Cutting stock problems are within knapsack optimization problems and are considered as a non-deterministic polynomial-time (NP)-hard problem. In this paper, two-dimensional cutting stock problems were presented in which items and stocks were rectangular and cuttings were guillotine. First, a new, practical, rapid, and heuristic method was proposed for such problems. Then, the ...

Last years analytical or finite element models of milling become more efficient and focus on more physical aspects, nevertheless the milling process is still experimentally unknown on a wide range of use. This paper propose to analyse with accuracy milling operations by investigating the cutting forces values, shape of cutting forces curves obtained for different cutting speeds, and related phe...

OBJECTIVE The aim of this study was to quantify the surface area, volume and specific surface area of endodontic files employing quantitative X-ray micro computed tomography (mXCT). MATERIAL AND METHODS Three sets (six files each) of the Flex-Master Ni-Ti system (Nº 20, 25 and 30, taper .04) were utilized in this study. The files were scanned by mXCT. The surface area and volume of all files ...

In this research work a series of tests were conducted in order to determine flank wear and cutting force FY on hard AISI 440 C martensitic stainless steel and SCM 440 alloy steels. The operating parameters are cutting speed, feed rate and a constant depth of cut to investigate the flank wear and cutting force. No cutting fluid was used during the turning process. The cutting tool used was CBN ...

The application of conventional cutting fluids in machining operations is harmful and not eco-friendly. In this context, the present work focuses on environmental friendly cutting fluids such as vegetable oil based cutting fluids (VBCFs). The objective of this work is to determine the influence of vegetable oil based cutting fluids (sesame and coconut oil) with extreme pressure (EP) additive on...

abstract an investigation was accomplished during 2007 and 2008 to test effect of hormonal treatment and cutting position on rooting of sebri , shekari and natanz cultivars of pear (pyrus pyrifolia.) the experimental design was a two way factorial in a completely randomized method and with pgr5 treatment (iba and iba with naa in four levels in the first year and four higher levels of iba in sec...

Niobium based super alloys are an unusual class of metallic materials with an exceptional combination of high temperature strength, toughness, and resistance to degradation in corrosive or oxidizing environments. The focus of present work was to study the effect of cutting parameters – speed, feed and depth of cut on the machinability of Niobium C-103 under dry machining condition using respons...

Abstract Lumbar puncture (LP) procedures are commonly performed for diagnostic purposes by neurologists and emergency physicians, intrathecal local anesthesthetic administration spinal anesthesia anesthesiologists. Complications include post-dural headache, meningitis, epidural hematoma neurological injury. A recent article Ertas et al in the Journal of Clinical Neurology Neurosurgery highlight...

This paper presents the performance evaluation of three different cutting fluids used in a minimal quantity lubrication (MQL) system. The MQL system, developed in-house at the University of Malaya, was capable of delivering high velocity cutting fluid in narrow pulsed jet forms at a rate of 2 ml/min and a pressure of 20 MPa. The three cutting fluids chosen were neat oil, soluble oil and semi-sy...