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Multimodal remote sensing image matching is still a challenging task, and its matching performance will highly influence the subsequent applications, such as image fusion, image mosaic and change detection. To tackle this problem, we propose a radiometric and rotational invariant descriptor (RRID) using the monogenic signal for multimodal image matching. First of all, a multiscale feature asymmetry measurement is proposed to obtain more reliable detected points, in which the multiscale feature asymmetry can be computed from the intermediate results from the monogenic signal; then a multiscale local phase orientation computation algorithm is designed for the main orientation assignment of each keypoint, in which the local phase orientation can also be provided by the monogenic signal construction; finally, a circular local window around each keypoint is extracted, a histogram of local phase orientations weighted by phase congruency is calculated for the log-polar feature description. RRID is compared with other state-of-the-art multimodal image matching methods on three publicly available datasets. Experimental results have demonstrated that our proposed method outperforms the compared methods in terms of precision, recall, and F1-measure criteria and also has achieved the lowest RMSEs. [ABSTRACT FROM AUTHOR]

The use of waste apple-wood as a source of sawdust to cultivate the mushrooms Pleurotus ostreatus and Lentinula edodes is a common practice, but it is imperative to ensure that the wood does not contain unsafe amounts of heavy-metals or pesticide residues. In this study, we sampled and investigated the pollution of heavy metals and pesticide residues in apple-wood from Yantai, Shandong, China and cultivated P. ostreatus and L. edodes using apple-wood as substrate. Heavy metals, pesticide residues, mineral elements, and biological efficiency were measured. Heavy metals were more commonly detected in the 73 apple-wood samples, but serious pollution was only an isolated phenomenon. No Pb was detected in P. ostreatus and L. edodes. The contents of Hg, As, Cd, and Cr were at safe levels. The contents of Ni were equivalent to those of wild mushrooms. Most notably, chlorpyrifos was detected in all the apple-wood tested. However, chlorpyrifos was only detected in L. edodes cultivated with apple sawdust. No other pesticide residues were detected in the other mushroom samples. The biological efficiency of P. ostreatus cultivated by apple sawdust was 89%, which was 80% of the control. The biological efficiency of L. edodes cultivated with apple sawdust was 81%, which did not differ significantly from the control. Apple-wood can replace wild oak as the material for L. edodes cultivation, but producers should ensure that the raw materials are safe. The main materials chosen to cultivate P. ostreatus should balance the two factors of raw material price and biological efficiency. [ABSTRACT FROM AUTHOR]

Accurate image registration is a vital step in many computer vision processes. However, traditional SIFT based methods are not able to obtain satisfactory results in some cases. In this paper, we turn the matching problem into a Markov Random Field (MRF) optimization problem and propose a fast and accurate image registration method based on message passing to screen out mismatches caused by the conventional SIFT-based algorithm. The proposed method comprises three steps. First, a SIFT detector is used to detect key points and then these points are described by Daisy instead of the SIFT detector (to improve efficiency); second, a new geometric constraint with distance and direction terms is designed and incorporated into sequential tree-reweighted message passing (TRW-S) – this obtains the coarse matching result; finally, the RANSAC algorithm is adopted to filter out the mismatches and obtain an accurate transformation. The experimental results demonstrate that the proposed method significantly improves the efficiency and the accuracy of the registration process and secures a desirable result. [ABSTRACT FROM AUTHOR]

To address the matching challenge between the High Resolution Imaging Science Experiment (HiRISE) Digital Elevation Model (DEM) and the Mars Orbiter Laser Altimeter (MOLA) DEM, we propose a terrain matching framework based on the combination of point cloud coarse alignment and fine alignment methods. Firstly, we achieved global coarse localization of the HiRISE DEM through nearest neighbor matching of key Intrinsic Shape Signatures (ISS) points in the Fast Point Feature Histograms (FPFH) feature space. We introduced a graph matching strategy to mitigate gross errors in feature matching, employing a numerical method of non-cooperative game theory to solve the extremal optimization problem under Karush–Kuhn–Tucker (KKT) conditions. Secondly, to handle the substantial resolution disparities between the MOLA DEM and HiRISE DEM, we devised a smoothing weighting method tailored to enhance the Voxelized Generalized Iterative Closest Point (VGICP) approach for fine terrain registration. This involves leveraging the Euclidean distance between distributions to effectively weight loss and covariance, thereby reducing the results' sensitivity to voxel radius selection. Our experiments show that the proposed algorithm improves the accuracy of terrain registration on the proposed Curiosity landing area's, Mawrth Vallis, data by nearly 20%, with faster convergence and better algorithm robustness. [ABSTRACT FROM AUTHOR]

The traditional method for extracting the heights of urban buildings involves utilizing dense matching algorithms on stereo images to generate a digital surface model (DSM). However, for urban buildings, the disparity discontinuity issue that troubles the dense matching algorithm makes the elevations of high-rise buildings and the surrounding areas inaccurate. The occlusion caused by trees in greenbelts makes it difficult to accurately extract the ground elevation around the building. To tackle these problems, a method for building height extraction from Gaofen-7 (GF-7) stereo images enhanced by contour matching is presented. Firstly, a contour matching algorithm was proposed to extract accurate building roof elevation from GF-7 images. Secondly, a ground filtering algorithm was employed on the DSM to generate a digital elevation model (DEM), and ground elevation can be extracted from this DEM. The difference between the rooftop elevation and the ground elevation represents the building height. The presented method was verified in Yingde, Guangzhou, Guangdong Province, and Xi'an, Shaanxi Province. The experimental results demonstrate that our proposed method outperforms existing methods in building height extraction concerning accuracy. [ABSTRACT FROM AUTHOR]

Images captured by different sensors with different spectral bands cause non-linear intensity changes between image pairs. Classic feature descriptors cannot handle this problem and are prone to yielding unsatisfactory results. Inspired by the illumination and contrast invariant properties of phase congruency, here, we propose a new descriptor to tackle this problem. The proposed descriptor generation mainly involves three steps. (1) Images are convolved with a bank of log-Gabor filters with different scales and orientations. (2) A window of fixed size is selected and divided into several blocks for each keypoint, and an oriented magnitude histogram and the orientation of the minimum moment of a phase congruency-based histogram are calculated in each block. (3) These two histograms are normalized respectively and concatenated to form the proposed descriptor. Performance evaluation experiments on three datasets were carried out to validate the superiority of the proposed method. Experimental results indicated that the proposed descriptor outperformed most of the classic and state-of-art descriptors in terms of precision and recall within an acceptable computational time. [ABSTRACT FROM AUTHOR]

Background: Internal fixation for severe open articular bone defects is sometimes ineffective or dangerous. In the emergency stage, radical debridement and infection prevention are demanded to provide a good tissue base and the space‐occupying effect to provide enough necessary space to avoid soft‐tissue contraction for the reconstruction. In addition, the 3D printing technology makes individual limb reconstruction a reality. Case Presentation: Here, we present a 31‐year‐old patient with an open fracture and severe bone defect of his left elbow caused by traffic accident, classified as Gustilo–Anderson IIIB. We adopted aggressive debridement and insertion of polymethyl methacrylate (PMMA) to prevent the infection and temporarily construct the bone defect in the emergency stage. Secondly, the total elbow arthroplasty was performed using a unique three‐dimensional (3D) printed prosthesis to reconstruct the elbow joint. During the follow‐up, the elbow movement function was satisfactory. Conclusions: The modified Masquelet technique assisting 3D printing of personalized elbow joint makes the satisfactory functional reconstruction for open high‐energy injuries come true. It could be promoted for the similar surgery of other open joints fractures with severe bone defects. [ABSTRACT FROM AUTHOR]

The Achilles tendon and the bones around the foot and ankle are often exposed after trauma and infection because of the thinness of the soft tissue. Many surgeons consider the distally-based neurocutaneous flap as the first choice for reconstructing soft tissue defects around the ankle, as it provides robust axial perfusion for flaps and is easier to transpose than random pattern local flaps or free flaps. We report here a series of 23 cases of reconstruction of the foot and ankle using a distally-based sural neurocutaneous flap. This flap, which measured from 5 ×× 4 cm2 to 15 ×× 10 cm2, was transferred to cover defects in the soft tissues of the foot and ankle. The short saphenous veins were ligated in 12 cases and retained in the remaining 11 cases. All flaps survived, but two cases with retained short saphenous veins developed venous congestion, including one that progressed to distal necrosis. In conclusion, the distally-based sural neurocutaneous vascular flap provides a valuable tool for the repair of defects in tissues around the ankle. [ABSTRACT FROM AUTHOR]