence. Advantages and limitation of the proposed technique are highlighted, while suggesting extensions to other multimedia signals, along with their required additional computational effort.

2019-11-25
Zaher, Ashraf A., Amjad Hussain, G..  2019.  Chaos-based Cryptography for Transmitting Multimedia Data over Public Channels. 2019 7th International Conference on Information and Communication Technology (ICoICT). :1–6.

This paper explores using chaos-based cryptography for transmitting multimedia data, mainly speech and voice messages, over public communication channels, such as the internet. The secret message to be transmitted is first converted into a one-dimensional time series, that can be cast in a digital/binary format. The main feature of the proposed technique is mapping the two levels of every corresponding bit of the time series into different multiple chaotic orbits, using a simple encryption function. This one-to-many mapping robustifies the encryption technique and makes it resilient to crypto-analysis methods that rely on associating the energy level of the signal into two binary levels, using return map attacks. A chaotic nonautonomous Duffing oscillator is chosen to implement the suggested technique, using three different parameters that are assumed unknown at the receiver side. Synchronization between the transmitter and the receiver and reconstructing the secret message, at the receiver side, is done using a Lyapunov-based adaptive technique. Achieving stable operation, tuning the required control gains, as well as effective utilization of the bandwidth of the public communication channel are investigated. Two different case studies are presented; the first one deals with text that can be expressed as 8-bit ASCII code, while the second one corresponds to an analog acoustic signal that corresponds to the voice associated with pronouncing a short sentence. Advantages and limitation of the proposed technique are highlighted, while suggesting extensions to other multimedia signals, along with their required additional computational effort.

2020-04-24
Balijabudda, Venkata Sreekanth, Thapar, Dhruv, Santikellur, Pranesh, Chakraborty, Rajat Subhra, Chakrabarti, Indrajit.  2019.  Design of a Chaotic Oscillator based Model Building Attack Resistant Arbiter PUF. 2019 Asian Hardware Oriented Security and Trust Symposium (AsianHOST). :1—6.

Physical Unclonable Functions (PUFs) are vulnerable to various modelling attacks. The chaotic behaviour of oscillating systems can be leveraged to improve their security against these attacks. We have integrated an Arbiter PUF implemented on a FPGA with Chua's oscillator circuit to obtain robust final responses. These responses are tested against conventional Machine Learning and Deep Learning attacks for verifying security of the design. It has been found that such a design is robust with prediction accuracy of nearly 50%. Moreover, the quality of the PUF architecture is evaluated for uniformity and uniqueness metrics and Monte Carlo analysis at varying temperatures is performed for determining reliability.

Bellec, Q., le Claire, J.C., Benkhoris, M.F., Coulibaly, P..  2019.  Investigation of time delay effects on the current in a power converter regulated by Phase-Shift Self-Oscillating Current Controller. 2019 21st European Conference on Power Electronics and Applications (EPE '19 ECCE Europe). :P.1–P.10.

This paper deals with effects of current sensor bandwidth and time delays in a system controlled by a Phase-Shift Self-Oscillating Current Controller (PSSOCC). The robustness of this current controller has been proved in former works showing its good performances in a large range of applications including AC/DC and DC/AC converters, power factor correction, active filters, isolation amplifiers and motor control. As switching frequencies can be upper than 30kHz, time delays and bandwidth limitations cannot be neglected in comparison with former works on this robust current controller. Thus, several models are proposed in this paper to analyze system behaviours. Those models permit to find analytical expressions binding maximum oscillation frequency with time delay and/or additional filter parameters. Through current spectrums analysis, quality of analytical expressions is proved for each model presented in this work. An experimental approach shows that every element of the electronic board having a low-pass effect or delaying command signals need to be included in the model in order to have a perfect match between calculations, simulations and practical results.

2020-11-20
Zhu, S., Chen, H., Xi, W., Chen, M., Fan, L., Feng, D..  2019.  A Worst-Case Entropy Estimation of Oscillator-Based Entropy Sources: When the Adversaries Have Access to the History Outputs. 2019 18th IEEE International Conference On Trust, Security And Privacy In Computing And Communications/13th IEEE International Conference On Big Data Science And Engineering (TrustCom/BigDataSE). :152—159.
Entropy sources are designed to provide unpredictable random numbers for cryptographic systems. As an assessment of the sources, Shannon entropy is usually adopted to quantitatively measure the unpredictability of the outputs. In several related works about the entropy evaluation of ring oscillator-based (RO-based) entropy sources, authors evaluated the unpredictability with the average conditional Shannon entropy (ACE) of the source, moreover provided a lower bound of the ACE (LBoACE). However, in this paper, we have demonstrated that when the adversaries have access to the history outputs of the entropy source, for example, by some intrusive attacks, the LBoACE may overestimate the actual unpredictability of the next output for the adversaries. In this situation, we suggest to adopt the specific conditional Shannon entropy (SCE) which exactly measures the unpredictability of the future output with the knowledge of previous output sequences and so is more consistent with the reality than the ACE. In particular, to be conservative, we propose to take the lower bound of the SCE (LBoSCE) as an estimation of the worst-case entropy of the sources. We put forward a detailed method to estimate this worst-case entropy of RO-based entropy sources, which we have also verified by experiment on an FPGA device. We recommend to adopt this method to provide a conservative assessment of the unpredictability when the entropy source works in a vulnerable environment and the adversaries might obtain the previous outputs.
2020-04-24
Bertram, Jon, Tanwear, Asfand, Rodriguez, Aurelio, Paterson, Gary, McVitie, Stephen, Heidari, Hadi.  2019.  Spin-Hall Nano-Oscillator Simulations. 2019 IEEE SENSORS. :1—4.

A spin-Hall nano-oscillator (SHNO) is a type of spintronic oscillator that shows promising performance as a nanoscale microwave source and for neuromorphic computing applications. Within such nanodevices, a non-ferromagnetic layer in the presence of an external magnetic field and a DC bias current generates an oscillating microwave voltage. For developing optimal nano-oscillators, accurate simulations of the device's complex behaviour are required before fabrication. This work simulates the key behaviour of a nanoconstriction SHNO as the applied DC bias current is varied. The current density and Oersted field of the device have been presented, the magnetisation oscillations have been clearly visualised in three dimensions and the spatial distribution of the active mode determined. These simulations allow designers a greater understanding and characterisation of the device's behaviour while also providing a means of comparison when experimental resultsO are generated.

2020-11-09
Hazari, N. A., Alsulami, F., Niamat, M..  2018.  FPGA IP Obfuscation Using Ring Oscillator Physical Unclonable Function. NAECON 2018 - IEEE National Aerospace and Electronics Conference. :105–108.
IP piracy, reverse engineering, and tampering with FPGA based IP is increasing over time. ROPUF based IP obfuscation can provide a feasible solution. In this paper, a novel approach of FPGA IP obfuscation is implemented using Ring Oscillator based Physical Unclonable Function (ROPUF) and random logic gates. This approach provides a lock and key mechanism as well as authentication of FPGA based designs to protect from security threats. Using the Xilinx ISE design tools and ISCAS 89 benchmarks we have designed a secure FPGA based IP protection scheme with an average of 15% area and 10% of power overhead.
2020-04-24
Bahman Soltani, Hooman, Abiri, Habibollah.  2018.  Criteria for Determining Maximum Theoretical Oscillating Frequency of Extended Interaction Oscillators for Terahertz Applications. IEEE Transactions on Electron Devices. 65:1564—1571.

Extended interaction oscillators (EIOs) are high-frequency vacuum-electronic sources, capable to generate millimeter-wave to terahertz (THz) radiations. They are considered to be potential sources of high-power submillimeter wavelengths. Different slow-wave structures and beam geometries are used for EIOs. This paper presents a quantitative figure of merit, the critical unloaded oscillating frequency (fcr) for any specific geometry of EIO. This figure is calculated and tested for 2π standing-wave modes (a common mode for EIOs) of two different slowwave structures (SWSs), one double-ridge SWS driven by a sheet electron beam and one ring-loaded waveguide driven by a cylindrical beam. The calculated fcrs are compared with particle-in-cell (PIC) results, showing an acceptable agreement. The derived fcr is calculated three to four orders of magnitude faster than the PIC solver. Generality of the method, its clear physical interpretation and computational rapidity, makes it a convenient approach to evaluate the high-frequency behavior of any specified EIO geometry. This allows to investigate the changes in geometry to attain higher frequencies at THz spectrum.

Makhoul, Rawad, Maynard, Xavier, Perichon, Pierre, Frey, David, Jeannin, Pierre-Olivier, Lembeye, Yves.  2018.  A Novel Self Oscillating Class Phi2 Inverter Topology. 2018 2nd European Conference on Electrical Engineering and Computer Science (EECS). :7—10.

The class φ2 is a single transistor, fast transient inverter topology often associated with power conversion at very high frequency (VHF: 30MHz-300MHz). At VHF, gate drivers available on the market fail to provide the adequate transistor switching signal. Hence, there is a need for new power topologies that do no make use of gate drivers but are still suitable for power conversion at VHF. In This paper, we introduce a new class φ;2 topology that incorporates an oscillator, which takes the drain signal through a feedback circuit in order to force the transistor switching. A design methodology is provided and a 1MHz 20V input prototype is built in order to validate the topology behaviour.

2020-12-02
Tsurumi, R., Morita, M., Obata, H., Takano, C., Ishida, K..  2018.  Throughput Control Method Between Different TCP Variants Based on SP-MAC Over WLAN. 2018 IEEE International Conference on Consumer Electronics-Taiwan (ICCE-TW). :1—2.

We have proposed the Media Access Control method based on the Synchronization Phenomena of coupled oscillators (SP-MAC) to improve a total throughput of wireless terminals connected to a Access Point. SP-MAC can avoid the collision of data frames that occur by applying Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) based on IEEE 802.11 in Wireless local area networks (WLAN). Furthermore, a new throughput guarantee control method based on SP-MAC has been proposed. This method enable each terminal not only to avoid the collision of frames but also to obtain the requested throughput by adjusting the parameters of SP-MAC. In this paper, we propose a new throughput control method that realizes the fairness among groups of terminals that use the different TCP versions, by taking the advantage of our method that is able to change acquired throughput by adjusting parameters. Moreover, we confirm the effectiveness of the proposed method by the simulation evaluation.

2018-02-21
Li, T., Wu, L., Zhang, X., Wu, X., Zhou, J., Wang, X..  2017.  A novel transition effect ring oscillator based true random number generator for a security SoC. 2017 International Conference on Electron Devices and Solid-State Circuits (EDSSC). :1–2.

The transition effect ring oscillator (TERO) based true random number generator (TRNG) was proposed by Varchola and Drutarovsky in 2010. There were several stochastic models for this advanced TRNG based on ring oscillator. This paper proposed an improved TERO based TRNG and implements both on Altera Cyclone series FPGA platform and on a 0.13um CMOS ASIC process. FPGA experimental results show that this balanced TERO TRNG is in good performance as the experimental data results past the national institute of standards and technology (NIST) test in 1M bit/s. The TRNG is feasible for a security SoC.

2017-12-20
Adiyatullin, A. F., Anderson, M. D., Flayac, H., Portella-Oberli, M. T., Jabeen, F., Ouellet-Plamondon, C., Sallen, G. C., Deveaud, B..  2017.  Periodic squeezing in a polariton Josephson junction. 2017 Conference on Lasers and Electro-Optics Europe European Quantum Electronics Conference (CLEO/Europe-EQEC). :1–1.

Microcavity polaritons are a hybrid photonic system that arises from the strong coupling of confined photons to quantum-well excitons. Due to their light-matter nature, polaritons possess a Kerr-like nonlinearity while being easily accessible by standard optical means. The ability to engineer confinement potentials in microcavities makes polaritons a very convenient system to study spatially localized bosonic populations, which might have great potential for the creation of novel photonic devices. Careful engineering of this system is predicted to induce Gaussian squeezing, a phenomenon that lies at a heart of the so-called unconventional photon blockade associated with single photon emission. This paper reveals a manifestation of the predicted squeezing by measuring the ultrafast time-dependent second-order correlation function g(2)(0) by means of a streak-camera acting as a single photon detector. The light emitted by the microcavity oscillates between Poissonian and super-Poissonian in phase with the Josephson dynamics. This behavior is remarkably well explained by quantum simulations, which predict such dynamical evolution of the squeezing parameters. The paper shows that a crucial prerequisite for squeezing is presence of a weak, but non-zero nonlinearity. Results open the way towards generation of nonclassical light in solid-state systems possessing a single particle nonlinearity like microwave Josephson junctions or silicon-on-chip resonators.

2018-05-17
J. C. Gallagher, E. T. Matson, J. Goppert.  2017.  A Provisional Approach to Maintaining Verification and Validation Capability in Self-Adapting Robots. 2017 First IEEE International Conference on Robotic Computing (IRC). :382-388.

Cyber Physical Systems (CPS) are composed of multiple physical and computing components that are deeply intertwined, operate on differing spatial and temporal scales, and interact with one another in fluid, context dependent, manners. Cyber Physical Systems often include smart components that use local adaptation to improve whole system performance or to provide damage response. Evolvable and Adaptive Hardware (EAH) components, at least conceptually, are often represented as an enabling technology for such smart components. This paper will outline one approach to applying CPS thinking to better address a growing need to address Verification and Validation (V&V) questions related to the use of EAH smart components. It will argue that, perhaps fortuitously, the very adaptations EAH smart components employ for performance improvement may also be employed to maintain V&V capability.

2018-05-24
Rajagopalan, S., Rethinam, S., Deepika, A. N., Priyadarshini, A., Jyothirmai, M., Rengarajan, A..  2017.  Design of Boolean Chaotic Oscillator Using CMOS Technology for True Random Number Generation. 2017 International Conference on Microelectronic Devices, Circuits and Systems (ICMDCS). :1–6.

True random numbers have a fair role in modern digital transactions. In order to achieve secured authentication, true random numbers are generated as security keys which are highly unpredictable and non-repetitive. True random number generators are used mainly in the field of cryptography to generate random cryptographic keys for secure data transmission. The proposed work aims at the generation of true random numbers based on CMOS Boolean Chaotic Oscillator. As a part of this work, ASIC approach of CMOS Boolean Chaotic Oscillator is modelled and simulated using Cadence Virtuoso tool based on 45nm CMOS technology. Besides, prototype model has been implemented with circuit components and analysed using NI ELVIS platform. The strength of the generated random numbers was ensured by NIST (National Institute of Standards and Technology) Test Suite and ASIC approach was validated through various parameters by performing various analyses such as frequency, delay and power.

2018-05-17
M. Sam, S. Boddhu, J. Gallagher.  2017.  A dynamic search space approach to improving learning on a simulated Flapping Wing Micro Air Vehicle. 2017 IEEE Congress on Evolutionary Computation (CEC). :629-635.

Those employing Evolutionary Algorithms (EA) are constantly challenged to engineer candidate solution representations that balance expressive power (I.E. can a wide variety of potentially useful solutions be represented?) and meta-heuristic search support (I.E. does the representation support fast acquisition and subsequent fine-tuning of adequate solution candidates). In previous work with a simulated insect-like Flapping-Wing Micro Air Vehicle (FW-MAV), an evolutionary algorithm was employed to blend descriptions of wing flapping patterns to restore correct flight behavior after physical damage to one or both of the wings. Some preliminary work had been done to reduce the overall size of the search space as a means of improving time required to acquire a solution. This of course would likely sacrifice breadth of solutions types and potential expressive power of the representation. In this work, we focus on methods to improve performance by augmenting EA search to dynamically restrict and open access to the whole space to improve solution acquisition time without sacrificing expressive power of the representation. This paper will describe some potential restriction/access control methods and provide preliminary experimental results on the efficacy of these methods in the context of adapting FW-MAV wing gaits.

2018-01-23
Zhmud, V., Dimitrov, L., Taichenachev, A..  2017.  Model study of automatic and automated control of hysteretic object. 2017 International Siberian Conference on Control and Communications (SIBCON). :1–5.

This paper presents the results of research and simulation of feature automated control of a hysteretic object and the difference between automated control and automatic control. The main feature of automatic control is in the fact that the control loop contains human being as a regulator with its limited response speed. The human reaction can be described as integrating link. The hysteretic object characteristic is switching from one state to another. This is followed by a transient process from one to another characteristic. For this reason, it is very difficult to keep the object in a desired state. Automatic operation ensures fast switching of the feedback signal that produces such a mode, which in many ways is similar to the sliding mode. In the sliding mode control signal abruptly switches from maximum to minimum and vice versa. The average value provides the necessary action to the object. Theoretical analysis and simulation show that the use of the maximum value of the control signal is not required. It is sufficient that the switching oscillation amplitude is such that the output signal varies with the movement of the object along both branches with hysteretic characteristics in the fastest cycle. The average output value in this case corresponds to the prescribed value of the control task. With automated control, the human response can be approximately modeled by integrating regulator. In this case the amplitude fluctuation could be excessively high and the frequency could be excessively low. The simulation showed that creating an artificial additional fluctuation in the control signal makes possible to provide a reduction in the amplitude and the resulting increase in the frequency of oscillation near to the prescribed value. This should be evaluated as a way to improve the quality of automated control with the helps of human being. The paper presents some practical examples of the examined method.

2018-06-11
Coustans, M., Terrier, C., Eberhardt, T., Salgado, S., Cherkaoui, A., Fesquet, L..  2017.  A subthreshold 30pJ/bit self-timed ring based true random number generator for internet of everything. 2017 IEEE SOI-3D-Subthreshold Microelectronics Technology Unified Conference (S3S). :1–3.

This paper presents a true random number generator that exploits the subthreshold properties of jitter of events propagating in a self-timed ring and jitter of events propagating in an inverter based ring oscillator. Design was implemented in 180nm CMOS flash process. Devices provide high quality random bit sequences passing FIPS 140-2 and NIST SP 800-22 statistical tests which guaranty uniform distribution and unpredictability thanks to the physics based entropy source.

2018-01-23
Abtioglu, E., Yeniçeri, R., Gövem, B., Göncü, E., Yalçin, M. E., Saldamli, G..  2017.  Partially Reconfigurable IP Protection System with Ring Oscillator Based Physically Unclonable Functions. 2017 New Generation of CAS (NGCAS). :65–68.

The size of counterfeiting activities is increasing day by day. These activities are encountered especially in electronics market. In this paper, a countermeasure against counterfeiting on intellectual properties (IP) on Field-Programmable Gate Arrays (FPGA) is proposed. FPGA vendors provide bitstream ciphering as an IP security solution such as battery-backed or non-volatile FPGAs. However, these solutions are secure as long as they can keep decryption key away from third parties. Key storage and key transfer over unsecure channels expose risks for these solutions. In this work, physical unclonable functions (PUFs) have been used for key generation. Generating a key from a circuit in the device solves key transfer problem. Proposed system goes through different phases when it operates. Therefore, partial reconfiguration feature of FPGAs is essential for feasibility of proposed system.

2018-05-17
J. C. Gallagher, M. Sam, S. Boddhu, E. T. Matson, G. Greenwood.  2016.  Drag force fault extension to evolutionary model consistency checking for a flapping-wing micro air vehicle. 2016 IEEE Congress on Evolutionary Computation (CEC). :3961-3968.

Previously, we introduced Evolutionary Model Consistency Checking (EMCC) as an adjunct to Evolvable and Adaptive Hardware (EAH) methods. The core idea was to dual-purpose objective function evaluations to simultaneously enable EA search of hardware configurations while simultaneously enabling a model-based inference of the nature of the damage that necessitated the hardware adaptation. We demonstrated the efficacy of this method by modifying a pair of EAH oscillators inside a simulated Flapping-Wing Micro Air Vehicle (FW-MAV). In that work, we were able to show that one could, while online in normal service, evolve wing gait patterns that corrected altitude control errors cause by mechanical wing damage while simultaneously determining, with high precision, what the wing lift force deficits that necessitated the adaptation. In this work, we extend the method to be able to also determine wing drag force deficits. Further, we infer the now extended set of four unknown damage estimates without substantially increasing the number of objective function evaluations required. In this paper we will provide the outlines of a formal derivation of the new inference method plus experimental validation of efficacy. The paper will conclude with commentary on several practical issues, including better containment of estimation error by introducing more in-flight learning trials and why one might argue that these techniques could eventually be used on a true free-flying flapping wing vehicle.

2017-03-08
Yan, Y., Bao, W., Zhang, H., Liu, B., Xin, L..  2015.  Study of the disturbance propagation in the discrete model of power networks. 2015 5th International Conference on Electric Utility Deregulation and Restructuring and Power Technologies (DRPT). :2436–2441.

The study of the characteristics of disturbance propagation in the interconnected power networks is of great importance to control the spreading of disturbance and improve the security level of power systems. In this paper, the characteristics of disturbance propagation in a one-dimensional chained power network are studied from the electromechanical wave point of view. The electromechanical wave equation is built based on the discrete inertia model of power networks. The wave transfer function which can describe the variations of amplitude and the phase is derived. Then, the propagation characteristics of different frequency disturbances are analyzed. The corner frequency of the discrete inertia model is proposed. Furthermore, the frequency dispersion and local oscillation are considered and their relationships with the corner frequency are revealed as well. Computer simulations for a 50 generators chained network are carried out to verify the propagation characteristics of disturbances with different frequencies.

2018-05-17
M. Sam, S. K. Boddhu, K. E. Duncan, J. C. Gallagher.  2014.  Evolutionary strategy approach for improved in-flight control learning in a simulated Insect-Scale Flapping-Wing Micro Air Vehicle. 2014 IEEE International Conference on Evolvable Systems. :211-218.

Insect-Scale Flapping-Wing Micro-Air Vehicles (FW-MAVs), can be particularly sensitive to control deficits caused by ongoing wing damage and degradation. Since any such degradation could occur during flight and likely in ways difficult to predict apriori, any automated methods to apply correction would also need to be applied in-flight. Previous work has demonstrated effective recovery of correct flight behavior via online (in service) evolutionary algorithm based learning of new wing-level oscillation patterns. In those works, Evolutionary Algorithms (EAs) were used to continuously adapt wing motion patterns to restore the force generation expected by the flight controller. Due to the requirements for online learning and fast recovery of correct flight behavior, the choice of EA is critical. The work described in this paper replaces previously used oscillator learning algorithms with an Evolution Strategy (ES), an EA variant never previously tested for this application. This paper will demonstrate that this approach is both more effective and faster than previously employed methods. The paper will conclude with a discussion of future applications of the technique within this problem domain.

K. E. Duncan, S. K. Boddhu, M. Sam, J. C. Gallagher.  2014.  Islands of fitness compact genetic algorithm for rapid in-flight control learning in a Flapping-Wing Micro Air Vehicle: A search space reduction approach. 2014 IEEE International Conference on Evolvable Systems. :219-226.

On-going effective control of insect-scale Flapping-Wing Micro Air Vehicles could be significantly advantaged by active in-flight control adaptation. Previous work demonstrated that in simulated vehicles with wing membrane damage, in-flight recovery of effective vehicle attitude and vehicle position control precision via use of an in-flight adaptive learning oscillator was possible. A significant portion of the most recent approaches to this problem employed an island-of-fitness compact genetic algorithm (ICGA) for oscillator learning. The work presented in this paper provides the details of a domain specific search space reduction approach implemented with existing ICGA and its effect on the in-flight learning time. Further, it will be demonstrated that the proposed search space reduction methodology is effective in producing an error correcting oscillator configuration rapidly, online, while the vehicle is in normal service. The paper will present specific simulation results demonstrating the value of the search space reduction and discussion of future applications of the technique to this problem domain.

2015-05-04
Cherkaoui, A., Bossuet, L., Seitz, L., Selander, G., Borgaonkar, R..  2014.  New paradigms for access control in constrained environments. Reconfigurable and Communication-Centric Systems-on-Chip (ReCoSoC), 2014 9th International Symposium on. :1-4.

The Internet of Things (IoT) is here, more than 10 billion units are already connected and five times more devices are expected to be deployed in the next five years. Technological standarization and the management and fostering of rapid innovation by governments are among the main challenges of the IoT. However, security and privacy are the key to make the IoT reliable and trusted. Security mechanisms for the IoT should provide features such as scalability, interoperability and lightness. This paper addresses authentication and access control in the frame of the IoT. It presents Physical Unclonable Functions (PUF), which can provide cheap, secure, tamper-proof secret keys to authentify constrained M2M devices. To be successfully used in the IoT context, this technology needs to be embedded in a standardized identity and access management framework. On the other hand, Embedded Subscriber Identity Module (eSIM) can provide cellular connectivity with scalability, interoperability and standard compliant security protocols. The paper discusses an authorization scheme for a constrained resource server taking advantage of PUF and eSIM features. Concrete IoT uses cases are discussed (SCADA and building automation).