The size and length effects of an inclusion on multi-pass copper shaped-wire drawing were investigated. For this purpose, an experimental investigation on optimal die half-angle was conducted. Based on experimental data of optimal die half-angle, wire and inclusion deformations, drawing and hydrostatic stress of copper shaped-wires that contain an inclusion were calculated by two-dimensional fi...

The proof simply consists in computing the fundamental group of the complement X of W in R3 and checking that the class of r in π1(X) is not 1. The first step means finding a presentation of π1(X). This could quickly be achieved using the Wirtinger presentation, but I prefer to give a more self-contained proof, using only van Kampen’s theorem. Let W1 be the wire obtained from W by adding to it ...

The effects of steel wire patenting process parameters on very fine interlamellar spacing in the pearlitic steel wire were investigated and the optimized condition of the process was achieved. In this work, the initial nanopearlitic structure was obtained in a 0.72 wt% carbon steel wire before the wire drawing process. The results were the minimum interlamellar spacing of 35 nm and maximum ulti...

the key to successful long-term peritoneal dialysis (pd) is permanent and safe access to peritoneal cavity. the two most commonly used tenckoff catheters for pd are the straight and coiled catheters. the present study was undertaken to assess the catheter survival, catheter associated infections, and all cause mortality and to compare the straight with coiled catheters in pd. during april 1997-...

The straight skeleton of a simple polygon is defined as the trace of the vertices when the initial polygon is shrunken in self-parallel manner [2]. In this paper, we propose a simple algorithm for drawing the straight skeleton of a monotone polygon. The time and space complexities of our algorithm are O(nlogn) and O(n) respectively.

in this study, as for the re-casting, surface alloying and re-solidification layer of this alloys at the work piece level machining with wire electro discharge machining (wedm), changes of surface micro hardness with changes of operational parameters has been studied. therefore, study shows using surface alloying phenomena with the diffusion of wire material into the machined surface and select...