• Journal of the Korean Society for Precision Engineering
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• v.21 no.7
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• pp.145-152
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• 2004

This paper proposed efficient manufacturing system using the OMM (on-machine measurement) system. The OMM system is software based 3D modeler for inspection on machine and it is interfaced tool machine with RS232C. The software is composed of two inspection modules that one is touch probe operating module and the other is laser displacement sensor operating module. The module for touch probe has need of inspection feature that extracted it from CAD data. Touch probe moves to workpiece by three operating modes as follows: manual, general and automatic mode. The operating module of laser displacement sensor is used inspection for profile and very small hole. An Advantage of this inspection method is to be able to execute on-line inspection during machining or after it. The efficiency of proposed system which can predict and definite the machining errors of each process is verified, so the developed system is applied to inspect the mold-base(cavity, core).

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.1
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• pp.93-100
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• 1994

5-axis CNC machining is being used in the manufacturing of tire mold, screw, and turbine blade because it can produce complex workpiece more efficiently and accurately than 3-axis CNC machining does. However, it is difficult to calculate the CL data in 5-axis CNC machining. This paper describes an efficient method to modify and edit the NC code and a data structure for representation of the workpiece produced by 5-axis CNC machining. Wireframe display of tool path and shading display of workpiece are used to represent verification results. Machining errors can be evaluated quantitively using the data structure based on the workpiece data model. The methods are implemented in a program with a IBM-PC and MS-Windows.

• Journal of the Korean Society of Industry Convergence
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• v.13 no.2
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• pp.107-112
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• 2010

The automation and Cell-Line of manufacturing process are going to be new trend in the industry spot. But workers bodily burden by manual labour is still doing repeatedly at many processes. It is appearing to workers bodily burden (Shoulder, waist, hand, wrist, leg) with repeating works at assembly line which is from the static working space. The analysis with 6 Sigma Tool at specific standard assembly line improve the point at issue for unsuitable items and analyzed objects. Physical pain of worker is solved by the improvement action for the factor of 7 items with the result of analysis. It was known to be improved by solving of workers burden related to the change of 6 Sigma level from 2.16 to 4.1 at assembly line.

• Design & Manufacturing
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• v.14 no.4
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• pp.40-45
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• 2020

In a vehicle-to-vehicle accident, the impact posture, braking status, final stopping position, collision point and collision speed are important factors for accident reconstruction. In particular, the speed of collision is the most important issue. In this study, the collision speed and the final stopping position in the tunnel were estimated using PC-CRASH, a vehicle crash analysis program used for traffic accident analysis, and the final stopping position of the simulation and the final stopping position of the traffic accident report were compared. When the Pride speed was 0km/h or 30km/h and the Sorento speed was 100m/h, the simulation results and reports matched the final stopping positions and posture of the two vehicles. As a result of the simulation, it can be estimated that Pride was collided in an almost stationary state.

• Design & Manufacturing
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• v.15 no.2
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• pp.17-22
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• 2021

The shape of the blank greatly affects the formability and quality of the product after the stamping process. In this study, the geometry of the B-Pillar blank in the stamping process was optimized using design of experiments. The geometry of the blank for the B-pillar was simplified with the two length values and two radius values. The effects of design variables were studied through the Design of experiments. The stamping process of the B-pillar was predicted with the Finite Element Analysis (FEA). The optimized blank geometry was obtained. It results in the reduced maximum equivalent plastic strain. The local necking and the wrinkling did not occurred with the optimized blank geometry.

• Design & Manufacturing
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• v.15 no.2
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• pp.49-55
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• 2021

In this study, CALPUFF, a three-dimensional atmospheric diffusion model, was used to predict the degree of influence of pollutants generated during clean center operation on surrounding areas. To drive the CALPUFF model, CALMET, a weather field calculation model, was used. Due to the influence of the wind field, air pollutants from the Clean Center diffused in the southeast direction, increasing the distribution area. SOx satisfies atmospheric environmental standards with an annual average value of 0.02 ppm or less NOx satisfies atmospheric environmental standards with an annual average value of 0.03 ppm or less. Dust (PM-10) satisfies atmospheric environmental standards with an annual average value of 50㎍/m³ or less and 24 hours average value of 100㎍/m³ or less. CO satisfies atmospheric environmental standards with an 8 hours average value of 9 ppm or less and an 1 hour average value of 25 ppm or less.

• Design & Manufacturing
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• v.15 no.2
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• pp.36-41
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• 2021

The 3 dimensional Pipe (Annular) Shaped Products was selected as a test sample, then a attribute of a molding shrinkage according to the parameters of a injection process was examined with PC, which is the typical engineering plastic. Both the inside and the outside diameter of the Pipe (Annular) sample were shrank into the inner direction of the part. And then the comparative analysis of the samples proved that a increasing thickness led a bigger shrinkage rate in the equal outside diametric samples, and a decreasing outside diameter caused a bigger shrinkage rate in the same thickness samples. The comparative study of the cushion volume of a injection machine showed that the molding shrinkage was most affected by the pressure strength among the resin temperature, the maintenance pressure strength and the maintenance pressure duration time. Each of the shrinkage rates according to the measuring direction and the gate position was different. As a result, the injection molded sample had not a typical circular shape.

• Design & Manufacturing
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• v.14 no.4
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• pp.1-10
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• 2020

The seal plays a role in preventing oil leakage when the lip and the rotating shaft come into contact with the fluid and air pressure. Recently, micro dimples or micro pockets are processed and used on the lubrication surfaces of thrust bearings, mechanical bearings, and piston rings. Compared to a smooth surface, micro dimples reduce friction and increase the life of parts. This paper analyzed various kinds of micro dimple shapes on the sealing surface, i.e. circle, rectangle, triangle, and trapezoid. For this purpose, Introduced the design of experiments to work out a micro dimple configuration, unlikely to be damaged from cracks and low in contact stress. As a result, the triangular dimple showed the best results. Optimal factors were dimple size 0.15 mm, dimple depth 0.0383 mm, dimple density 40%, and the maximum equivalent stress was 9.1455 MPa, and the maximum contact pressure was 9.6612 MPa. This paper analyzed the optimal shape of dimples by finite element analysis. As a research project, experiments and comparative analysis of micro dimple shapes are needed.

• Design & Manufacturing
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• v.16 no.1
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• pp.15-20
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• 2022

This paper is about elimination the situation in which gas sensor data becomes inaccurate due to temperature control when a semiconductor gas sensor is driven. Recently, interest in semiconductor gas sensors is high because semiconductor sensors can be driven with small and low power. Although semiconductor-type gas sensors have various advantages, there is a problem that they must operate at high temperatures. First temperature control was configured to adjust the temperature value of the heater mounted on the gas sensor. At that time, in controlling the heater temperature, gas sensor data are fluctuated despite supplying same gas concentration according to the temperature controlled. To resolve this problem, gas and temperature are extracted as a data. And then, a relation function is constructed between gas and temperature data. At this time, it is included low pass filter to get the stable data. In this paper, we can find optimal gain and parameters between gas and temperature data by using genetic algorithm.

• Design & Manufacturing
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• v.16 no.3
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• pp.34-38
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• 2022

Regular expression pattern matching is widely used in applications such as computer virus vaccine, NIDS and DNA sequencing analysis. Hardware-based pattern matching is used when high-performance processing is required due to time constraints. ReCPU, SMPU, and REMP, which are processor-based regular expression matching processors, have been proposed to solve the problem of the hardware-based method that requires resynthesis whenever a pattern is updated. However, these processor-based regular expression matching processors inefficiently handle repetitive operations of regular expressions. In this paper, we propose a new instruction set to improve the inefficient repetitive operations of ReCPU and SMPU. We propose REMPi, a regular expression matching processor that enables efficient iterative operations based on the REMP instruction set. REMPi improves the inefficient method of processing a particularly short sub-pattern as a repeat operation OR, and enables processing with a single instruction. In addition, by using a down counter and a counter stack, nested iterative operations are also efficiently processed. REMPi was described with Verilog and synthesized on Intel Stratix IV FPGA.