• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.9
• /
• pp.802-809
• /
• 2005

A hybrid genetic algorithm is proposed for the problem of generating laser torch paths to cut a stock plate nested with free-formed parts each having a set of sub-parts. In the problem, the total unproductive travel distance of the torch is minimized. The problem is shown to be formulated as a special case of the standard travelling salesman problem. The hybrid genetic algorithm for solving the problem is hierarchically structured: First, it uses a genetic algorithm to find the cutting path f3r the parts and then, based on the obtained cutting path, sequence of sub-parts and their piercing locations are optimally determined by using a combined genetic and heuristic algorithms. This process is repeated until any progress in the total unproductive travel distance is not achieved. Computational results are provided to illustrate the validity of the proposed algorithm.

• Journal of Korean Institute of Industrial Engineers
• /
• v.4 no.2
• /
• pp.77-81
• /
• 1978

The assortment problem with deterministic demand has been formulated so that a dynamic programming can be applied to find optimal production lengths that will minimize the sum of cutting losses. The original minimization problem can be reformulated as the maximization problem with a different objective function. This problem can be solved by the dynamic programming technique. A numerical example illustrates this approach. The ratio of computation amount of emumeration method to that of this dynamic programming is approximately n to 1.

• Journal for History of Mathematics
• /
• v.12 no.2
• /
• pp.25-39
• /
• 1999

In Euclidean plane geometry, areas of polygons can be computed through a finite process of cutting and pasting. The Hilbert's third problem is that a theory of volume can not be based on the idea of cutting and pasting. This problem was solved by Dehn a few months after it was posed. The purpose of this article is not only to study Hilbert's third Problem and its proof but also to provide basis for the secondary school mathematics.

• Transactions of Materials Processing
• /
• v.18 no.2
• /
• pp.166-171
• /
• 2009

In this paper, a basic study on micro cutting process with SM20C at low temperature environment was performed. In macro cutting fields, the cryogenic cutting process has been applied to cut the refractory metal but, the serious problem may be generated in micro cutting fields by the cryogenic environment. However, if the proper low temperature is applied to micro cutting area, the cooling effect of cutting heat is expected. Such effect can make the reduction of tool wear and burr formation. For verifying this possibility, the micro cutting experiment at low temperature was performed and SEM images were analyzed.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.3 no.4
• /
• pp.56-62
• /
• 2004

Using NC or CNC machine tool, the unmanned automatic production system has been growing recently in the manufacturing field. Thus it is important to find out the machinability of cutting force, tool wear and surface roughness during the cutting process. It is necessary to find how to estimate the machinability for the effective cutting condition because of problem about cutting power, tool wear, cutting time and precision. This study was planned to discover the relations of tool wear by variations of roughness and derived to correlate the wear with the surface roughness on the cutting parameter(cutting force, flank wear, surface roughness, friction angle, shear angle, slenderness ratio) when the aluminum alloy was cut in turning.

• Journal of Welding and Joining
• /
• v.27 no.6
• /
• pp.55-61
• /
• 2009

This study aims for determination of cutting work envelope of an articular robot for H-beam cutting. The robot has its own work envelope. The cutting of piece with groove requires the specific position of the torch which contracts the work envelope. This study suggested the new method to determine the cutting work envelope for this case. The method simplified the problem by use of the combination of inverse kinematics and forward kinematics. The method was used for cutting the H-beam with groove. The cutting work envelope was determined easily. The result was verified by 3D simulation system which implements the articular robot with 6 axes and the H-beam in the virtual shop.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.79-82
• /
• 1997

The current from the feed motor of a machine tool contains substantial information about the machining state. There have been many researches that investigated the current as a measure for the cutting forces. However it has not been reported that indirect measurement of the cutting forces from the current of the feed motor at rest is possible. The cutting force normal to the machined surface influences the machined surface of the workpiece, which makes it necessary to estimate this force to control the roughness of the machined surface. But the unpredictable behavior of the current prevents applying the current to prediction of the cutting state. In this paper, empirical approach was conducted to resolve the problem. Also parametric adaptive and fuzzy logic control strategies are applied to the force regulation problem. As a result, the current is shown to be related to the accumulation of the infinitesimal rotation of the motor, and besides the unpredictable behavior of the current is shown to be caused by the relationship. Subsequently the relationship between the current and the cutting force is identified, and it is presented that control of machined surface using the current of the feed motor at rest is possible.

• Structural Engineering and Mechanics
• /
• v.73 no.5
• /
• pp.501-513
• /
• 2020

In the present work, the optimization of machining parameters to achieve the desired technological parameters such as surface roughness, tool radial vibration and material removal rate have been carried out using response surface methodology (RSM). The hard turning of EN19 alloy steel with coated carbide (GC3015) cutting tools was studied. The main problem faced in manufacturer of hard and high precision components is the selection of optimum combination of cutting parameters for achieving required quality of surface finish with maximum production rate. This problem can be solved by development of mathematical model and execution of experiments by RSM. A face centred central composite design (FCCD), which comes under the RSM approach, with cutting parameters (cutting speed, feed rate and depth of cut) was used for statistical analysis. A second-order regression model were developed to correlate the cutting parameters with surface roughness, tool vibration and material removal rate. Consequently, numerical and graphical optimization were performed to obtain the most appropriate cutting parameters to produce the lowest surface roughness with minimal tool vibration and maximum material removal rate using desirability function approach. Finally, confirmation experiments were performed to verify the pertinence of the developed mathematical models.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.298-300
• /
• 2004

Arc-furnace facilities consume 9,895,165(MWh) which is about 69.6 Percent of electronic furnace power consumption. and interior of a country demand power have inclosed annual. but becaused of the problem of cost, power plant location, and environment have faced difficulty to electric power supply. In this paper, Examining Load cutting of Arc-furnace that is dominating high weight of industry electric power use. and it is expected to solve easily electric power supply and demand problem by highest Priority load cutting examination of Arc-furnace when electric power supply and demand problem happens to area electric power system when is urgent.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.11 no.2
• /
• pp.171-176
• /
• 2012

So far, carbide insert production technology was carried out using a diamond grinding wheel. This production technology has problem that raise production costs and decrease in productivity. The SIDE PRESS method to solve this problem have been developed. In this paper, the machining characteristics of lateral chip breaker turning inserts produced by the SIDE PRESS method was studied. The cutting force and the resulting surface roughness were measured at various cutting conditions. The experimental results indicate that the chip breaker inserts of three-dimensional geometry is the best cutting performance.