Circular features have been commonly used in numerous computer vision application areas for 3-D pose estimation. However, the estimation of such a feature’s pose from 2-D image coordinates results in an orientation-duality problem. Namely, although the 3-D position of the circle’s center can be uniquely identified, the solution process yields two different feasible orientations, of which only o...

Concentric circular antenna array (CCAA) has interesting features over other array configurations. A uniform arrangement of elements is assumed where the interelement spacing is kept almost half of the wavelength and the array parameters such as the steering matrix and gain are determined. The array performance such as beam power pattern, sidelobe level and beamwidth are discussed in two cases ...

DNA hemicatenanes, one of the simplest possible junctions between two double stranded DNA molecules, have frequently been mentioned in the literature for their possible function in DNA replication, recombination, repair, and organization in chromosomes. They have been little studied experimentally, however, due to the lack of an appropriate method for their preparation. Here we have designed a ...

Viroids are small autonomously replicating RNAs that share structural features with other subviral circular single-stranded RNAs of plants. Viroids and other circular single-stranded RNAs can be synthesised in vitro by a PCR-based procedure using a simple set of reactions. Two end-to-end primers are selected from a desired region of the viroid, one for the synthesis of the first strand cDNA and...

Development in China SHI Lei*, XING Lu*, BI Jun*, ZHANG Bin* *) State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University; Center for Environmental Management and Policy, Nanjing University and Jiangsu Environmental Production Department, Nanjing 210093, P. R. China ABSTRACT Circular economy is a theory which advocates developing economy on the basi...

The traditional 3 3 cell neighborhood used in a focal operation on a raster layer has a square shape that results in a dimensional neighborhood of which the orientation is eventually arbitrary to the physical features represented. This paper presents an experiment using a circular neighborhood to calculate slope gradient. Comparisons of the results from a circular neighborhood with the results ...

Qanats in northern Xinjiang of China provide valuable information for agriculturists and anthropologists who seek fundamental understanding of the distribution of qanat water supply systems with regard to water resource utilization, the development of oasis agriculture, and eventually climate change. Only the tops of qanat shafts (TQSs), indicating the course of the qanats, can be observed from...

BACKGROUND The development of new surgical instruments and devices has facilitated the performance of esophagojejunostomy after total gastrectomy. However, total prevention of dehiscence of anastomoses remains difficult. We introduced a new procedure for esophagojejunostomy using a circular stapler, requiring sacrifice of only a small part of the jejunum. METHODS The study group comprised 390...