• Journal of the Semiconductor & Display Technology
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• v.10 no.3
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• pp.99-103
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• 2011

The stereoscopic vision system is the algorithm to obtain the depth of target object of stereo vision image. This paper presents an efficient disparity matching method using blue edge filter and graph cut algorithm. We do recommend the use of the simple sobel edge operator. The application of B band sobel edge operator over image demonstrates result with somewhat noisy (distinct border). The basic technique is to construct a specialized graph for the energy function to be minimized such that the minimum cut on the graph also minimizes the energy (either globally or locally). This method has the advantage of saving a lot of data. We propose a preprocessing effective stereo matching method based on sobel algorithm which uses blue edge information and the graph cut, we could obtain effective depth map.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.685-690
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• 2000

In this study relationship between relief angles and chatter vibration in turning was examined by using the direct cutting test, in which the cutting depth of a tapered workpiece is varied continuously and the limiting depth of cut is measured at the time when chatter occurs. Test results reveal that 1) limiting depth of cut increases is proportion to side relief angles between 0$^{\circ}$ and 3$^{\circ}$, 2) limiting depth of cut does not show any evident change in spite of side relief angle increased from 3$^{\circ}$ to 12$^{\circ}$, 3) also limiting depth of cut does not change despite front angle change from 0$^{\circ}$ to 12$^{\circ}$.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.8
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• pp.126-133
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• 2002

The cutting thickness of ultra-precision machining is generally very small, only a few micrometer or even down to the order of a few nanometer. In such case, a basic understanding of the mechanism on the micro-machining process is is necessary to produce a high quality surface. When machining at very small depths of cut, metal flow near a rounded tool edge become important. In this paper a finite element analysis is presented to calculate the stagnation point on the tool edge or critical depth of cut below which no cutting occurs. From the simulation, the effects of the cutting speed on the critical depths of cut were calculated and discussed. Also the transition of the stagnation point according to the increase of the depths of cut was observed.

• Korean Journal of Optics and Photonics
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• v.20 no.1
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• pp.16-22
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• 2009

We propose a method to convert a two-dimensional movie to a three-dimensional movie using normalized cut and optical flow. In this paper, we segment an image of a two-dimensional movie to objects first, and then estimate the depth of each object. Normalized cut is one of the image segmentation algorithms. For improving speed and accuracy of normalized cut, we used a watershed algorithm and a weight function using optical flow. We estimate the depth of objects which are segmented by improved normalized cut using optical flow. Ordinal depth is estimated by the change of the segmented object label in an occluded region which is the difference of absolute values of optical flow. For compensating ordinal depth, we generate the relational depth which is the absolute value of optical flow as motion parallax. A final depth map is determined by multiplying ordinal depth by relational depth, then dividing by average optical flow. In this research, we propose the two-dimensional/three-dimensional movie conversion method which is applicable to all three-dimensional display devices and all two-dimensional movie formats. We present experimental results using sample two-dimensional movies.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.1
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• pp.85-91
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• 2003

The experimental study for turning circular free fanned surface with TiN coated insert tool was conducted for different cutting conditions such as cutting speed, feed rate and depth-of-cut. For the fluctuation of 1.0mm depth-of-cut, the characteristics for machined surface and tool wear were less influenced by the feed rate and cutting speed than those of higher depth of cut. The higher surface roughness and surface precision were obtained in lower cutting speed. For the fluctuation of 1.5mm depth-of-cut, the higher surface roughness was obtained for the case of the lower feed rate of 0.05-10mm/rev and the higher cutting speed of 80m/min. For the fluctuation of 2.0mm depth-of-cut, the surface roughness and surface precision were too worse to machine the specimen And the flank wear on the tool was increased rapidly rather than the crater wear.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.21-27
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• 1997

This paper aims to clarify the effects of grinding conditions in form grinding of Sr-ferrite with the electro-plated diamond wheel. The main conclusions obtained were as follows. (1) The flexural strength and surface roughness of ferrite became the best at the peripheral wheel speed of 1700 m/min. (2) In the case of the depth of cut larger than 0.4mm, crack layers is induced in the ground surface, and the fracture type of chips exhibits slight ductile mode in the depth of cut smaller than 0.2mm. (3) Whe the depth of cut exceeds 0.6mm, the wheel life becomes extremely severe due to the large chipping and brack- age in the diamond grains. However, at the depth of cut .leq. 0.05mm, the diamond grain shows abrasive wear. (4) The decrease of flexural strength and the increase of surface roughness is in proportion to the increase of the feed rate. (5) Most effective nozzle setting angles with various delivery conditions of the grinding fluid, such as nozzle position .PHI. , flow rate Q, etc., were made clear.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.5
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• pp.62-66
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• 2004

A study for investigating the effects of the cutting conditions(feed rate, radial depth of cut, cutting speed) and the tool diameter on the circumferential geometry of the cyl indrically end-mi1led workpiece is described. In this work, the circumferential geometry is characterized by the roundness error. Experimental results show that the circumferential geometry is directly affected by the material removal per tooth,which is defined as a function of the cutting speed, the feed rate and the radial depth of cut. And, the radial depth of cut is revealed to be the most critical condition among them. It is also found that the roundness error decreases when the tool diameter is larger under the same cutting conditions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.29-33
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• 1996

This paper aims to clatify the potimum grinding condition for the electroplated diamond wheel in form grinding of Sr-ferrite. The main conclusions obtained were as follows. (1) The flexural strength and surface roughness of ferrite became the highest at the peripheral wheel speed of 1700m/min. (2) In the case of depth of cut larger than 0.4mm, crack layers is induced in the ground surface, the fracture type of chips exhibits slight ductile mode in the depth of cut smaller than 0.2mm. (3) When the depth of cut exceed 0.6mm, the tool life becomes extermely short due to large chipping and brackage. However, at the depth of cut .geq. 0.05mm, the diamond grain shows abrasive wear. (4) The flexural strength and surface roughness increases in proportion to the feed rate.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.12
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• pp.1322-1329
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• 2004

End-milling has been used widely in industrial system because it is effective to a material manufacturing with various shapes. Recently the end-milling processing is needed the high-precise technique with good surface roughness and rapid time in precision machine part and electronic part. The optimum mechanical vibration of main spindle, surface roughness and cutting temperature have an effect on end-milling condition such as, cutting direction, revolution of spindle, feed rate and depth of cut, etc. Therefore, this study carried to decide the working condition for optimum mechanical vibration of main spindle, surface roughness and cutting temperature using design of experiments, ANOVA and characteristic function. From the results of experimentation, mechanical vibration has an effect on revolution of spindle, radial depth of cut, and axial depth of cut. The surface roughness has an effect on cutting direction, revolution of spindle and depth of cut. And then the optimum condition used design of experiments is upward cutting In cutting direction, 600 rpm in revolution of spindle, 240 mm/min in feed rate, 2 mm in axial depth of cut and 0.25 mm in radial depth of cut. By design of experiments and characteristic function, it is effectively represented shape characteristics of mechanical vibration, surface roughness and cutting temperature in end-milling.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.3-7
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• 1995

Force generated during grinding process causes elastic defomation. The effect of this deforms a workpiecs. So grinding system is explainable using the concept of macining elasticity phenomenon. Machining elasticity is defined as ratio between the true depth of c ut, and an importnat factor to affect material removal mchanism and productivity. Generally, to produce accurate surface and dimensionally precise components operators depend on their experiences. Because of these, productivity is reduced and time is wasted. The objective of this reserch is to study the effect of grinding conditions, such as table speed, depth of cut on the machining elasticity parameter.