Map matching for circular road via contextual voting

Due to the limitation of positioning devices, there is a certain error between GPS positioning data and the real location on the map, and the positioning data needs to be processed to have better usability. For example, accurate location is needed for traffic flow control, automatic driving navigation, logistics tracking, etc. There are few studies specifically for circular road sections. In addition, many existing map matching methods based on Hidden Markov model (HMM) also have the problem that GPS points are easily to be matched to tangent or non-adjacent road sections at circular road sections. Therefore, the contextual voting map matching method for circular road sections (STDV-matching) is proposed. The method proposes multiple subsequent point direction analysis methods based on STD-matching to determine entry into the circular section, and adds candidate section frequency voting analysis to reduce matching errors. The effectiveness of the proposed method is verified at the circular section by comparing it with three existing HMM methods through experiments using two real map and trajectory datasets.

Clusters of Spin Valve Sensors in 3D Magnetic Field of a Label

Magnetic field sensors based on the giant magnetoresistance (GMR) effect have a number of practical current and future applications. We report on a modeling of the magnetoresistive response of moving spin-valve (SV) GMR sensors combined in certain cluster networks to an inhomogeneous magnetic field of a label. We predicted a large variety of sensor responses dependent on the number of sensors in the cluster, their types of interconnections, the orientation of the cluster, and the trajectory of sensor motion relative to the label. The model included a specific shape of the label, producing an inhomogeneous magnetic field. The results can be used for the optimal design of positioning devices.

Innovative software solutions for subsea positionings

<p>Improving operational efficiency is a recurring challenge for subsea operations. Throughout the life of a field, from construction up to decommissioning, several subsea vehicles will be deployed to cover various tasks to perform underwater observations. An ROV or AUV assigned to a specific task will require multiple positioning sensors (LBL, USBL, INS…) to complete its mission. Defining the “good enough” subsea positioning strategy, i.e. to ensure a minimum accuracy without compromise on safety, can be a complex exercise. For instance, an overestimation of the LBL transponders required will directly induce vessel time and finally costly operations. On the other hand, a certain level of positioning redundancy may be requested for a vehicle operating close to a subsea asset in production.</p><p>To ease the design and monitoring of a subsea vehicle navigation, iXblue has developed an integrated solution. Not only has the company broadened its product range with the new intelligent Canopus LBL Transponder and the new generation Ramses transceiver, but with Delph Subsea Positioning Software, iXblue now provides a complete integrated solution for subsea positioning that goes a step further by bringing significant efficiency. Divided in 4 modules (LBL Array Planning, Navigation Simulation, Operations, DelphINS) with an intuitive user interface, Delph Subsea Positioning (DSP) is an integrated software suite for the preparation, the operation and the post-processing of iXblue positioning devices (USBL, LBL and INS).</p>

Advancing Biophysics Using DNA Origami

DNA origami enables the bottom-up construction of chemically addressable, nanoscale objects with user-defined shapes and tailored functionalities. As such, not only can DNA origami objects be used to improve existing experimental methods in biophysics, but they also open up completely new avenues of exploration. In this review, we discuss basic biophysical concepts that are relevant for prospective DNA origami users. We summarize biochemical strategies for interfacing DNA origami with biomolecules of interest. We describe various applications of DNA origami, emphasizing the added value or new biophysical insights that can be generated: rulers and positioning devices, force measurement and force application devices, alignment supports for structural analysis for biomolecules in cryogenic electron microscopy and nuclear magnetic resonance, probes for manipulating and interacting with lipid membranes, and programmable nanopores. We conclude with some thoughts on so-far little explored opportunities for using DNA origami in more complex environments such as the cell or even organisms. Expected final online publication date for the Annual Review of Biophysics, Volume 50 is May 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Acceptance and Image Quality of High-Resolution Peripheral Quantitative Computed Tomography of the Metacarpophalangeal Joints in Rheumatoid Arthritis.

Objective: To investigate the acceptance of the high-resolution peripheral quantitative computed tomography (HR-pQCT) in rheumatoid arthritis (RA). The second objective was to investigate the motion artefacts of the metacarpophalangeal (MCP) joints with two different custom-made positioning devices. Methods: Fifty patients with established RA had their MCP joints scanned by HR-pQCT with two different custom-made positioning devices and examined by conventional X-ray. Afterwards, the patients answered a questionnaire of imaging experience. The comparability of the erosion measures was investigated between the two different custom-made positioning devices by Bland-Altman plot, and intrareader repeatability by intraclass correlation coefficient. The motion artefacts were graded for each acquisition, and intrareader repeatability was investigated by Cohen's kappa coefficient.Results: Forty percent of the patients preferred HR-pQCT imaging, only 6% preferred conventional X-ray. Seventy-four percent found it difficult to keep their fingers steady during the scan. Fifty percent of the patients reported the inflatable immobilization device helped to keep their fingers steady while only 6% reported that it impaired their ability to do so. However, this difference was not reflected in the visual grading, as motion artefacts were sparse, and no clinically relevant difference could be observed. The intrareader repeatability and comparability for the erosion measures were excellent.Conclusion: The high acceptance among patients adds to the feasibility of HR-pQCT imaging of MCP joints in patients with RA. The inflatable immobilization device did not reduce motion-induced image degradation, as the overall visual grading for motion artefacts was low for imaging of the MCP joints in both acquisitions.