To study the variation rules of nonlinear stiffness double-row angular contact ball bearings (DR-ACBB), this paper proposed a general mathematic model for DR-ACBB under three different configurations based on improved quasi-static bearings, an explicit expression matrix is analytically derived, and double-layer nested iterative algorithm Newton–Raphson method designed to realize efficient solut...

The aim of this research work was to investigate on the ball filling estimation of Miduk semi-autogenous (SAG) Mill via an utilized method. Miduk copper concentrator is located in Kerman Province, Iran, and its size reduction stage includes one gyratory crusher which feeds one SAG mill (9.75 dia.(m)*3.88 length(m)) following two parallel ball mills (5dia.(m)*7lenght(m)). After SAG mill, a tromm...

The torque resistance of zirconia ceramic heads/titanium taper trunnion junctions was tested in accordance with ISO 7206-9:1994(E); using twelve modified heads of 32 mm diameter under representative physiological conditions. Test parameters studied included assembly force, vertical load during test (test load) and head length. Mean torque resistances measured were 8.9 N m for a 1 kN test load a...

Using  principle  of  minimum  total  potential  energy  approach  in conjunction  with  Rayleigh-Ritz  method,  the  electro-thermo- mechanical  axial  buckling  behavior  of  piezoelectric  polymeric cylindrical  shell  reinforced  with  double-walled  boron-nitride nanotube  (DWBNNT)  is  investigated. Coupling  between  electrical and mechanical  fields  are  considered  according  to  ...

The optimum designs are given for columns which are elastically clamped at both ends and under concentrated and distributed axial loads. The objective is to maximize the buckling load subject to volume and maximum stress constraints. The results for a minimum area constraint are also obtained for comparison. Under a distributed axial load, the stress constraint leads to different minimum cross-...

PURPOSE The purpose of this study was to compare the mechanical stability of three types of plate systems for opening wedge high tibial osteotomy. MATERIALS AND METHODS Forty-eight fresh frozen porcine tibia specimens were assigned to three different fixation device groups: Aescular group (16 specimens) was fixed with Aescular plates; Puddu group (16 specimens) with a Puddu plate, and TomoFix...

A pallet rack is a structure in which the beams and uprights are cold-formed steel sections. The beam-upright connections are normally clipped in order to select the beam levels required and for ease of assembly. For this reason, the uprights contain holes and perforations distributed along their length. The complexity of these components, with local, distortional and torsional/flexural bucklin...

The compressive behavior of tapered piles, particularly those with circular cross-sections, has been investigated during the last few decades. However, tensile such piles rarely studied in literature. In this paper, 12 static axial tests, comprising six and were performed on instrumented uniform cross-sections using a geotechnical centrifuge. Three had correspondingly circular, square, X-shaped...

Natural frequencies of a clamped axially loaded beam carrying an eccentric end rigid body are computed. A linearly varying non-follower axial force representing the beam’s own weight is taken into consideration. An analytical form of the frequency equation of the structure is obtained and solved numerically. The parameters associated with the end rigid body, the mass, the rotary inertia and the...

PURPOSE To investigate the effect of reducing tooth preparation and ceramic thickness on fracture resistance of lithium disilicate crowns. MATERIALS AND METHODS Specimen preparation included a standard complete crown preparation of a typodont mandibular left first molar with an occlusal reduction of 2 mm, proximal/axial wall reduction of 1.5 mm, and 1.0 mm deep chamfer (Group A). Another typo...