Dynamic calibration for multi-beam bathymetric system based on characteristic data processing
The geometric installation error of the multi-beam bathymetric system will affect measure accuracy of the depth and location, which must be faced and resolved in the engineering survey urgently. The most important three kinds of the installation error are roll error, pitch error and yaw error. Through quantitative analysis of impact of installation error to the measure result, a dynamic calibration method has been proposed in the paper. In the method, installation errors can be obtained by analyzing bathymetric result from the characteristic terrain seafloor and the errors will be used as the parameters to calibrate other bathymetric result. Validity of the method has been proved by processing the measure data from Songhua Lake test.
Research and Implementation of Real-time Roll Compensation Technology for Multi-beam Bathymetric System
The ship roll influences the measurement of multi-beam, the movement of ship lead to the swath is not uniform. In order to cover wider sea areas, one approach is to improve the overlap rate of adjacent area. However, this approach has a defect that decreases the measurement efficiency. In this paper, the method of real-time compensation technology was adopted to increase the measurement efficiency. According to roll angle, real-time calculate the beam angle, each measurement has stationary beam angle compare with land coordinate system, and the swath is uniform, in the case of full coverage, the overlap rate of adjacent area would reduce, therefore, measurement efficiency is improved. In the process of real-time roll implementation, due to the slow change rate of roll and the complicated calculation for beam angle, hence the NIOS II was presented. However, the forming of beam directly connect with sample points, demanding real-time, hence the FPGA logic was presented. Take the advantage of real-time calculation and decrease the demand of logic resource properties, demonstrated that this approach could increase the measurement efficiency.
Mucoadhesive Nanoparticles for Drug Delivery to the Anterior Eye
While the use of topical drops for the delivery of drugs to the anterior of the eye is well accepted, it is far from efficient with as little as 5% of the drug instilled on the eye actually reaching the target tissue. The ability to prolong the residence time on the eye is desirable. Based on the acceptability of 2-hydroxyethyl methacrylate based polymers in contact lens applications, the current work focuses on the development of a poly(2-hydroxyethyl methacrylate (HEMA)) nanoparticle system. The particles were modified to allow for degradation and to permit mucoadhesion. Size and morphological analysis of the final polymer products showed that nano-sized, spherical particles were produced. FTIR spectra demonstrated that the nanoparticles comprised poly(HEMA) and that 3-(acrylamido)phenylboronic acid (3AAPBA), as a mucoadhesive, was successfully incorporated. Degradation of nanoparticles containing N,N′-bis(acryloyl)cystamine (BAC) after incubation with DL-dithiothreitol (DTT) was confirmed by a decrease in turbidity and through transmission electron microscopy (TEM). Nanoparticle mucoadhesion was shown through an in-vitro zeta potential analysis.