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Aimed at the staring imaging requirements of the low earth orbit (LEO) satellite array camera for aerial dynamic targets, a method for target position estimation and staring attitude planning based on image miss-distance of the satellite platform is proposed. Based on the prior knowledge of the flying altitude of the aerial dynamic target, taking the latitude and longitude change rate of the target geography as the state quantity and the central pixel value of the target as the observation, an extended Kalman filter (EKF) is designed to realize the accurate smooth estimation and prediction of the geographical latitude and longitude of the target. On this basis, the attitude and angular velocity of the satellite are planned, the influence of target pixel noise and delay on attitude stability is avoided, and the position estimation of a single satellite to target is realized. The effectiveness of the proposed method is illustrated by a numerical simulation.

In today's era of increasing energy constraints, harnessing the power of electromagnetic waves and converting them into directly usable energy has great potential in the field of renewable energy. This paper presents a highly efficient electromagnetic energy harvester with wide operation angles based on metasurface. The metasurface unit comprises four rotated copper rings plated on a Rogers RT5880 substrate. This unique design incorporates a 3.6 kΩ resistor within each of the four-cornered rotating metal rings, effectively emulating the input impedance circuit of a rectifier. Simulation results reveal that the metasurface achieves a remarkable electromagnetic wave harvesting efficiency of up to 92.3% at a frequency of 5.85 GHz. Additionally, it exhibits polarization insensitivity, enhancing its versatility and suitability for wide incident angles, which augments its practicality in various environments. The proposed metasurface energy harvester represents a significant advancement in electromagnetic energy collection technology, offering an efficient and reliable energy harvesting solution that contributes to addressing energy shortages and is applicable across multiple scenarios. [ABSTRACT FROM AUTHOR]

Objectification, treating others merely as things or tools while denying their personhood, results in severe consequences. While prior research predominantly focused on the triggers of objectification, we aimed to investigate a possible intervention. We hypothesized that gratitude could reduce objectification toward general others (i.e., people who are not the benefactors). Across three studies (N = 1007), our hypothesis was supported. Study 1 showed that dispositional gratitude negatively predicted trait objectification. Studies 2 and 3 further found a causal relationship. Specifically, after heightening participants' state of gratitude, participants showed a lower level of objectification towards others (Study 2). Using a scenario study that described a working context, we further showed the alleviating effect of gratitude on objectification toward a group of factory workers, targets often suffering from objectification (Study 3). Our reported effect is prevalent, such that it is observed across samples from two countries (i.e., the United States and China). [ABSTRACT FROM AUTHOR]