Biblio

The demand for increasing flexibility use in power systems is stressed by the changing grid utilization. Making use of largely untapped flexibility potential is possible through novel flexibility markets. Different approaches for these markets are being developed and vary considering their handling of transaction schemes and relation of participating entities. This paper delivers the conceptual development of a holistic system architecture for the realization of an interregional flexibility market, which targets a market based congestion management in the transmission and distribution system through trading between system operators and flexibility providers. The framework combines a market mechanism with the required supplements like appropriate control algorithms for emergency situations, cyber-physical system monitoring and cyber-security assessment. The resulting methods are being implemented and verified in a remote-power-hardware-in-the-loop setup coupling a real world low voltage grid with a geographically distant real time simulation using state of the art control system applications with an integration of the aforementioned architecture components.

The resilience assessment of electric and gas networks gains importance due to increasing interdependencies caused by the coupling of gas-fired units. However, the gradually increasing scale of the integrated electricity and gas system (IEGS) poses a significant challenge to current assessment methods. The numerical analysis method is accurate but time-consuming, which may incur a significant computational cost in large-scale IEGS. Therefore, this paper proposes a resilience assessment method based on hetero-functional graph theory for IEGS to balance the accuracy with the computational complexity. In contrast to traditional graph theory, HFGT can effectively depict the coupled systems with inherent heterogeneity and can represent the structure of heterogeneous functional systems in a clear and unambiguous way. In addition, due to the advantages of modelling the system functionality, the effect of line-pack in the gas network on the system resilience is depicted more precisely in this paper. Simulation results on an IEGS with the IEEE 9-bus system and a 7-node gas system verify the effectiveness of the proposed method.

With the ever-increasing use of large-scale IoT networks in different sectors of the industry, it has become critical to realise seamless and secure communication between devices in the network. Realising secure group communication in the IoT requires solving the problem of group-key establishment. In this work, we solve the problem by designing a new lattice-based Key Encapsulation Mechanism (KEM) for resource-constrained devices that enable the distribution of a symmetric key or any other data between all the devices in a given network. This is achieved by coupling multiple private keys to a unique public key. Moreover, we present a proof-of-concept implementation based on the GGH algorithm. The results show it is feasible to use lattice-based cryptography to allow for seamless and secure group communications within a decentralised IoT network. It has been bench-marked against other common post-quantum constructs and proven to be more practical with respect to memory consumption and security, although considerably slower due to lack of optimisation in the implementation.

Intelligent service network under the paradigm of the Internet of Things (IoT) uses sensor and network communication technology to realize the interconnection of everything and real-time communication between devices. Under the background of combat, all kinds of sensor devices and equipment units need to be highly networked to realize interconnection and information sharing, which makes the Internet of Things technology hopeful to be applied in the battlefield to interconnect these entities to form the Internet of Battlefield Things (IoBT). This paper analyzes the related concepts of IoBT, and constructs the IoBT multilayer dependency network model according to the typical characteristics and topology of IoBT, then constructs the weighted super-adjacency matrix according to the coupling weights within and between different layers, and the stability model of IoBT is analyzed and derived. Finally, an example of IoBT network is given to provide a reference for analyzing the stability factors of IoBT network.

With the development of Internet of Things (IoT) technology, the transaction behavior of IoT devices has gradually increased, which also brings the problem of transaction data security and transaction processing efficiency. As one of the research hotspots in the field of data security, blockchain technology has been widely applied in the maintenance of transaction records and the construction of financial payment systems. However, the proportion of microtransactions in the Internet of Things poses challenges to the coupling of blockchain and IoT devices. This paper proposes a three-party scalable architecture based on “IoT device-edge server-blockchain”. In view of the characteristics of micropayment, the verification mechanism of the execution results of the off-chain transaction is designed, and the bridge node is designed in the off-chain architecture, which ensures the finality of the blockchain to the transaction. According to system evaluation, this scalable architecture improves the processing efficiency of micropayments on blockchain, while ensuring its decentration equal to that of blockchain. Compared with other blockchain-based IoT device payment schemes, our architecture is more excellent in activity.

In recent years, the blackout accident shows that the cause of power failure is not only in the power network, but also in the cyber network. Aiming at the problem of cyber network fault Cyber-physical power systems, combined with the structure and functional attributes of cyber network, the comprehensive criticality of information node is defined. By evaluating the vulnerability of ieee39 node system, it is found that the fault of high comprehensive criticality information node will cause greater load loss to the system. The simulation results show that the comprehensive criticality index can effectively identify the key nodes of the cyber network.

Acoustic wave (AW) synthesis methodologies have become popular among AW filter designers because they provide a fast and precise seed to start with the design of AW devices. Nowadays, with the increasing complexity of carrier aggregation, there is a strong necessity to develop synthesis methods more focused on multiport filtering schemes. However, when dealing with multiport filtering functions, numerical accuracy plays an important role to succeed with the synthesis process since polynomial degrees are much higher as compared to the standalone filter case. In addition to polynomial degree, the number set of polynomial coefficients is also an important source of error during the extraction of the circuital elements of the filter. Nonetheless, in this paper is demonstrated that coupling matrix approaches are the best choice when the objective is to synthesize filtering functions with complex roots in their characteristic polynomials, which is the case of the channel polynomials of the multiport device.

A High Overtone Bulk Acoustic Wave Resonator (HBAR) is fabricated with the active material being Ba0.5Sr0.5TiO3 (BST). Owing to its strong electrostrictive property, the BST needs an external dc voltage to yield an electromechanical coupling. The variations in resonances with respect to varying dc fields are noted and analyzed with the aid of an Resonant Spectrum Method (RSM) model. Effective coupling coefficient \$(\textbackslashmathrmK\_\textbackslashmathrme\textbackslashmathrmf\textbackslashmathrmfˆ2(%))\$ in the case of employed MIM based structure is observed and the comparisons are drawn with the corresponding values of the CPC structures. An improvement of 70% in the value of \$\textbackslashmathrmK\_\textbackslashmathrme\textbackslashmathrmf\textbackslashmathrmfˆ2\$(%)at 1.34 GHz is witnessed in MIM structures because of direct access to the bottom electrode of the structure.

The Z machine is a pulsed power generator located at Sandia National Laboratories in Albuquerque, New Mexico. It is capable of producing a \textbackslashtextgreater20 MA current pulse that is directed onto an experimental load. While a diverse array of experiments are conducted on the Z machine, including x-ray production and dynamic materials science experiments, the focus of this presentation are the Magnetic Liner Inertial Fusion (MagLIF) experiments. In these experiments, an axial magnetic field is applied to the load region, where a cylindrical, fuel-filled metal liner is imploded. We explore the effects of this field on the ability to efficiently couple the generator current to the load, and the extent to which this field interrupts the magnetic insulation of the inner-most transmission line. We find that at the present-day applied field values, the effects of the applied field on current coupling are negligible. Estimates of the potential impact on current coupling of the larger applied field values planned for future experiments are also given. Shunted current is measured with B-dot probes and flyer velocimetry techniques. Analytical calculations, 2D particle-in-cell simulations, and experimental measurements will be presented.

Renewable energy resource plays an important role due to increasing energy claim. Power generation by PV technology is one of the fastest growing renewable energy sources due to its clean, economical and sustainable property. Grid integrated PV systems plays an important role in power generation sector. As the energy demand is increasing day by day, the power transfer capability of transmission line is increasing which leads various problems like stability, increase in fault current, congestion etc. To overcome the problem, we can use either FACTS device or battery storage or construct additional lines which is cost effective. This paper deals with grid connected PV system, which functions as PV-STATCOM. Voltage and damping control are used to elevate the power transfer capacity and to achieve regulated voltage within the limits at the point of common coupling (PCC). The studies are performed on SMIB and the simulation is carried out in MATLAB/SIMULINK environment.

Reconfigurability is very popular in advanced highly integrated wireless communication circuits and systems, which is valuable for mitigating spectrum congestion and reducing signal interference. To reduce interference and meet the different wireless standards in different countries, frequency reconfigurable filters are promising. Concurrently, due to the conductor and semiconductor properties of VO2 at different temperatures or pressures, the phase transition characteristics of new material VO2 are applied to reconfigurable filters. This paper mainly discusses the application of phase transition characteristics of VO2 materials in filter design and proposes a frequency reconfigurable microstrip bandpass filter based on VO2 materials, in which the microstrip filter adopts the design form of end coupling. Through theoretical calculation, data analysis, and the establishment of the equivalent model of VO2 phase transition, a related design is proposed. An end-coupled microband bandpass filter centered at a reconfigurable frequency (6 GHz to 6.5 GHz) with fractional bandwidth of 2.8% has been designed, which shows consistent match with the expected ones and verify the validity of the proposed method.

In this paper, we investigated a self-oscillating ring system with variation of the delay time, which demonstrates the phenomenon of laminar chaos. The presence of laminar chaos is demonstrated for various laws of time delay variation - sinusoidal, sawtooth, and triangular. The behavior of coupled systems with laminar chaos and diffusive coupling is investigated. The presence of synchronous behavior is shown.

This paper presents a method to improve the diagnosability of power network under multiple faults. In this paper, the steps of fault diagnosis are as follows: first, constructing finite automata model of the diagnostic system; then, a fault diagnoser model is established through coupling operation and trajectory reasoning mechanism; finally, the diagnosis results are obtained through this model. In this paper, the judgment basis of diagnosability is defined. Then, based on the existing diagnosis results, the information available can be increased by adding sensor devices, to achieve the purpose of diagnosability in the case of multiple faults of the system.

Malware classification helps to understand its purpose and is also an important part of attack detection. And it is also an important part of discovering attacks. Due to continuous innovation and development of artificial intelligence, it is a trend to combine deep learning with malware classification. In this paper, we propose an improved malware image rescaling algorithm (IMIR) based on local mean algorithm. Its main goal of IMIR is to reduce the loss of information from samples during the process of converting binary files to image files. Therefore, we construct a neural network structure based on VGG model, which is suitable for image classification. In the real world, a mass of malware family labels are inaccurate or lacking. To deal with this situation, we propose a novel method to train the deep neural network by Semi-supervised Generative Adversarial Network (SGAN), which only needs a small amount of malware that have accurate labels about families. By integrating SGAN with weak coupling, we can retain the weak links of supervised part and unsupervised part of SGAN. It improves the accuracy of malware classification by making classifiers more independent of discriminators. The results of experimental demonstrate that our model achieves exhibiting favorable performance. The recalls of each family in our data set are all higher than 93.75%.

Under the background of increasingly severe security situation, the new working mode of power mobile internet business anytime and anywhere has greatly increased the complexity of network interaction. At the same time, various means of breaking through the boundary protection and moving laterally are emerging in an endless stream. The existing boundary-based mobility The security protection architecture is difficult to effectively respond to the current complex and diverse network attacks and threats, and faces actual combat challenges. This article first analyzes the security risks faced by the existing power mobile Internet services, and conducts a collaborative analysis of the key points of zero-trust based security protection from multiple perspectives such as users, terminals, and applications; on this basis, from identity security authentication, continuous trust evaluation, and fine-grained access The dimension of control, fine-grained access control based on identity trust, and the design of a zero-trust-based power mobile interconnection business security protection framework to provide theoretical guidance for power mobile business security protection.

In case of wildfire, particles generated in combustion are in complex law of motion under the influence of flame temperature, airflow and lots of electrons and ions. They would distort the space electric field, and lead to gap discharge. This paper develops a multi-physics coupling calculation model of fluid, temperature, electric field and particle movement by combining the rod-plate gap experiment that simulates the wildfire condition. It analyzes the motion state of ash particles in flames, studies the charged particles of different polarity separately, and explores the impact of particle properties on the electric field of gap space by combining the distribution of particles. Results have shown that there are differences in the motion state of charged particles of different polarity, and the electrode will absorb some particles with different charges, while charged particles with the same polarity as the electrode will move away from the electrode in random motion. Particles of different properties (particle size, relative dielectric constant) have different impacts on the electric field of gap space, but they all promote the discharge propagation.

Many autonomous control systems are frequently exposed to attacks, so methods for attack identification are crucial for a safe operation. To preserve the privacy of the subsystems and achieve scalability in large-scale systems, identification algorithms should not require global model knowledge. We analyze a previously presented method for hierarchical attack identification, that is embedded in a distributed control setup for systems of systems with coupled nonlinear dynamics. It is based on the exchange of local sensitivity information and ideas from sparse signal recovery. In this paper, we prove sufficient conditions under which the method is guaranteed to identify all components affected by some unknown attack. Even though a general class of nonlinear dynamic systems is considered, our rigorous theoretical guarantees are applicable to practically relevant examples, which is underlined by numerical experiments with the IEEE 30 bus power system.

In this paper, an acoustic resonator with frequency \textbackslashtextgreater 5 GHz is designed, implemented, and measured with electromechanical coupling exceeding 15% and low temperature dependence compared to conventional Lamb-wave resonators. The acoustic resonator is optimized for the S4 mode Lamb waves in a bi-morph composed of Lithium Niobate and Silicon Dioxide. The resonator optimization is based on adjusting the thickness of different materials in the bimorph to maximize the coupling and minimize temperature dependence simultaneously. The achieved specifications are adequate for 5G sub-6 GHz frequency band n46 in addition to Wi-Fi new bands between 5 and 6 GHz.

We present results from a vibrating mesh nebulizer for which the mesh is a micro-machined silicon membrane perforated with up to a thousand micron-sized, pyramidal holes. Finite element modelling is used to better understand the measured results of the nebulizer when tested in the dry state as well as when loaded with a liquid. In particular, we found that the frequency response of the system is well represented by the superposition of the frequency response of its two main subcomponents: the piezo driving unit and the silicon membrane. As such, the system is found to have resonance peaks for which the complete assembly flexes in addition to peaks that correspond to the flexural resonance modes of the silicon membrane on its own. Similarly, finite element modelling was used to understand differences observed between the frequency response measured on the nebulizer in the dry condition compared to its wet or liquid loaded operation. It was found that coupling between the structural and the acoustic domains shifts the resonance peaks significantly to the left of the frequency plot. In fact, it was found that at the operating frequency of the nebulizer, the system resonates in a (0,3) when the membrane is loaded with a liquid compared with a (0,2) resonance mode when it is operating in the dry state.

This paper reports high frequency surface acoustic wave (SAW) devices developed on Sc doped (30%) AlN on high resistivity Si for demonstrating surface acoustic wave – spin wave coupling. Enhanced Q-factors were found for both propagation modes – Rayleigh (4.7 GHz) and Sezawa (8 GHz). SAW/SW (spin wave) coupling is proven for two-ports SAW structures having a magnetostrictive layer of Ni between the two interdigitated transducers (IDTs). A decrease of 3.42 dB was observed in the amplitude of the transmission parameter, at resonance, when the magnetic field was applied. The angle between the applied magnetic field and the SAW propagation direction is π/4.

Novel acoustic wave networks comprising resonators achieving prescribed coupling are proposed. The design methodology is based on classic network synthesis of doubly- and/or singly-terminated networks. The synthesis of LTE Band 25 contiguous duplexer prototype is performed and its electrical characteristics are presented.

Layer assignment, a major step in global routing of integrated circuits, is usually performed to assign segments of nets to multiple layers. Besides the traditional optimization goals such as overflow and via count, interconnect delay plays an important role in determining chip performance and has been attracting much attention in recent years. Accordingly, in this paper, we propose MiniDelay, a timing-aware layer assignment algorithm to minimize delay for advanced technology nodes, taking both wire congestion and coupling effect into account. MiniDelay consists of the following three key techniques: 1) a non-default-rule routing technique is adopted to reduce the delay of timing critical nets, 2) an effective congestion assessment method is proposed to optimize delay of nets and via count simultaneously, and 3) a net scalpel technique is proposed to further reduce the maximum delay of nets, so that the chip performance can be improved in a global manner. Experimental results on multiple benchmarks confirm that the proposed algorithm leads to lower delay and few vias, while achieving the best solution quality among the existing algorithms with the shortest runtime.

In this paper, a planning method of transportation-power coupled system based on road expansion model is proposed. First of all, based on the Wardrop equilibrium state, the traffic flow is distributed, to build the road expansion model and complete the traffic network modeling. It is assumed that the road charging demand is directly proportional to the road traffic flow, and the charging facilities will cause a certain degree of congestion on the road. This mutual influence relationship to establish a coupling system of transportation network and power network is used for the planning. In the planning method, the decision variables include the location of charging facilities, the setting of energy storage systems and the road expansion scheme. The planning goal is to minimize the investment cost and operation cost. The CPLEX solver is used to solve the mixed integer nonlinear programming problem. Finally, the simulation analysis is carried out to verify the validity and feasibility of the planning method, which can comprehensively consider the road expansion cost and travel time cost, taking a coupled system of 5-node traffic system and IEEE14 node distribution network as example.

Wireless technology is growing at a fast rate to accommodate the expanding user demands. Currently the radio frequency (RF) spectrum is highly congested and more susceptible to signal fratricide and interference. Therefore, full duplexing techniques are required to enhance the access to the spectrum. Simultaneous Transmit and receive systems (STAR), also known as in-band full duplex systems, are gaining higher attention due to their capability to double spectral efficiency. However, successful implementation of STAR systems requires significant isolation between the transmit and receive signals to reduce self-interference (SI) signal. To minimize this self-interference, front-end coupling cancellation circuits are employed in STAR system. In this paper, an RF coupling suppression circuit is presented based on a hybrid finite impulse response filter (FIR) and resonator architecture. Notably, this newly developed FIR-resonator circuit achieves \textbackslashtextgreater30dB cancellation across a \textbackslashtextgreater1.5:1 bandwidth.

This paper presents a study and analysis of flux linkage performance on 12/8 pole doubly salient permanent magnet machine in square envelope conventional. Analyzed model was using a finite element method. The investigated model was constructed by changing the size of the structure as the main parameters of the speed 500 rpm, PM coercivity 910 kA/m, PM remanence 1.2 T, copper loss 30 W, turns per coil 45, and stator side length 100 mm. The study and analysis of flux linkage, induced voltage, and torque are also included in this paper.