We construct analytically, a new family of null solutions to Maxwell's equations in free space whose field lines encode all torus knots and links. The evolution of these null fields, analogous to a compressible flow along the Poynting vector that is shear free, preserves the topology of the knots and links. Our approach combines the construction of null fields with complex polynomials on S3. We...

During arthroscopic knot tying, one of the suture limbs may break before completion of the knot. With a single suture limb left, it may not be possible to secure the knot against slipping, and the surgeon may be forced to use an additional anchor to obtain a secure repair. We present a tool and method that allow completion of the knot on a single suture limb. Alternatively, the method can be us...

Low-cost recognition systems based on hidden Markov models (HMM) for mobile speech recognizers (mobile phones, PDAs) have a limited quantity of memory and processing power. Furthermore, the resources have to be shared between several applications. In this paper memory efficient HMMs were investigated for low-cost recognition platforms. The feature parameter tying HMM and subspace distribution c...

How to effectively recognize English letters spoken by Chinese people is our major concern in the paper. Some efforts are made to build Chinese extended Initial/Final (XIF) based HMMs for English alphabet recognition which can be integrated with large vocabulary continuous Chinese speech recognition (Chinese LVCSR) system based on a same XIF set. The alphabet-specific XIF HMMs are built using c...

Objective skill assessment-based personal performance feedback is a vital part of surgical training. Either kinematic—acquired through robotic systems, mounted sensors on tooltips or wearable sensors—or visual input data can be employed to perform objective algorithm-driven assessment. Kinematic have been successfully linked with the expertise surgeons performing Robot-Assisted Minimally Invasi...