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Constructing electrode materials with fast ions and electrons transport channels is an effective solution to achieve high-power-density and longcycle potassium-ion batteries (PIBs). Herein, completely opening radial pores in N/O dual-doped carbon nanospheres (RPCNSs) are constructed as anode for high-power PIBs. The RPCNS with hierarchical structure (micro/ meso/macropores and radial channels) and N/O dual-doping permits speedy ions and electrons transportation within the carbon nanospheres anode, achieving a reversible capacity of 346 mAh g −1 at 50 mA g −1 after 360 cycles and long-term cycling life over 2000 cycles without obvious capacity attenuation. The in situ Raman and kinetic analysis (in situ electrochemical impedance spectroscopy and galvanostatic intermittent titration) suggest that the exquisitely designed pore structure and heterodoping enable highly reversible electrochemical reaction and fast de/ intercalation kinetics. Moreover, the full cells packaged with RPCNS anode can be fully charged in 10 s and exhibit the highest charge power density of 24 866 W kg −1 and longest cycling endurance of 5000 cycles in reported PIBs. The unique structural engineering provides a new way for high-power density potassium-ion storage devices.

The LoRaWAN based Low Power Wide Area networks aim to provide long-range connectivity to a large number of devices by exploiting limited radio resources. The Adaptive Data Rate (ADR) mechanism controls the assignment of these resources to individual end-devices by a runtime adaptation of their communication parameters when the quality of links inevitably changes over time. This paper provides a detailed performance analysis of the ADR technique presented in the recently released LoRaWAN Specifications (v1.1). We show that the ADR technique lacks the agility to adapt to the changing link conditions, requiring a number of hours to days to converge to a reliable and energy-efficient communication state. As a vital step towards improving this situation, we then change different control knobs or parameters in the ADR technique to observe their effects on the convergence time.

Potassium-ion hybrid capacitors (PIHCs) show great potential in largescale energy storage due to the advantages of electrochemical capacitors and potassium-ion batteries. However, their development remains at the preliminary stage and is mainly limited by the kinetic imbalance between the two electrodes. Herein, an architecture of NbSe 2 nanosheets embedded in N, Se co-doped carbon nanofibers (NbSe 2 /NSeCNFs) as flexible, free-standing, and binder-free anodes for PIHCs is reported. The NbSe 2 /NSeCNFs with hierarchically porous structure and N, Se co-doping afford highly efficient channels for fast transportation of potassium ions and electrons during repeated cycling process. Furthermore, excellent electrochemical reversibility of the NbSe 2 /NSeCNFs electrode is demonstrated through in situ XRD, in situ Raman, ex situ transmission electron microscopy and element mapping. Thus, PIHCs with the NbSe 2 /NSeCNFs anode and active carbon cathode achieve a high energy of 145 W h kg −1 at a current density of 50 mA g −1 , as well as an ultra-long cycle life of over 10 000 cycles at a high current density of 2 A g −1. These results indicate that the assembled PIHCs display great potential for applications in the field of ultra-long cycling energy storage devices.

The corrosion of Li‐ and Mn‐rich (LMR) electrode materials occurring at the solid–liquid interface will lead to extra electrolyte consumption and transition metal ions dissolution, causing rapid voltage decay, capacity fading, and detrimental structure transformation. Herein, a novel strategy is introduced to suppress this corrosion by designing an Na + ‐doped LMR (Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 ) with abundant stacking faults, using sodium dodecyl sulfate as surfactant to ensure the uniform distribution of Na + in deep grain lattices—not just surface‐gathering or partially coated. The defective structure and deep distribution of Na + are verified by Raman spectrum and high‐resolution transmission electron microscopy of the as‐prepared electrodes before and after 200 cycles. As a result, the modified LMR material shows a high reversible discharge specific capacity of 221.5 mAh g −1 at 0.5C rate (1C = 200 mA g −1 ) after 200 cycles, and the capacity retention is as high as 93.1% which is better than that of pristine‐LMR (64.8%). This design of Na + is uniformly doped and the resultanting induced defective structure provides an effective strategy to enhance electrochemical performance which should be extended to prepare other advanced cathodes for high performance lithium‐ion batteries.

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As a new method of Earth observation, video satellite is capable of monitoring specific events on the Earth's surface continuously by providing high-temporal resolution remote sensing images. The video observations enable a variety of new satellite applications such as object tracking and road traffic monitoring. In this article, we address the problem of fast object tracking in satellite videos, by developing a novel tracking algorithm based on correlation filters embedded with motion estimations. Based on the kernelized correlation filter (KCF), the proposed algorithm provides the following improvements: 1) proposing a novel motion estimation (ME) algorithm by combining the Kalman filter and motion trajectory averaging and mitigating the boundary effects of KCF by using this ME algorithm and 2) solving the problem of tracking failure when a moving object is partially or completely occluded. The experimental results demonstrate that our algorithm can track the moving object in satellite videos with 95% accuracy.

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