machining operation is one of the most applicable processes for the manufacturing of industrial parts. usually, the quality of finished part in turning operation is measured in terms of surface roughness. in turn, surface quality is determined by machining parameters and tool geometry specifications. the main objective of this study is to model and optimize machining parameters and tool geometr...

background: the aim of this study was to investigate vertebral geometry changes and determine cutoff value of vertebral height to predict fractures. methods: in a cross-sectional study, 280 postmenopausal women recruited .in all subjects bone mineral density and radiog raphy of the lumbar spine performed. lateral radiographs were evaluated for identification of vertebral fractures, using a vali...

the potential energy surface of gaseous glycine determined years ago in the ab initio b3lyp/6-311++g** calculations is composed of thirteen stable conformers. we performed the ab initiomolecular orbital calculations as the starting point to carry out a force field and normal coordinatecalculation on the most stable conformer of non-zwitterionic glycine [conformer (i)]. thecalculations were carr...

This paper proposes a classification of three-revolute orthogonal manipulators that have at least one of their DH parameters equal to zero. This classification is based on the topology of their workspace. The workspace is characterized in a half-cross section by the singular curves. The workspace topology is defined by the number of cusps and nodes that appear on these singular curves. The mani...

Additive Manufacturing describes the technologies that can produce a physical model out of a computer model with a layer-by-layer production process. Additive Manufacturing technologies, as compared to traditional manufacturing methods, have the high capability of manufacturing the complex components using minimum energy and minimum consumption. These technologies have brought about the possibi...

A classification of a family of 3-revolute (3R) positioning manipulators is established. This classification is based on the topology of their workspace. The workspace is characterized in a half-cross section by the singular curves of the manipulator. The workspace topology is defined by the number of cusps and nodes that appear on these singular curves. The design parameters space is shown to ...

The radiative neutron capture on lithium-7 is calculated model independently using a low energy halo effective field theory. The cross section is expressed in terms of scattering parameters directly related to the S-matrix element. The cross section depends on the poorly known p-wave effective range parameter r1. This constitutes the leading order uncertainty in traditional model calculations. ...

one of the most important challenges in the development of urban railways network is the effects of railway vibrations on human and adjacent structures. although various investigations into the sources of railway vibrations have been conducted, very few research works have been reported on the influences of track geometry parameters on the level of vibrations. this is addressed in this research...