The integrated energy system effectively improves the comprehensive utilization of energy through cascade utilization and coordinated scheduling of various types of energy. Based on the independent integrated energy system, the thermal network interaction between different load characteristic regions is introduced, requiring a minimum thermal grid construction cost, CCHP investment operation cost and carbon emission tax as the comprehensive optimization targets, and making overall optimization to the configuration and operation of the multi-region integrated energy systems. This paper focuses on the planning of equipment capacity of multi-region integrated energy system based on a CCHP system and heat network. Combined with the above comprehensive target and heat network model, a mixed integer linear programming model for a multi-region CCHP system capacity collaborative optimization configuration is established. The integrated energy system, just a numerical model solved with the LINGO software, is presented. Taking a typical urban area in Shanghai as an example, the simulation results show that the integrated energy system with multi-zone heat-suply network interaction compared to the single area CCHP model improved the clean energy utilization of the system, rationally allocates equipment capacity, promotes the local consumption of distributed energy, and provides better overall system benefits.

A high-gain and tri-band terahertz microstrip antenna with a photonic band gap (PBG) substrate is presented in this paper for terahertz communications. Polyimide dielectric columns are inserted into the silicon substrate to form the PBG substrate to improve the gain of the antenna. The PBG substrate and polyimide substrate constituted a multilayer substrate structure and enabled the multi-band operation of the antenna. The PBG substrate antenna achieves gains of 6.28 dB, 4.84 dB, and 7.66 dB at resonant frequencies of 0.360 THz, 0.580 THz, and 0.692 THz, respectively, outperforming the homogeneous substrate THz microstrip antenna (H antenna) by 1.18 dB, 1.74 dB, and 1.82 dB, respectively. The radiation efficiencies at three operating bands are over 93%, 92%, and 88%, respectively, which are slightly higher than that of the H antenna and greater than that of the standard multi-band antenna.

In this paper, a hybrid system topology with one-way wireless charging function and the function of the bi-directional data communication is proposed for the problem of electric energy replenishment and data transmission faced by robot fish in the implementation of autonomous submarine cable inspection. Three working modes of the system and the time-sharing multiplexing method are studied. In the power transmission mode, high-efficiency wireless charging is realized by utilizing the transmission characteristics of a series–series (SS)-type resonant network which involves series resonant networks in both the primary side and the secondary side. In the alignment detection and handshake communication mode, the charging platform distance recognition and the handshake signal transmission are implemented through a series–parallel (SP)-type resonant network based on the ASK (amplitude shift keying) modulation method. In the high-speed data transmission mode, the reverse (secondary to primary) high-speed transmission of the inspection data is achieved through a SP-type resonant network based on the OFDM (orthogonal frequency division multiplexing) modulation method. The three modes share the same coupled coils via a reconfigurable resonant network. The working principle of the system is expounded, the system characteristics under each working mode are analyzed, and the time-division multiplexing control strategy is given. The rationality and effectiveness of the scheme are verified by experiments.

Aiming at the output control issues of a lithium ion battery wireless charging system, a primary side control method based on load characteristic identification is proposed. The primary side impedance is calculated by detecting the effective value of the primary side voltage and current, and the mapping relationship between the equivalent load and the primary side impedance is established based on the AC impedance model. Using this mapping relation, the output of the secondary side can be regulated indirectly by controlling the input voltage of the inverter. Compared with the traditional control methods, the proposed control method not only eliminates the communication requirement between the primary side and secondary side, but also simplifies the hardware circuit design, reduces the complexity of the control circuit and also reduces the volume and cost of the system. In the paper, the impedance characteristics of the lithium ion battery at constant current and constant voltage stage are analyzed. The principle of the primary side control method is expounded and the realization method is given. The feasibility of the proposed control method is verified by simulation and experiment.

With the working frequency of wireless communication systems moving to a higher terahertz (THz) band, the design of high-performance THz wave modulators has become a pivotal issue to be tackled urgently in THz communication. In this paper, we design a high-performance dual-channel photonic crystal modulator to enable ON–OFF regulation of the THz wave based on the defect mode disappearance of combined microcavities. The modulator introduces Y-type line defects into silicon rod photonic crystals as a dual-channel waveguide and the point defects and ring resonator form a combined microcavity. Due to the refractive index of the ring resonator filler, gallium arsenide, it is tunable with pump light excitation, and the defect mode frequency of the combined microcavity can be dynamically changed. Under pump excitation with a wavelength of 810 nm and an intensity of 0.4 μJ/cm², 1.34 THz and 1.83 THz dual-channel waves can be OFF due to the defect mode disappearance of the combined microcavity. This is simulated by the time-domain steady-state response and steady-state THz wave field intensity distribution of the modulator by the finite-difference time-domain method. The results indicate that the dual-channel modulator has large modulation depths of 100% and 99.7%, high modulation rates of 4.05 GHz and 4.17 GHz, and low insertion losses of 0.31 dB and 0.18 dB, which lays foundation for the development of high-speed and low-loss THz communication technology.

With the widespread adoption of renewable energy, distribution grids face increasing challenges in efficiency, safety, and economic performance due to stochastic generation and fluctuating load demand. Traditional operational models often exhibit limited adaptability, weak coordination, and insufficient holistic optimization, particularly in early-/mid-stage distribution planning where feeder-level network information may be incomplete. Accordingly, this study adopts a planning-oriented formulation and proposes a distributed energy storage system (DESS) planning strategy to enhance distribution network resilience under high uncertainty. First, representative wind and photovoltaic (PV) scenarios are generated using an improved Gaussian Mixture Model (GMM) to characterize source-side uncertainty. Based on a grid-based network partition, a priority index model is developed to quantify regional storage demand using quality- and efficiency-oriented indicators, enabling the screening and ranking of candidate DESS locations. A mixed-integer linear multi-objective optimization model is then formulated to coordinate lifecycle economics, operational benefits, and technical constraints, and a sequential connection strategy is employed to align storage deployment with load-balancing requirements. Furthermore, a node–block–grid multi-dimensional evaluation framework is introduced to assess resilience enhancement from node-, block-, and grid-level perspectives. A case study on a Zhejiang Province distribution grid—selected for its diversified load characteristics and the availability of detailed historical wind/PV and load-category data—validates the proposed method. The planning and optimization process is implemented in Python and solved using the Gurobi optimizer. Results demonstrate that, with only a 4% increase in investment cost, the proposed strategy improves critical-node stability by 27%, enhances block-level matching by 88%, increases quality-demand satisfaction by 68%, and improves grid-wide coordination uniformity by 324%. The proposed framework provides a practical and systematic approach to strengthening resilient operation in distribution networks.