Search Results (3)

This study empirically analyzes how the Hallyu (Korean Wave) phenomenon affects Korea’s consumer goods exports to China using Chinese provincial-level panel data covering the period from 2011 to 2020. This paper adopts Baidu Index big data with the keywords “Korean drama”, “Korean movie”, “Korean music”, and “Korean entertainment” as proxy variables for Hallyu. The paper investigates the impact of Hallyu on Korean consumer goods exports by subdividing consumer goods into seven processing steps. In addition to the effect of the composite Hallyu index, the effect of each Hallyu content is also examined. Moreover, this study also investigates the impact of the political issue of the deployment of the THAAD American anti-ballistic missile defense system by dividing the period from 2011 to 2020 into before and after 2016. An export equation that includes income level, the Hallyu index, as well as other variables recognized as factors affecting Korea’s exports in existing studies, is used. Several interesting conclusions have been reached. First, Hallyu in China has a significant impact on Korea’s exports of non-durable consumer goods and processed household food and beverages to China. Second, the political issue of the deployment of THAAD has a negative impact on Korea’s exports of consumer goods to China. Third, among the four types of Hallyu content, dramas, as the most popular content in China, have the greatest influence on Korea’s exports of consumer goods to China. Full article

The recognition of warheads in the target cloud of the ballistic midcourse phase remains a challenging issue for missile defense systems. Considering factors such as the differing dimensions of the features between sensors and the different recognition credibility of each sensor, this paper proposes a weighted decision-level fusion architecture to take advantage of data from multiple radar sensors, and an online feature reliability evaluation method is also used to comprehensively generate sensor weight coefficients. The weighted decision-level fusion method can overcome the deficiency of a single sensor and enhance the recognition rate for warheads in the midcourse phase by considering the changes in the reliability of the sensor’s performance caused by the influence of the environment, location, and other factors during observation. Based on the simulation dataset, the experiment was carried out with multiple sensors and multiple bandwidths, and the results showed that the proposed model could work well with various classifiers involving traditional learning algorithms and ensemble learning algorithms. Full article

It is crucial for a ballistic missile defense system to discriminate the true warhead from decoys. Although a decoy has a similar shape to the warhead, it is believed that the true warhead can be separated by its micro-Doppler features introduced by the precession and nutation. As is well known, the accuracy of the phase-derived range method, to extract micro-Doppler curves, can reach sub-wavelength. However, it suffers from an inefficiency of energy integration and high computational costs. In this paper, a novel phase-derived range method, using high-order multi-frame track-before-detect is proposed for micro-Doppler curve extraction under a low signal-to-noise ratio (SNR). First, the sinusoidal micro-Doppler range sequence is treated as the state, and the dynamic model is described as a Markov chain to obtain the envelopes and then the ambiguous phases. Instead of processing the whole frames, the proposed method only processes the latest frame at an arbitrary given time, which reduces the computational costs. Then, the correlation of all pairs of adjacent pulses is calculated along the slow time dimension to find the number of cells that the point scatterer crosses, which can be further used in phase unwrapping. Finally, the phase-derived range method is employed to get the micro-Doppler curves. Simulation results show that the proposed method is capable of extracting the micro-Doppler curves with sub-wavelength accuracy, even if SNR = −15 dB, with a lower computational cost. Full article