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Load aggregators (LA) face the uncertainty of load and price when they participate in load curtailment bidding (LCB) in power market. A day ahead optimization model with the objective of minimizing the agency cost of LA is proposed. In this paper, the power purchase, LCB and the control of adjustable load are described as a mixed integer linear programming model. A bi-level programming model is used to deal with the uncertain load, so as to the historical scenario method to uncertain price combined with scenario reduction. Based on the data of Pennsylvania-New Jersey-Maryland (PJM) power market, the proposed strategy is analysed. The results show that the proposed strategy and scenario reduction method can reduce the aggregators' agency cost by more than 4% and risks by more than 10%, improve the performance rate by up to 17.8%, and provide bidding technical support for the LA under uncertain problems.

Simple Summary: In intelligent agriculture, non-contact, automatic body size measurement is widely used for livestock. However, the common measurement methods based on the whole point cloud are complex and prone to errors because of the positions of the cattle. To measure the body sizes of livestock more accurately, a cattle body measuring system is proposed. The system includes a new algorithm called dynamic unbalanced octree grouping (DUOS), based on PointNet++, and an efficient method of body size measurement based on segmentation results. The network divides the cow into the following seven parts: body length, withers height, hip height, thoracic circumference, abdominal circumference, and cannon circumference. Compared with some of the other models, the system has higher segmentation accuracy and lower measurement errors. The system can be widely applied in the non-contact body measurement of livestock; in addition, it can increase efficiency and reduce costs. It also has broad prospects in the intelligent livestock industry. The common non-contact, automatic body size measurement methods based on the whole livestock point cloud are complex and prone to errors. Therefore, a cattle body measuring system is proposed. The system includes a new algorithm called dynamic unbalanced octree grouping (DUOS), based on PointNet++, and an efficient method of body size measurement based on segmentation results. This system is suitable for livestock body feature sampling. The network divides the cow into seven parts, including the body and legs. Moreover, the key points of body size are located in the different parts. It combines density measurement, point cloud slicing, contour extraction, point cloud repair, etc. A total of 137 items of cattle data are collected. Compared with some of the other models, the DUOS algorithm improves the accuracy of the segmentation task and mean intersection by 0.53% and 1.21%, respectively. Moreover, compared with the manual measurement results, the relative errors of the experimental measurement results are as follows: withers height, 1.18%; hip height, 1.34%; body length, 2.52%; thoracic circumference, 2.12%; abdominal circumference, 2.26%; and cannon circumference, 2.78%. In summary, the model is proven to have a good segmentation effect on cattle bodies and is suitable for cattle body size measurement. [ABSTRACT FROM AUTHOR]

Little scientific knowledge is available for short‐finned pilot whales in the South China Sea (SCS). Here, we integrated historical records, ship‐based observation, and satellite‐tagging data to investigate ecological and behavioral characteristics of pilot whales in the SCS. Historical records since the 1990s showed the widespread spatial occurrence of pilot whales along the coastal SCS, suggesting that the species may inhabit this region. During our dedicated ship‐based surveys (2019–2022) in the SCS, 19 groups of pilot whales were encountered in Xisha‐Zhongsha waters, which supported the hypothesis inferred from historical data. We believe that Xisha‐Zhongsha waters are important habitats for pilot whales, demonstrated by the large group size (M = 44.7 ± 42.4 SD individuals), the high proportion of recorded maternal groups (17/19), mixed‐species associations, and deep‐water habitat characteristics. During field surveys, we conducted satellite‐tagging experiments on two adult pilot whales, with tracking periods of 35 and 13 days, respectively. Satellite‐tracking data provided evidence of possible residency of the tagged whales, as both displayed overlapping ranges and nondirectional movement. This research provides preliminary baseline data on occurrence, distribution, movement, habitat use, and likely residency of pilot whales in the SCS, which can facilitate future research and conservation effort. [ABSTRACT FROM AUTHOR]

Tooth rake marks are usually used as an indicator of received aggression in odontocetes whose social interactions are difficult to observe directly. Photographic data from five locations of the northern South China Sea were used to analyze seasonal, demographic, and geographic effects on the density of tooth rake marks and dorsal fin notches in Indo‐Pacific humpback dolphins (Sousa chinensis, IPHDs). The analysis revealed that fresh tooth rake marks were most frequent during the dry season. Males exhibited significantly higher rake mark density than females and rake density declined significantly with age. The density of notches was also significantly higher for males than for females, and lower for young dolphins than for mid‐aged and adult ones. Geographically, tooth rake mark and notch density were the highest in Sanniang Bay and Southwestern Hainan. These results provide indirect evidence of variation in social interactions across seasons, across the lifespan of an individual, between sexes, and among different locations. This variation may result from changes in biological parameters, differences in social lives, and habitat characteristics. A model to determine the sex of dolphins was tested, and after further validation, such sex assignment could contribute to understanding IPHDs' social structure. [ABSTRACT FROM AUTHOR]