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Moving target shadows continuously appear in the sequential images produced by video synthetic aperture radar (SAR), which conducts research on shadow-based detection and tracking of moving targets. This article addresses a typical shadow-based detection and tracking problem of dim high-maneuvering targets in the complex background. Building upon the dynamic programming-based track-before-detect (DP-TBD) algorithm, this article proposes a joint-processing-strategy-based DP-TBD (JP-DP-TBD) algorithm to detect and track multiple high-maneuvering targets in video SAR. Benefiting from both of the location and radial velocity information of the targets in the video SAR image and range-Doppler (RD) spectrum, the JP-DP-TBD algorithm can screen the state candidate region and retain more states that conform to the motion law of the target. Meanwhile, we adopt a dual-frame close-range matching mechanism to complete the automatic initialization of the candidate target state, whose validity has been verified on the real video SAR data. Experimental results on simulated data demonstrate that the proposed algorithm has better detection ability and fewer false alarms in comparison with other TBD algorithms.

Research on trust in economic transactions have formed a dichotomous conceptualization of trust as motivated by either economic rationality or emotional intimacy, neglecting other possibilities of trust. Drawing on Simmel’s theorization of the Stranger and Zelizer’s relational perspective, I argue that “stranger trust” is a type of trust that rests on the interactional presentation of objectivity and emotional neutrality. Using interview data with mental health service consumers in China, I address the question: how do participants of therapeutic relationships form trust under the unfavorable institutional environments for mental health services in China? My findings show that participants in therapeutic relationships create trust by framing the service provider as “Strangers”, which is established through three interactional processes 1) identifying affinities and differences, 2) protecting social distance, and 3) depersonalizing emotions. From the clients’ perspective, these interactional processes mitigate the risk posed by a lack of institutional regulation for mental health service provision. This study calls attention to how relational practices create and maintain trust in settings with weak institutional supports for trust.