The prediction of rock sawability is important in the cost estimation and the planning of the stone plants. An accurate estimation of rock sawability helps to make the planning of the rock sawing projects more efficient. Rock sawability depends on non-controlled parameters related to rock characteristics and controlled parameters related to properties of cutting tools and equipment. In the same...

In this paper we investigate the behavior of mutation-based evolutionary algorithms on highly symmetric binary constraint satisfaction problems. With empirical methods we study why and when these algorithms perform better under the stepwise adaptive weighting of penalties (SAWing) than under the standard penalty function. We observe that SAWing has little effect when the local optima of the sym...

Hardwood sawmills traditionally saw logs in a manner that either orients sawlines parallel to the log central axis (straight sawing) or the log surface (allowing for taper). Sweep is characterized as uniform curvature along the entire length of a log. For logs with sweep, lumber yield losses from straight and taper sawing increase with increasing levels of sweep. Curve sawing logs with sweep wi...

Abstract Predicting the vibration of circular sawing machine is very important in examining performance process, as it shows amount energy consumption machine. Also, this factor directly related to maintenance cost, such that with a small increase level vibration, cost increases large extent. This paper presents new prediction models assess An evaluation model based on imperialist competitive a...

The cost of raw materials has a major role in the wood industry. From this point view, it is necessary to pay attention correct log-sawing pattern, which will optimize sawing process and increase quantity quality material as well. For measurements, we used beech (Fagus sylvatica L.). Beech L.) most common species Slovak Republic; total amount forests 34.8%. high frequency defects, such red fals...

In the classical approach, cutting forces and cutting power in sawing processes of orthotropic materials such as wood are generally calculated on the basis of the specific cutting resistance kc (cutting force per unit area of cut). For every type of sawing kinematics (frame saws, band saws and circular sawing machines) different empirical values of specific cutting resistance kc have to be appl...

A detailed approach to evaluate the sub-surface damage of diamond wire-sawn monocrystalline silicon wafers relating to the sawing process is presented. Residual stresses, the presence of amorphous silicon and microcracks are considered and related to diamond wire velocity and cutting ability. In particular, the degree of amorphization of the wafer surface is analyzed, as it may affect the etchi...

An assessment of wood workers' exposure to airborne cultivable bacteria, fungi, inhalable endotoxins and inhalable organic dust was performed at 12 sawmills that process mainly coniferous wood species. In each plant, samples were collected at four or five different work sites (debarking, sawing, sorting, planing and sawing cockpit) and the efficiency of sampling devices (impinger or filter) for...

Sawing by circular saw blades is predominant in the mechanized treatment of natural stone. The predictive sawing force crucial for optimizing, controlling, and monitoring process. In this work, a novel model predicting force, which based on distribution undeformed chip thickness at contact arc, was proposed. Based analysis geometry blade, segment surface divided into front end rear according to...