This paper presents a template-based vision system to detect and classify the nonuniformaties that appear on the semiconductor wafer surfaces. Design goals include detection of flaws and correlation of defect features based on semiconductor industry expert’s knowledge. The die pattern is generated and kept as the reference beforehand from the experts in the semiconductor industry. The system is...

In this paper, a method for utilizing knot information from computed tomography (CT) scanning of Scots pine (Pinus sylvestris L.) logs was evaluated. A high speed industrial CT scanner is being developed, which will enable scanning of logs in sawmills at production speed. This development calls for the ability to optimize breakdown parameters in a quick manner because there are many decisions t...

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...

Curve sawing is a technique used more and more widely in lumber mills in order to obtain more commercially valuable pieces from a given log. It is important to understand and know this technique in order for it to be used optimally. This article deals with the mathematical modeling of curve sawing, so that a module pertaining to curve sawing can be incorporated into the Optitek software, which ...

The paper deals with the sawing simulation of Maritime pine (Pinus pinaster Ait.) and is a report from a project aiming to increase the knowledge in how different raw material characteristics and sawing factors are affecting on the sawing yield of Maritime pine. The conversion was executed by an integrated optimising software system, WooDCIM® developed at VTT Technical Research Centre of Finlan...

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...

Accurate sawing requires attention to proper alignment and maintenance. Alignment is critical to modern sawmills using thin kerf saws. In fact, the improvements in machine design were critical to the development of thin kerf sawing systems. About two-thirds of sawing problems are caused by misalignment, not saw preparation. Good alignment reduces down-time and machinery wear and should be part ...

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...

In rural, isolated areas, sawmills are often equipped with one or more small-capacity hand-fed band saws. Even in this situation, the productivity of saw must be viewed through factors that influence it, namely characteristics logs and optimization stages activities carried out. Therefore, time consumption, structure working recovery rate sawing into lumber provide important information for use...