[1] After decades of research on continental tectonics, there is still no consensus on the mode of deformation of continents or on the forces that drive their deformation. In Asia the debate opposes edge-driven block models, requiring a strong lithosphere with strain localized on faults, to buoyancy-driven continuous models, requiring a viscous lithosphere with pervasive strain. Discriminating between these models requires continent-wide estimates of lithospheric strain rates. Previous efforts have relied on the resampling of heterogeneous geodetic and Quaternary faulting data sets using interpolation techniques. We present a new velocity field based on the rigorous combination of geodetic solutions with relatively homogeneous station spacing, avoiding techniquedependent biases inherent to interpolation methods. We find (1) unresolvable strain rates (<3 Â 10 9 /yr) over a large part of Asia, with current motions well-described by block or microplate rotations, and (2) internal strain, possibly continuous, limited to high-elevation areas.

No abstract

[1] The relevance of plate tectonics concepts to the description of deformation of large continental areas like Asia is subject to much debate. For some, the deformation of continents is better described by rigid motion of lithospheric blocks with strain concentrated along narrow fault zones. For others, it is better described by viscous flow of a continuously deforming solid in which faults play a minor role. Discriminating these end-member hypotheses requires spatially dense measurements of surface strain rates covering the whole deforming area. Here we revisit the issue of the forces and rheological structure that control present-day deformation in Asia. We use the ''thin sheet'' theory, with deformation driven by the balance of boundary and buoyancy stresses acting on a faulted lithosphere with laterally varying strength. Models are validated against a recent, homogeneous, GPS velocity field that covers most of Asia. In the models, deformation in compressional areas (Himalayas, Tien Shan, Altay) is well reproduced with strong coupling at the India/Eurasia plate contact, which allows for boundary forces to transfer into Asia. Southeastward motions observed in north and south China, however, require tensional, oceanward directed stresses, possibly generated by gravitational potential energy gradients across the Indonesian and Pacific subductions. Model and observed strain rates show that a large part of Asia undergoes no resolvable strain, with a kinematics apparently consistent with block-or plate-like motions. Internal strain, possibly continuous, is limited to high-elevation, mechanically weaker areas. Lateral variations of lithospheric strength appear to control the style of deformation in Asia, with a dynamics consistent with the thin sheet physical framework.

No abstract

In this paper we outline a front-tracking method for computing the moving contact line. In particular, we are interested in the motion of two-dimensional drops and bubbles on a partially wetting surface exposed to shear flows. Peskin's Immersed Boundary Method is used to model the liquid-gas interface, similar to the approach used by Unverdi and Traggvason. The movement near the moving contact line is modelled by a slip condition, the value of the dynamic contact angle is determined by a linear model, and the local forces are introduced at the moving contact lines based on a relationship of moving contact angle and contact line speed. Numerical examples show that the method can be applied to the motion of drops and bubbles on a solid surface over a wide range of parameter values.

We present a novel measurement method based on the gravimetric principles adapted from the ASTM E542 and ISO 4787 standards for quantitative volume determination in the sub-microliter range. Such a method is particularly important for the calibration of non-contact micro dispensers as well as other microfluidic devices. The novel method is based on the linear regression analysis of continuously monitored gravimetric results and therefore is referred to as ‘gravimetric regression method (GRM)’. In this context, the regression analysis is necessary to compensate the mass loss due to evaporation that is significant for very small dispensing volumes. A full assessment of the measurement uncertainty of GRM is presented and results in a standard measurement uncertainty around 6 nl for dosage volumes in the range from 40 nl to 1 µl. The GRM has been experimentally benchmarked with a dual-dye ratiometric photometric method (Artel Inc., Westbrook, ME, USA), which can provide traceability of measurement to the International System of Units (SI) through reference standards maintained by NIST. Good precision (max. CV = 2.8%) and consistency (bias around 7 nl in the volume range from 40 to 400 nl) have been observed comparing the two methods. Based on the ASTM and ISO standards on the one hand and the benchmark with the photometric method on the other hand, two different approaches for establishing traceability for the GRM are discussed.

Can you find me? By simulating how humans to discover the so-called 'perfectly'-camouflaged object, we present a novel boundary-guided separated attention network (call BSA-Net). Beyond the existing camouflaged object detection (COD) wisdom, BSA-Net utilizes two-stream separated attention modules to highlight the separator (or say the camouflaged object's boundary) between an image's background and foreground: the reverse attention stream helps erase the camouflaged object's interior to focus on the background, while the normal attention stream recovers the interior and thus pay more attention to the foreground; and both streams are followed by a boundary guider module and combined to strengthen the understanding of boundary. The core design of such separated attention is motivated by the COD procedure of humans: find the subtle difference between the foreground and background to delineate the boundary of a camouflaged object, then the boundary can help further enhance the COD accuracy. We validate on three benchmark datasets that the proposed BSA-Net is very beneficial to detect camouflaged objects with the blurred boundaries and similar colors/patterns with their backgrounds. Extensive results exhibit very clear COD improvements on our BSA-Net over sixteen SOTAs.

Low-light image enhancement (LLE) remains challenging due to the unfavorable prevailing low-contrast and weak-visibility problems of single RGB images. In this paper, we respond to the intriguing learning-related question -- if leveraging both accessible unpaired over/underexposed images and high-level semantic guidance, can improve the performance of cutting-edge LLE models? Here, we propose an effective semantically contrastive learning paradigm for LLE (namely SCL-LLE). Beyond the existing LLE wisdom, it casts the image enhancement task as multi-task joint learning, where LLE is converted into three constraints of contrastive learning, semantic brightness consistency, and feature preservation for simultaneously ensuring the exposure, texture, and color consistency. SCL-LLE allows the LLE model to learn from unpaired positives (normal-light)/negatives (over/underexposed), and enables it to interact with the scene semantics to regularize the image enhancement network, yet the interaction of high-level semantic knowledge and the low-level signal prior is seldom investigated in previous methods. Training on readily available open data, extensive experiments demonstrate that our method surpasses the state-of-the-arts LLE models over six independent cross-scenes datasets. Moreover, SCL-LLE's potential to benefit the downstream semantic segmentation under extremely dark conditions is discussed. Source Code: https://github.com/LingLIx/SCL-LLE.