gravity acceleration data have grand pursuit for marine applications. due to environmental effects, marine gravity observations always hold a high noise level. in this paper, we propose an approach to produce marine gravity data using satellite altimetry, high-resolution geopotential models and harmonic splines. on the one hand, harmonic spline functions have great capability for local gravity ...

We review the development and status of GPS geodetic methods for high-precision global time and frequency comparisons. A comprehensive view is taken, including hardware effects in the transmitting satellites and tracking receiver stations, data analysis and interpretation, and comparisons with independent results. Other GPS techniques rely on single-frequency data and/or assume cancellation of ...

The landmark black hole images recently taken by the Event Horizon Telescope (EHT) have allowed detailed study of immediate surroundings supermassive holes (SMBHs) via direct imaging. These tantalizing early results motivate an expansion array, its instrumental capabilities, and dedicated long-term observations to resolve track faint dynamical features in jet accretion flow. next-generation (ng...

Background: Polymethylmethacrylate antibiotic impregnated beads can be an effective treatment for chronicosteomyelitis or an adjuvant in the treatment of open fractures. It remains unclear however whether the beads causelong-term adverse events if not removed. The purpose of this study was to determine if removal of antibiotic beads wasrequired in order to avoid long term comp...

It is well known that multipath disturbance is one of the major error sources impacting on high precision GPS positioning. The multipath disturbance is largely dependent on the receiver’s environment since satellite signals can arrive at the receiver via multiple paths, due to reflections from nearby objects such as trees, buildings, vehicles, etc. Although the multipath effect can be reduced b...

BACKGROUND AND OBJECTIVES Laparoscopic transcystic common bile duct exploration (LTCBDE) is a complex procedure requiring expertise in laparoscopic and choledochoscopic skills. The purpose of this study was to investigate the safety and feasibility of treating biliary calculi through laparoscopic transcystic exploration of the CBD via an ultrathin choledochoscope combined with dual-frequency la...