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The recent blackout in UK indicates that the adequacy of flexible resources is a significant factor for the stability of bulk energy system under the high integration of renewable energy. This paper proposes a planning model that incorporates various flexible resources into uncertain energy system and hence optimizes the unites' capacity and dispatch schedule. Based on Bash Game theory, the optimization capacity and dispatch schedule problems are formulated accordingly. Without setting the capacity configuration variable, the model initiatively considers the stochastic nature of RE at the planning stage. To simplify the complexity of the planning model, the problem is relaxation decoupled into two convex sub-issues, which achieves dramatic improvements in solution time. The novel model has been simulated both under IEEE-39 system and IEEE-118 system and hence the model's performance has been tested. Under the proposed model, the energy system can operate in a secure, economic and optimal state. Results demonstrate the effectiveness of the proposed method in applying to the future energy system.

As an important branch of the Internet of Things (IoT), the Internet of Vehicles (IoV) has attracted extensive attention in the research field. To deeply study the IoV and build a vehicle spatiotemporal interaction network, it is necessary to use the trajectory data of private cars. However, due to privacy and security protection policies and other reasons, the data set of private cars cannot be obtained, which hinders the research on the social attributes of vehicles in the IoV. Most of the previous work generated the same type of data, and how to generate private car data sets from various existing data sets is a huge challenge. In this paper, we propose a tri-layer framework to solve this problem. First, we propose a novel region division scheme that considers detailed inter-region relations connected by traffic flux. Second, a new spatial-temporal interaction model is developed to estimate the traffic flow between two regions. Third, we devise an evaluation pipeline to validate generation results from microscopic and macroscopic perspectives. Qualitative and quantitative results demonstrate that the data generated in heavy density scenarios can provide strong data support for downstream IoV and mobility research tasks. [ABSTRACT FROM AUTHOR]

A fully metallic leaky-wave antenna (LWA) with enhanced scanning rate is presented. The leaky waveguide is implemented in groove gap waveguide technology and is periodically loaded to produce backward radiation. Furthermore, glide-symmetric pins are placed inside the leaky waveguide to increase the dispersion. A parallel-plate waveguide metasurface prism lens is used to disperse the backward radiation and increase the scanning rate of the LWA. The designed antenna can steer the radiation from −26° to 26° from 27 to 35 GHz, and an average total efficiency of 74% is achieved. A prototype of the designed antenna is manufactured, and measurements corroborate the simulated results. The proposed concept is applicable to other frequency-scanning antennas and can be used to increase the scanning rate in radar and imaging systems. [ABSTRACT FROM AUTHOR]

A systematic and efficient multimodal transfer-matrix approach is proposed for the comprehensive Bloch analysis of general 1-D/2-D/3-D periodic structures. We provide a linearization procedure for transforming the original nonlinear eigenvalue problem associated with 2-D/3-D structures to a standard one that can easily be solved without the need of a zero-searching algorithm in the complex plane. The proposed approach has been validated with bounded/open structures with complex geometries and/or inhomogeneous lossless/lossy materials. It demonstrates a significantly reduced computational time and leverages the strengths of full-wave simulators to deal with general problems and ad hoc quasi-analytical methods to give a fundamental understanding of the behavior of the structure. Also, it allows for an accurate evaluation of the imaginary part of the wavenumber, which offers information of material dissipation, stopband rejection, leakage, and complex modes. [ABSTRACT FROM AUTHOR]

This article summarizes the recently discovered opportunities of geodesic lenses for producing high-performing antennas for 5G/6G communications. First, we explain the operation of these lenses based on Geometrical Optics with rays that follow “the shortest optical path” on the geodesic surface. Also, we explain the connection between geodesic lenses and rotationally symmetric graded-index lenses. Generally, geodesic lenses can be implemented without the need of dielectric materials, resulting in very efficient devices constructed with a fully-metallic configuration. When combined with a feeding network and a radiating transition, such as a flare or a leaky wave, they can produce a multiple-beam lens antenna, of interest for applications requiring one-dimensional (e.g., azimuthal) coverage diversity such as in cell tower communication systems. Prototypes of these antennas have been recently tested, demonstrating remarkable performance in the Ka-band, part of which is considered for 5G. At high operational frequencies allocated for 5G/6G, geodesic lenses offer an opportunity to produce cost-effective antenna solutions with high directivity, high efficiency and spatial diversity through multiple beams. [ABSTRACT FROM AUTHOR]

This paper presents a new, effective, and facile method to enhance the humidity sensitivity of lignin-based QCM sensor through fringing field effect. The biodegradable and renewable lignin was deposited on the surface of metal electrode as humidity-sensitive material. The microscopic morphology, hydrophilic groups, and water contact angle of the lignin sample were characterized. Then, the humidity-sensing performances of the lignin-based QCM sensors with symmetric and ringed electrode configurations were investigated through the oscillating circuit method. The experimental results showed that the humidity sensitivity of the ringed electrode QCM (61 Hz/%RH) is higher than that of the symmetric electrode QCM in the range of 11.3%-97.3% RH. Moreover, the ringed electrode QCM based on lignin exhibited low humidity hysteresis (~6.2% RH), good logarithmic relationship, rapid response/recovery time (28/5 s), excellent repeatability, and long-term stability. In addition, the Langmuir adsorption isotherm model and the Gibbs free energy were used to analyze the adsorption of water molecules on the surface of the lignin film. Finally, the finite element method (FEM) was used to analyze the fringing field distributions of the QCMs with symmetric and ringed electrode. The sensitivity enhancement mechanism of the lignin-based QCM humidity sensor with ringed electrode configuration was discussed through the equivalent electronic circuit analysis and simulation methods. This work demonstrates that the lignin is a potential candidate material for humidity detection, and it is an excellent method to improve the humidity sensitivity of QCM sensors through optimizing the electrode structure configuration using fringing field effect. [ABSTRACT FROM AUTHOR]

As a promising new paradigm, Vehicular Edge Computing (VEC) can improve the QoS of vehicular applications by computation offloading. However, with more and more computation-intensive vehicular applications, VEC servers face the challenges of limited resources. In this paper, we study how to effectively and economically utilize the idle resources in volunteer vehicles to handle the overloaded tasks in VEC servers. First, we present a model of volunteer assisted vehicular edge computing, in which the cost and utility functions are defined for requesting vehicles and VEC servers, and volunteer vehicles are encouraged to assist the overloaded VEC servers via obtaining rewards from VEC servers. Then, based on Stackelberg game, we analyze the interactions between requesting vehicles and VEC servers, and find the optimal strategies for them. Furthermore, we prove theoretically that the Stackelberg game between requesting vehicles and VEC servers has a unique Stackelberg equilibrium, and propose a fast searching algorithm based on genetic algorithm to find the best pricing strategy for the VEC server. In addition, to maximize the reward of volunteer vehicles, we propose the volunteer task assignment algorithm for optimal mapping between the tasks and volunteer alliances. Finally, the effectiveness of the proposed scheme is demonstrated through a large number of simulations. Compared with other schemes, the proposed scheme can reduce the offloading cost of vehicles and improve the utility of VEC servers. [ABSTRACT FROM AUTHOR]

Quartz crystal microbalance (QCM) has been widely used in various fields. The mass sensitivity of QCM that means the ratio between the resonant frequency shift and the mass change on the surface of the crystal wafer is a significant parameter. The accuracy of the mass sensitivity value can greatly affect the data analysis, which in turn affects the repeatability of the QCM-related experiment. Meanwhile, we noticed that most companies that provide QCMs do not give out specific electrode thickness values but a wide range of 400–10 000Å. In this letter, we quantitatively studied the effect of electrode thickness on mass sensitivity of QCM through theoretical calculation and experiment. The result shows the mass sensitivity of QCM with 10 000-Å thickness is 1.46 times and 2.08 times that of 1000- and 400-Å thickness, respectively. Obviously, the uncertainty in electrode thickness values provided by companies inevitably brings large experimental errors, which lead to inaccuracy and poor repeatability of QCM experiment. Therefore, we suggest that the companies providing QCMs should give the specific value of the electrode thickness, and then the researchers should also consider the influence of the electrode thickness when analyzing the data to improve the accuracy and repeatability. [ABSTRACT FROM AUTHOR]