INTRODUCTION A successful total knee arthroplasty (TKA) is dependent on many factors, but component alignment is particularly critical. Aligning the femoral component parallel to the transepicondylar axis is generally regarded as the optimal rotational position, since it has been shown to produce a balanced joint, optimize patellar tracking, and minimize patellofemoral shear forces [1,2] the fe...

The hydrological catchment areas are commonly extracted from digital elevation models (DEMs). The shortcoming is that computations for large areas are very time consuming and even may be impractical. Furthermore, the DEM may be inaccessible or in a poor quality. This chapter presents an algorithm to approximate the medial axis of river networks, which leads to catchment area delineation. We pro...

Medial representations have been widely used for many shape analysis and processing tasks. Large and complex 3D shapes are, in this context, a challenging case. Recently, several methods have been proposed that extract point-based medial surfaces with high accuracy and computational scalability. However, the resulting medial clouds are of limited use for shape processing due to the difficulty o...

The main subject of this chapter is an application of an extended version of the polygonal line algorithm to hand-written character skeletonization. Skeletonization is one of the important areas in image processing. It is most often, although not exclusively, used for images of hand-written or printed characters so we describe it here in this context. When we look at the image of a letter, we s...

The pocketing operation is a fundamental procedure in NC machining. Typical pocketing schemes compute uniform successive offsets or parallel cuts of the outline of the pocket, resulting in a toolpath with C discontinuities. These discontinuities render the toolpath quite impractical in the context of high speed machining (HSM). This work addresses and fully resolves the need for a C continuous ...

An algorithm is presented for reconstructing a quadtree from its quadtree medial axis transform (QMAT). It is useful when performing operations for which the QMAT is well suited (e.g., thinning of an image). The algorithm is a postorder tree traversal which propagates the subsumption of each BLACK QMAT node in the eight possible directions. Analysis of the algorithm shows that its average execu...

Previous experimental studies (e.g. Kovacs I, Julesz B. Nature (London) 1994; 370:644-646) have found enhanced contrast sensitivity at medial locations, supporting theoretical speculations that the visual system represents simple spatial regions by their medial axes. The core model (Burbeck CA, Pizer SM. Vis Res 1995;35:1917-1930) hypothesizes that the medial representation arises in a scale-sp...

Load balanced routing is a long standing yet challenging problem. Despite many years’ of work there is still a gap between theoretical research and practical algorithms. The main contribution in this paper is to bridge the gap and provide rigorous analysis of a practically interesting algorithm for routing in a large scale sensor network of complex shape – routing by using the medial axis of th...

Thinning of character images is a big challenge. Removal of strokes or deformities in thinning is a difficult problem. In this paper, we have proposed a medial axis based thinning strategy used for performing skeletonization of printed and handwritten character images. In this method, we have used shape characteristics of text to get skeleton of nearly same as the true character shape. This app...