• Journal of Biosystems Engineering
• /
• v.2 no.1
• /
• pp.25-32
• /
• 1977

This experiment was conducted in order to find out the drawing performance of a two-wheel tractor under different levels of the soil moisture and hardness, so as to obtain some basic data for improving their drawing performance. With fairly homogeneous soil, 5 levels of soil moisture contents (8, 13, 17, 20 and 23%) and 3 levels of soil hardness (0 , 2 and 4kg/$cm^2$) were selected for this experiment.The summerized results are as follows ;1. The draft force, on the hard soil (hardness ; 4kg/$cm^2$), had a distinct tendency to decrease with the increasing soil moisture. On the medium soil (hardness ; 2 kg/$cm^2$), and the soft soil (hardness ; 0kg$cm^2$), the draft force showed the highest when the moisture contents were within the range of 16-19%.But the maximum draft force, on the soft soil, was higher than that on the medium soil by 10 %. 2. The driving axle torque increased with increasing soil by 10 %. 3.The values of horizontal distance between the soil reaction point and axle shaft were within the range of 0~10cm , and it had the tendency to increase with the increasing soil moisture. Also, it s value was the largest on the hard soil and the smallest on the soft soil. 4.The tractive efficiency decreased with the increasing soil moisture. On the hard soil, the average value of tractive efficiency was higher than that on the medium soil by 19.0% and that on the soft soil was lower than that on the medium soil. 5.The traction ratio were within the range of 30 ~45%, and their changing tendency with respect to the soil moisture was similar to that in the case of the draft force. 6. The travel resistance ratio tended to increased with increasing soil moisture, and the highest value was found on the soft soil, and the lowest on the hard soil.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.11
• /
• pp.8030-8036
• /
• 2015

This study is to explore the effect of figure and color informations on assessing expressed emotions in drawings. A pilot study was conducted to explore emotional responses to achromatic drawing stimuli. The main experiment explored emotional responses to chromatic drawing stimuli. Each experiment has a number of 50, 56 participants separately, and responses included joy, depression, and anger according to appraisal-potency-activity dimensions. As results, achromatic drawing stimuli with their texture and rhythm produced specific emotions in high rates. Moreover, response rates of specific emotions were lower when colors added, or emotional responses were changed with colors. The significance of this study can be found in the fact that it dealt with colors combined with shape, unlike the previous studies, and that the experiments were conducted under more controlled conditions in terms of stimulus presentation and response management.

• Journal of the Korean Society for Precision Engineering
• /
• v.18 no.9
• /
• pp.186-191
• /
• 2001

Spinning process is a chipless metal forming method for axi-symmetric parts, which is more economical, efficient and versatile method for producing parts than the other sheet metal forming process such as stamping or deep drawing. In this study, a fundamental experiment was conducted to improve productivity with process parameters such as tool path, angle of roller holder($\alpha$), feed rate($\gamma$) and corner radius of forming roller(Rr). These factors were selected as variables in the experiment because they were most likely expected to hale an effect on spring back. The empirical results were analyzed to know how much spring back was affected by these factors. And also thickness and diameter distribution of a multistage cup obtained by spinning process were observed and compared with those of a commercial product produced by conventional deep drawing.

• Dementia and Neurocognitive Disorders
• /
• v.16 no.2
• /
• pp.48-53
• /
• 2017

Background and Purpose Torrance Tests of Creative Thinking (TTCT) is a well-known and commonly used measure of creativity. However, the TTCT-induced creative hemodynamic brain activity is rarely revealed. The purpose of this study is to elucidate the neural correlates of creative thinking in the setting of a modified version of the figural TTCT adapted for an functional magnetic resonance imaging (fMRI) experiment. Methods We designed a blocked fMRI experiment. Twenty-five participants (11 males, 14 females, mean age $19.9{\pm}1.8$) were asked to complete the partially presented line drawing of the figural TTCT (creative drawing imagery; creative). As a control condition, subjects were asked to keep tracking the line on the screen (line tracking; control). Results Compared to the control condition, creative condition revealed greater activation in the distributed and bilateral brain regions including the left anterior cingulate, bilateral frontal, parietal, temporal and occipital regions as shown in the previous creativity studies. Conclusions The present revealed the neural basis underlying the figural TTCT using fMRI, providing an evidence of brain areas encompassing the figural TTCT. Considering the significance of a creativity test for dementia patients, the neural correlates of TTCT elucidated by this study may be valuable to evaluate the brain function of patients in the clinical field.

• Transactions of Materials Processing
• /
• v.8 no.1
• /
• pp.14-21
• /
• 1999

Trapezoid cups and square ones have been deep-drawn to 45mm in depth. Displacements and strains have been analysed by FEM and experiment. Strains and effective strains in the corner flanges of trapezoid cups have been compared with those in square cups. The results have shown that because of shear strains on the corner flange, it is necessary to adopt effective strain for comparing strains, mean vale of effective strains in the corner flange with a corner angle of 72 degrees is narly equal to those with a corner angle of a right angle and mean value of effective strains with a corner angle of 102 degrees is smaller than those with a corner angle of a right angle.

• Transactions of Materials Processing
• /
• v.7 no.1
• /
• pp.3-11
• /
• 1998

During the forming process of sheet metals, the drawbead in the die face controls a restraining force so that the sheet flows into the die cavity with tension. In order to investigate a drawgbead restraining force and a pre-strain just after drawbeads which are essential in the finite element analysis of form-ing processes, the friction test and drawing test are employed. The experiments performed with a cir-cular bead stepped bead double circular bead and circular-and-stepped bead in the various forming conditions and bead sizes show that the restraining force varies linearly with the blank holding force. bead radius blank thickness and friction but the pre-strain nonlinearly does with them.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.2 s.95
• /
• pp.31-38
• /
• 1999

Square cups have been drawn to 20mm~60mm in depth and displacements and strains have been analysed by FEM and experiment. Displacements and strains on the corner flange of square cups have been compared with those of cylindrical cups. The results have shown that shear strains take place on corner flanges of square cups, it is necessary to adopt effective strain for comparing of stains and the effective strains on the corner flange in square cups are smaller than those in cylindrical ones.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1999.03b
• /
• pp.159-162
• /
• 1999

This study has been performed to investigate forming limit of PCM(Pre-Coated Metal) widely using appliances. Die set was made for deep drawing test and some PCMs were inrectangular deep drawing test in no-lubricant 20% clearance some die materials(STD11(TiCN) STD11(HrC60) STD11(TD) AMOCO and 6mm/sec punch speed. and Ericshen test was performed in regular conditions In this experiment forming limit forming characteistics superior die materials and fracture of PCMs been investigated. In results tested PCMs have lower forming limit than base material because lower elongation ultimate strength than base material And two-fracture types - occurring band and flaking - of PCMs have been investiqated.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 1997.03a
• /
• pp.55-58
• /
• 1997

In automotive industries, stamping of laser-welded blank gives many merits which brings about dimensional accuracy, strong body assembly and high productivity. However the welding of blanks with different thickness or/and different strength materials introduces many challenging formability problems for process development and tool design. In this paper, the deformation characteristics for deep drawing process of laser-welded blank with different thickness sheets are investigated by experiment and FEM simulation. And also the optimal location of weld line in laser-welded blank with different thickness sheets is calculated to compensate for the movement of weld line on deep drawing process. In addition, the effect of location of weld line is clarified using FEM simulation.

• Proceedings of the KSME Conference
• /
• 2000.11a
• /
• pp.754-758
• /
• 2000

Milli-structure components are classified as component group whose size is between macro and micro scale. that is, about less than 20mm and larger than 1mm. The forming of these components has a typical phenomenon of bulk deformation with thin sheets because of the forming size. In order to conventional metal forming, where numerical process simulation is already fully applied, the micro-forming process is characterized by some scale effects which have to be considered in an advanced process simulation. milli-structure rectangular cup drawing is analyzed and designed using the finite element method and experiment. The result of the finite element analysis is confirmed by a series of experiments.