Horizon-based optical navigation (OPNAV) is an attractive solution for deep space exploration missions, with strong autonomy and high accuracy. In some scenarios, especially those large variations in spacecraft distance from celestial bodies, the visible horizon arc could be very short. this case, traditional Christian–Robinson algorithm least-squares (LS) estimation inappropriate would introdu...

Arc consistency and generalized arc consistency are two of the most important local consistency techniques for binary and non-binary classic constraint satisfaction problems (CSPs). Based on the Semiring CSP and Valued CSP frameworks, arc consistency has also been extended to handle soft constraint satisfaction problems such as fuzzy CSP, probabilistic CSP, max CSP, and weighted CSP. This exten...

A new rocket ignition mechanism developed at Utah State University, arc-track ignition, is very promising, but its underlying physics are poorly understood. An engineering/physics joint team was formed to investigate the process and suggest avenues for improvement of the technology. The objectives of the team evolved over the course of seven months of research. By the nature of this approach, u...

A data-drivcn approach is proposcd to rccognizc a family of planar ohjcc~s, which arc strctchcd along the axis of symmctry and arc partially ohscurcd, using hightuwaturc points, samplcd boundary distanccs (SBD) and a statistical mcthotl. cross correlation. In this work, thc SBD's arc thc distanccs mcasurcd to thc boundary points of an ohjcct from points cqually spaced along a linc which is cith...

Abstract—We present a trigonometric scheme to approximate a circular arc with its two end points and two end tangents/unit tangents. A rational cubic trigonometric Bézier curve is constructed whose end control points are defined by the end points of the circular arc. Weight functions and the remaining control points of the cubic trigonometric Bézier curve are estimated by variational approach t...

This paper presents a novel statistical approach for detecting breakpoints from chain encoded digital arcs. An arc point is declared as a breakpoint if the estimated orientations of the two fitted lines of the two arc segments immediately to the right and left of the arc point are significantly statistically different. The major contributions of this research include developing a method for ana...

ARC-520 Injection, an RNA interference drug for the treatment of hepatitis B that targets cccDNA-derived viral mRNA transcripts with high specificity, effectively reduces the production of viral proteins and HBV DNA. In this phase 1 randomized, double-blind, placebo-controlled study, 54 healthy volunteers (half male, half female) received a single, intravenous dose of 0.01-4.0 mg/kg ARC-520 Inj...