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In this paper, we propose a real time system for tracking targets across blind regions of multiple cameras with non-overlapping fields of views (FOVs) using camera topology, and targets' motion and shape information. Kalman filters are used to robustly track each target's shape and motion in each camera view and the common ground plane view composed of all camera views. The target's track in the blind region between cameras is obtained using Kalman filter predictions. For multi-camera correspondence matching we compute the Gaussian distributions of the tracking parameters across cameras for the target motion and position in the ground plane view. Matching of targets across camera views uses a graph based track initialization scheme, which accumulates information from occurrences of target in several consecutive frames of the video. Probabilistic matching is carried out by using the track parameters for new tracks obtained from the graph in a camera view with the parameters of the terminated tracks learnt by Kalman filters in the other camera views and ground plane view. We obtain 85% accuracy for corresponding matching while tracking vehicles observed from two cameras monitoring a highway.

The first data set of seasonal marine environment and euphotic zone integrated primary production (IP) variations in the Taiwan Strait was reported. The measured annual IP was 123 ± 86 gC m −2 year −1 (338 ± 235 mgC m −2 day −1), and its seasonal variations can be described with a left-skewed normal distribution curve. The average seasonal IP values from the highest to the lowest were summer (664 ± 270 mgC m −2 day −1), autumn (350 ± 118 mgC m −2 day −1), spring (202 ± 110 mgC m −2 day −1), and winter (137 ± 68 mgC m −2 day −1). The lowest IP was during the nutrient-rich winter because it had a short insolation duration, low incident photosynthetic active radiation (PAR) and low light transmission (shallow euphotic zone depth) due to strong vertical mixing. In contrast to the winter, the highest IP was during the nutrient-depleted summer, which had a long insolation duration, high incident PAR and high light transmission (deeper euphotic zone depth). In addition, the heterotrophic nutrients from upwelling in the south might also support the highest IP in summer. As three primary water masses exist in the Taiwan Strait and three of them have different characteristics, different mixing ratios of water masses may cause different chemical and hydrographic conditions, which leads to different levels of Chl a concentrations and primary production. It is worth to mention that offshore wind farm (OWF) construction in the Changyun Rise (CYR) of the Taiwan Strait is ongoing. As primary production is the foundation for a marine ecosystem and supports the food web and fish stock, the results of this research can not only be used as the baseline for evaluating the OWF impact on the marine ecosystem but also be used for assessing their influence on fishery resources.

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HF surface wave radar (HFSWR) has been recognized and accepted as an important tool for ocean remote sensing for more than four decades. In this article, a comprehensive tutorial of such an ocean sensor is presented. It begins with the concept of HFSWR. Next, the history of HFSWR is briefly reviewed. Then, the classification of HFSWR in terms of waveform, array signal processing technique, the number of operating frequencies, and configuration geometry is described in detail. Subsequently, the state‐of‐the‐art applications of this type of ocean radar for sea surface current, and wave parameter measurements, wind mapping, and hard targets detection and tracking are presented. The working principles and data processing associated with each application are also explained. The remaining challenges and future trends are also discussed.

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