LEE, SUNG WON. A Probability Model for Random Fiber Breakage. (Under the direction of JOHN WILLIAM BISHlR). Two fundamental questions in connection with the random breakage of fibers in a breakage system are set forth: Given a fiber group of any particular length, (1) What is the probability that a fiber of the length groups breaks at all? (2) What is the probability that a fiber breaks into s ...

Vertical roller mills (VRMs) are well-established grinding equipment for various tasks in the coal and cement industry. There are few studies on simulation of VRMs. In this research work, application of perfect mixing model for simulation of a VRM in a cement grinding plant was investigated. Two sampling surveys were carried out on the VRM circuit. The samples and data from the first survey wer...

Abstract A large part of the energy introduced during grinding is converted into heat. As not all heat can be dissipated by cooling lubricant, thermally induced displacements in machine components occur. These have a negative influence on component quality. Since wheel topography changes process due to wear, wear mechanisms grain splintering, breakage as well abrasion were identified and quanti...

in this paper shear behavior of two calcareous sands having different physical properties areinvestigated using drained and undrained triaxial tests. the investigated sands are obtained from two differentzones located in persian gulf, kish island and tonbak region. analysis based on energy aspects show thatfriction angle in these soils, having crushable particles, is formed of three components:...

In This Issue In This Issue Saying NO to muscular dystrophy ccording to the prevailing model for Duchenne muscular dystrophy (DMD) pathogenesis, a lack of dystrophin protein makes muscle cells susceptible to mechanical damage, leading to muscle breakdown. On page 123, Wehling et al. suggest that the major damage in DMD may actually be caused by a secondary consequence of dystrophin loss: destru...

In soil mechanics, student's models are classified as simple models that teach us unexplained elements of behaviour; an example is the Cam clay constitutive models of critical state soil mechanics (CSSM). 'Engineer's models' are models that elaborate the theory to fit more behavioural trends; this is usually done by adding fitting parameters to the student's models. Can currently unexplained be...

Abnormally high levels of spontaneous and mitomycin C or diepoxybutane induced chromosome breakage were observed in lymphocytes from eight out of nine previously undescribed patients clinically diagnosed as having Fanconi's anaemia. The results suggest that the combination of spontaneous and induced chromosome breakage is a good aid in the differential diagnosis and we suggest that increased ch...

Literature dealing with the mechanisms of hair breakage in combing and brushing published so far has been reviewed as a background for the critical evaluation of the method and data analysis of the paper “Statistical Analysis of Hair Breakage. II” by Evans and Park (1). Accumulated knowledge about hair breakage in these grooming processes indicates that hair breakage in combing and brushing res...

The granulometric range used has a direct influence on the life of ballast layer when subjected to load generated by rail traffic. However, in Brazil, we have only two size ranges be used. publications related subject matter under study express need for continuous grain strip, different from ones usually our railways. This more band would provide less deformation and reduction degradation, gran...