• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2007년도 추계 학술대회논문집
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• pp.232-235
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• 2007

A comprehensive numerical study was carried out to identify the on-set condition of the cell structures of oblique detonation waves (ODWs). Mach 7 incoming flow was considered with all other flow variables were fixed except the flow turning angles varying from 35 to 38. For a given flow conditions theoretical maximum turning angle is $38.2^{\circ}$ where the oblique detonation wave may be stabilized. The effects of grid resolution were tested using grids from $255{\times}100$ to $4,005{\times}1,600$. The numerical smoked foil records exhibits the detonation cell structures with dual triple points running opposite directions for the 36 to 38 turning angles. As the turning angle get closer to the maximum angle the cell structures gets finer and the oscillatory behavior of the primary triple point was observed. The thermal occlusion behind the oblique detonation wave was observed for the $38^{\circ}$ turning angle.

• 대한기계학회논문집
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• 제14권6호
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• pp.1542-1551
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• 1990

본 연구에서는 직경오차를 최종 다듬질 가공 직전에 선반의 주축 정지 상태에 서 공구대에 부착시킨 전기마이크로미터로 측정하는 방법을 이용하여, 어떠한 공작물 형상에 대해서도 오차 측정경로를 NC 프로그램으로 자동 생성하고 이를 이용하여 직경 오차를 측정, 보정하는 알고리즘을 제안함과 동시에 수정된 최종 다듬질 가공용 NC프 로그램을 자동적으로 생성하는 시스템을 개발하고자 한다.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.111-116
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• 2003

In this paper, object of experiment is to study on the effect of cutting parameters to obtain optimal surface toughness in face turning. Surface roughness is significantly important to be high quality of parts produced by turning process. For this purpose, the optimization of cutting parameters for fan Owning operation is investigated applying the Taguchi method. An orthogonal array, signal-to-noise ratio, and the analysis of variance are employed to evaluate effect of cutting parameters fir face turning. Also confirmation tests were performed to make a comparison between the results predicted from the mentioned correlations and the theoretical results. Cutting experiment is performed without cutting fluid using coated tungsten carbide inserts about workpieces of SM45C.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.270-276
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• 2000

Hard turning has the potential to replace grinding process and to achieve significant reduction in production time and cost. The main applications for hard turning is finishing process, namely grinding process. Therefore, it must be able to satisfy high surface integrity of the workpiece. This paper discusses surface quality in terms of residual stress and damaged layer with respect to cutting parameters in an intermittent hard turning. Damaged layer experiment is carried out orthogonal array. From that is based on the orthogonal array. From the response table, cutting parameters are analyzed from the view point of the damaged layer and residual stress. From this experimental results, even though in the intermittent hard turning, surface integrity turns out be good enough for replacing grinding process.

• 한국기계가공학회지
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• 제10권6호
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• pp.27-32
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• 2011

In recently, it is demanded development of manufacturing techniques for machining of various mechanical parts. Therefore the development of turning is one of the important manufacturing techniques. In this study, an experimental shape in tapered groove turning was suggested, and the turning process was investigated by analyzing cutting speed, feed rate, tapered angle, depth of cut. The surface roughness and cutting force change in the workpiece was measured. From the results, the optimum machining conditions are obtained by design of experiments.

• 한국기계가공학회지
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• 제11권6호
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• pp.88-93
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• 2012

In this study, Machining fine shaft was examined by Lathe. method is proposed to control the thrust force to 0. through relationship between the cutting depth and the thrust force in turning, fine-shaft of less than 0.1mm diameter in turning is confirmed experimentally. also we propose practical expression to control thrust force in turning Through to change the approach angle, optimal tool design would be possible in turning.

• Journal of Biosystems Engineering
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• 제25권5호
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• pp.399-408
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• 2000

This study is final focused on developing fruit harvesting robot can distinguish fruit type and status accurately. Multi-joint robot is able to discriminate tree shape and select mature fruit by image processing. The multi-joint robot consists of (a) rotating base, (b)turning first joint-arm, (c)rotating and turning second joint-arm, (d)rotating and turning third joint-arm, (e)rotating and turning last joint and (f)picker hand. The operational ranges of the robot are: horizontal 860~2,220mm, vertical 1,440~2,260mm, 270 degrees’rotation angle, 90 or 270 degrees’turning angle. The robot weighs 330kg. The multi-joint robot was designed in high accuracy and efficiency by getting as close as the movements of human arms and waist.

• 한국정밀공학회지
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• 제15권11호
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• pp.67-75
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• 1998

Geometric and thermal errors are key contributors to the errors of a computer numerically controlled turning center. A planar error synthesis model is obtained by synthesizing 11 geometric and thermal error components of a turning center with homogeneous coordinate transformation method. This paper shows the sensitivity analysis on the temperature change, the confidence evaluation on the uncertainty Of measurement systems, and the error contribution analysis from the planar error synthesis model. Planar error in the z direction was very sensitive to the temperature change. and planar errors in the x and z directions were not affected by the uncertainty of measurement systems. The error contribution analysis ,which is applicable to designing a new turning center, was helpful to find the large error components which affect planar errors of the turning center.

• 중국학논총
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• 제66호
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• pp.161-188
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• 2020

The purpose of this paper is to analyze the debate on the Lewisian turning point in China. Despite the heated debate and accumulating research results both inside and outside China, the results showed a very complex spectrum. Different results were presented depending on which criteria the researcher selected, which analytical tools were used, and which data were utilized. Territory of China is vast, and the differences in economic basement and development stages between regions are not only severe, but also the economic gap among areas in a region is big. Therefore, it is difficult to have a significant meaning in analyzing the Lewisian Turning Point China as a whole. In addition, China's industrial production and labor force structure remain very unbalanced. This can be said to be due to the fact that the allocation and relocation of labor force according to the stage of economic development has not been achieved reasonably, and so it confuses the task of determining whether the Lewis Turning Point has arrived of not.

• 한국정밀공학회지
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• 제12권1호
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• pp.132-141
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• 1995

This paper presents a choosing method of turning devices for stable robotic assembly based on verification of a base assembly motion instability. In flexible assembly application, the base assembly needs to be maintained in its assembled state without being taken apart. Therefore, the instability of the base assembly motion should be considered when determining the guide line of choosing turning devices by evaluating a degree of the motion instability of the base assembly. To derive the instability, first we inference collision free assembly directions by extracting separable directions for the mating parts and calculate the separability which gives informations as to how the parts can be essily separated. Using these results, we determine the instability evaluated by summing all the modified separabilites of each component part within base assembly.