Original scientific paper Aiming at answering the questions of wear and failure of hob in the rock breaking process, the rock breaking process was simulated in different broken rock conditions by using finite element method. The relationship between normal force, lateral force, rolling force and time was obtained by rock breaking simulation analysis on the single edge disc cutter. The rock stre...

Presented in this article is a new accurate tool swept volume generation algorithm based on a generalized cutter for five-axis NC simulation and verification. Based on the surface envelope theory and the differential geometry, using analytical method, the strict deduction process of critical curve equation and swept envelope equation for generalized cutter are given. The motion feature of the c...

Presented in this article is a procedure for representing the cutterswept surface (CSS) of a generalized cutter in a single-valued form, ; =,f(x, v). The key idea is that the z-value of the CSS at a 2D point (x, y) is expressed as the sum of 1) the z-value at a point on the silhouette curve of the cutter bottom surface and 2) the incremental z-value along the cutter movement direction. Thus, th...

OBJECTIVE This prospective study was conducted to compare the clinical outcomes of a 6-row 3-D linear cutter with the standard 4-row linear cutter in patients who underwent elective gastrointestinal surgery anastomosis. METHOD Patients who underwent elective open gastrointestinal surgery that included stapled anastomosis using a linear cutter (Proximate®, Ethicon Endo-Surgery, Cincinnati, OH)...

In this paper, we describe a new geometric algorithm to determine the largest feasible cutter size for 2-D milling operations to be performed using a single cutter. In particular: 1. We give a general definition of the problem as the task of covering a target region without interfering with an obstruction region. This definition encompasses the task of milling a general 2-D profile that include...

silicon dioxide or silica is the earth’s most abundant mineral. the primary pulmonary illness attributable to silica exposure is silicosis, which is observed in three forms: classic, accelerated and acute. a case of silicosis is presented in this article who has been working in a stone-cutting plant. he had suffered from symptoms of silicosis one year after employment in this plant (acute form)...

For a cut ter suction dredger, exploring slurry formation mechanism plays an important role for improving the dredger’s efficiency and performance. In order to optimize the dredger’s working parameters, the flow field is simulated for the cutter head of a cutter suction dredger in this study. First, Cutter’s 3D model is const ructed by 3D Modeling software after necessary parameters are collect...

A new digital-based model is presented for the prediction cutting forces in 3-axis CNC milling of surfaces. The model uses an algorithm to detect the work-piece/cutter intersection domain automatically for given cutter location (CL), cutter and work-piece geometries. The algorithm uses a voxelization framework to voxelize the cutter helix as well as the work-piece and based on voxel intersectio...

The dynamic performances of head cutter for boom-type excavator were researched, and the corresponding dynamic equilibrium equations were derived. Based on the explicit dynamics analysis techniques of the Software ANSYS/LS-DYNA, transient dynamic analysis was carried out to simulate the cutting process of head cutter, and the main kinetic parameters were achieved. Finally, the cutting performan...

background: in radiation therapy, the sparing of normal tissues can be performed using either multi-leaf collimators or cerrobend blocks. the current work focuses on the physical characteristics of cerrobend blocks including attenuation coefficient, effective penumbra width and isodose curves undulation in penumbral regions. materials and methods: all measurements were performed using a dual en...