We propose a novel methodology for re-identification, based on Pictorial Structures (PS). Whenever face or other biometric information is missing, humans recognize an individual by selectively focusing on the body parts, looking for part-to-part correspondences. We want to take inspiration from this strategy in a re-identification context, using PS to achieve this objective. For single image re-identification, we adopt PS to localize the parts, extract and match their descriptors. When multiple images of a single individual are available, we propose a new algorithm to customize the fit of PS on that specific person, leading to what we call a Custom Pictorial Structure (CPS). CPS learns the appearance of an individual, improving the localization of its parts, thus obtaining more reliable visual characteristics for re-identification. It is based on the statistical learning of pixel attributes collected through spatio-temporal reasoning. The use of PS and CPS leads to state-of-the-art results on all the available public benchmarks, and opens a fresh new direction for research on re-identification.

A B S T R A C TThis paper presents a comprehensive study on the complex drill-exit temperature characteristics in the drilling of unidirectional (UD) and multidirectional (MD) CFRPs using a state-of-art microscopy infrared imaging system. For the first time, temperature variation and distribution at drill exit have been revealed in full detail, associated with the CFRP material properties and drilling conditions. Results suggest that the actual drill/CFRP interactions have critical but similar effects on the drill-exit temperatures for UD and MD CFRPs. Specifically, three distinct cutting regions with varying temperature characteristics are evident when the main cutting edge is acting on the drill exit material. In all cases, the temperature distribution features elliptical shape, of which the eccentricity depends on the lay-up sequence and the drilling depth. In addition, the real-time temperature profiles and 2D/3D maximum temperature distribution maps are created with high visualization. With the aid of those findings, the relationships between drilling temperature maxima, their locations and drilling depths have been discovered and temperature effects on drill-exit damages have been elucidated for the first time. MD CFRP is proven more difficult to achieve high drilling qualities at certain fiber cutting angles than UD CFRP due to the associated temperature effects. Such important knowledge enables the identification of the heat affected zones and subsequently informs strategies for reducing the negative temperature effects.

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As a promising candidate for rapid and ultrasensitive sensing of biomolecules, terahertz (THz) time‐domain spectroscopy is widely used in label‐free, noncontact, noninvasive, and nondestructive detection. In this article, planar Jerusalem cross metamaterial absorber for different virus detection based on spoof surface plasmon polaritons (SSPPs) in THz band is investigated. Strongly confined SSPPs modes are extracted from the absorption spectra of biosensing metamaterial absorber associated with local field enhancement. Meanwhile, equivalent complex refractive index (N) of different virus subtypes and protein concentrations is numerically investigated for virus detection. Besides, simulated detections for different virus subtypes (different N) are probed with the proposed biosensing metamaterial absorber. Especially for the simulated detections of three representative Avian Influenza viruses (H5N2, H1N1, H9N2), the proposed THz biosensing metamaterial absorber chip performed ultrasensitive sensitivity and high resolution by extracting the shifted resonance frequencies (ΔF) and the changed values at maximum absorptions (ΔA). All these findings show great significance on a rapid real‐time procedure for diseases diagnosis especially for the contagious and time‐sensitive target virus. The proposed ultrasensitive and selective THz metamaterial absorber opens up a new way for planar biosensing chip to be developed into practical applications in THz regime.

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